RESUMEN

Introducción. En Colombia, solo un 24 % de los pacientes en lista recibieron un trasplante renal, la mayoría de donante cadavérico. Para la asignación de órganos se considera el HLA A-B-DR, pero la evidencia reciente sugiere que el HLA A-B no está asociado con los desenlaces del trasplante. El objetivo de este estudio fue evaluar la relevancia del HLA A-B-DR en la sobrevida del injerto de los receptores de trasplante renal. Métodos. Estudio de cohorte retrospectivo que incluyó pacientes trasplantados renales con donante cadavérico en Colombiana de Trasplantes, desde 2008 a 2023. Se aplicó un propensity score matching (PSM) para ajustar las covariables en grupos de comparación por compatibilidad y se evaluó la relación del HLA A-B-DR con la sobrevida del injerto renal por medio de la prueba de log rank y la regresión de Cox. Resultados. Se identificaron 1337 pacientes transplantados renales, de los cuales fueron mujeres un 38,7 %, con mediana de edad de 47 años y de índice de masa corporal de 23,8 kg/m2. Tras ajustar por PSM las covariables para los grupos de comparación, la compatibilidad del HLA A-B no se relacionó significativamente con la pérdida del injerto, con HR de 0,99 (IC95% 0,71-1,37) para HLA A y 0,75 (IC95% 0,55-1,02) para HLA B. Solo la compatibilidad por HLA DR fue significativa para pérdida del injerto con un HR de 0,67 (IC95% 0,46-0,98). Conclusión. Este estudio sugiere que la compatibilidad del HLA A-B no influye significativamente en la pérdida del injerto, mientras que la compatibilidad del HLA DR sí mejora la sobrevida del injerto en trasplante renal con donante cadavérico

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Introduction. In Colombia, only 24% of patients on the waiting list received a renal transplant, most of them from cadaveric donors. HLA A-B-DR is considered for organ allocation, but recent evidence suggests that HLA A-B is not associated with transplant outcomes. The objective of this study was to evaluate the relevance of HLA A-B-DR on graft survival in kidney transplant recipients. Methods. Retrospective cohort study that included kidney transplant recipients with a cadaveric donor in Colombiana de Trasplantes from 2008 to 2023. A propensity score matching (PSM) was applied to adjust the covariates in comparison groups for compatibility, and the relationship of HLA A-B-DR with kidney graft survival was evaluated using the log rank test and Cox regression. Results. A total of 1337 kidney transplant patients were identified; of those, 38.7% were female, with median age of 47 years, and BMI 23.8 kg/m2. After adjusting the covariates with PSM for the comparison groups, HLA A-B matching was not significantly related to graft loss, with HR of 0.99 (95% CI 0.71-1.37) and 0.75 (95% CI 0.55-1.02), respectively. Only HLA DR matching was significant for graft loss with an HR of 0.67 (95% CI 0.46-0.98). Conclusions. This study suggests that HLA A-B matching does not significantly influence graft loss, whereas HLA DR matching does improve graft survival in renal transplantation with a cadaveric donor.

Asunto(s)

Humanos , Trasplante de Riñón , Rechazo de Injerto , Antígenos HLA , Análisis de Supervivencia , Trasplante de Órganos , Puntaje de Propensión

RESUMEN

INTRODUCTION: Hematopoietic stem cell transplantation (HSCT) remains a critical treatment for advanced or high-risk hematological malignancies, posing challenges such as finding suitable donors and managing of graft-versus-host disease (GvHD). This study estimates 3-year overall survival in patients who underwent HSCT at our referral service in the state of Minas Gerais, Brazil. MATERIAL AND METHODS: This retrospective observational cohort study involved 41 patients who received HSCT between 2017 and 2021 at the Felício Rocho Hospital. Recipients received HSCT from either haploidentical donor (Haplo), matched unrelated donor (MUD), or HLA-matched sibling donor (MSD). The study evaluated parameters that included 3-year overall survival (OS), treatment-related mortality (TRM), GvHD incidence, post-transplant relapse rate, and engraftment. ANOVA, Kruskal-Wallis, and chi-square tests were used for statistical analysis. Survival curves were calculated using the Kaplan-Meier method and the Log-rank test compared the curves. RESULTS: Our study found that the engraftment time differed among groups: Haplo recipients engrafted earlier within a median of 16 days (ranging between 10 and 20 days) than MSD recipients with 18 days (ranging between 11 and 28 days), and MUD recipients with 19 days (ranging between 11 and 24 days; p = 0.019). Mild acute GvHD (grade I-II) was observed in 13 patients, progressing to chronic GvHD in 5 patients. Three-year OS rates were as follows: MSD group - 67.7%, Haplo group - 42.2%, and MUD group - 44.4% (MSD vs Haplo, p = 0.039). Three-year cumulative treatment-related mortality (TRM) rates were 17.8% for MSD group, 22.9% for Haplo group, and 22.1% for MUD group (pairwise comparisons p > 0.05). Infection-related mortality was reported in eight patients, while relapse rates at 3 years were similar across MSD, Haplo, and MUD groups (p = 0.891). Donor age influenced OS rates, showing better outcomes with donors under 45 years old, and significant differences were found in pairwise comparisons (p = 0.015). CONCLUSION: Donor type and donor age significantly impacted HSCT outcomes in our analysis, thus emphasizing the importance of rigorous donor selection in risk stratification and suggesting potential benefits for younger donors.

