Factors which have a significant effect on the survival of human skin grafts.

Survival of 436 ABO-compatible skin grafts exchanged in 97 Caucasian families was prolonged if donor and recipient were genotypically, as compared with phenotypically, HLA identical. Among skin grafts between haploidentical family members, a mismatch at the A locus was equivalent to a mismatch at the B locus. Skin grafted from child to mother survived longer than did skin grafted between other family members, other variables being equivalent. A highly significant positive correlation was found between the age of recipient and skin graft survival. In addition, a significant interaction was found between the relationship of donor and recipient and degree of antigen match.

The antiglobulin microcytotoxicity assay in HL-A genotyped families.

HL-A genotyping was accomplished in 30 families (8 black, 21 white, and 1 American Indian) based on serological results obtained by our ususal lymphocytotoxicity assays. Each family was further tested by an antiglobulin microcytotoxicity method. Segregation patterns obtained by the latter method, compared with those of the former, showed few discrepancies. HL-A-identical siblings were serologically similar by the antiglobulin assay with frequency of discordant reactions at the same level as that of our regular two-stage lymphocytotoxicity assay. The antiglobulin method was shown to be highly reproducible with 1.3% discordance between duplicate tests. Many sera employed in routine cytotoxicity testing gave positive reactions with all family members in the antiglobulin assay (39% all positive by antiglobulin versus 16% by the regular cytotoxicity test), so that this method has limited usefulness for routine HL-A typing. The antiglobulin assay may have particular value, however, for identifying HL-A haplotypes in families, especially non-Caucasian, which give infrequent positive reactions in the usual lymphocytotoxicity assays.

The effect of parental HLA compatibility on the expression of paternal haplotypes in offspring.

The compatibility of HLA-A,-B expression between mother and offspring was examined in 410 families serologically tissue typed within a single transplant lab from 1972 thru 1982. The study group included 410 mothers of 1719 children (range 2-13/mother), with 352 one-father and 58 multiple-father families There were seven cases of monozygous twins and seven cases each of maternal and paternal allelic recombination. The degree of haplotype matching between the oldest offspring and subsequent siblings was within the expected range of distribution. The number of maternal HLA-A,-B antigens matched or mismatched with paternal antigens of the offspring did not show a significant difference between early born or late born siblings either in one-father or multiple-father families. In addition, where the mother showed significant sensitization to paternal HLA-A,-B antigens ther was no apparent selection against the incompatible paternal HLA antigens or associated haplotypes in subsequent offspring. These data suggest that maternal HLA compatibility with the father is not a significant selective factor in determining the expression of paternal haplotypes in offspring.

Segregation of three recently identified HLA specificities in an American Black family.

Three recently identified HLA specificities have been detected in a ten-member American Black family using 8th International Histocompatibility Testing Workshop and local antisera. Independent segregation of the two principal components of 8w59 (Bu and SV) was demonstrated. An Aw19-related specificity also segregated in the family.

Lymphocytotoxicity crossmatch proficiency testing among regional transplant centers.

During an eight and a half-year period (1976-1984), 408 combinations of different cells and sera involving 12,652 lymphocytotoxicity crossmatch reactions performed by 21-37 histocompatibility laboratories were studied in 20 proficiency tests conducted by the South-Eastern Organ Procurement Foundation. Consensus by 75% or more laboratories were obtained on 336 (82.4%) of these test samples: of the 10,410 reactions examined with the use of these consensus cells and sera, only 649 (6.2%) were discordant. Considering positive and negative reactions separately, the discordant (false) positive and negative rates were similar (6.1%, 6.4%, respectively). Varying specific factors in given tests indicated that discordant results were significantly reduced by (1) dispensing sera in trays centrally rather than locally; (2) using a standard one-wash procedure rather than local or three-wash methods; and (3) using reagent (monospecific) rather than patient (polyspecific) sera. Use of standard versus local rabbit complement did not significantly influence the concordance of results.

Familial predisposition to filarial infection--not linked to HLA-A or-B locus specificities.

