A majority of Brazilian patients with rheumatoid arthritis HLA-DRB1 alleles carry both the HLA-DRB1 shared epitope and anti-citrunillated peptide antibodies

The objective of the present study was to evaluate the contribution of the shared epitope (SE), the rheumatoid arthritis (RA) protection model, and the occurrence of anti-cyclic citrullinated peptide (anti-CCP) antibodies in RA patients from a genetically diverse population. One hundred and forty Brazilian RA patients and 161 matched controls were typed for HLA-DRB1 alleles using amplified DNA hybridized with sequence-specific oligonucleotide probes or primers. Patients were stratified according to the presence or absence of SE (DRB1*0401, *0404, *0405, *0101, *1001, and *1402), of the DERAA alleles (DRB1*0103, *0402, *1102, *1103, *1301, *1302, and *1304), and X (all other alleles). Anti-CCP antibodies were measured by ELISA. The combined frequency of SE-positive alleles was significantly greater (76.4 vs 23.6%, P < 0.0001) than the controls. The SE/SE and SE/X genotypes were over-represented (P < 0.0001, OR = 6.02) and DERAA/X was under-represented in RA patients (P < 0.001, OR = 0.49), whereas the frequencies of the SE/DERAA, X/X and X/DERAA genotypes were not significantly different from controls. The frequency of anti-CCP antibodies was higher in SE-positive patients than in SE-negative patients (64.6 vs 44.7%, P = 0.03; OR = 2.25). Although the Brazilian population is highly miscegenated, the results of this study support the findings observed in most genetically homogeneous populations with RA; however, they are not mutually exclusive but rather complementary. The participation of DRB1-DERAA alleles in protection against RA was also observed (OR = 0.4; 95%CI = 0.23-0.68).CNPqFAEP

Effect of metabolic control on interferon-gamma and interleukin-10 production by peripheral blood mononuclear cells from type 1 and type 2 diabetic patients

The objective of the present study was to evaluate the production of cytokines, interferon-g (INF-g) and interleukin-10 (IL-10), in cultures of peripheral blood mononuclear cells (PBMC) from type 1 and type 2 diabetic patients and to correlate it with inadequate and adequate metabolic control. We studied 11 type 1 and 13 type 2 diabetic patients and 21 healthy individuals divided into two groups (N = 11 and 10) paired by sex and age with type 1 and type 2 diabetic patients. The PBMC cultures were stimulated with concanavalin-A to measure INF-g and IL-10 supernatant concentration by ELISA. For patients with inadequate metabolic control, the cultures were performed on the first day of hospitalization and again after intensive treatment to achieve adequate control. INF-g levels in the supernatants of type 1 diabetic patient cultures were higher compared to type 2 diabetic patients with adequate metabolic control (P < 0.001). Additionally, INF-g and IL-10 tended to increase the liberation of PBMC from type 1 and 2 diabetic patients with adequate metabolic control (P = 0.009 and 0.09, respectively). The increased levels of INF-g and IL-10 released from PBMC of type 1 and 2 diabetic patients with adequate metabolic control suggest that diabetic control improves the capacity of activation and maintenance of the immune response, reducing the susceptibility to infections

Association of Alport's syndrome with HLA-DR2 antigen in a group of unrelated patients

A few family studies have evaluated HLA antigens in Alport's syndrome; however, there are no large population studies. In the present report, we studied 40 unrelated white patients with Alport's syndrome seen at the Unit of Renal Transplantation, Faculty of Medicine of Ribeirão Preto, São Paulo, Brazil. HLA-A, -B, -DR and -DQ antigens were typed using a complement-dependent microlymphocytotoxicity assay. A control white population (N = 403) from the same geographical area was also typed for HLA antigens. Although the frequencies of HLA-A and -B antigens of patients were not statistically different from controls, the frequency of HLA-DR2 antigen observed in patients (65%) was significantly increased in relation to controls (26%; P<0.001). The relative risk and etiologic fraction for HLA-DR2 antigen were 5.2 and 0.525, respectively. Although few immunological abnormalities have been shown in Alport's syndrome, in this report we emphasize the association of HLA molecules and Alport's syndrome. Besides the well-known inherited molecular defects encoded by type IV collagen genes in Alport's syndrome, the major histocompatibility alleles may be in linkage disequilibrium with these defective collagen gene

Prospective analysis between the therapy of immunosuppressive medication and allogeneic microchimerism after liver transplantation

