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1.
Healthcare (Basel) ; 11(21)2023 Oct 26.
Artículo en Inglés | MEDLINE | ID: mdl-37957973

RESUMEN

Policy diffusion is the process in which an innovation is communicated over time through various channels among the members of a social system. It is a special type of communication, in that the messages are concerned with new ideas. Diffusion theory or diffusion of innovations is the theoretical framework utilized in this study to compare successful programs aimed at providing health care for the homeless population. This study examines the Crisis Outreach Response and Engagement (CORE) program in Hawaii and explains how the diffusion innovation theory and programs in other states can be used to develop policies and processes to successfully address the medical and crisis intervention needs of the homeless on O'ahu. The study also includes suggested recommendations and strategies for the CORE program.

2.
Vaccine ; 40(47): 6740-6746, 2022 11 08.
Artículo en Inglés | MEDLINE | ID: mdl-36220716

RESUMEN

BACKGROUND: BPZE1 is a live, attenuated pertussis vaccine derived from B. pertussis strain Tohama I modified by genetic removal or inactivation of 3 B. pertussis toxins: pertussis toxin, dermonecrotic toxin, and tracheal cytotoxin. This Phase 2a study evaluated the safety and immunogenicity of liquid or lyophilized BPZE1 vaccine administered intranasally by needleless tuberculin syringe or mucosal atomization device (VaxINatorTM) at two dose levels. METHODS: Fifty healthy male and non-pregnant female participants 18-49 years of age were enrolled. Participants were randomized 3:3:3:1 to a single lyophilized dose of 107 colony forming units (CFU) BPZE1, 109 CFU BPZE1, placebo via VaxINator device, or a single liquid dose of 109 CFU BPZE1 via tuberculin syringe. Reactogenicity was assessed for 14 days. Blood was obtained pre-vaccination; on Day 8 (safety); and on Days 15, 29, and 181 (immunogenicity). Nasal wick and swab samples were obtained at baseline and on Days 29 and 181 for assessment of mucosal antibody responses and clearance of BPZE1. RESULTS: Across all groups, 35/50 (70 %) experienced at least one local adverse event (AE) and 31/50 (62 %) experienced at least one systemic AE, with similar AE frequencies observed between the highest 109 CFU BPZE1 and placebo groups. There were no severe or serious AEs during the study. At Day 29, seroconversion (≥2-fold rise from baseline in serum IgG or IgA) to at least 2 pertussis antigens was observed in 73 % in the 109 CFU BPZE1 VaxINator group, 60 % in the 109 CFU BPZE1 group delivered via tuberculin syringe, 27 % of participants in the 107 CFU BPZE1 VaxINator group, and 20 % in the placebo VaxINator group. No participants were colonized with BPZE1 at Day 29 post vaccination. DISCUSSION: Lyophilized BPZE1 vaccine was well tolerated and immunogenic at the highest dose (109 CFU) delivered intranasally by VaxINator device and was not associated with any SAEs or prolonged shedding of BPZE1. Further evaluation of BPZE1 is warranted.


Asunto(s)
Vacuna contra la Tos Ferina , Tos Ferina , Adulto , Masculino , Femenino , Humanos , Vacuna contra la Tos Ferina/efectos adversos , Bordetella pertussis , Tos Ferina/prevención & control , Tuberculina , Administración Intranasal , Vacunas Atenuadas , Inmunogenicidad Vacunal
3.
Vet Clin North Am Equine Pract ; 37(2): 339-366, 2021 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-34243877

RESUMEN

Selected emergency conditions of male and female reproductive tracts in horses are described, including injuries affecting the external genitalia of male horses and emergent conditions arising during gestation in mares. Conditions affecting male horses are discussed in the context of breeding stallions, but kicks or other mechanisms of trauma in the groin can also affect geldings. Priapism, paraphimosis, trauma to the scrotum and testicles, and penile injury are discussed. In mares, traumatic vestibular injury, placentitis, hydropsic conditions, prepubic tendon and abdominal wall compromise, and uterine torsion are included. Clinical recognition of the problem, diagnostic procedures, and treatments are summarized.