Two hundred and twenty-five Polynesians were selected from a larger study population for the evaluation of potential genetic influences on the susceptibility to bancroftian filariasis. Analysis showed that there was significantly familial clustering of patients with filariasis and that this clustering was most compatible with genetic transmission of disease susceptibility. The data best fit a model in which the hypothetical gene for filariasis was recessive with a frequency of 0.82 +/- 0.15 in the population and a penetrance of 0.62 +/- 0.14. The alternative hypothesis that susceptibility was environmentally (i.e., not genetically) determined was also compatible with the data but was estimated to be 1.9 times less likely to account for the observed findings than the genetic hypothesis. Extensive evaluation of HLA-A and -B locus specificities failed to detect significant linkage either between particular antigen specificities and the clinical manifestations of filariasis or between individual haplotypes (indicated by HLA markers in studies of large families) and the predisposition to filarial infection or disease.

Immunobiology of primary intracranial tumors. Part 8: Serological responses to active immunization of patients with anaplastic gliomas.

Serial serological studies were carried out on 19 of 20 patients with malignant gliomas who were actively immunized with one of two human glioma tissue culture cell lines (D-54MG or U-251MG). Most patients mounted a significant serum reaction to histocompatibility antigens (HLA's), as well as an antibody response to fetal bovine serum (FBS) which was added to the glioma-cell inoculum. These two sources of antibody accounted for greater than 90% of the antibody induced by these inoculations. Two patients continued to have significant amounts of binding antibody to the original immunizing cell line following exhaustive absorptions of FBS and these two had all remaining significant antibody removed by further absorption of the serum against the 2-T osteogenic sarcoma tissue culture cell line known to possess antigens cross-reactive with human gliomas. One single patient continued to show significant antibody binding to the original glioma cell line following absorption against FBS, human platelets, and the 2-T cell line, and therefore seems to have produced glioma-distinctive antibodies in response to immunization. The antibody preparation from this patient was also cytotoxic against the original glioma cell line, as well as another recently cultured human glioblastoma cell line. The significance of these serological studies is discussed as it relates to immunological responses patients with gliomas may make to active immunization.

Problems arising from the use of the HLA system in paternity testing.

Characterization of the HLA antigens present on lymphocytes has become an important procedure in paternity testing. This paper presents data on two cases in which the HLA antigens exhibited by the mother, child and alleged father were consistent with paternity but where the other genetic markers clearly showed exclusion of paternity. The use of HLA data alone to calculate probability of paternity in these two cases produced misleading figures. Caution must be exercised in using HLA results to calculate the probability of paternity, especially when there is reason to believe that the alleged and natural fathers are relatives.

Immunogenetic factors that may contribute to ethnic differences in renal allograft survival.

In the United States, allocation of cadaveric kidneys is federally regulated and based on the concept of equal access to all patients, regardless of race, sex, age, or socioeconomic status. Nevertheless, it has been widely reported that African American patients with renal disease wait longer for kidney transplantation and, once transplanted, have poorer graft survival. We have assessed immunogenetic factors that may contribute to ethnic differences in allograft survival by examining the distributions of ABO blood groups, HLA antigens and haplotypes, percent reactive antibody (PRA), age, and gender in our local patient population. Approximately 62% of patients at our transplant center waiting for renal transplantation are African American; 39% are female. Age distribution is comparable to that reported nationally. ABO blood groups of patients on the waiting list are distributed similarly to those reported nationally for other renal patients. Sensitization to HLA antigens, through either blood transfusion, prior transplant, or pregnancy, has been strongly associated with poorer graft survival. Although, as expected, distribution of PRA was significantly different for males versus females at one time point, it did not differ between ethnic groups in our patient population. HLA polymorphism was assessed by comparisons of HLA allele and haplotype frequencies determined by analyses of African American and Caucasian families typed in our program since 1991. Haplotypes observed in each ethnic population were subjected to a variety of statistical analyses. Coefficient of contingency and Cramer's V statistic (measures of degree of association) were consistently higher for Caucasian haplotypes than for those of African Americans. Significantly more unique HLA haplotypes were observed among African American families than among Caucasian families. Thus, our data provide evidence for greater HLA linkage disequilibrium in Caucasians than in African Americans. HLA antigen and haplotype polymorphisms are likely, therefore, to be major immunogenetic factors contributing to ethnic differences in renal allograft survival.

Regional organ procurement (ROP) trays in renal allograft distribution and outcome.