Asunto(s)

Enfermedad Injerto contra Huésped , Trasplante de Células Madre Hematopoyéticas , Humanos , Persona de Mediana Edad , Trasplante de Células Madre Hematopoyéticas/efectos adversos , Trasplante de Células Madre Hematopoyéticas/métodos , Recurrencia Local de Neoplasia/complicaciones , Recurrencia , Estudios Retrospectivos , Hermanos , Donante no Emparentado , Adulto

RESUMEN

Immunotherapy aims to stimulate the immune system to inhibit tumor growth or prevent metastases. Tumor cells primarily employ altered expression of human leukocyte antigen (HLA) as a mechanism to avoid immune recognition and antitumor immune response. The antitumor immune response is primarily mediated by CD8+ cytotoxic T cells (CTLs) and natural killer (NK) cells, which plays a key role in the overall anti-tumor immune response. It is crucial to comprehend the molecular events occurring during the activation and subsequent regulation of these cell populations. The interaction between antigenic peptides presented on HLA-I molecules and the T-cell receptor (TCR) constitutes the initial signal required for T cell activation. Once activated, in physiologic circumstances, immune checkpoint expression by T cells suppress T cell effector functions when the antigen is removed, to ensures the maintenance of self-tolerance, immune homeostasis, and prevention of autoimmunity. However, in cancer, the overexpression of these molecules represents a common method through which tumor cells evade immune surveillance. Numerous therapeutic antibodies have been developed to inhibit immune checkpoints, demonstrating antitumor activity with fewer side effects compared to traditional chemotherapy. Nevertheless, it's worth noting that many immune checkpoint expressions occur after T cell activation and consequently, altered HLA expression on tumor cells could diminish the clinical efficacy of these antibodies. This review provides an in-depth exploration of immune checkpoint molecules, their corresponding blocking antibodies, and their clinical applications.

Asunto(s)

Neoplasias , Humanos , Linfocitos T Citotóxicos , Inmunoterapia/métodos , Células Asesinas Naturales , Anticuerpos , Antígenos de Histocompatibilidad Clase I , Antígenos HLA

RESUMEN

Abstract Introduction: Sensitization to human leukocyte antigen is a barrier to. Few data have been published on desensitization using polyvalent human intravenous immunoglobulin (IVIG) alone. Methods: We retrospectively reviewed the of 45 patients with a positive complement-dependent cytotoxicity crossmatch (CDCXM) or flow cytometry crossmatch (FCXM) against living donors from January 2003 to December 2014. Of these, 12 were excluded. Patients received monthly IVIG infusions (2 g/kg) only until they had a negative T-cell and B-cell FCXM. Results: During the 33 patients, 22 (66.7%) underwent living donor kidney transplantation, 7 (21.2%) received a deceased donor graft, and 4 (12.1%) did not undergo transplantation. The median class I and II panel reactive antibodies for these patients were 80.5% (range 61%-95%) and 83.0% (range 42%-94%), respectively. Patients (81.8%) had a positive T-cell and/or B-cell CDCXM and 4 (18.2%) had a positive T-cell and/or B-cell FCXM. Patients underwent transplantation after a median of 6 (range 3-16). The median donor-specific antibody mean fluorescence intensity sum was 5057 (range 2246-11,691) before and 1389 (range 934-2492) after desensitization (p = 0.0001). Mean patient follow-up time after transplantation was 60.5 (SD, 36.8) months. Nine patients (45.0%). Death-censored graft survival at 1, 3, and 5 years after transplant was 86.4, 86.4, and 79.2%, respectively and patient survival was 95.5, 95.5, and 83.7%, respectively. Conclusions: Desensitization using IVIG alone is an effective strategy, allowing successful transplantation in 87.9% of these highly sensitized patients.

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Resumo Introdução: Sensibilização HLA é uma barreira ao transplante em pacientes sensibilizados. Há poucos dados publicados sobre dessensibilização utilizando somente imunoglobulina intravenosa humana polivalente (IgIV). Métodos: Revisamos retrospectivamente prontuários de 45 pacientes com prova cruzada positiva por citotoxicidade dependente do complemento (CDCXM) ou citometria de fluxo (FCXM) contra doadores vivos, de Janeiro/2003-Dezembro/2014. Destes, excluímos 12. 33 pacientes receberam infusões mensais de IgIV (2 g/kg) apenas até apresentarem FCXM células T e B negativa. Resultados: Durante dessensibilização, 22 pacientes (66,7%) realizaram transplante renal com doador vivo, 7 (21,2%) receberam enxerto de doador falecido, 4 (12,1%) não realizaram transplante. A mediana do painel de reatividade de anticorpos classes I e II para estes pacientes foi 80,5% (intervalo 61%-95%) e 83,0% (intervalo 42%-94%), respectivamente. 18 pacientes (81,8%) apresentaram CDCXM célula T e/ou B positiva; 4 (18,2%) apresentaram FCXM célula T e/ou B positiva. Pacientes realizaram transplante após mediana de 6 (intervalo 3-16) infusões. A mediana da somatória da intensidade média de fluorescência do anticorpo específico contra o doador foi 5057 (intervalo 2246-11.691) antes e 1389 (intervalo 934-2492) após dessensibilização (p = 0,0001). O tempo médio de acompanhamento do paciente pós transplante foi 60,5 (DP, 36,8) meses. Nove pacientes (45,0%) não apresentaram rejeição e 6 (27,3%) apresentaram rejeição mediada por anticorpos. Sobrevida do enxerto censurada para óbito em 1, 3, 5 anos após transplante foi 86,4; 86,4; 79,2%, respectivamente, e sobrevida do paciente foi 95,5; 95,5; 83,7%, respectivamente. Conclusões: Dessensibilização utilizando apenas IgIV é uma estratégia eficaz, permitindo transplante bem-sucedido em 87,9% destes pacientes altamente sensibilizados.