Asunto(s)
Enfermedades de los Caballos/diagnóstico , Parafimosis/veterinaria , Priapismo/veterinaria , Reproducción , Animales , Cruzamiento , Urgencias Médicas/veterinaria , Femenino , Genitales Femeninos/lesiones , Genitales Masculinos/lesiones , Enfermedades de los Caballos/terapia , Caballos , Masculino , Parafimosis/diagnóstico , Parafimosis/terapia , Embarazo , Priapismo/diagnóstico , Priapismo/terapia , Heridas y Lesiones/veterinaria
4.
Vet Clin North Am Equine Pract ; 37(2): 367-405, 2021 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-34243878

RESUMEN

Selected conditions affecting broodmares are discussed, including arterial rupture, dystocia, foal support with ex utero intrapartum treatment, uterine prolapse, postpartum colic, the metritis/sepsis/systemic inflammatory response syndrome complex, and retained fetal membranes. Postpartum colic beyond third-stage labor contractions should prompt comprehensive evaluation for direct injuries to the reproductive tract or indirect injury of the intestinal tract. Mares with perforation or rupture of the uterus are typically recognized 1 to 3 days after foaling, with depression, fever, and leukopenia; laminitis and progression to founder can be fulminant. The same concerns are relevant in mares with retention of fetal membranes.


Asunto(s)
Distocia/veterinaria , Enfermedades de los Caballos/diagnóstico por imagen , Parálisis de la Parturienta/diagnóstico por imagen , Retención de la Placenta/veterinaria , Reproducción , Prolapso Uterino/veterinaria , Animales , Distocia/diagnóstico por imagen , Distocia/terapia , Diagnóstico por Imagen de Elasticidad/veterinaria , Urgencias Médicas/veterinaria , Membranas Extraembrionarias/diagnóstico por imagen , Femenino , Hemorragia/veterinaria , Enfermedades de los Caballos/terapia , Caballos , Parálisis de la Parturienta/terapia , Parto , Retención de la Placenta/diagnóstico por imagen , Retención de la Placenta/terapia , Periodo Posparto , Embarazo , Prolapso Uterino/diagnóstico por imagen , Prolapso Uterino/terapia , Útero/diagnóstico por imagen
5.
Virology ; 555: 71-77, 2021 03.
Artículo en Inglés | MEDLINE | ID: mdl-33454559

RESUMEN

This review summarizes the presentations given at the 22nd International conference on Emerging Infectious Diseases in the Pacific Rim. The purpose of this annual meeting is to foster international collaborations and address important public health issues in the Asia-Pacific region. This meeting was held in Bangkok in February 2020 and focused on emerging virus infections. Unexpectedly, the SARS-CoV-2 pandemic was in the initial stages leading to a special session on COVID-19 in addition to talks on dengue, influenza, hepatitis, AIDS, Zika, chikungunya, rabies, cervical cancer and nasopharyngeal carcinoma.


Asunto(s)
Enfermedades Transmisibles Emergentes , Salud Global , Cooperación Internacional , Asia , COVID-19 , Humanos , Japón , Oceanía , Estados Unidos
6.
J Immunol ; 205(4): 877-882, 2020 08 15.
Artículo en Inglés | MEDLINE | ID: mdl-32769142

RESUMEN

Despite high vaccine coverage in many parts of the world, pertussis is resurging in a number of areas in which acellular vaccines are the primary vaccine administered to infants and young children. This is attributed in part to the suboptimal and short-lived immunity elicited by acellular pertussis vaccines and to their inability to prevent nasal colonization and transmission of the etiologic agent Bordetella pertussis In response to this escalating public health concern, the National Institute of Allergy and Infectious Diseases held the workshop "Overcoming Waning Immunity in Pertussis Vaccines" in September 2019 to identify issues and possible solutions for the defects in immunity stimulated by acellular pertussis vaccines. Discussions covered aspects of the current problem, gaps in knowledge and possible paths forward. This review summarizes presentations and discussions of some of the key points that were raised by the workshop.


