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Presents a letter to the editor of the December 2001 issue of the 'Transfusion' journal in which a case of panel-reactive antibody was falsely high in the presence of Campath, a chemotherapeutic agent, associated with false-positive HLA antibody screen.

Many diseases, notably those having a strong autoimmune component, have been shown to have an association with specific human leukocyte antigens (HLA). The molecular basis for this genetic association with disease is the fact that HLA bind and present peptides derived from self and foreign protein antigens to the immune system for recognition and activation of the immune response. Previous studies with heterogeneous groups of alopecia areata (AA) patients have suggested associations with some HLA class I and class II antigens. For this study we selected only patients with long-standing disease and stratified them into two groups by strict definitions of duration and extent of disease: those with patchy AA and those with either alopecia totalis (AT) or alopecia universalis (AU). The patients were tissue typed for HLA class II antigens by biomolecular methods that provided antigen discrimination at an allele level. More than 80% of all of the AA patients typed were positive for the antigen DQB1*03 (DQ3), suggesting that this antigen is a marker for general susceptibility to AA. In addition, two other antigens were found significantly increased in frequency only in the group of AT/AU patients, DRB1*0401 (DR4) and DQB1*0301(DQ7). This strongly suggests that the two clinical types of AA, namely patchy AA versus AT/AU, can be distinguished by a genetically based predisposition to extent of disease.

Background: HLA matching is an important component of the United Network for Organ Sharing algorithm for kidney allocation and is the primary factor in the mandatory sharing of kidneys that have zero HLA antigens mismatched with specific patients on the waiting list. An assessment of the HLA-A, -B, and -DR antigen discrepancy rate in the Organ Procurement and Transplantation Network database is desirable to judge the adequacy of the HLA typing data upon which the allocation program is based., Methods: A subset of the Organ Procurement and Transplantation Network database, composed of 10,047 cadaver donor HLA phenotypes that have been repeated by laboratories affiliated with organ recipient centers, was analyzed for the overall rate of HLA phenotype discrepancy and for the type and frequency of discrepancies of the individual HLA antigen assignments. The United Network for Organ Sharing HLA antigen equivalences were applied to the data., Results: Fourteen percent of 12,419 HLA typing comparisons were discrepant in at least one HLA antigen of six possible antigens per phenotype. Of a possible 74,514 individual HLA antigen assignments, 2.7% were discrepant. For African-American donors, the discrepancy rate was 5.1% as compared with 2.4% for Caucasian donors. The most frequent type of discrepancy was the assignment of an antigen blank versus a named antigen., Conclusions: The discrepancy rate is comparatively low and can be expected to improve as more laboratories adopt methods for HLA typing by DNA typing techniques. It is recommended that the HLA data be further reviewed by the laboratories for possible typographical errors and that centers review the UNOS listing of HLA antigen equivalences and encourage laboratories to split HLA antigens.

Alopecia areata (AA) has been shown to be associated with the inheritance of HLA class II alleles. HLA-DQ3 appears to be the general susceptibility allele for AA. Patients with long-standing disease patterns, namely, longterm patchy AA and long-term alopecia totalis and alopecia universalis (AT/AU), can be differentiated by their particular HLA associations. Long-standing AT/AU patients have unique and highly significant associations with HLA antigens DR4, DR11, and DQ7. A complex of early onset, disease severity, family incidence, and associations with HLA DR antigens are characteristic of long-standing AT/AU as distinct from long-standing patchy AA.

The purpose of this study was to identify recipients who are at low or high risk of early cadaveric regraft failure by segregating results of the flow cytometric crossmatch (FCXM) test with previous graft survival time (PGST). Early immunologic kidney regraft failure was analyzed in 103 multicenter recipients by cross-stratifying FCXM negative/positive status with < or =3- and >3-month PGST. T cell and B cell cytotoxicity crossmatches were negative. All were tested retrospectively in the T cell FCXM and 60 of the 103 were also tested in the B cell FCXM. A positive T and B cell FCXM was defined as a mean channel shift of > or = 9 (256 channel log scale) or > or = 40 (1024 channel log scale) for pretransplant crossmatch serum above negative control serum. Recipients received triple immunosuppression therapy and limited-use antilymphocyte induction therapy. Early cadaveric regraft losses were biopsied. Comparably good rates of second kidney graft survival at 3 years were found among three ow risk subsets: 78% for 18 FCXM-positive patients with PGST >3 months, 78% for 49 FCXM-negative patients with PGST >3 months, and 84% for 19 FCXM-negative patients with PGST < or =3 months. in contrast, 53% 3-month and 44% 3-year regraft survival rates occurred in 17 high-risk FCXM-positive recipients with a PGST < or =3 months. The odds ratio for increased relative risk of early second graft loss was 4.5 (confidence interval: 1.32-1.67) for the high-risk versus low-risk subsets (P = 0.009). Within the high-risk subset, 56% (5 of 9) of those who were FCXM T negative B positive experienced early regraft loss. A positive B cell FCXM has an adverse clinical impact only for high-risk regraft recipients. Pretransplant panel reactive antibody levels, pregnancy, number of blood transfusions between grafts, repeat donor HLA mismatches, and regraft recipient HLA mismatches did not correlate with early regraft loss. We conclude that kidney regraft survival rates in low-risk recipients (PGST >3 months/FCXM negative or positive [T and/or B cell] and PGST < or = 3 months/FCXM negative) approach primary graft survival rates and justify retransplantation, but the rate in high-risk regraft candidates (PGST < or =3 months/FCXM positive T and/or B cell) suggests that retransplantation should be performed only with a negative FCXM.

