RESUMEN
OBJECTIVE: Juvenile spondylarthropathies (jSpA) are polygenic and the clustering of disease in families is caused mainly by genetic factors. Our aim was to look for possible associations of other HLA-A and B specificities, MICA and D6S273 microsatellite polymorphisms that might play a role in determining the susceptibility to jSpA. PATIENTS AND METHODS: jSpA were diagnosed in 74 Croatian children, and 169 healthy unrelated individuals served as the control group. HLA class I (A, B) typing of all individuals was performed, and HLA-B7 and HLA-B27 positive subjects were subtyped by PCR-SSP method. MICA and D6S273 microsatellites alleles were analyzed by electrophoresis in an automated sequencer. RESULTS: We identified 26 HLA-B*07 and 31 HLA-B*27 positive patients with jSpA. DNA subtyping of HLA-B*27 specificity demonstrated only two subtypes, B*2702 (19.35%) and B*2705 (80.65%), among jSpA patients. Subtyping analysis of HLA-B*07 gene showed presence of only one subtype, B*0702. The OR for HLA-B*07 was 2.61, while the highest OR for a single HLA specificity was found for HLA-B*27 (OR=5.60). The HLA-B*07/B*27 combination found in six children showed higher risk (OR=14.82), but the combination of specificities: HLA-B*07/HLA-B*27, and D6S273-134 allele demonstrated the highest risk (OR=26.83). The association with D6S273-134 allele was not a result of the linkage disequilibrium with HLA-B*27 specificity (LD=-0.5). CONCLUSION: Our findings provide evidence that HLA-B*27/HLA-B*07 in combination with D6S273-134 allele is associated with increased susceptibility to jSpA in Croatian children.
Asunto(s)
Predisposición Genética a la Enfermedad/genética , Antígenos HLA-B/genética , Antígeno HLA-B27/genética , Espondiloartropatías/genética , Adolescente , Alelos , Estudios de Casos y Controles , Niño , Preescolar , Croacia , Femenino , Frecuencia de los Genes/genética , Antígeno HLA-B7 , Haplotipos/genética , Antígenos de Histocompatibilidad Clase I/genética , Humanos , Desequilibrio de Ligamiento/genética , Masculino , Repeticiones de Microsatélite/genética , Espondiloartropatías/etnologíaRESUMEN
The aim of the present study was to compare haplotypes of the most frequent B*27 alleles among Croatians (B*2702 and *2705) and the rare B*2730 allele. For this purpose, 37 families with members carrying human leukocyte antigen (HLA)-B27 were selected. All individuals were analysed for eight microsatellites (Msats): D6S2927, short tandem repeat - MHC class I-related gene (STR_MICA), D6S2793, D6S2811, tumor necrosis factor a (TNFa), tumor necrosis factor d (TNFd), D6S273 and D6S1014, while individuals carrying the HLA-B27 specificity were subtyped. Of 39 analysed haplotypes, 20 individuals had B*2702, 15 subjects were positive for the B*2705 allele, the B*2730 allele was found in three haplotypes from different families, while one individual carried the B*2703 allele. HLA-A3 and -DRB1*16 were shared by all three B*2730 haplotypes. The DRB1*16 allele was also observed in the majority of B*2702 haplotypes (76.5%), while HLA-A3 was, after HLA-A2, the second most frequent HLA-A specificity in B*2702 haplotypes. No such correlation was found for the B*2705 haplotypes. Msat analysis showed that B*2730 haplotypes also share the same allele at all tested Msats. The D6S2927, D6S2793, MICA and TNFd Msats were not useful in distinguishing B*2702 and B*2705 alleles because D6S2927-213bp, STR_MICA-179bp, D6S2793-206bp, D6S2811-83bp and TNFd-130bp were detected in almost all cases. Conversely, for the TNFa, D6S273 and D6S1014 loci, haplotypes carrying B*2702 and B*2730 shared a single Msat allele in the majority of cases (TNFa-113bp, D6S1014-134bp and D6S273-134bp), which was not observed for B*2705 haplotypes. In conclusion, the similarity between B*2702 and B*2730 DNA sequences as well as their sharing of the same haplotypic combinations corroborates the proposed mechanism of B*2730 evolution from B*2702 by interallelic recombination.