After liver transplantation, migration of donor-derived hematopoietic cells to recipient can be detected in pheripheral blood. This state is termed microchimerism. The aim of this study was to investigate prospectively the presence of allogeneic microchimerism, the occurrence of acute cellular rejection and the level of immunosuppression in transplanted patients. Microchimerism occurrence between 10 days and 12 months after liver transplantation was analyzed in 47 patients aged between 15 and 65 by a two-stage nested PCR/SSP technique to detect donor MHC HLA-DR gene specifically. A pre-transplant blood sample was colleted from each patient to serve as individual negative control. Microchimerism was demonstrated in 32 (68%) of the 47 patients; of these, only 10 patients (31.2%) presented rejection. Early microchimerism was observed in 25 patients (78.12%) and late microchimerism in 7 patients (21.8%). Among the patients with microchimerism, 14 were given CyA and 18 were given FK506. In the group without microchimerism, 12 patients were given CyA and 03 were given FK506. There was a significant association between the presence of microchimerism and the absence of rejection (p = 0.02) and also between microchimerism and the type of immunosuppression used. Our data indicate that microchimerism and probably differentiation of donor-derived leukocytes can have relevant immunologic effects both in terms of sensitization of recipient and in terms of immunomodulation toward tolerance induction203195198FUNDAÇÃO DE AMPARO À PESQUISA DO ESTADO DE SÃO PAULO - FAPESPnão te

Hla-drb1∗07:01 Allele Is Primarily Associated With The Diego A Alloimmunization In A Brazilian Population

