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 peripheral 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 collected 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 induction.

Association of HLA-A, -B, -C genes and TNF microsatellite polymorphism with psoriasis vulgaris: a study of genetic risk in Brazilian patients.

This study investigated the genetic association of HLA class I genes and TNF-alpha microsatellites. HLA-A, -B, -C typing was carried out in 92 psoriasis vulgaris patients and 160 healthy individuals using a PCR-SSP method. 70 patients and 71 controls were typed for five microsatellite polymorphisms, TNFa-e. HLA-B*13 Cw*06, HLA-B*57 Cw*06 and HLA-B*39 Cw*12 haplotypes were found to be increased in patients with psoriasis type I when compared to controls, which could determine the susceptibility to development of psoriasis. TNFa4, TNFb1, TNFe1 and TNFa2 b1 c2 d4 e1 haplotypes showed a decreased frequency (p < 0.05) in psoriasis patients when compared to controls. HLA-B*13 allele and HLA-B*13 Cw*06, TNFa11 b4 c1 d3 e3 haplotypes showed increased frequencies (p < 0.05) in patients with type II psoriasis, which suggests susceptibility to the onset of psoriasis. Our results detected polymorphisms of the HLA class I and microsatellite TNF locus which could be markers of genetic predisposition to the disease.

Molecular mechanisms associated with donor-specific microchimerism in peripheral blood of Brazilian patients after liver transplantation.

A large number of studies in liver transplantation have demonstrated allogeneic microchimerism. The clinical and immunologic implications of this finding remain inconclusive, just as the influence of HLA mismatch and donor alloreactivity also are controversial. The present study analyzed the presence of allogeneic microchimerism in liver transplant recipients in relation to donor leukocyte kinetics and rejection episodes. The study was extended to determining the influence of immunogenetic factors in patients after liver transplantation. The presence of allogeneic microchimerism was analyzed on peripheral blood of 50 recipients. DNA extracted from the samples was subjected to typing for HLA-DRB1 and -DQB1 alleles by polymerase chain reactions using sequence-specific primers (PCR/SSP). Microchimerism was identified by nested PCR/SSP. Microchimerism was detected in 72% of patients. There was significant effect of microchimerism on rejection episodes (P=.002), while HLA mismatches did not show significance for one or two mismatches (P=.98). Allogeneic microchimerism detected in the majority of liver transplant patients was observed to be significantly associated with rejection episodes.

Development of donor-specific microchimerism in liver transplant recipient with HLA-DRB1 and -DQB1 mismatch related to rejection episodes.

Migration of donor-derived cells to recipient tissues after liver transplantation has been suggested as a mechanism to induce and maintain allograft tolerance, although important issues remain including acute rejection posttransplantation mortality, and complications related to immunosuppressive therapy. We therefore examined the relation of rejection to chimerism based upon recipient and donor mismatch of HLA-DRB1 and -DQB1 alleles. Laboratory analysis of peripheral blood was performed before and 10 days to 16 months after liver transplantation in 32 recipients, using ganglion or spleen cell samples of respective donors. DNA was extracted for HLA-DRB1 and DQB1 allele typing using polymerase chain reactions with sequence-specific primers (PCR-SSP). Microchimerism was analyzed through nested PCR. Our results confirmed that patients with one or two mismatched HLA-DRB1 and-DQB1 alleles showed microchimerism and no rejection (P <.05). Microchimerism was present in 71.88% of the patients, and a significant association of rejection P <.05 was found when microchimerism was correlated to graft rejection. These results suggest that the presence of microchimerism may be associated with acceptance, tolerance and survival of the allograft.

Undifferentiated spondyloarthropathies: a 2-year follow-up study.

The aim of the study was to analyse the 2-year follow-up of a series of patients with the diagnosis of undifferentiated spondyloarthropathy (uSpA). A prospective study was carried out analysing 68 patients with symptomatic uSpA who fulfilled the European Spondylarthropathy Study Group (ESSG) criteria for seronegative spondyloarthropathies (SpA) and were aged between 18 and 50 years. Inclusion criteria included inflammatory low back pain (ILBP) (without radiographic sacroiliitis), asymmetric oligoarthritis (predominantly affecting large joints in the lower limbs) and heel enthesopathies (Achilles tendinitis and/or plantar fasciitis). Imaging methods included pelvic radiography (at study entry and after 2 years) and calcaneal radiography (at study entry). There was a predominance of male gender (78%), caucasoid race (72%) and positive HLA-B27 (54%), with a mean age of 31 years and mean disease duration of 5 years. The first disease manifestations were ILBP (49%), asymmetric oligoarthritis (35%) and heel enthesopathies (16%). A positive family history of a definite SpA was mentioned by 9% of the patients. Seventeen patients (25%) scored 5 points in the Amor set of SpA criteria; logistic regression analysis showed that HLA-B27, heel enthesopathy and asymmetric oligoarthritis were significantly associated with Amor criteria > or = 6, whereas ILBP was associated with Amor criteria <6. Male sex was associated with heel enthesopathies (p = 0.041) and ankle involvement (p = 0.015). Caucasoid race was associated with ILBP (p=0.015) and buttock pain (p = 0.047). Positive HLA-B27 was associated with wrist involvement (p=0.019) and Amor criteria > or = 6 (p=0.001). After a 2-year follow-up the following outcomes were observed: uSpA 75%; disease remission 13%; ankylosing spondylitis 10%; psoriatic arthritis 2%. Logistic regression analysis showed that buttock pain and positive HLA-B27 (trend) were statistically associated with progression to a definite SpA. In conclusion, uSpA can represent a provisional diagnosis in the group of SpA and a systematic follow-up is necessary in order to better establish the different patterns of the disease.