Asunto(s)
Alelos , Antígenos HLA-B/genética , Haplotipos/genética , Repeticiones de Microsatélite/genética , Sitios de Carácter Cuantitativo/genética , Croacia , Evolución Molecular , Familia , Femenino , Antígeno HLA-A3/genética , Antígeno HLA-B27 , Antígenos HLA-DR/genética , Cadenas HLA-DRB1 , Humanos , Masculino , Recombinación Genética/genéticaRESUMEN
With emergence of MHC class I tetramers loaded with CD8+ T-cell viral epitopes, it is possible to study virus-specific CD8 cells in humans during infection and after vaccination. MHC class I tetramers was used to detect the frequency of haemagglutinin (HA)-specific T cells in 26 healthy influenza-vaccinated humans. Peripheral blood was collected before, and 7, 14 and 28 days after vaccination. Four-colour flow cytometry was used for monitoring of vaccine induced T-cell response. In 15 donors, two- to fivefold increase in frequency of HA-specific T cells was observed 7 days after vaccination. In addition, in 12 of these donors, this increase was accompanied with fourfold increase of H1N1 antibody titre. The increase in frequency of HA-specific CD8+/IFN-gamma+ cells was low and peaked 28 days after vaccination in three of the six donors tested. Frequencies of HA-specific CD8+ T cells and antibody titre returned to prevaccination values 1 year after vaccination. Subunit influenza vaccines have the ability to induce HA-specific CD8+ cells. As the immune response to this vaccine decreased significantly after 1 year, our results confirm the importance of annual immunization for adequate protection.
Asunto(s)
Linfocitos T CD8-positivos/inmunología , Linfocitos T CD8-positivos/virología , Antígenos HLA-A/inmunología , Glicoproteínas Hemaglutininas del Virus de la Influenza/inmunología , Subtipo H1N1 del Virus de la Influenza A/inmunología , Vacunas contra la Influenza/inmunología , Péptidos/inmunología , Adulto , Linfocitos T CD8-positivos/citología , Antígeno HLA-A2 , Glicoproteínas Hemaglutininas del Virus de la Influenza/administración & dosificación , Humanos , Vacunas contra la Influenza/administración & dosificación , Recuento de Linfocitos , Persona de Mediana Edad , Neuraminidasa/administración & dosificación , Neuraminidasa/inmunología , Vacunas de Subunidad/administración & dosificación , Vacunas de Subunidad/inmunologíaRESUMEN
Sarcoidosis is an immune-mediated, multiorgan, granulomatous disease triggered by a combination of environmental and genetic factors. Numerous studies have reported about an association of human leukocyte antigen (HLA) alleles with sarcoidosis, with variation of alleles in different ethnic groups. Therefore, we investigated 142 Croatian sarcoidosis patients treated at the University Hospital for Lung Diseases Jordanovac, Zagreb, Croatia. Diagnosis was based on the presence of typical clinical features, chest X-ray findings and biopsy evidence of granuloma. Patients and control subjects (n = 190) were typed for HLA class I antigens by serology, while for HLA class II, they were tested by the polymerase chain reaction-sequence specific primers (PCR-SSP) method. Results indicated that HLA-B8, -DRB1*0301, and -DQB1*0201 positive patients have a significantly higher risk of acute onset of the disease (AOD), radiological stage I erythema nodosum (EN), Löfgren's syndrome, no-medicament therapy, and pulmonary sarcoidosis. On the other hand, the group of non-treated patients (corticosteroids and/or immunosuppressive) showed a significantly lower presence of HLA-B15 antigen in comparison to controls and treated patients (P = 0.0490 and P = 0.0379, respectively) and for DRB1*04 specificity (P = 0.0078 and P = 0.0065, respectively). In the group of patients with AOD, those who were positive for DRB1*16 specificity have a statistically significant chance to develop EN, as opposed to those who are positive for DRB1*15 specificity.