RESUMEN

ABSTRACT Objective: Describe the clinical and laboratory characteristics and the transfusion strategy of patients at Hospital Israelita Albert Einstein with platelet refractoriness and identify their etiological characteristics. Standardize the platelet immunofluorescence technique by flow cytometry as a test for platelet compatibility in immune platelet refractoriness in transfusion support. Methods: Review of medical records of refractory platelet patients followed at HIAE from January 2011 to May 2017. Clinical-demographic data, laboratory data and identification of the use of compatible genotyped platelets for patients in need of transfusion therapy were collected. The analyzed patients were classified according to the etiology of their platelet refractoriness. To standardize the FC-PIFT technique, blood group O platelets were incubated with serum from blood group AB donors and anti-IgG monoclonal antibody to determine the negative control. In order to verify the influence of the ABO system, monoclonal anti-IgG antibodies were incubated with blood group A or B platelets and with blood group O donor serum with isohemagglutinins below and above 1/64. Results: A total of 47 patients were evaluated, a 51% (24/47) preponderance of associated immune and non-immune factors (NIPR + IPR). The most common causes of NIPR + IPR were splenomegaly (54%) and the development of HLA antibodies (88%), consistent with the literature. For patients who required therapeutic transfusion, only a small portion received compatible genotyped platelets. Conclusion: Although 60% of patients could benefit from the therapeutic transfusion of genotyped platelets, only 10% were actually transfused with this type of blood component. This reaffirms the need for investments in a bank of genotyped platelet donors.

Asunto(s)

Antígenos de Plaqueta Humana , Técnica del Anticuerpo Fluorescente Indirecta , Citometría de Flujo , Antígenos HLA , Anticuerpos

RESUMEN

Abstract Background: Bullous pemphigoid (BP) associated with milia lesions has been increasingly reported, but its prevalence has not been reported in a Brazilian BP population yet. Objectives: To describe the occurrence and clinical-laboratorial findings of BP-milia association in a southeastern Brazilian sample. Methods: A descriptive study based on the medical charts of 102 BP patients was accomplished. Clinical and laboratory data of BP-milia patients were compiled. Total serum IgE measurements, immunoblot assays based on basement membrane zone antigens, and HLA-DQ alleles typing were performed. Results: Milia was evident in 8 (7.8%) BP patients, five males, aged between 46 and 88 years. Increased total IgE levels were determined in 7 (87.5%) of the eight patients. In five of eight patients, immunoblotting showed IgG reactivity against the BP180-NC16a domain but not against collagen VII or laminin-332; it also revealed reactivity against the BP180 C-terminal domain or LAD-1, or both in four of them. The HLA-DQB1*03:01 and HLA-DQA1*05:05 alleles were identified in three of five BP-milia patients. Moreover, three of five cases presented the HLA-DQB1*06 allelic group. Study limitations: HLA determination was performed in five patients. Conclusions: Milia formation in BP patients seems to be less uncommon than previously admitted. Laboratory data revealed increased IgE; autoantibodies against the BP180 C-terminal domain or LAD-1, or both; and the HLA-DQB1*06 allelic group, described for the BP-milia association. Careful determination of antibodies against basement membrane zone molecules and HLA characterization in different populations may provide further insights into this association. © 2022 Sociedade Brasileira de Dermatologia. Published by Elsevier España, S.L.U. This is an open access article under the CC BY license (https://creativecommons.org/licenses/by/4.0/).

RESUMEN

The presence of antibodies directed against human leukocyte antigens (HLA) expressed on donor cells is a significant risk factor for serious clinical complications after transplantation. The crossmatch assay is one of the most important tests available for the detection of donor-specific antibodies in potential allograft recipients. Early crossmatch methods utilized complement-dependent cytotoxicity, which is useful for detecting the donor-specific anti-HLA antibodies responsible for hyperacute allograft rejection but lacks adequate sensitivity. Consequently, more sensitive crossmatch methods have been developed, ultimately leading to the flow cytometry crossmatch as the currently preferred methodology. Herein, we review the evolution of the crossmatch assay and the most important factors to consider when performing and interpreting the results of this fundamental assay for ensuring the long-term survival of the transplanted organ.

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La presencia de anticuerpos dirigidos contra los antígenos leucocitarios humanos (Human Leukocyte Antigens, HLA) que se expresan en las células del donante, es uno de los factores de riesgo más importantes asociados con las complicaciones clínicas después del trasplante. La prueba cruzada es una de las pruebas de histocompatibilidad más eficaces para la detección de anticuerpos específicos contra el donante en los receptores de injertos. En los primeros métodos de la prueba cruzada, se utilizaba la citotoxicidad dependiente del complemento, que es útil para detectar dichos anticuerpos responsables del rechazo hiperagudo del injerto, pero carece de la sensibilidad adecuada. Por ello, se desarrollaron métodos de pruebas cruzadas más sensibles, entre ellas, la prueba cruzada por citometría de flujo que hoy se considera el método preferido. En este artículo se revisa la evolución de la prueba cruzada y los factores más importantes que deben tenerse en cuenta al realizarla y al interpretar los resultados de esta prueba fundamental para la supervivencia a largo plazo del injerto.

RESUMEN

Multiple sclerosis is a neurodegenerative and autoimmune disease of the central nervous system that mainly affects young people, especially women; its origin has been associated with infection caused by the Epstein-Barr virus. However, not all people who have suffered infection by this virus develop multiple sclerosis, so it would be important to know the role of genetic variability, especially the individual allelic variability of the human leukocyte antigen; as well as to determine the molecular mechanisms and the immunological links of the virus when it remains latent inside the B lymphocytes. Based on the above, it could be defined if the virus is a necessary condition to develop the disease or if there are other factors that need to be present, and thus be able to establish specific prevention and treatment strategies. But the most relevant thing is that the virus is a present condition to develop multiple sclerosis and is potentially preventable through the design of the respective vaccine.