Primary ankylosing spondylitis: patterns of disease in a Brazilian population of 147 patients.

OBJECTIVE: To analyze patterns of disease in a population of Brazilian patients with primary ankylosing spondylitis (AS). METHODS: Retrospective study (1988-98) analyzing 147 patients with a diagnosis of primary AS according to the modified New York criteria. Selected patients had complete clinical (initial symptom, axial and peripheral involvement, heel enthesitis, extraarticular manifestations) and radiological (sacroiliac, lumbar, thoracic, and cervical spine) investigations, and these data were compared with sex, race, age at onset, and HLA-B27. RESULTS: There was a predominance of men (84.4%), Caucasian race (75.5%), adult onset (> 16 years, 85%), and positive HLA-B27 (78.2%). Family history of AS was noted in 14.3% of the patients. Pure axial AS was observed in 37 patients (25.2%). The predominant initial symptoms were inflammatory low back pain (61.9%) and peripheral arthritis (22.4%). Thoracic and cervical spine involvement was noted in 70.1% of the patients; radiological findings included syndesmophytes in 46.9% and "bamboo spine" in 20.4% of patients. The extraaxial joints most frequently involved were: ankles (39.5%), hips (36.1%), knees (29.3%), shoulders (19%), and sternoclaviculars (14.3%); heel enthesitis was present in 22.4%. Acute anterior uveitis was noted in 14.3% of patients. Male sex was associated with involvement of thoracic spine (p = 0.002), cervical spine (p = 0.002), and hips (p = 0.042), whereas female sex was associated with sternoclavicular (p = 0.024) involvement. Caucasian race presented higher frequency of positive family history (p = 0.023); there was no statistical significance of clinical and radiological variables compared with African-Brazilians. Juvenile onset AS presented higher frequency of ankle (p = 0.012) and knee (p = 0.001) involvement, heel enthesitis (p = 0.001), and total hip replacement (p = 0.038), whereas adult onset was associated with thoracic (p = 0.026) and cervical spine (p = 0.026) involvement and positive family history (p = 0.044). Positive HLA-B27 was associated with ankle involvement (p = 0.007) and heel enthesitis (p = 0.013). CONCLUSION: In this population women showed a milder axial involvement, Caucasian race presented axial and peripheral involvement similar to African-Brazilians, juvenile onset AS was associated with articular involvement of the lower limbs, and positive HLA-B27 was associated with ankle involvement.

Relationship between HLA antigens and infectious agents in contributing towards the development of Graves' disease.

Graves' disease (GD) is an autoimmune thyroid disorder which is associated with the human leucocyte antigens HLA-DR3 and DQA1* O501 in Caucasians. We have explored the possibility that some patients with certain HLA specificities develop anti-HLA antibodies which are correlated with environmental factors that may contribute to the development of GD. We studied 40 GD patients and 157 healthy individuals (controls). Serology was used to type HLA-A, -B, -Cw, and -DR antigens. The frequencies of these antigens in relation to lymphocytotoxic anti-HLA-A-B-Cw-DR antibodies and two environmental factors (Yersinia enterocolitica and Coxsackie B virus) were determined. The frequencies of HLA-B15, -B21 and DR3 antigens were increased, whereas HLA-DR5 antigen was decreased in GD patients. A significant association between HLA-DR3 antigen and lymphocytotoxic antibodies was observed, i.e., IgGs from GD patients were cytotoxic to HLA-DR3+ normal B cells. Following absorption with Yersinia enterocolitica or Coxsackie-B-virus, only Coxsackie-B virus completely inhibited the lymphocytotoxic reactions against HLA-DR3+ B cells. Besides confirming the association of HLA-DR3 with GD, this study also suggests the role of Coxsackie-reactive HLA-DR3 antibodies as contributing factors to the pathogenesis of the disease.

Expression of HLA-DR antigens on T lymphocytes.

Our data have demonstrated, for the first time, expression of HLA-DR antigens on heated T cells (45 degrees C, 1 h) and have confirmed the occurrence of these antigens on mitogen-stimulated T cells. HLA-DR antigens were detected by microlymphocytotoxicity employing defined and non-defined anti-HLA-DR sera. The HLA-DR T cell antigens proved to be the same as the ones expressed on B cells from the same donor. In addition, extra reactions were observed on mitogen-stimulated and on heated T cells which could be abolished by absorption with cytotoxicity negative B cells of the same donor (cytotoxicity-negative-absorption-positive phenomenon).