Asunto(s)
Antígenos de Histocompatibilidad Clase II/genética , Antígenos de Histocompatibilidad Clase I/genética , Sarcoidosis Pulmonar/genética , Adulto , Alelos , Estudios de Casos y Controles , Croacia , Femenino , Antígeno HLA-B8/genética , Antígenos HLA-DQ/genética , Antígenos HLA-DR/genética , Cadenas HLA-DRB1 , Haplotipos/genética , Antígenos de Histocompatibilidad Clase I/metabolismo , Antígenos de Histocompatibilidad Clase II/metabolismo , Humanos , Masculino , Persona de Mediana Edad , Sarcoidosis Pulmonar/fisiopatologíaRESUMEN
Finding that estrogen plays an important role in bone homeostasis in men prompted research on relationship of polymorphism at the CYP19 gene and the bone mass. Therefore, influence of 3-bp deletion/insertion polymorphism of CYP19 (TTTA)7 allele on the peak bone mass attainment in males was studied. Fifty-eight unrelated male participants, aged 21-35, were selected depending on the presence of (TTTA)7 (no.=19) or (TTTA)7-3 (no.=39) alleles from the initial cohort of 92 young males. Heterozygotes (TTTA)7/(TTTA)7-3 (no.=13) were not included in the analysis. Serum levels of estradiol, free testosterone, 25-hydroxyvitamin D, bone alkaline phosphatase, osteocalcin, and beta-crosslaps were measured. Bone mass was measured by DXA at the hip and at the spine. (TTTA)7-3 allele was associated with significantly lower femoral neck bone mineral density (BMD) (p=0.02). Logistic regression model indicated strong association of (TTTA)7-3 allele with low BMD in the range of osteopenia/osteoporosis (p=0.014, odds ratio 12.36, confidence intervals 1.65-92.46). In the present study association of 3-bp deletion polymorphism of the (TTTA)7 allele with decreased peak bone mass in males is reported for the first time. However, further studies are necessary to elucidate the functional relevance of this polymorphism.
Asunto(s)
Aromatasa/genética , Densidad Ósea/genética , Intrones , Polimorfismo Genético , Eliminación de Secuencia , Adulto , Fosfatasa Alcalina/metabolismo , Alelos , Aromatasa/metabolismo , Calcifediol/sangre , Croacia , Estradiol/sangre , Femenino , Humanos , Masculino , Osteocalcina/metabolismo , Análisis de Regresión , Testosterona/sangreRESUMEN
Post-traumatic stress disorder (PTSD) is an anxiety disorder that can occur after exposure to extreme traumatic experience such as war trauma, and is accompanied by fear, helplessness or horror. Exposure to trauma can result in immune dysregulation and influence susceptibility to infectious disease as well as vaccine efficacy. The aim of the study was to determine the relation of psychological stress and the immune response to influenza vaccination in combat-related PTSD patients (n = 28). Detection of anti-viral antibody titre was performed by inhibition of haemagglutination assay. Ex vivo tetramer staining of CD8(+) T lymphocytes was used to monitor T cells specific for human leucocyte antigen (HLA)-A*0201-restricted influenza A haemagglutinin antigens before and after vaccination. Twenty patients showed a fourfold antibody titre increase to one or both influenza A viral strains, and 18 of them showed the same response for both influenza B viral strains. Ten of 15 healthy controls showed a fourfold rise in antibody titre to both influenza A viral strains and eight of them showed the same response for both influenza B viral strains. HLA-A*0201(+) PTSD patients (n = 10) showed a significant increase of influenza-specific CD8 T cells after vaccination. Although those PTSD patients had a lower number of influenza-specific CD8(+) T cells before vaccination compared to HLA-A*0201(+) healthy controls (n = 6), there was no difference in influenza A antibody titre between PTSD patients and control subjects before vaccination. The generated humoral and cellular immune response in PTSD patients argues against the hypothesis that combat-related PTSD in war veterans might affect protection following influenza vaccination.