ROP trays containing patient serum samples and distributed by the South-Eastern Organ Procurement Foundation (SEOPF) were instituted to increase the likelihood of transplanting potential renal recipients who are highly sensitized to HLA antigens. This study examines kidney distribution and transplant outcome to assess equitable placement and clinical function post transplant with and without the use of ROP trays. Data were collected over a 26-month period on the distribution of kidneys from 328 consecutive SEOPF donors from whom at least 1 kidney was procured. Shared kidneys were placed via the UNOS and SEOPF-variance computer match programs. Of 656 kidneys, 596 were placed into 582 recipients; 60 were not used. ROP trays were used in placement of 492 kidneys and were not used for placement of 104 kidneys. Outcome was determined for 435 kidneys transplanted into SEOPF recipients. Only 33 (6.9%) recipients with ROP tray use and 10 (9.8%) without were sensitized to HLA. A 10% increase in placement to the originally intended recipient was seen with ROP tray usage over kidneys placed without ROP tray use (p < or = 0.025). Recipients matched using ROP tray data averaged 29 positions higher on the match printout. There was no difference in tray use regarding placement of kidneys within or outside the donor's local UNOS region, nor was there a difference in mean HLA match of transplant pairs with and without ROP tray use, 3.2 and 3.1 antigens, respectively. Cold ischemia time was similar, 22.9 and 23.6 h, respectively, for kidneys placed with and without ROP trays. At post-transplant discharge, there were no differences in patient status, graft failure, rejection treatment, dialysis need, or urine output whether or not ROP trays were used. Significantly, however, plasma creatinine at discharge and at 12 months was lower for those placed with ROP trays (2.5 mg/dl and 1.7 mg/dl) vs (3.1 mg/dl and 1.9 mg/dl), respectively. During this time period, all kidneys transplanted with use of ROP trays functioned as well or better than those transplanted without ROP tray placement. Thus, the use of ROP trays appeared to have a beneficial effect in getting more recipients of higher priority transplanted with equivalent, if not better, graft function.

Repeated HLA mismatches and second renal graft survival in centers of the South-Eastern Organ Procurement Foundation.

To determine if repeated HLA mismatches and other putative risk factors were predictive of second graft failure in second grafts performed at Southeastern Organ Procurement Foundation (SEOPF) members centers, we identified a cohort of 753 retransplants in which one or more HLA antigens were mismatched in primary grafts. Of this group, 158 (21.1%) received second grafts with repeated mismatches of one or more HLA-A, B, or DR antigens that were previously mismatched in the primary graft (RMMs). All regrafts were cadaveric kidneys transplanted between 1982 and 1995. Multivariate analysis of 19 covariates in 438 regrafts identified four independent factors that were predictive of graft survival frequency in second transplants. Three of the four factors were associated with a reduced risk for graft loss in retransplants: cyclosporin A (CsA) use in graft (p = 0.0001, RR = 0.26), peak PRA < 50% (p = 0.008, RR = 0.52) and white donor race (p = 0.035, RR = 0.63). One factor was associated with an increased risk of second graft failure, namely, blood transfusion prior to the first graft (p = 0.026, RR = 5.14). None of the other 15 factors exerted significant additional risk to regraft survival frequency in these SEOPF data. In multivariate analysis, RMMs were not associated with altered graft survival frequency in regrafts (p = 0.944, RR = 0.99). We than used univariate analyses to determine whether RMMs had adverse effects on GS in particular subsets of recipients that were thought to be at increased risk for the second transplant failure. Univariate analyses were performed with methods that are sensitive to early events (Wilcoxon) and late events (log-rank). The variables tested were CsA use for the regraft, duration of primary graft function, panel reactive antibody levels (PRA), immunopathologic cause of first graft failure, and HLA mismatch of the second graft. These analyses indicated that repeated HLA mismatches were not an associated risk factor in any of these subgroups. These SEOPF data indicate that RMMs are not predictive of increased frequency of graft loss in cadaveric donor second transplants. We conclude that our results do not support a policy of routine avoidance of RMMs, which may result in increased waiting time for a second donor without providing an improved graft survival rate. The available literature suggests that HLA antibody identification, the use of sensitive flow cytometric and antiglobulin-augmented cross-match tests, together with appropriate donor selection, optimal immunosuppression and patient management may be sufficient to avoid the early loss of second grafts.

Reduced graft rejection with good HLA-A and B matching in high-risk corneal transplantation.