Asunto(s)
Vacuna contra la Tos Ferina/inmunología , Tos Ferina/inmunología , Animales , Bordetella pertussis/inmunología , Humanos , National Institute of Allergy and Infectious Diseases (U.S.) , Estados Unidos , Vacunas Acelulares/inmunología
7.
Am J Reprod Immunol ; 82(2): e13145, 2019 08.
Artículo en Inglés | MEDLINE | ID: mdl-31087434

RESUMEN

PROBLEM: Progestins are immunomodulatory in a variety of species. In the horse, the most commonly administered synthetic progestin is altrenogest (ALT), but its effect on the immune system of the non-pregnant mare is unknown. METHODS: Peripheral blood mononuclear cells (PBMCs) from diestrous mares were incubated with varying concentrations of progesterone (P4) or ALT to assess intracellular production of IFNγ and the expression of select cytokines. Additionally, ten mares received either ALT or VEH daily utilizing a switchback design beginning on the day of ovulation and continuing for 7 days. Circulating PBMCs and endometrial biopsies were obtained to assess the production and expression of the same cytokines. RESULTS: In vitro, both P4 and ALT caused a dose-dependent decrease in intracellular IFNγ in PBMCs. P4 caused a dose-dependent decrease in the expression of IFNγ, IL-10 and IL-4, while ALT caused an increase in the expression of IL-6 and IL-1ß in PBMCs. In vivo, ALT suppressed the intracellular levels of IFNγ in PBMCs on d6. While control mares experienced a decrease in IL-1ß expression from d0 to d6, ALT-treated mares did not. In the endometrium, ALT increased the expression of IL-1RN and IFNγ in comparison with VEH-treated mares. CONCLUSION: P4 and ALT appear to alter the immune system of the non-pregnant mare both systemically in addition to locally within the endometrium. Further research is necessary to determine the pathways through which this synthetic progestin functions on the immune system of the horse, and the consequences it may have.


Asunto(s)
Endometrio/inmunología , Caballos/inmunología , Leucocitos Mononucleares/efectos de los fármacos , Preñez/inmunología , Acetato de Trembolona/análogos & derivados , Animales , Endometrio/metabolismo , Femenino , Interferón gamma/metabolismo , Interleucina-10/metabolismo , Interleucina-1beta/metabolismo , Interleucina-4/metabolismo , Interleucina-6/metabolismo , Leucocitos Mononucleares/inmunología , Leucocitos Mononucleares/metabolismo , Ovulación , Embarazo , Preñez/metabolismo , Progesterona/sangre , Receptores de Glucocorticoides/metabolismo , Acetato de Trembolona/sangre , Acetato de Trembolona/farmacología
8.
Vaccines (Basel) ; 7(2)2019 Apr 02.
Artículo en Inglés | MEDLINE | ID: mdl-30987042

RESUMEN

The 20th International Conference on Emerging Infectious Diseases in the Pacific Rim to3ok place in Shenzhen, China on January 8⁻9, 2018 followed by meetings of the acquired immunodeficiency syndrome (AIDS)/immunology, acute respiratory infections, cancer, hepatitis, and viral diseases panels on January 10⁻11. The conference was organized as part of the United States-Japan Cooperative Medical Sciences Program (USJCMSP) by the Japan Agency for Medical Research and Development (AMED) and the U.S. National Institutes of Health (NIH) and was locally hosted by the Shenzhen Third People's Hospital and the Chinese Academy of Sciences (CAS) Institute of Microbiology. The conference provides the basis for networking and fostering of collaboration opportunities between researchers in Southeast Asia and the United States based on the scientific and interactive platform of the USJCMSP and takes place in the region on an annual basis. This report summarizes the discussions and conclusions from the conference.

9.
Clin Vaccine Immunol ; 24(7)2017 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-28490424

RESUMEN

Since the middle of the 20th century, vaccines have made a significant public health impact by controlling infectious diseases globally. Although long-term protection has been achieved with some vaccines, immunity wanes over time with others, resulting in outbreaks or epidemics of infectious diseases. Long-term protection against infectious agents that have a complex life cycle and antigenic variation remains a key challenge. Novel strategies to characterize the short- and long-term immune responses to vaccines and to induce immune responses that mimic natural infection have recently emerged. New technologies and approaches in vaccinology, such as adjuvants, delivery systems, and antigen formulations, have the potential to elicit more durable protection and fewer adverse reactions; together with in vitro systems, these technologies have the capacity to model and accelerate vaccine development. The National Institute of Allergy and Infectious Diseases (NIAID) held a workshop on 19 September 2016 that focused on waning immunity to selected vaccines (for Bordetella pertussis, Salmonella enterica serovar Typhi, Neisseria meningitidis, influenza, mumps, and malaria), with an emphasis on identifying knowledge gaps, future research needs, and how this information can inform development of more effective vaccines for infectious diseases.