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La esclerosis múltiple es una enfermedad neurodegenerativa y autoinmune del sistema nervioso central que afecta, principalmente, a personas jóvenes, sobre todo a mujeres; su origen se ha asociado con la infección provocada por el virus Epstein-Barr. Sin embargo, no todas las personas que han padecido la infección por este virus desarrollan esclerosis múltiple, por lo que sería importante conocer el rol de la variabilidad genética, en especial la variabilidad alélica individual del antígeno leucocitario humano; así como determinar los mecanismos moleculares y los vínculos inmunológicos del virus cuando permanece latente al interior de los linfocitos B. Por lo antes expuesto, se podría definir si el virus es una condición necesaria para desarrollar la enfermedad o si existen otros factores que necesitan estar presentes, y de esta manera poder establecer las estrategias específicas de prevención y tratamiento. Pero lo más relevante es que el virus es una condición presente para desarrollar la esclerosis múltiple y es potencialmente prevenible mediante el diseño de la vacuna respectiva.

Asunto(s)

Infecciones por Virus de Epstein-Barr , Esclerosis Múltiple , Adolescente , Sistema Nervioso Central , Infecciones por Virus de Epstein-Barr/complicaciones , Femenino , Herpesvirus Humano 4/genética , Humanos , Esclerosis Múltiple/genética

RESUMEN

OBJECTIVE(S): This study aimed investigate association of HLA-DRB1 and cytokine polymorphisms with red blood cell(RBC) alloimmunization in Brazilian Myelodysplastic syndrome(MDS) patients with prior exposure to RBC transfusion. BACKGROUND: MDS patients are at risk RBC alloimmunization due to chronic RBC transfusion. However, differences in immune response of MDS transfused patients are not completely known. METHODS/MATERIALS: A retrospective cohort of 87 polytransfused patients with MDS including 28 alloimmunized (PA) and 59 non-alloimmunized (PNA) was evaluated in three Brazilian reference hospitals. HLA-DRB1genotype was performed by polymerase chain reaction (PCR)-SSOP (Luminex platform) and cytokine polymorphisms analysed by PCR and TaqMan assays. RESULTS: While HLA-DRB1 allele frequencies did not differ between groups, IL17A 197G > A SNP and IL4 polymorphisms showed significant correlation with RBC alloimmunization. IL17A 197A allele A and AA genotype were significantly more frequent in PA than PNA(A, 46.4% versus 27.1%, p = 0.012; OR = 2.3; 95%CI = 1.1-4.9; AA, 25% versus 6.8%, p = 0.041; OR = 6.2; 95%CI 1.3-30.8). Moreover, significant association of alloimmunization to Rh antigens with IL17A 197A allele and AA genotype was also identified in PA group(A, 45% versus 27.1%, p = 0.036; OR = 2.5; 95% CI 1.1-5.7; AA, 30% versus 6.8%, p = 0.042; OR = 7.9; 95%CI 1.5-42.3). Genotype A1A2 of IL4 intron 3 was overrepresented in PA(50% versus 16.9%, p = 0.009; OR = 4.97; 95%CI 1.6-15.5). Similarly, IL4-590 CT genotype was overrepresented in PA(53.6% versus 28.8%, p = 0.049; OR = 3.3; 95%CI 1.2-9.3). CONCLUSIONS: This study showed no association regarding HLA-DRB1 alleles for RBC alloimmunization risk or protection, however the IL17A 197G>A, IL4 intron 3 and IL4 590C>T SNP was significantly associated to RBC alloimmunization risk in this cohort of Brazilian MDS patients.

Asunto(s)

Anemia Hemolítica Autoinmune , Cadenas HLA-DRB1 , Interleucina-17 , Interleucina-4 , Síndromes Mielodisplásicos , Anemia Hemolítica Autoinmune/genética , Brasil , Citocinas/genética , Eritrocitos , Cadenas HLA-DRB1/genética , Humanos , Interleucina-17/genética , Interleucina-4/genética , Isoanticuerpos , Síndromes Mielodisplásicos/genética , Síndromes Mielodisplásicos/terapia , Estudios Retrospectivos

RESUMEN

La presencia de anticuerpos dirigidos contra los antígenos leucocitarios humanos (Human Leukocyte Antigens, HLA) que se expresan en las células del donante, es uno de los factores de riesgo más importantes asociados con las complicaciones clínicas después del trasplante. La prueba cruzada es una de las pruebas de histocompatibilidad más eficaces para la detección de anticuerpos específicos contra el donante en los receptores de injertos. En los primeros métodos de la prueba cruzada, se utilizaba la citotoxicidad dependiente del complemento, que es útil para detectar dichos anticuerpos responsables del rechazo hiperagudo del injerto, pero carece de la sensibilidad adecuada. Por ello, se desarrollaron métodos de pruebas cruzadas más sensibles, entre ellas, la prueba cruzada por citometría de flujo que hoy se considera el método preferido. En este artículo se revisa la evolución de la prueba cruzada y los factores más importantes que deben tenerse en cuenta al realizarla y al interpretar los resultados de esta prueba fundamental para la supervivencia a largo plazo del injerto.

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The presence of antibodies directed against human leukocyte antigens (HLA) expressed on donor cells is a significant risk factor for serious clinical complications after transplantation. The crossmatch assay is one of the most important tests available for the detection of donor-specific antibodies in potential allograft recipients. Early crossmatch methods utilized complement-dependent cytotoxicity, which is useful for detecting the donor-specific anti- HLA antibodies responsible for hyperacute allograft rejection but lacks adequate sensitivity. Consequently, more sensitive crossmatch methods have been developed, ultimately leading to the flow cytometry crossmatch as the currently preferred methodology. Herein, we review the evolution of the crossmatch assay and the most important factors to consider when performing and interpreting the results of this fundamental assay for ensuring the long-term survival of the transplanted organ.