Background The Diego blood group presents a major polymorphic site at Residue 854, causing a proline (Dib antigen) to leucine (Dia antigen) substitution. Dia alloimmunization has been observed among Asian and Native South American populations. Considering that Brazilians represent a genetically diverse population, and considering that we have observed a high incidence of Dia alloimmunization, we typed HLA-DRB1 alleles in these patients and performed in silico studies to investigate the possible associated mechanisms.Study Design and Methods We studied 212 alloimmunized patients, of whom 24 presented immunoglobulin G anti-Dia, 15 received Di(a+) red blood cells and were not immunized, and 1008 were healthy donors. HLA typing was performed using commercial kits. In silico analyses were performed using the TEPITOPEpan software to identify Diego-derived anchor peptide binding to HLA-DRB1 molecules. Residue alignment was performed using the IMGT/HLA for amino acid identity and homology analyses.Results HLA-DRB1∗07:01 allele was overrepresented in Dia-alloimmunized patients compared to nonimmunized patients and to healthy donors. Two motifs were predicted to be potential epitopes for Dia alloimmunization, the WVVKSTLAS motif was predicted to bind several HLA-DR molecules, and the FVLILTVPL motif exhibited highest affinity for the HLA-DRB1∗07:01 molecule. Pocket 4 of the DRB1∗07:01 molecule contained specific residues not found in other HLA-DRB1 molecules, particularly those at Positions 13(Y), 74(Q), and 78(V).Conclusion Individuals carrying the HLA-DRB1∗07:01 allele present an increased risk for Dia alloimmunization. The identification of susceptible individuals and the knowledge of potential sensitization peptides are relevant approaches for transfusion care, diagnostic purposes, and desensitization therapies.541024682476Jay, D., Cantley, L., Structural aspects of the red cell anion exchange protein (1986) Annu Rev Biochem, 55, pp. 511-538Lux, S.E., John, K.M., Kopito, R.R., Cloning and characterization of band 3, the human erythrocyte anion-exchange protein (AE1) (1989) Proc Natl Acad Sci U S A, 86, pp. 9089-9093Tanner, M.J., Martin, P.G., High, S., The complete amino acid sequence of the human erythrocyte membrane anion-transport protein deduced from the cDNA sequence (1988) Biochem J, 256, pp. 703-712Tanner, M.J., The structure and function of band 3 (AE1): Recent developments (review) (1997) Mol Membr Biol, 14, pp. 155-165Bruce, L.J., Ring, S.M., Anstee, D.J., Changes in the blood group Wright antigens are associated with a mutation at amino acid 658 in human erythrocyte band 3: A site of interaction between band 3 and glycophorin A under certain conditions (1995) Blood, 85, pp. 541-547Bruce, L.J., Zelinski, T., Ridgwell, K., The low-incidence blood group antigen, Wda, is associated with the substitution Val557 - >met in human erythrocyte band 3 (AE1) (1996) Vox Sang, 71, pp. 118-120Jarolim, P., Murray, J.L., Rubin, H.L., A Thr552 - >ile substitution in erythroid band 3 gives rise to the Warrior blood group antigen (1997) Transfusion, 37, pp. 398-405Jarolim, P., Murray, J.L., Rubin, H.L., Blood group antigens Rb(a), Tr(a), and Wd(a) are located in the third ectoplasmic loop of erythroid band 3 (1997) Transfusion, 37, pp. 607-615Jarolim, P., Rubin, H.L., Zakova, D., Characterization of seven low incidence blood group antigens carried by erythrocyte band 3 protein (1998) Blood, 92, pp. 4836-4843Daniels, G.L., Anstee, D.J., Cartron, J.P., International Society of Blood Transfusion Working Party on terminology for red cell surface antigens (2001) Vox Sang, 80, pp. 193-197Storry, J.R., Castilho, L., Daniels, G., International Society of Blood Transfusion Working Party on red cell immunogenetics and blood group terminology: Berlin report (2011) Vox Sang, 101, pp. 77-82Baleotti, W., Jr., Rios, M., Reid, M.E., A novel DI∗A allele without the Band 3-Memphis mutation in Amazonian Indians (2003) Vox Sang, 84, pp. 326-330Layrisse, M., Arends, T., The Diego systemSteps in the investigation of a new blood group systemFurther studies (1957) Blood, 12, pp. 115-122Bruce, L.J., Anstee, D.J., Spring, F.A., Band 3 Memphis variant II. Altered stilbene disulfonate binding and the Diego (Dia) blood group antigen are associated with the human erythrocyte band 3 mutation Pro854 - >leu (1994) J Biol Chem, 269, pp. 16155-16158Treml, A., King, K.E., Red blood cell alloimmunization: Lessons from sickle cell disease (2013) Transfusion, 53, pp. 692-695Shariatmadar, S., Pyrsopoulos, N.T., Vincek, V., Alloimmunization to red cell antigens in liver and multivisceral transplant patients (2007) Transplantation, 84, pp. 527-531Moise, K.J., Red blood cell alloimmunization in pregnancy (2005) Semin Hematol, 42, pp. 169-178Nurse, G.T., Jenkins, T., Genetically determined hazards of blood transfusion within and between races (1973) S Afr Med J, 47, pp. 56-61Tormey, C.A., Stack, G., Immunogenicity of blood group antigens: A mathematical model corrected for antibody evanescence with exclusion of naturally occurring and pregnancy-related antibodies (2009) Blood, 114, pp. 4279-4282Giblett, E.R., A critique of the theoretical hazard of inter vs intra-racial transfusion (1961) Transfusion, 1, pp. 233-238Rammensee, H.G., Chemistry of peptides associated with MHC class i and class II molecules (1995) Curr Opin Immunol, 7, pp. 85-96Menconi, F., Osman, R., Monti, M.C., Shared molecular amino acid signature in the HLA-DR peptide binding pocket predisposes to both autoimmune diabetes and thyroiditis (2010) Proc Natl Acad Sci U S A, 107, pp. 16899-16903Singh, A., Sharma, P., Kar, H.K., HLA alleles and amino-acid signatures of the peptide-binding pockets of HLA molecules in vitiligo (2012) J Invest Dermatol, 132, pp. 124-134Picard, C., Frassati, C., Basire, A., Positive association of DRB1 04 and DRB1 15 alleles with Fya immunization in a Southern European population (2009) Transfusion, 49, pp. 2412-2417Noizat-Pirenne, F., Tournamille, C., Bierling, P., Relative immunogenicity of Fya and K antigens in a Caucasian population, based on HLA class II restriction analysis (2006) Transfusion, 46, pp. 1328-1333Zhang, L., Chen, Y., Wong, H.S., TEPITOPEpan: Extending TEPITOPE for peptide binding prediction covering over 700 HLA-DR molecules (2012) Plos One, 7, p. e30483Green, A., The epidemiologic approach to studies of association between HLA and disease. II. Estimation of absolute risks, etiologic and preventive fraction (1982) Tissue Antigens, 19, pp. 259-268Reviron, D., Dettori, I., Ferrera, V., HLA-DRB1 alleles and Jk(a) immunization (2005) Transfusion, 45, pp. 956-959Arnold, P.Y., La Gruta, N.L., Miller, T., The majority of immunogenic epitopes generate CD4+ T cells that are dependent on MHC class II-bound peptide-flanking residues (2002) J Immunol, 169, pp. 739-749Vignali, D.A., Strominger, J.L., Amino acid residues that flank core peptide epitopes and the extracellular domains of CD4 modulate differential signaling through the T cell receptor (1994) J Exp Med, 179, pp. 1945-1956Chiaroni, J., Dettori, I., Ferrera, V., HLA-DRB1 polymorphism is associated with Kell immunisation (2006) Br J Haematol, 132, pp. 374-37