Asunto(s)
Vacunas Bacterianas/inmunología , Inmunidad Celular , Inmunidad Humoral , Vacunas contra la Malaria/inmunología , Vacunas Virales/inmunología , Adyuvantes Inmunológicos/administración & dosificación , Vacunas Bacterianas/aislamiento & purificación , Portadores de Fármacos , Sistemas de Liberación de Medicamentos , Educación , Humanos , Vacunas contra la Malaria/aislamiento & purificación , National Institute of Allergy and Infectious Diseases (U.S.) , Factores de Tiempo , Estados Unidos , Vacunas Virales/aislamiento & purificación
10.
J Immunol ; 192(5): 2156-66, 2014 Mar 01.
Artículo en Inglés | MEDLINE | ID: mdl-24489092

RESUMEN

CD4(+) T follicular helper cells (TFH) are critical for the formation and function of B cell responses to infection or immunization, but also play an important role in autoimmunity. The factors that contribute to the differentiation of this helper cell subset are incompletely understood, although several cytokines including IL-6, IL-21, and IL-12 can promote TFH cell formation. Yet, none of these factors, nor their downstream cognate STATs, have emerged as nonredundant, essential drivers of TFH cells. This suggests a model in which multiple factors can contribute to the phenotypic characteristics of TFH cells. Because type I IFNs are often generated in immune responses, we set out to investigate whether these factors are relevant to TFH cell differentiation. Type I IFNs promote Th1 responses, thus one possibility was these factors antagonized TFH-expressed genes. However, we show that type I IFNs (IFN-α/ß) induced B cell lymphoma 6 (Bcl6) expression, the master regulator transcription factor for TFH cells, and CXCR5 and programmed cell death-1 (encoded by Pdcd1), key surface molecules expressed by TFH cells. In contrast, type I IFNs failed to induce IL-21, the signature cytokine for TFH cells. The induction of Bcl6 was regulated directly by STAT1, which bound to the Bcl6, Cxcr5, and Pdcd1 loci. These data suggest that type I IFNs (IFN-α/ß) and STAT1 can contribute to some features of TFH cells but are inadequate in inducing complete programming of this subset.


Asunto(s)
Proteínas de Unión al ADN/inmunología , Interferón Tipo I/inmunología , Factor de Transcripción STAT1/inmunología , Linfocitos T Colaboradores-Inductores/inmunología , Animales , Citocinas/biosíntesis , Citocinas/genética , Citocinas/inmunología , Proteínas de Unión al ADN/biosíntesis , Proteínas de Unión al ADN/genética , Regulación de la Expresión Génica/fisiología , Interferón Tipo I/biosíntesis , Interferón Tipo I/genética , Ratones , Ratones Noqueados , Receptor de Muerte Celular Programada 1/genética , Receptor de Muerte Celular Programada 1/inmunología , Proteínas Proto-Oncogénicas c-bcl-6 , Sitios de Carácter Cuantitativo/fisiología , Receptores CXCR5/genética , Receptores CXCR5/inmunología , Factor de Transcripción STAT1/genética , Factor de Transcripción STAT1/metabolismo , Linfocitos T Colaboradores-Inductores/citología , Linfocitos T Colaboradores-Inductores/metabolismo
11.
Trends Immunol ; 34(5): 200-7, 2013 May.
Artículo en Inglés | MEDLINE | ID: mdl-23395212

RESUMEN

CD4(+) T helper (Th) cells play an instrumental role in orchestrating adaptive immune responses to invading pathogens through their ability to differentiate into specialized effector subsets. Part of this customized response requires the development of T follicular helper (Tfh) cells, which provide help to B cells for the generation of germinal centers (GCs) and long-term protective humoral responses. Although initially viewed as terminally differentiated, we now recognize that Th cell subsets, including Tfh cells, display substantial flexibility and overlap in their characteristics. In this review, we highlight advances in our understanding of Tfh cell development, cytokine production, and the potential plasticity that allows Tfh cells to possess characteristics of other effector Th cell populations.