Asunto(s)

Trasplante de Órganos , Histocompatibilidad , Pruebas Inmunológicas de Citotoxicidad , Citometría de Flujo , Antígenos HLA

RESUMEN

BACKGROUND: Bullous pemphigoid (BP) associated with milia lesions has been increasingly reported, but its prevalence has not been reported in a Brazilian BP population yet. OBJECTIVES: To describe the occurrence and clinical-laboratorial findings of BP-milia association in a southeastern Brazilian sample. METHODS: A descriptive study based on the medical charts of 102 BP patients was accomplished. Clinical and laboratory data of BP-milia patients were compiled. Total serum IgE measurements, immunoblot assays based on basement membrane zone antigens, and HLA-DQ alleles typing were performed. RESULTS: Milia was evident in 8 (7.8%) BP patients, five males, aged between 46 and 88 years. Increased total IgE levels were determined in 7 (87.5%) of the eight patients. In five of eight patients, immunoblotting showed IgG reactivity against the BP180-NC16a domain but not against collagen VII or laminin-332; it also revealed reactivity against the BP180 C-terminal domain or LAD-1, or both in four of them. The HLA-DQB1*03:01 and HLA-DQA1*05:05 alleles were identified in three of five BP-milia patients. Moreover, three of five cases presented the HLA-DQB1*06 allelic group. STUDY LIMITATIONS: HLA determination was performed in five patients. CONCLUSIONS: Milia formation in BP patients seems to be less uncommon than previously admitted. Laboratory data revealed increased IgE; autoantibodies against the BP180 C-terminal domain or LAD-1, or both; and the HLA-DQB1*06 allelic group, described for the BP-milia association. Careful determination of antibodies against basement membrane zone molecules and HLA characterization in different populations may provide further insights into this association.

Asunto(s)

Queratosis , Penfigoide Ampolloso , Anciano , Anciano de 80 o más Años , Autoanticuerpos , Autoantígenos , Brasil , Humanos , Inmunoglobulina E , Queratosis/patología , Laboratorios Clínicos , Masculino , Persona de Mediana Edad , Colágenos no Fibrilares , Penfigoide Ampolloso/patología , Prevalencia

RESUMEN

El síndrome de erupción medicamentosa con eosinofilia y síntomas sistémicos (drug reaction with eosinophilia and systemic symptoms, DRESS), también conocido como síndrome de hipersensibilidad inducida por medicamentos, es una reacción rara potencialmente mortal que causa una erupción grave y que puede provocar insuficiencia multiorgánica. Como con otras erupciones medicamentosas graves, los linfocitos T específicos para un medicamento tienen una función crucial en el síndrome DRESS. El modelo de hapteno/pro-hapteno, el modelo de interacción farmacológica y el modelo alterado de repertorio de péptidos son tres modelos diferentes desarrollados para describir la relación/interacción entre un medicamento o sus metabolitos y el sistema inmunitario. Analizamos nuestra experiencia con el tratamiento con ciclosporina en un caso de síndrome DRESS resistente a esteroides causado por ácido valproico en una niña y sus resultados clínicos, de laboratorio y de antígeno leucocitario humano (HLA).

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Drug reaction with eosinophilia and systemic symptoms (DRESS), also known as drug-induced hypersensitivity syndrome, is a potentially life-threatening rare reaction that causes a severe rash and can lead to multiorgan failure. As in other severe drug eruptions, drug-specific T lymphocytes play a crucial role in DRESS. The hapten/pro-hapten model, pharmacological interaction model, and altered peptide repertoire model are three different models developed to describe the relationship/interaction between a medication or its metabolites and the immune system. We discuss our experience with cyclosporine treatment in a steroid-resistant DRESS syndrome caused by valproic acid in a girl, as well as her clinical, laboratory, and human leukocyte antigens (HLA) study results

Asunto(s)

Humanos , Femenino , Adolescente , Eosinofilia/complicaciones , Eosinofilia/inducido químicamente , Síndrome de Hipersensibilidad a Medicamentos/diagnóstico , Síndrome de Hipersensibilidad a Medicamentos/etiología , Ácido Valproico/efectos adversos , Ciclosporina , Haptenos/efectos adversos , Antígenos HLA/efectos adversos

RESUMEN

Drug reaction with eosinophilia and systemic symptoms (DRESS), also known as drug-induced hypersensitivity syndrome, is a potentially life-threatening rare reaction that causes a severe rash and can lead to multiorgan failure. As in other severe drug eruptions, drug-specific T lymphocytes play a crucial role in DRESS. The hapten/pro-hapten model, pharmacological interaction model, and altered peptide repertoire model are three different models developed to describe the relationship/interaction between a medication or its metabolites and the immune system. We discuss our experience with cyclosporine treatment in a steroid-resistant DRESS syndrome caused by valproic acid in a girl, as well as her clinical, laboratory, and human leukocyte antigens (HLA) study results.

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El síndrome de erupción medicamentosa con eosinofilia y síntomas sistémicos (drug reaction with eosinophilia and systemic symptoms, DRESS), también conocido como síndrome de hipersensibilidad inducida por medicamentos, es una reacción rara potencialmente mortal que causa una erupción grave y que puede provocar insuficiencia multiorgánica. Como con otras erupciones medicamentosas graves, los linfocitos T específicos para un medicamento tienen una función crucial en el síndrome DRESS. El modelo de hapteno/pro-hapteno, el modelo de interacción farmacológica y el modelo alterado de repertorio de péptidos son tres modelos diferentes desarrollados para describir la relación/interacción entre un medicamento o sus metabolitos y el sistema inmunitario. Analizamos nuestra experiencia con el tratamiento con ciclosporina en un caso de síndrome DRESS resistente a esteroides causado por ácido valproico en una niña y sus resultados clínicos, de laboratorio y de antígeno leucocitario humano (HLA).