Asunto(s)
Vacunas contra la Influenza/inmunología , Trastornos por Estrés Postraumático/inmunología , Adulto , Anticuerpos Antivirales/biosíntesis , Anticuerpos Antivirales/sangre , Linfocitos T CD8-positivos/inmunología , Femenino , Antígenos HLA-A/análisis , Antígeno HLA-A2 , Humanos , Inmunidad Celular , Virus de la Influenza A/inmunología , Virus de la Influenza B/inmunología , Masculino , Persona de Mediana Edad , Linfocitos T Citotóxicos/inmunología , Vacunación , VeteranosRESUMEN
The aim of this study was to investigate possible differences in the frequencies of alleles at the HLA loci and at microsatellite loci within the HLA region among patients suffering from psoriatic arthritis (PsA) and healthy controls. Fifty-eight Croatian PsA patients (28 male and 30 female) and 157 healthy unrelated controls were typed for HLA alleles (A, B, Cw and DRB1) by the polymerase chain reaction-sequence-specific primers (PCR-SSP) method, while microsatellite alleles (D6S265, D6S273, MHC class I chain-related gene (MICA) and MIB) were analysed by electrophoresis in an ALFexpress sequencer (Pharmacia Biotech, Uppsala, Sweden). The findings from this study were: (1) the frequencies of B*39 and B*57 were significantly increased in PsA patients; (2) differences in the frequencies of B*13 and B*27 were not statistically significant after correction; (3) the B*0702, B*18, and B*38 alleles were decreased in patients only before correction; (4) none of the alleles at other HLA loci tested were associated with PsA in Croatia; (5) polymorphism at D6S265, D6S273, and MIB microsatellites in patients did not show any statistically significant differences when compared to controls; (6) the increase in the MICA-A4 allele frequency in PsA patients was independent of the B*39 and B*57 alleles.
Asunto(s)
Artritis Psoriásica/genética , Antígenos de Histocompatibilidad Clase I/genética , Polimorfismo Genético , Repeticiones de Trinucleótidos , Adulto , Edad de Inicio , Anciano , Alelos , Estudios de Casos y Controles , Croacia , Femenino , Frecuencia de los Genes , Predisposición Genética a la Enfermedad , Antígenos HLA-B/genética , Humanos , Masculino , Persona de Mediana Edad , RiesgoAsunto(s)
Antígeno HLA-B27/genética , Espondilitis Anquilosante/genética , Croacia , Genes MHC Clase I , Antígeno HLA-B27/sangre , Antígeno HLA-B27/clasificación , Prueba de Histocompatibilidad , Humanos , Reacción en Cadena de la Polimerasa , Polimorfismo Conformacional Retorcido-Simple , Espondilitis Anquilosante/sangreRESUMEN
The aim of the study was to evaluate the role of HLA-DRB1 (Human Leukocyte Antigens) matching in corneal transplantation. Fifty-two patients were observed. Low-risk group consisted of 28 patients and high-risk group consisted of 24 patients. All the patients and donors were tissue typed with Polymerase Chain Reaction (PCR) on the HLA-DRB1 gen. The primary corneal disease preceding keratoplasty was keratopathia (15), leucoma (10), keratoconus (7), Re-KPP (6), impending perforation (4), combustio corneae (3), degenerative disorders (2), keratoglobus (1), keratouveitis (1), corneal maculae (1), and corneal melting syndrome (1). The graft rejection frequency was higher in the group of high-risk patients (29%) than in the group of low risk patients (7.1%). The rejection rate of compatible grafts was 37% for high risk and 2% for low risk group, while the rejection rate of incompatible was 44% in high risk and 5% in low risk group. We can conclude that HLA-DRB1 matching does not improve corneal graft survival.
Asunto(s)
Trasplante de Córnea , Antígenos HLA-DR/inmunología , Adolescente , Adulto , Anciano , Anciano de 80 o más Años , Estudios de Casos y Controles , Femenino , Rechazo de Injerto , Cadenas HLA-DRB1 , Prueba de Histocompatibilidad , Humanos , Masculino , Persona de Mediana Edad , Reacción en Cadena de la Polimerasa , Medición de RiesgoRESUMEN
The differences in amino acid residues of HLA-B27 subtypes are minor, but may play role in pathogenesis of ankylosing spondylitis (AS). Aim of this study was to investigate of frequency of B27 subtypes in Croatian AS patients and B27 positive healthy controls. Group of 50 AS patients and 38 B27 positive controls were typed for B27 subtypes by PCR-SSP method. In the group of AS patients we found four subtypes: B*2705 (83.0%), B*2702 (13.2%), while remaining two alleles B*2701 and B*2704 had one individual each. In the group of B27+ controls we also observed B*2705 (76.3%) as most frequent allele while frequency of B*2702 was 21.1%. No significant evidence for association between AS and a particular HLA-B27 subtype in the Croatian population were found.
