HLA phenotypes of ESRD patients are risk factors in the panel-reactive antibody (PRA) response.

To determine whether recipient HLA phenotypes are correlated with an increased or decreased risk of alloantibody sensitization in end-stage renal disease (ESRD) candidates for first or repeat kidney transplantation; we analyzed 19440 kidney allograft recipients consisting of 13,216 Caucasians and 6224 non-Caucasians transplanted between 10/87 and 11/98 at South-Eastern Organ Procurement Foundation (SEOPF) member institutions. Relative risk values and 95% confidence limits were obtained using Wolfe's method. Logistic regression was used to adjust for covariates that influence sensitization, i.e. ethnicity, gender, age, pregnancies, transfusions, primary/repeat transplant and living versus cadaver donor. Univariate analysis of the entire cohort indicated that nine HLA allelotypes (DR1,4,7; B8,12,40; A1,2,11) were associated with a significantly reduced risk of sensitization, and five allelotypes (B42,B53; A 10,19,36) were associated with an increased risk of PRA responses. Corrected for the number of statistical comparisons, recipients with DR1, DR4, A1 or A2 were 15% less likely to be sensitized per allelotype. Recipients with B42, B53 or A36 were at increased risk of preformed antibodies, after correction of the P value, for an average of 38% increased risk per allelotype. In the multivariate analysis, HLA phenotypes identified as independent risk factors associated with protection against sensitization were DR1,4,7; B12(44,45); and A1,2, with an average reduced risk of 9% per allelotype. The only independent susceptibility allelotype was A36 with an increased risk of 29%. The A10 (25,26,34,66) group reached borderline significance. We also looked for HLA-DR,-B,-A combinations that could potentially represent protective or at risk haplotypes/genotypes. Stepwise logistic regression identified five combinations associated with protection: DR1-B35-A3; DR1-B35-A2; DR1-B44-A2; DR4-B44-A2; DR7-B57-A1 (RR range 0.83-0.63) with 27% average reduced risk per combination. Phenotype combinations associated with an increased risk of sensitization were: DR2-B44-A2; DR2B53-A2; DR3-B8-A1: DR3-B42-A30; DR6-B42-A30; DR11-B53-A30 (RR range 2.76-1.48) with an average increased risk of 70% per combination. This study provides strong evidence that HLA-linked genes influence the anti-HLA PRA response. The magnitude of the altered PRA response risk in DR-B-A combinations was approximately twice that of the allelotypes at individual loci. HLA-DR genes seemed to contribute most of the altered risk. The correlations between DR types and PRA responsiveness are consistent with the DR types previously regarded as predictors of kidney graft survival. The magnitude of increased PRA risk attributable to an allelotype or combination was approximately twice that associated with a decreased risk. We conclude that some HLA class II-linked genes modulate the PRA response in a clinically significant manner. This immune response gene (Ir) regulation probably operates through polymorphic HLA molecules in their physiologic roles of antigen processing and presentation to helper T cells.

HLA-DQ matching in cadaveric renal transplantation.