Background: Multiple HLA class I and class II antigen associations have been described for alopecia areata (AA). As in other immune-mediated diseases, the HLA antigens associated with AA could influence the patient's ability to respond to immune challenge from both self- and non-self-antigens and may offer clues to the cause and prognosis of and potential therapy for the disease., Objective: Our purpose was to determine which HLA class II antigens are associated with two forms of long-standing AA, which we define to be long-standing patchy AA and long-standing alopecia totalis (AT) and alopecia universalis (AU). We also examined other factors such as age at onset of disease and familial and patient histories of autoimmune disease for correlation with the two groupings., Methods: Patients were typed for HLA class I and class II antigens by serologic methods and were typed by molecular methods for the subtypes of the HLA class II antigens., Results: HLA-DR11 (DRB1*1104) and HLA-DQ7 (DQB1*0301) were found to be highly significantly increased in frequency in patients with long-standing AT/AU (group III) but not in patients with long-standing patchy AA (group II); both patient groups showed increased frequencies of HLA-DQ3 (DQB1*03). Group III patients were unique in their early age at onset of disease. Familial incidence of AA was 37% in patients who had their first patch by 30 years of age and 7.1% with the first patch after 30 years of age., Conclusion: The data support the differential association of two well-defined clinical forms of AA, namely long-standing AT/AU and long-standing patchy AA, with specific HLA antigens and age at onset; they also suggest that the broad antigen HLA-DQ3, DQB1*03, is a likely candidate for general susceptibility to AA. Our findings also suggest a bimodal pattern of disease with an early-onset form associated with greater severity, long duration, and family history of the disease and a late-onset form characterized by milder severity, shorter duration, and low family incidence.

We evaluated proliferative responses in mixed lymphocyte cultures (MLC) following bone marrow transplantation (BMT) in 14 recipients of T cell-depleted haplo-compatible parental marrow: 11 for the treatment of severe combined immunodeficiency (SCID), 2 for leukemia and 1 for Wiskott-Aldrich syndrome (WAS). We compared the results obtained in 9 SCID patients and 1 WAS patient with split chimerism (T cells of donor origin, B cells and monocytes of recipient origin) to 4 patients (2 SCID and 2 leukemias) who were full chimeras (T, B and monocytes of donor origin). In the full chimeras, as with the fresh donor PBMC, fresh donor T cells did not proliferate in the MLC to recipient non-T cells (E-). In this group there were no differences (p > 0.2) between the responses of engrafted T and fresh donor T to recipient E- cells. We found tolerance of engrafted donor T cells to residual mismatched T cell-depleted (E-) recipient cells in the split chimera group. In this group the engrafted T cells had low or no responses in MLC to HLA mismatched E- host cells compared with fresh donor cells (p < 0.001). In 3 of 8 split chimera patients that we tested the addition of small numbers (5000-10,000) of freshly isolated donor T cells, irradiated or not, resulted in a two fold increase in the engrafted T cell response to recipient E- cells. In contrast, in 3 of 3 full chimeras tested, the addition of fresh donor T cells had no demonstrable effect on the response of engrafted T cells to recipient E-.(ABSTRACT TRUNCATED AT 250 WORDS)

Twenty-three patients from the United States with anti-glomerular basement membrane nephritis (Goodpasture's syndrome) were HLA class I and class II typed by serology and HLA-DR and HLA-DQB typed using sequence-specific oligonucleotide (SSO) probes. Protocols used were those of the 11th International HLA Workshop. We were able to confirm the strong association of DR2 with the disease and, using the molecular techniques, showed that all DR2 patients were restricted to DRB1-1501 and DQB1-0602 alleles. We also found highly significant associations between disease and the alleles of DRB1-0301 and DQB1-0201. DR4 alleles as a group were not significantly more frequent among patients, but the allele DRB1-0404 did appear to be associated with the disease. The use of SSO typing provides an expanded opportunity for refined analysis of HLA and disease associated alleles.