Asunto(s)
Predisposición Genética a la Enfermedad , Antígeno HLA-B27/genética , Espondilitis Anquilosante/genética , Adulto , Croacia , Femenino , Frecuencia de los Genes , Humanos , Masculino , Persona de Mediana Edad , Polimorfismo GenéticoRESUMEN
We describe for the first time extended haplotypes in a Croatian population. The present study gives the HLA-A, -B, -DRB1, -DQA1 and -DQB1 allele and haplotype frequencies in 105 families with at least two offspring. All individuals were studied by conventional serology for HLA class I antigens (A and B), while class II alleles (DRB1, DQA1, DQB1) were typed using the PCR-SSOP method. HLA genotyping was performed by segregation in all 105 families. For extended haplotype analysis, 420 independent parental haplotypes were included. Fourteen HLA-A, 18 HLA-B, 28 DRB1, 9 DQA1 and 11 DQB1 alleles were found in the studied population. Most of the DRB1 alleles in our population had an exclusive association with one specific DQA1-DQB1 combination. This strong linkage disequilibrium within the HLA class II region is often extended to the HLA-B locus. A total of 10 HLA-A, -B, -DRB1, -DQA1, -DQB1 haplotypes were observed with a frequency
Asunto(s)
Antígenos HLA-A/genética , Antígenos HLA-B/genética , Antígenos HLA-DQ/genética , Antígenos HLA-DR/genética , Polimorfismo Genético , Croacia , Genética de Población , Cadenas alfa de HLA-DQ , Cadenas beta de HLA-DQ , Cadenas HLA-DRB1 , Haplotipos , Humanos , Desequilibrio de Ligamiento , Hibridación de Ácido NucleicoRESUMEN
The HLA class I polymorphism was studied in a sample of the Albanian population. Ninety-three unrelated healthy Albanians were typed for HLA-A, -B and -Cw antigens by standard microlyphocytotoxicity test. The antigens with the highest frequencies were: HLA-A2 (34.4%), A3 (14.5%) and A1 (12.4%); B51 (19.3%), B35 (12.4%) and B18 (10.2%); Cw4 (16.2%), Cw7 (16.2%) and Cw6 (10.8%). The HLA haplotypes with high frequency in Albanians included A2-B51 (4.3%), A2-B18 (2.4%), A2-B35 (2.4%), Cw4-B35 (7.6%), and Cw7-B18 (6.5%), which are not significantly different from the other neighboring populations. Low frequency of HLA-A1-B8 haplotype (1.1%) is noted in the Albanian population. The frequency of HLA-B27 antigen (1.1%) is one of the lowest frequencies observed in Caucasians. Such results are important in studies of HLA-A1-B8, HLA-B27 and disease associations. These findings should be also useful in understanding the origin of Albanians, representing a base for future studies about HLA polymorphism in the Albanian population.
Asunto(s)
Genes MHC Clase I/genética , Polimorfismo Genético , Albania , Humanos , Población Blanca/genéticaRESUMEN
In common with most autoimmune diseases, psoriasis is associated with some HLA antigens. We studied the distribution of HLA antigens in Croatian patients with psoriasis: 108 patients were divided into groups according to family history and age of disease onset. HLA antigens were analyzed serologically and HLA-C alleles were analyzed using polymerase chain reaction. We found significant increases in HLA-A2, -B17, -B37 and -B13 antigens and highly significant increases in HLA-Cw*0602 and DR7 antigens in psoriatic patients compared with controls. Patients with type I psoriasis (early onset, positive family history) showed highly significant associations with Cw*0602 [p < 0.00001; relative risk (RR) = 14.45] and DR7 (p < 0.00001; RR = 15.09) antigens. Patients with type II psoriasis (late onset, no family history) had a significant association with Cw*03 antigen (p = 0.008; RR = 0.17). In conclusion, HLA-B13, -B17, Cw*0602 and -DR7 antigens are associated with a significant risk of psoriasis in the Croatian population and the Cw*0602 allele has the strongest association, especially for type I psoriasis.