Asunto(s)
Linfocitos B/inmunología , Citocinas/inmunología , Centro Germinal/inmunología , Subgrupos de Linfocitos T/inmunología , Linfocitos T Colaboradores-Inductores/inmunología , Animales , Diferenciación Celular , Linaje de la Célula , Epigénesis Genética/inmunología , Humanos , Memoria Inmunológica , Inmunomodulación
13.
Immunity ; 35(6): 919-31, 2011 Dec 23.
Artículo en Inglés | MEDLINE | ID: mdl-22195747

RESUMEN

Follicular helper T (Tfh) cells comprise an important subset of helper T cells; however, their relationship with other helper lineages is incompletely understood. Herein, we showed interleukin-12 acting via the transcription factor STAT4 induced both Il21 and Bcl6 genes, generating cells with features of both Tfh and Th1 cells. However, STAT4 also induced the transcription factor T-bet. With ChIP-seq, we defined the genome-wide targets of T-bet and found that it repressed Bcl6 and other markers of Tfh cells, thereby attenuating the nascent Tfh cell-like phenotype in the late phase of Th1 cell specification. Tfh-like cells were rapidly generated after Toxoplasma gondii infection in mice, but T-bet constrained Tfh cell expansion and consequent germinal center formation and antibody production. Our data argue that Tfh and Th1 cells share a transitional stage through the signal mediated by STAT4, which promotes both phenotypes. However, T-bet represses Tfh cell functionalities, promoting full Th1 cell differentiation.


Asunto(s)
Diferenciación Celular , Células TH1/citología , Células TH1/inmunología , Animales , Linfocitos T CD4-Positivos/inmunología , Linfocitos T CD4-Positivos/metabolismo , Linfocitos T CD4-Positivos/parasitología , Proteínas de Unión al ADN/genética , Regulación de la Expresión Génica/efectos de los fármacos , Inmunofenotipificación , Interferón gamma/metabolismo , Interleucina-12/farmacología , Ratones , Ratones Endogámicos C57BL , Ratones Transgénicos , Proteínas Proto-Oncogénicas c-bcl-6 , Factor de Transcripción STAT4/metabolismo , Proteínas de Dominio T Box/metabolismo , Linfocitos T Colaboradores-Inductores/citología , Linfocitos T Colaboradores-Inductores/inmunología , Linfocitos T Colaboradores-Inductores/metabolismo , Células TH1/metabolismo , Toxoplasma
14.
Immunity ; 35(4): 622-32, 2011 Oct 28.
Artículo en Inglés | MEDLINE | ID: mdl-22018472

RESUMEN

Follicular T helper (Tfh) cells provide critical help to B cells for germinal center (GC) formation. Mutations affecting SLAM-associated protein (SAP) prevent GC formation because of defective T cell-B cell interactions, yet effects on Tfh cell differentiation remain unclear. We describe the in vitro differentiation of functionally competent "Tfh-like" cells that expressed interleukin-21, Tfh cell markers, and Bcl6 and rescued GC formation in SAP-deficient hosts better than other T helper (Th) cells. SAP-deficient Tfh-like cells appeared virtually indistinguishable from wild-type, yet failed to support GCs in vivo. Interestingly, both Tfh-like and in vivo-derived Tfh cells could produce effector cytokines in response to polarizing conditions. Moreover, Th1, Th2, and Th17 cells could be reprogrammed to obtain Tfh cell characteristics. ChIP-Seq analyses revealed positive epigenetic markings on Tbx21, Gata3, and Rorc in Tfh-like and ex vivo Tfh cells and on Bcl6 in non-Tfh cells, supporting the concept of plasticity between Tfh and other Th cell populations.


Asunto(s)
Diferenciación Celular , Epigénesis Genética , Linfocitos T Colaboradores-Inductores/citología , Linfocitos T Colaboradores-Inductores/inmunología , Animales , Células Cultivadas , Proteínas de Unión al ADN/inmunología , Centro Germinal/citología , Centro Germinal/inmunología , Interleucinas/biosíntesis , Péptidos y Proteínas de Señalización Intracelular/deficiencia , Péptidos y Proteínas de Señalización Intracelular/metabolismo , Ratones , Ratones Endogámicos C57BL , Ratones Noqueados , Proteínas Proto-Oncogénicas c-bcl-6 , Proteína Asociada a la Molécula de Señalización de la Activación Linfocitaria
15.
Blood ; 116(17): 3120-1, 2010 Oct 28.
Artículo en Inglés | MEDLINE | ID: mdl-21030566

RESUMEN

Recent data from mouse models suggest that some phenotypes of X-linked lymphoproliferative disease (XLP) result from impaired T:B-cell interactions.Hislop and colleagues now provide evidence that this may contribute to abnormal responses to Epstein-Barr virus (EBV) in XLP.