Asunto(s)

Síndrome de Hipersensibilidad a Medicamentos , Eosinofilia , Niño , Ciclosporina/efectos adversos , Síndrome de Hipersensibilidad a Medicamentos/diagnóstico , Síndrome de Hipersensibilidad a Medicamentos/etiología , Eosinofilia/inducido químicamente , Eosinofilia/complicaciones , Femenino , Antígenos HLA/efectos adversos , Haptenos/efectos adversos , Humanos , Ácido Valproico/efectos adversos

RESUMEN

OBJECTIVE: Describe the clinical and laboratory characteristics and the transfusion strategy of patients at Hospital Israelita Albert Einstein with platelet refractoriness and identify their etiological characteristics. Standardize the platelet immunofluorescence technique by flow cytometry as a test for platelet compatibility in immune platelet refractoriness in transfusion support. METHODS: Review of medical records of refractory platelet patients followed at HIAE from January 2011 to May 2017. Clinical-demographic data, laboratory data and identification of the use of compatible genotyped platelets for patients in need of transfusion therapy were collected. The analyzed patients were classified according to the etiology of their platelet refractoriness. To standardize the FC-PIFT technique, blood group O platelets were incubated with serum from blood group AB donors and anti-IgG monoclonal antibody to determine the negative control. In order to verify the influence of the ABO system, monoclonal anti-IgG antibodies were incubated with blood group A or B platelets and with blood group O donor serum with isohemagglutinins below and above 1/64. RESULTS: A total of 47 patients were evaluated, a 51% (24/47) preponderance of associated immune and non-immune factors (NIPR + IPR). The most common causes of NIPR + IPR were splenomegaly (54%) and the development of HLA antibodies (88%), consistent with the literature. For patients who required therapeutic transfusion, only a small portion received compatible genotyped platelets. CONCLUSION: Although 60% of patients could benefit from the therapeutic transfusion of genotyped platelets, only 10% were actually transfused with this type of blood component. This reaffirms the need for investments in a bank of genotyped platelet donors.

RESUMEN

AIMS: Brazil is nowadays one of the epicentres of the severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) pandemic and new therapies are needed to face it. In the context of specific immune response against the virus, a correlation between Major Histocompatibility Complex Class I (MHC-I) and the severity of the disease in patients with COVID-19 has been suggested. Aiming at better understanding the biology of the infection and the immune response against the virus in the Brazilian population, we analysed SARS-CoV-2 protein S peptides in order to identify epitopes able to elicit an immune response mediated by the most frequent MHC-I alleles using in silico methods. METHODS: Our analyses consisted in searching for the most frequent Human Leukocyte Antigen (HLA)-A, HLA-B and HLA-C alleles in the Brazilian population, excluding the genetic isolates; then, we performed: molecular modelling for unsolved structures, MHC-I binding affinity and antigenicity prediction, peptide docking and molecular dynamics of the best fitted MHC-I/protein S complexes. RESULTS: We identified 24 immunogenic epitopes in the SARS-CoV-2 protein S that could interact with 17 different MHC-I alleles (namely, HLA-A*01:01; HLA-A*02:01; HLA-A*11:01; HLA-A*24:02; HLA-A*68:01; HLA-A*23:01; HLA-A*26:01; HLA-A*30:02; HLA-A*31:01; HLA-B*07:02; HLA-B*51:01; HLA-B*35:01; HLA-B*44:02; HLA-B*35:03; HLA-C*05:01; HLA-C*07:01 and HLA-C*15:02) in the Brazilian population. CONCLUSIONS: Being aware of the intrinsic limitations of in silico analysis (mainly the differences between the real and the Protein Data Bank (PDB) structure; and accuracy of the methods for simulate proteasome cleavage), we identified 24 epitopes able to interact with 17 MHC-I more frequent alleles in the Brazilian population that could be useful for the development of strategic methods for vaccines against SARS-CoV-2.

Asunto(s)

Mapeo Epitopo , Epítopos , Antígenos HLA/inmunología , Antígenos de Histocompatibilidad Clase I/inmunología , SARS-CoV-2/inmunología , Glicoproteína de la Espiga del Coronavirus/inmunología , Brasil , Frecuencia de los Genes , Antígenos HLA/genética , Antígenos de Histocompatibilidad Clase I/genética , Interacciones Huésped-Patógeno , Humanos , Simulación del Acoplamiento Molecular , Simulación de Dinámica Molecular , Unión Proteica , Conformación Proteica , SARS-CoV-2/patogenicidad

RESUMEN

ABSTRACT Objective To determine the frequency of Human leukocyte antigen alleles and to verify the association of the presence of these alleles with symptoms and other diseases related to celiac disease in patients with autoimmune thyroid diseases. Methods A questionnaire on the symptoms and diseases associated with celiac disease was applied. Genomic deoxyribonucleic acid was extracted by collecting cells from the oral mucosa. The alleles (DQA1*0501; DQB1*0201; DRB1*04) were identified by means of the polymerase chain reaction. Results A total of 110 patients with autoimmune thyroid diseases participated in this study. It was observed that 66.4% of the individuals carried at least one of the alleles assessed and that 58.2% of the individuals were positive for at least one of the DQ2 alleles (DQA1*0501; DQB1*0201) and out of these 18.2% were positive for both DQ2 alleles (DQA1*0501; DQB1*0201). With regard to DQ8 (DRB1*04), 21.8% of the studied population was positive for this allele and 3.6% was positive for both DQ2 (DQA1*0501; DQB1*0201) and DQ8 (DRB1*04). A significant association was found between the presence of the DRB1*04 allele and gastrointestinal symptoms (p=0.02). A significant association of the DRB1*04 allele with type 1 diabetes mellitus (p=0.02) was observed. Conclusion The genetic profiles most commonly associated with celiac disease, such as DQ2 (DQA1*0501; DQB1*0201) and DQ8 (DRB1*04) were around 20.0% prevalent in the studied population. These are risk haplotypes for celiac disease especially when symptoms and diseases related to celiac disease are present. Therefore, it is important to screen patients to investigate a potential diagnosis for celiac disease.