Asunto(s)
Antígenos HLA/sangre , Psoriasis/genética , Psoriasis/inmunología , Población Blanca/genética , Adulto , Croacia , Femenino , Antígenos HLA/clasificación , Humanos , Masculino , Reacción en Cadena de la PolimerasaRESUMEN
In this study the immunogenetic relationships among 141 unrelated HLA-B27+ patients with ankylosing spondylitis (AS) and 792 members of their families were studied. Two control groups, with at least one B27+ parent were used (families undergoing transplantation program and triplet families undergoing paternity testing). All subjects were typed for HLA-A and -B antigens by microlyphocytotoxity test (MLCT) on local typing trays. The frequency of HLA-A and -B alleles was equal in the all tested groups. The segregation of all tested genes was regular regarding to the total number of positive and negative siblings, while regarding to the sex of sibs was irregular for HLA-B27 and -B5 gene. The statistical significance (p < 0.05) was found when ratio between B27+ and B27- sons in AS group was compared with the same ration in control families. In AS group was detected statistical significant (p < 0.01) high number of B5+ than B5- daughters and statistical significant (p < 0.05) less number of B5+ sons. HLA-B21 was shown to be decreased among B27+ AS patients. A synergistic effect between additional HLA-B alleles and B27 was not observed. The distribution of B27 haplotypes in AS and control families was similar except for haplotype HLA-A10, B27 which was significant (p < 0.001) less present in AS families.
Asunto(s)
Antígenos HLA/genética , Espondilitis Anquilosante/genética , Pruebas Inmunológicas de Citotoxicidad , Femenino , Antígenos HLA-A/genética , Antígenos HLA-B/genética , Antígeno HLA-B27/genética , Humanos , Masculino , Espondilitis Anquilosante/inmunologíaRESUMEN
The HLA class II alleles (DRB1, DRB3, DRB5, DQA1, and DQB1) and haplotypic associations were studied in the population of the island of Krk using the PCR-SSOP method and the 12th International Histocompatibility Workshop primers and probes. Allele and haplotypic frequencies were compared with the general Croatian population. Significant differences were observed between the population of the island of Krk and Croatians for: a) three broad specificities at DRB1 locus (DRB1*01, *15, and *07), b) one allele at DRB3 locus (DRB3*0301), c) one allele at DQA1 locus (DQA1*0201), d) one allele at DQB1 locus (DQB1*0303). Four unusual haplotypic associations, which have not yet been described in the Croatian population, DRB1*1301-DQA1*0103-DQB1*0607, DRB1*1302-DQA1*0102-DQB1*0605, DRB1*1305-DQA1*0102-DQB1*0605 and DRB1*1305-DQA1*0103-DQB1*0603 were observed in the population from the island of Krk.
Asunto(s)
Frecuencia de los Genes , Antígenos HLA-DQ/genética , Antígenos HLA-DR/genética , Croacia/epidemiología , Haplotipos , Humanos , Reacción en Cadena de la Polimerasa , Polimorfismo GenéticoRESUMEN
The HLA-A*02 allele is the most heterogeneous allele at HLA-A locus with 22 different subtypes so far identified. All of these subtype polymorphisms are located in alpha 1 and alpha 2 domains which are responsible for peptide biding and HLA restricted recognition by T-cell receptor. The aim of the present study was to determine the frequency of different HLA-A*02 alleles in 33 healthy unrelated Croatians. HLA-A*02 subtyping has also been retrospectively performed in 2 recipient-unrelated donor pairs and in 4 recipient-HLA phenotypically identical parent pairs. All subjects, previously typed as HLA-A2 by serology were tested using HLA-A*02 ARMS-PCR kit which discriminates 17 different A*02 alleles. Among 17 A*02 alleles we have found 4 different A*02 subtypes in healthy unrelated Croatians. The most frequent A*02 allele was A*0201 (84%). The frequency of the remaining A*02 alleles were as follows: A*0205 (3%), A*0207 (6%) and A*0213 (6%). Among 6 tested bone-marrow transplantation (BMT) pairs, only one has been found to be A*02 subtype incompatible (A*0201/A*0205). Four different A*02 alleles are found in Croatian population with the predominance of A*0201. However these results suggest that A*02 subtyping is also necessary for optimal matching of HLA-A*02 positive donor-recipient pairs in HLA incompatible BMT.