Serum levels of brain-derived neurotrophicfactor correlate with the number of T2 MRI lesions in multiple sclerosis

The objective of the present study was to determine if there is a relationship between serum levels of brain-derived neurotrophic factor (BDNF) and the number of T2/fluid-attenuated inversion recovery (T2/FLAIR) lesions in multiple sclerosis (MS). The use of magnetic resonance imaging (MRI) has revolutionized the study of MS. However, MRI has limitations and the use of other biomarkers such as BDNF may be useful for the clinical assessment and the study of the disease. Serum was obtained from 28 MS patients, 18-50 years old (median 38), 21 women, 0.5-10 years (median 5) of disease duration, EDSS 1-4 (median 1.5) and 28 healthy controls, 19-49 years old (median 33), 19 women. BDNF levels were measured by ELISA. T1, T2/FLAIR and gadolinium-enhanced lesions were measured by a trained radiologist. BDNF was reduced in MS patients (median [range] pg/mL; 1160 [352.6-2640]) compared to healthy controls (1640 [632.4-4268]; P = 0.03, Mann-Whitney test) and was negatively correlated (Spearman correlation test, r = -0.41; P = 0.02) with T2/FLAIR (11-81 lesions, median 42). We found that serum BDNF levels were inversely correlated with the number of T2/FLAIR lesions in patients with MS. BDNF may be a promising biomarker of MS

Quantitative cell-cycle protein expression in oral cancer assessed by computer-assisted system

The knowledge of cell-cycle control has shown that the capacity of malignant growth is acquired by the stepwise accumulation of defects in specific genes regulating cell growth. Histologic diagnosis might be improved by a quantitative evaluation of more specific diagnosis biomarkers, which could help to precisely identify pre-malignant and malignant oral lesions. The aim of the present study is to evaluate whether computer-based quantitative assessment of p53, PCNA and Ki-67 immunohistochemical expression, could be used clinically to foresee the risk of oral malignant transformation. This retrospective study was carried out in ninety-five oral biopsies, 27 were classified as fibrous inflammatory hyperplasia, 40 as leukoplakia and 28 as oral squamous cell carcinoma. Sixteen out of the 40 leukoplakia were diagnosed as non-dysplastic leukoplakia, the other 24 being dysplastic leukoplakia, of which 50.0% were classified as moderate to severe dysplasia. Comparison of the four groups of oral tissues showed significant rises in p53 and Ki-67 positivity index, which increased steadily in the order benign, premalignant, and malignant. In contrast, it was not possible to relate higher PCNA levels with pre-malignant and malignant oral lesions. We therefore conclude that PCNA immunohistochemistry expression is probably an inappropriate marker to identify oral carcinogenesis, whereas joint quantitative evaluation of p53 and Ki-67, appears to be useful as a tumor marker, providing a prediagnostic estimate of the potential for cell-cycle deregulation of the oral proliferate status

Association of interferon-induced helicase C domain (IFIH1) gene polymorphisms with systemic lupus erythematosus and a relevant updated meta-analysis

9Systemic lupus erythematosus (SLE) is a complex autoimmune disorder presenting heterogeneous clinical manifestations. A number of genes involved in SLE susceptibility are related to the type I interferon (IFN) pathway. IFN mediates innate immune responses and its increased levels contribute to the breakdown of peripheral tolerance. Interferon-induced helicase C domain 1 (IFIH1) activates and modulates IFN responses through its caspase recruitment domain. In this study, we analyzed four IFIH1 single nucleotide polymorphisms (SNPs): rs6432714, rs10930046, rs1990760, and rs3747517, in 337 patients with SLE and 373 healthy individuals from southeast and northeast Brazil. Our results did not find an association between IFIH1 SNPs and SLE (P value >0.025 after Bonferroni's adjustment). However, meta-analysis of peer-reviewed articles from 2008 to 2015 and data from this study indicated an association between rs1990760 and SLE onset (P < 0.05). This is the first association analysis on IFIH1 polymorphisms and SLE susceptibility in Brazilian populations.openopenDe Azevedo Silva, J. ; Lima, S. C.; Addobbati, C.; Moura, R.; Cavalcanti Brandão, L. A.; Trés Pancoto, J. A.; Donadi, E. A.; Crovella, S.; Sandrin-Garcia, P.De Azevedo Silva, J.; Lima, S. C.; Addobbati, C.; Moura, R.; Cavalcanti Brandão, L. A.; Trés Pancoto, J. A.; Donadi, E. A.; Crovella, S.; Sandrin-Garcia, P