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RESUMO Objetivo Determinar a frequência dos alelos do Human leukocyte antigen e verificar a associação da presença desses alelos com sintomas e outras doenças relacionados à doença celíaca em portadores de doenças autoimunes da tireoide. Métodos Aplicou-se um questionário relacionado aos sintomas e doenças associados à doença celíaca. O ácido desoxirribonucleico genômico foi extraído por meio da coleta das células da mucosa bucal. Os alelos (DQA1*0501; DQB1*0201; DRB1*04) foram identificados por meio da reação em cadeia da polimerase. Resultados Participaram deste estudo 110 portadores de doenças autoimunes da tireoide. Observou-se que 66,4% dos indivíduos carregavam pelo menos um dos alelos estudados e que 58,2% dos indivíduos eram positivos para pelo menos um dos alelos DQ2 (DQA1*0501; DQB1*0201) e destes 18,2% foram positivos para ambos alelos do DQ2(DQA1*0501; DQB1*0201). Com relação ao DQ8 (DRB1*04), 21,8% da população estudada eram positivos para esse alelo e 3,6% eram positivos tanto para o DQ2 (DQA1*0501; DQB1*0201) quanto para o DQ8 (DRB1*04). Foi encontrada associação significativa da presença do alelo DRB1*04 com os sintomas gastrointestinais (p=0,02). Houve associação significativa do alelo DRB1*04 com diabetes mellitus tipo 1 (p=0,02). Conclusão O perfil genético mais fortemente associado à doença celíaca, tais como DQ2 (DQA1*0501; DQB1*0201) e DQ8 (DRB1*04) estavam presentes em torno de 20,0% da população estudada, estes são haplótipos de risco para doença celíaca e principalmente na presença de sintomas e doenças relacionadas à doença celíaca. Sendo assim, é importante realizar o rastreamento para investigar um possível diagnóstico para doença celíaca.

Asunto(s)

Humanos , Masculino , Femenino , Adulto , Persona de Mediana Edad , Anciano , Tiroiditis Autoinmune , Enfermedad Celíaca , Antígenos HLA , Alelos

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A neutropenia aloimune neonatal (NAN) é uma patologia causada pelo antagonismo imunológico, como a doença hemolítica do recém-nascido ou a trombocitopenia aloimune neonatal, mas relacionada aos neutrófilos, em vez de glóbulos vermelhos ou plaquetas. Descreveremos um caso clínico de duas gêmeas idênticas nascidas a termo, com Apgar de 8 e 9, sendo que após algumas horas do nascimento apresentaram febre. Um exame de sangue revelou neutropenia grave que resultou em sepse. O diagnóstico da NAN foi realizado clinicamente e por testes de histocompatibilidade. A prova cruzada por citometria de fluxo foi positiva, usando soro da mãe e suspensões celulares (granulócitos e linfócitos) das gêmeas e do pai. Este teste não fornece informações sobre para qual sistema genético os anticorpos foram positivos, se contra os antígenos específicos de neutrófilos humanos (HNA) ou contra os antígenos leucocitários humanos (HLA). Para o esclarecimento, realizamos o teste de aglutinação de granulócitos (GAT) com um painel de doadores fidelizados e com antígenos HNA1-5 conhecidos, utilizando o soro materno como reagente. Foi também realizada a pesquisa de anticorpos anti-HLA e anti-HNA no soro materno. Os genótipos HLA e HNA foram identificados, permitindo conhecer as especificidades dos anticorpos maternos contra os antígenos dos neutrófilos do marido e das filhas. O diagnóstico de NAN não é realizado na maioria dos hospitais de nosso país e do exterior, devido à dificuldade de execução dos testes de histocompatibilidade, no entanto a prova cruzada por citometria de fluxo pode facilmente ser implantada nos laboratórios clínicos, sendo que está descrita detalhadamente nesse caso clínico.

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Neonatal alloimmune neutropenia (NAN) is a disease caused by immunological antagonism, such as hemolytic disease of the newborn or neonatal alloimmune thrombocytopenia, but related to neutrophils rather than to red blood cells or platelets. We will describe a clinical case of two identical twins born with Apgar 8 and 9 that started with fever few hours after delivery. A blood test revealed severe neutropenia, which was followed by sepsis. The diagnosis of NAN was done clinically and by histocompatibility testing. Flow cytometry crossmatch was positive, using mother serum and cell suspensions (granulocytes and lymphocytes) from the twin girls and from the father. This test did not provide information about the genetic system for which the antibodies are positive, if against human neutrophil antigens (HNA) or human leucocyte antigens (HLA). To clear this, the granulocyte agglutination test (GAT) was performed with a panel of control donors with known HNA1-5 antigens, using the maternal serum as a reagent. We did also a Luminex screening assay for detection of anti-HLA and anti-HNA antibodies in the mother serum. The HLA and HNA genotypes were identified, which allowed to define specificities in mother's antibodies against the neutrophil surface antigens from her husband and from the twins. The diagnosis of NAN diagnose is not done in most hospitals worldwide, mainly by the difficulty in executing the histocompatibility test. However, the crossmatch by flow cytometry could be easily done in clinical laboratories following the method described in this article.