16.
Immunity ; 32(6): 828-39, 2010 Jun 25.
Artículo en Inglés | MEDLINE | ID: mdl-20605486

RESUMEN

Although the cellular concentration of miRNAs is critical to their function, how miRNA expression and abundance are regulated during ontogeny is unclear. We applied miRNA-, mRNA-, and ChIP-Seq to characterize the microRNome during lymphopoiesis within the context of the transcriptome and epigenome. We show that lymphocyte-specific miRNAs are either tightly controlled by polycomb group-mediated H3K27me3 or maintained in a semi-activated epigenetic state prior to full expression. Because of miRNA biogenesis, the cellular concentration of mature miRNAs does not typically reflect transcriptional changes. However, we uncover a subset of miRNAs for which abundance is dictated by miRNA gene expression. We confirm that concentration of 5p and 3p miRNA strands depends largely on free energy properties of miRNA duplexes. Unexpectedly, we also find that miRNA strand accumulation can be developmentally regulated. Our data provide a comprehensive map of immunity's microRNome and reveal the underlying epigenetic and transcriptional forces that shape miRNA homeostasis.


Asunto(s)
Epigénesis Genética , Regulación de la Expresión Génica/genética , Linfocitos , Linfopoyesis/genética , MicroARNs/genética , Animales , Expresión Génica , Humanos , Ratones , Reacción en Cadena de la Polimerasa de Transcriptasa Inversa
17.
Immunity ; 32(2): 253-65, 2010 Feb 26.
Artículo en Inglés | MEDLINE | ID: mdl-20153220

RESUMEN

CD4(+) T cells deficient in signaling lymphocyte activation molecule (SLAM)-associated protein (SAP) exhibit a selective impairment in adhesion to antigen-presenting B cells but not dendritic cells (DCs), resulting in defective germinal center formation. However, the nature of this selective adhesion defect remained unclear. We found that whereas T cell:DC interactions were primarily integrin dependent, T cell:B cell interactions had both an early integrin-dependent phase and a sustained phase that also required SAP. We further found that the SLAM family member CD84 was required for prolonged T cell:B cell contact, optimal T follicular helper function, and germinal center formation in vivo. Moreover, both CD84 and another SLAM member, Ly108, mediated T cell adhesion and participated in stable T cell:B cell interactions in vitro. Our results reveal insight into the dynamic regulation of T cell:B cell interactions and identify SLAM family members as critical components of sustained T cell:B cell adhesion required for productive humoral immunity.


Asunto(s)
Linfocitos B/metabolismo , Adhesión Celular/inmunología , Centro Germinal/metabolismo , Péptidos y Proteínas de Señalización Intracelular/metabolismo , Linfocitos T/metabolismo , Animales , Antígenos CD/genética , Antígenos CD/inmunología , Antígenos CD/metabolismo , Antígenos Ly/inmunología , Antígenos Ly/metabolismo , Linfocitos B/inmunología , Linfocitos B/patología , Adhesión Celular/genética , Diferenciación Celular/genética , Diferenciación Celular/inmunología , Proliferación Celular , Células Cultivadas , Centro Germinal/patología , Interferón gamma/metabolismo , Interleucinas/metabolismo , Péptidos y Proteínas de Señalización Intracelular/genética , Péptidos y Proteínas de Señalización Intracelular/inmunología , Activación de Linfocitos/genética , Ratones , Ratones Endogámicos C57BL , Ratones Noqueados , Receptores de Superficie Celular/genética , Receptores de Superficie Celular/inmunología , Receptores de Superficie Celular/metabolismo , Proteína Asociada a la Molécula de Señalización de la Activación Linfocitaria , Familia de Moléculas Señalizadoras de la Activación Linfocitaria , Miembro 1 de la Familia de Moléculas Señalizadoras de la Activación Linfocitaria , Linfocitos T/inmunología , Linfocitos T/patología
18.
Blood ; 108(12): 3769-76, 2006 Dec 01.
Artículo en Inglés | MEDLINE | ID: mdl-16896156