We describe our 9-year experience with lectin-treated T-cell-depleted haplocompatible parental bone marrow transplantation (BMT) for 24 patients with severe combined immunodeficiency disease (SCID). Nineteen of 21 evaluable patients had T-cell engraftment; 2 of 11 patients tested had B-cell and monocyte engraftment. Fourteen of 24 (58%) patients are alive 7 months to 9.8 years post-BMT. Seventeen of 24 patients received pretransplant conditioning with chemotherapy and/or total body irradiation, and 8 of 24 received more than one transplant. Patients who received conditioning had a survival rate of 61% versus 57% for those who received no conditioning. None received graft-versus-host disease (GVHD) prophylaxis and no patient had acute or chronic GVHD greater than grade I. Kinetics and follow-up of immune recovery were analyzed in 14 patients who are greater than 1 year from transplant. Half of the patients showed evidence of T-cell function by 3 months and normal T-cell function by 4 to 7 months post-BMT. On average, T-cell numbers and subsets became normal 10 to 12 months posttransplant. Recovery of B-cell function was more delayed, although in most patients B-cell numbers and IgM levels were normal by 12 months post-BMT. B-cell function, as determined by isohemagglutinin titers or specific antibodies to pneumococcal polysaccharide, keyhole limpet hemocyanin, or tetanus toxoid, became normal in 10 of 14 patients 2 to 8 years post-BMT. Seven of the 14 are off gammaglobulin therapy. Production of isohemagglutinins tended to predict recovery of antibody response to pneumococcal polysaccharide (P < .064). Based on these results, we believe that haplocompatible BMT is an effective, curative treatment for patients with SCID who lack an HLA-matched related donor.

To test the hypothesis that non-inherited maternal antigens (NIMAs), which reportedly afford protection against sensitisation by random transfusions, can provide protection against repetitive antigenic exposure of donor-specific transfusion (DST), 140 DST patients whose donors were mismatched for NIMAs and 71 whose donors were mismatched for non-inherited paternal antigens (NIPAs) were studied. The rate of sensitisation in the two groups of patients was similar (22.1% vs 15.5%). There was no difference in sensitisation to NIMAs and NIPAs between patients who received azathioprine and those who did not. The formation of donor specific HLA antibody was comparable in the two groups. After kidney transplantation there were no differences in 1-year graft survival or the incidence of rejection episodes. These findings suggest that NIMAs do not provide lifelong protection against subsequent repetitive antigen challenge and sensitisation.

To test the hypothesis whether "anti-idiotypic" antibodies (Ab2) were involved in the loss of sensitization following donor-specific blood transfusions (DST), we investigated nine potential kidney graft recipients who became transiently sensitized after DST. Inhibiting "anti-idiotypic" activity of post-DST sera was determined using a complement-dependent cytotoxicity inhibition assay. The follow-up after DST ranged from 9 to 66 months. The nine patients developed 12 different anti-HLA antibodies (Ab1). Inhibiting post-DST serum activity was found in relation to four of them, while enhancement of cell killing caused by post-DST sera was observed in relation to six anti-HLA antibodies. In two patients presenting with more than one anti-HLA antibody inhibition was found with only one of the antibodies, indicating that the blocking of Ab1 was specific for the respective antibody. Enhancement was associated with a significantly prolonged sensitization of the patients. On the average, 5.7 +/- 5.0 months were necessary before "anti-idiotypic" activity was developed after the loss of sensitization, whereas enhancement was found immediately thereafter. Testing by flow cytometry indicated that enhancing sera still contained subthreshold levels of Ab1. Our results indicate that DST can induce the development of "anti-idiotypic" antibodies following a short period of sensitization. This finding provides further evidence that anti-idiotypic antibodies might be relevant factors in the eventual disappearance of sensitization to HLA antigens.

Characteristics of the sensitization response to donor-specific transfusion (DST) have been studied in the context of the pretransfusion panel reactive antibody (PRA) status of the recipient. Two distinct patterns of response to DST and Imuran treatment have been found. In patients with one-haplotype-matched donors, the panel nonreactive patient (PRA less than 10%) has a 19% incidence of DST sensitization that is further reduced by Imuran treatment to 6%; antibodies are both anti-T cell and anti-B cells, are transient, and are specific to the mismatched HLA antigens of the blood donor. Panel-reactive patients (PRA greater than 10%) have a 56% incidence of DST sensitization; the antibodies appear within 2 weeks of the first transfusion, are anti-T cell, and are generally of broad specificity and persistent duration consistent with amplification of a previous antigenic exposure; Imuran seems to have little or no effect in reducing the incidence of sensitization in these panel-reactive patients. However, panel reactive patients whose PRA levels spontaneously fall to panel-nonreactive levels immediately prior to DST therapy have an exceedingly low (0-8%) incidence of sensitization with or without Imuran coverage.

Using linear logistic regression, six factors were identified as important predictors of risk of DST sensitization in a group of 195 patients. Factors increasing the risk were: percent panel reactive antibody (PRA), previous transplants, and pregnancy; those decreasing the risk were HLA antigens matched, third-party blood transfusions, and Imuran administration. From this analysis, the magnitude of the effect of each factor on the risk of sensitization was obtained. An equation was then obtained that can be used to compute an estimated probability of sensitization (PS) for each patient. As a test of predictive ability of the model, the PS was calculated for 66 patients in an independent patient group. These observations were arranged according to the estimated probability and then divided into intervals of risk. Overall, for each interval, a very high level of agreement was found between the predicted and actual number of sensitized patients. A total of 16.13 patients were predicted to become sensitized and 17 actually did.