Asunto(s)

Recién Nacido , Gemelos Monocigóticos , Trombocitopenia Neonatal Aloinmune , Antígenos HLA , Padres , Pruebas de Aglutinación , Prueba de Histocompatibilidad , Linfocitos , Células , Aglutinación , Parto , Diagnóstico , Citometría de Flujo , Pruebas Hematológicas , Histocompatibilidad , Neutropenia

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Abstract Introduction: Renal fibrosis is the end point of a process that begins at transplant, with ischemia reperfusion and early inflammation, and progresses over time with immunological and non-immunological phenomena. Early identification of morphological markers and intervention could improve graft function and survival. Objective: to evaluate the correlation between intensity and specificity of pre-transplant anti-HLA antibodies and kidney allograft pathology in order to identify early risk factors or markers of allograft dysfunction. Methods: A retrospective cohort of kidney transplant recipients with pre-transplant anti-HLA antibodies who underwent graft biopsy within the first two years post-transplant was divided into two groups according to the specificity of anti-HLA antibodies: nonspecific (non-DSA, n = 29) and specific (DSA+, n = 16). Kidney graft pathology, renal function, and proteinuria were analyzed. Results: general characteristics were similar in both groups, except for the higher dose of thymoglobulin in DSA+ group (p < 0.05). The non-DSA group had higher scores for glomerulosclerosis, interstitial inflammation (i) and interstitial fibrosis (ci) (p < 0.05) and higher incidence of cell-mediated acute rejection. No statistical difference in incidence of antibody-mediated rejection, renal function, and proteinuria was observed during follow up. Discussion and conclusions: the difference in inflammation scores and interstitial fibrosis may be associated to the higher incidence of acute cell-mediated rejection and polyomavirus nephropathy in the Non-DSA group. We also should take into account the protective effect of higher doses of thymoglobulin, reducing ischemia reperfusion injury in the DSA+ group. The short follow-up might have been insufficient to detect long-term changes in allograft tissue, renal function, and proteinuria.

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Resumo Introdução: A fibrose renal é o desfecho de um processo iniciado no transplante, com reperfusão, isquemia e inflamação precoce, que progride ao longo do tempo com fenômenos imunológicos e não imunológicos. A identificação de marcadores morfológicos e a intervenção precoce poderiam melhorar a função e a sobrevida do enxerto. Objetivo: Avaliar a correlação entre intensidade e especificidade de anticorpos anti-HLA pré-transplante alterações histológicas do enxerto renal, de forma a identificar fatores de risco ou marcadores de disfunção precoces do aloenxerto. Métodos: O presente estudo incluiu uma coorte retrospectiva de receptores de transplante renal sensibilizados com anticorpos anti-HLA no pré-transplante submetidos a biópsia de enxerto nos primeiros dois anos após o transplante. Os grupos foram divididos em função da especificidade dos anticorpos anti-HLA: sem anticorpos doador-específicos (não-DSA, n = 29) e com anticorpos doador-específicos (DSA+, n = 16). Alterações histológicas do enxerto renal, função renal e proteinúria foram analisados. Resultados: Os dois grupos tinham características gerais semelhantes, exceto pela dose mais elevada de timoglobulina administrada nos indivíduos do grupo DSA+ (p < 0,05). O grupo não-DSA teve escores mais elevados de glomeruloesclerose, inflamação intersticial (i) e fibrose intersticial (ci) (p < 0,05), além de maior incidência de rejeição celular aguda (RCA). Não foi observada diferença estatística na incidência de rejeição mediada por anticorpos, função renal ou proteinúria durante o seguimento. Discussão e Conclusões: A diferença nos escores de inflamação e fibrose intersticial pode estar associada à maior incidência de RCA e nefropatia por poliomavírus no grupo não-DSA. Devemos considerar ainda o efeito protetor das doses mais elevadas de timoglobulina na redução da lesão por isquemia-reperfusão no grupo DSA+. O curto período de seguimento pode ter sido insuficiente para detectar alterações de longo prazo no tecido do aloenxerto, função renal e proteinúria.

Asunto(s)

Humanos , Masculino , Femenino , Persona de Mediana Edad , Trasplante de Riñón/efectos adversos , Receptores de Trasplantes , Rechazo de Injerto/inmunología , Antígenos HLA/inmunología , Riñón/inmunología , Anticuerpos/sangre , Proteinuria/diagnóstico , Factores de Tiempo , Biopsia , Fibrosis/etiología , Daño por Reperfusión/prevención & control , Estudios Retrospectivos , Terapia de Inmunosupresión/métodos , Resultado del Tratamiento , Progresión de la Enfermedad , Periodo Preoperatorio , Rechazo de Injerto/patología , Riñón/irrigación sanguínea , Especificidad de Anticuerpos

RESUMEN

Sixty hundred and forty-one Brazilian individuals from the north and northwestern state of Paraná, southern Brazil, were selected for the study. The HLA-A, -B, -DRB1, -DQA1, and -DQB1 genotyping were performed using rSSO and Micro SSP analysis. These genotype data are available in the Allele Frequencies Net Database under the population name "Brazil Paraná Caucasian" number "AFND3618".

Asunto(s)

Genotipo , Antígenos HLA-A/genética , Antígenos HLA-B/genética , Cadenas alfa de HLA-DQ/genética , Cadenas beta de HLA-DQ/genética , Cadenas HLA-DRB1/genética , Brasil , Femenino , Técnicas de Genotipaje , Humanos , Masculino

RESUMEN

Abstract Objective: To compare soluble HLA-C and HLA-DR molecules present in the plasma of orofacial cleft and non-orofacial cleft populations. Material and Methods: Orofacial cleft patients were recruited using an accidental sampling approach (n=15). Peripheral blood was collected from the participants and processed for Enzyme Linked Immunosorbent Assay (ELISA) against HLA-C and HLA-DR with specific antibodies. The absorbance was calculated utilizing ELISA reader. Data were statistically analyzed using an independent t-test to compare the disease and control groups. Results: The levels of soluble HLA-C and HLA-DR were significantly higher in the diseased group compared to the control group (p<0.05). Conclusion: The role of HLA molecules in non-communicable disease and congenital anomalies, particularly orofacial cleft, remains speculative despite the positive results of this study and those of previous investigations. It suggests that the variables examined may affect specific pathways involved in the pathogenesis of orofacial cleft, and predispose the individuals concerned to the oral cleft.

Asunto(s)

Humanos , Femenino , Niño , Adolescente , Antígenos HLA-C , Antígenos HLA-DR , Estudios de Casos y Controles , Patogenesia Homeopática , Labio Leporino/patología , Ensayo de Inmunoadsorción Enzimática , Interpretación Estadística de Datos , Indonesia