RESUMEN

Our previous results demonstrated that B cells from a patient (pt1) with non-X-linked hyper-IgM syndrome (HIGM) possess an atypical CD23(lo) phenotype that is unaffected by CD40-mediated activation. To investigate the molecular mechanism underlying defective CD23 expression in pt1 B cells, we used lymphoblastoid cell lines that express LMP1 under the control of a tetracycline-inducible promoter (LCL(tet)). Our analysis revealed that the CD23(lo) phenotype in the pt1-LCL(tet) cells is a direct consequence of diminished CD23 transcription. We demonstrate a marked decrease in c-Rel-containing complexes that bind to the proximal CD23a/b promoters in pt1-LCL(tet) extracts, resulting from an overall lower expression of c-Rel in pt1-LCL(tet) cells. Analysis of c-Rel mRNA revealed relatively equal amounts in pt1-LCL(tet) and control LCL(tet) cells, indicating that diminished c-Rel protein expression is unrelated to decreased transcription. Finally, a critical role for c-Rel in CD23 regulation was demonstrated by effectively altering c-Rel expression that resulted in the direct modulation of CD23 surface expression. Collectively, these findings demonstrate that low levels of c-Rel are the underlying cause of aberrant CD23 expression in pt1 B cells and are likely to play a critical role in the pathophysiology of this form of HIGM.


Asunto(s)
Linfocitos B/metabolismo , Regulación de la Expresión Génica , Síndrome de Inmunodeficiencia con Hiper-IgM Tipo 1/metabolismo , Proteínas Proto-Oncogénicas c-rel/biosíntesis , Receptores de IgE/biosíntesis , Linfocitos B/patología , Línea Celular Transformada , Humanos , Síndrome de Inmunodeficiencia con Hiper-IgM Tipo 1/genética , Síndrome de Inmunodeficiencia con Hiper-IgM Tipo 1/patología , Síndrome de Inmunodeficiencia con Hiper-IgM Tipo 1/fisiopatología , Regiones Promotoras Genéticas , Proteínas Proto-Oncogénicas c-rel/genética , Receptores de IgE/genética , Síndrome , Transcripción Genética
19.
Vet Clin North Am Equine Pract ; 22(2): 519-52, x, 2006 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-16882486
20.
J Leukoc Biol ; 78(3): 620-9, 2005 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-15961576

RESUMEN

Our previous investigation of a patient (pt1) with non-X-linked hyper-immunoglobulin M syndrome revealed a CD40-mediated defect in B cell activation that resulted in low CD23 expression and absence of germ-line transcription and class-switch recombination. These deficiencies were complemented in vitro by a high threshold of sustained signaling through CD40. To further analyze the signaling defect in pt1 B cells, two types of Epstein-Barr virus lymphoblastoid cell lines (LCLs) were generated that either constitutively expressed the viral transforming protein latent membrane protein-1 (LMP1; pt1-LCL) or expressed it under the control of a tet-inducible promoter (pt1-LCL(tet)). Because LMP1 signals through the CD40 pathway, the pt1-LCL and pt1-LCL(tet) lines allow comparison of downstream functions in response to either constitutive LMP1 signals or regulated LMP1 and CD40 signals. Immortalized pt1-LCLs were initially CD23(lo)/CD38(hi) and reverted to a CD23(hi)/CD38(lo) phenotype upon extended growth in culture, suggesting that the CD40 defect was reversed by selection and/or constitutive expression of LMP1. In contrast, pt1-LCL(tet) cells retained the CD23(lo)/CD38(hi) phenotype after extended periods of culture and failed to up-regulate CD23 in response to CD40 signals. Analysis of pt1-LCL(tet) cells in response to the CD40 signals in the presence or absence of LMP1 revealed that mitogenic activation resulted only from LMP1 and not CD40, indicating a difference in the response of pt1 B cells to these two distinct signals. Together, these data demonstrate that the pt1-LCL(tet) cells maintain the CD40-related defect and provide a unique approach to study the independent effects of LMP1- and CD40-directed signals.


Asunto(s)
Linfocitos B/inmunología , Antígenos CD40/inmunología , Inmunoglobulina M/inmunología , Síndromes de Inmunodeficiencia/inmunología , Proteínas de la Matriz Viral/inmunología , ADP-Ribosil Ciclasa 1/biosíntesis , ADP-Ribosil Ciclasa 1/genética , Linfocitos B/virología , Línea Celular Transformada , Humanos , Inmunoglobulina M/biosíntesis , Fenotipo , Receptores de IgE/biosíntesis , Receptores de IgE/genética , Transducción de Señal/inmunología , Proteínas de la Matriz Viral/genética
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