Asunto(s)
Trasplante de Médula Ósea , Antígenos HLA-A/genética , Prueba de Histocompatibilidad , Donantes de Tejidos , Alelos , Croacia , Femenino , Frecuencia de los Genes , Humanos , MasculinoRESUMEN
The DRB1, DRB3, DRB5, DQA1 and DQB1 allele polymorphisms were analysed in 3 western and 3 eastern villages of the island of Hvar using PCR-SSOP method and 12th International Workshop primers and probes. Three DQB1 alleles (*0304, *0305, *0607) detected in the population of the island of Hvar (HP) have not yet been observed in general Croatian population (GCP). Significant differences were observed between two regions of Hvar for: a) DRB1*0701 allele (p < 0.001), b) DQA1*0201 allele (p < 0.01), and c) DRB1*0101-DQA1*0101-DQB1*0501 haplotypic association (p < 0.05). Two unusual haplotypic associations, which have not yet been described in general Croatian population (GCP), DRB1*0101-DQA1*0102-DQB1*0501 and DRB1*1501-DQA1 *0102-DQB1*0604 were observed in the population from the island of Hvar (HP). Measures of genetic kinship and genetic distances revealed isolation and clusterization which coincides with the known ethnohistorical, as well as biological and biocultural data obtained from a series of previous investigations. The five studied village subpopulations formed two clusters (East-West) to which the far eastern village (with the highest rii of 0.0407) joined later, thus indicating possible impact of historical immigrations from the mainland.
Asunto(s)
Genes MHC Clase II/genética , Variación Genética , Haplotipos , Croacia , HumanosRESUMEN
Several studies of HLA and gluten enteropathy (GE) in European countries have found an association between this disease and certain DR phenotypes. However, no studies of DR phenotypes have been published in GE coming from Croatia. Therefore, we have studied HLA-A, B and DR specificities in 94 unrelated children with GE and in a group of healthy controls. In GE there was significant increase in the frequencies of A1 (61.70% v 24.50%; p < 0.0001) and B8 antigen (70.21% v 20.51%; p < 0.0001) compared with controls. The most frequent DR antigen was HLA-DR3 (87.23% v 18.82% in controls) with the relative risk of 29.65. The distribution of DR phenotypes in GE showed that the most frequent one was DR3/other DR (54.26%) and in decreasing order DR3/DR7 (17.02%), DR3/X (15.96%) and DR5/DR7 (8.51%). These phenotypes account for 95.75% of patients studied. A further 3.19% have DR4/DR5 phenotype. However, due to the frequency of certain antigen in controls, only phenotypes DR3/DR7 (relative risk: 28.92), DR3/X (relative risk: 13.29) and DR3/ other DR (relative risk: 10.04) were significantly associated with GE. The present study emphasizes the importance of studying the HLA-DR phenotypes in patients with GE.
Asunto(s)
Enfermedad Celíaca/inmunología , Antígenos HLA-DR/análisis , Adolescente , Niño , Preescolar , Croacia , Femenino , Antígenos HLA-A/análisis , Antígenos HLA-B/análisis , Humanos , Masculino , Fenotipo , Factores de RiesgoRESUMEN
1. An obligatory step in the biosynthesis of endothelin-1 (ET-1) is the conversion of its inactive precursor, big ET-1, into the mature form by the action of specific, phosphoramidon-sensitive, endothelin converting enzyme(s) (ECE). Disparate effects of big ET-1 and ET-1 on renal tubule function suggest that big ET-1 might directly influence renal tubule function. Therefore, the role of the enzymatic conversion of big ET-1 into ET-1 in eliciting the functional response (generation of 1,2-diacylglycerol) to big ET-1 was studied in the rat proximal tubules. 2. In renal cortical slices incubated with big ET-1, pretreatment with phosphoramidon (an ECE inhibitor) reduced tissue immunoreactive ET-1 to a level similar to that of cortical tissue not exposed to big ET-1. This confirms the presence and effectiveness of ECE inhibition by phosphoramidon. 3. In freshly isolated proximal tubule cells, big ET-1 stimulated the generation of 1,2-diacylglycerol (DAG) in a time- and dose-dependent manner. Neither phosphoramidon nor chymostatin, a chymase inhibitor, influenced the generation of DAG evoked by big ET-1. 4. Big ET-1-dependent synthesis of DAG was found in the brush-border membrane. It was unaffected by BQ123, an ETA receptor antagonist, but was blocked by bosentan, an ETA.B-nonselective endothelin receptor antagonist. 5. These results suggest that the proximal tubule is a site for the direct effect of big ET-1 in the rat kidney. The effect of big ET-1 is confined to the brush-border membrane of the proximal tubule, which may be the site of big ET-1 sensitive receptors.