We examined the effect of matching for HLA-A and B antigens on the success of corneal transplantation in a single-center, prospective, masked study that began in March 1979. The study involved 97 consecutive recipients at high risk because of prior corneal graft rejection or serious vascularization of the native cornea. Donor corneas were selected on the basis of ABO-blood-group compatibility, a negative lymphocyte crossmatch, and optimal HLA-A and B matching; all clinical personnel were "masked" to the degree of HLA matching during the study. Among 38 patients receiving corneas with a good HLA match (two or more antigens), only 8 (21 percent) had graft rejection, as compared with 29 of 59 (49 percent) with a poor match (no or one antigen) (P less than 0.010). The mean (+/- SE) difference in rejection-free graft survival increased with time: 88.4 +/- 5.5 percent versus 73.5 +/- 5.9 percent at six months, and 80.1 +/- 7.5 percent versus 38.5 +/- 7.9 percent at two years. Cox multiple regression analysis, which included the HLA-A and B match and nine other potential confounding variables and risk factors also identified a significant (P less than 0.009) relative risk (4.6) of rejection reactions as well as irreversible graft rejection (P less than 0.016; relative risk, 11.2) with poor HLA-A and B matching. Our findings indicate that good HLA-A and B matching yields a significant long-term benefit in reducing the number of episodes of graft rejection and subsequent failure in high-risk recipients of corneal transplants.

A randomized study comparing leukocyte-depleted versus packed red cell transfusions in prospective cadaver renal allograft recipients.

A prospective randomized study at a single renal transplant center between 1980 and 1982 compared the influence of leukocyte-depleted versus packed red cell pretransplantation blood transfusions on patient sensitization to leukocyte (HLA) antigens, likelihood of receiving a graft, and eventual transplantation results. All consenting potential cadaver renal transplant recipients (n = 107) were randomly assigned to receive transfusions at 6-week intervals with either packed red cells (Group 1) or leukocyte-poor red cells (Group 2) until they were transplanted. Actuarial graft and patient survival were identical for graft recipients in both groups. Although the likelihood of receiving a graft was associated with the level of pretransplant sensitization to leukocyte (HLA) antigens (p less than 0.02) as measured by the percent of panel reactive antibody (PRA), it was not associated with the type of blood used. The highest mean peak reactive PRA level for all patients showed a low but significant increase (29 +/- 4 versus 43 +/- 5%; p less than 0.0005) following entry into the transfusion protocol, but the rate of increase was the same for patients in both treatment groups. The likelihood of receiving a transplant was primarily associated with a history of prior graft rejection (p less than 0.05), and patients with prior graft loss had the greatest increase in sensitization following entry into the transfusion protocol. These findings indicate that using leukocyte-poor red cells for pretransplant transfusions provided no added benefit when compared with packed red cells in terms of patient sensitization, the likelihood of receiving a transplant, or eventual graft survival.

HLA histocompatibility antigens in a Polynesian population -- Cook islanders of Mauke.

Polynesians living on the island of Mauke in the Cook Island group were typed for HLA-A and -B locus antigens. The Mauke population has restricted HLA polymorphism, with five A-locus antigens and four B-locus antigens accounting for a majority of the HLA phenotypes. Although some differences in antigen frequency were found when Mauke Islanders were compared with Polynesians from Easter Island and Samoa, the Mauke Islanders were closer in their HLA antigenic profile to polynesians than to Melanesians.

Histocompatibility testing for keratoplasty in high-risk patients.

Forty-eight consecutive patients at high risk for corneal graft rejection were transplanted with corneas from donors selected on the basis of a negative lymphocyte crossmatch, ABO blood group compatibility, and maximized HLA-A, -B matching. Graft survival in this study group was compared to a retrospective control group of 72 consecutive high-risk transplants performed in patients receiving randomly obtained corneal donors. Demographic parameters, cause of primary disease, and incidence of prior graft rejection were no different between the two groups. Graft survival at one year, calculated by the Kaplan-Meier method, was 78% for the negative crossmatch study group vs 52% in the uncrossmatched control group (P less than 0.05%). All graft failures in the negative crossmatch group were in poorly HLA matched recipients. While patients with evidence of nondonor specific humoral presensitization to HLA antigens experienced earlier graft rejection, overall graft survival was not associated with such nonspecific presensitization. These findings indicate that prospective histocompatibility testing can improve corneal allograft survival for high-risk patients by better identification of appropriate donors.