The impact of matching for the human leukocyte antigen (HLA)-DQ phenotype in cadaveric renal transplantation is unclear. We analyzed the effect of matching serologically defined HLA-DQ phenotypes on renal allograft survival in 12,050 first cadaveric renal transplants (recipients were 63.5% white and 36.5% African-American). Recipients were entered into the South-Eastern Organ Procurement Foundation (SEOPF) database between 1 October 1987 and 6 June 1995. A series of life table analyses were done to test the equality of survival curves for HLA-DQ match, both alone and accommodating for differences in recipient race and HLA-DR match. Cox regression models were then performed to detect differences in allograft survival based upon HLA-DQ match. Initial adjustments were done by recipient race. Subsequent adjustments were done by recipient and donor race, age and sex, cold ischemia time (CIT), body mass index (BMI), cyclosporine A (CyA) use, peak panel reactive antibody (PRA) titer, year of transplant, presence of diabetes mellitus (DM), and degree of HLA-A,B and HLA-DR match as covariates. The effect of varying degrees of HLA-DQ match on graft survival were similar between the two races (p = 0.87). In all recipients, an 8.3% reduction in graft failure was observed for each increase in HLA-DQ match using the Cox regression model adjusted only for recipient race (p = 0.004). A non-significant 3.0% reduction in graft failure (p = 0.38) was observed for each level of increasing HLA-DQ match when using the Cox regression model adjusted for recipient and donor race, age and sex, CIT, BMI, CyA use, year of transplant, DM, HLA-A,B and -DR match. In this model, superior HLA-A,B match and HLA-DR match, recipient and donor age, male donor sex, shorter CIT, white race of recipient, lower peak PRA, CyA use, and absence of DM significantly improved graft survival (all < or = 0.004). We conclude that HLA-DQ matching does not significantly affect cadaveric renal allograft survival once adjusted for other known predictors of graft outcome.

Chronic social stress, social status, and susceptibility to upper respiratory infections in nonhuman primates.

OBJECTIVE: The objective of the study was to assess the roles of social stress and social status in susceptibility to upper respiratory infection. METHOD: Sixty male cynomolgus monkeys were randomly assigned to stable or unstable social conditions for 15 months. Two markers of social status, social rank and percent of behaviors that were submissive, were assessed at independent observation periods. Endocrine, immune, and behavioral responses were each assessed (at 3-month intervals) during the 9th through 14th months of the study. At the beginning of the 15th month, all animals were exposed to a virus (adenovirus) that causes a common-cold-like illness. The primary outcome was whether or not an animal developed an infection (shed virus) after viral exposure. RESULTS: Although the social instability manipulation was associated with increased agonistic behavior as indicated by minor injuries and elevated norepinephrine responses to social reorganizations, the manipulation did not influence the probability of being infected by the virus. However, low social status (as assessed by either marker) was associated with a substantially greater probability of being infected. It was also associated with less body weight, greater elevated cortisol responses to social reorganizations, and less aggressive behavior. However, none of these characteristics could account for the relation between social status and infection. CONCLUSIONS: Social stress was not associated with susceptibility to infection. However, animals with lower social status were at higher risk than high social status animals.

MHC-DRB allelic sequences incorporate distinct intragenic trans-specific segments.

The second exon of primate MHC-DRB genes encodes discrete areas of allelic hypervariability (HVR), which are used as the basis for lineage assignments to determine genetic and evolutionary relationships. Comparisons of these regions have led to the "trans-species hypothesis", which proposes that certain MHC alleles from one species are more closely related to those from other species than they are to each other; i.e., that allelic lineages are ancestral in origin. We evaluated this paradigm in an analysis of macaque and baboon MHC-DRB genes using oligotyping and sequencing of 87 new nonhuman primate DRB alleles. A remarkable conservation of sequence motifs in the HVRIII region (codon 60-79) was observed, detected both by hybridization and by sequencing; some of these motifs were found in species such as prosimians that have diverged from the human lineage 50 MYA. However, these fixed HVRIII motif sequences nevertheless occur on a background of diverse lineages suggesting that it is the segmental motif, rather than the allele per se which is trans-specific in origin. Sequences within the first hypervariable region (codons 7-14) identified lineage assignments to several DRB loci (DRB1, DRB3, DRB4, DRB5, DRB6 and DRB7), although a large number of DRB nucleotide sequences did not correspond to a defined allelic motif, suggesting that many of the nonhuman sequences lack human HVRI homologs and have accumulated additional intraspecies variation subsequent to speciation. While there are certain allelic lineages in HVRI that show trans-species conservation, other sequence motifs seem purely species-specific. These differences suggest that HVRI and HVRIII regions have distinct mechanisms for maintenance of trans-specific sequence elements, with different evolutionary histories for segmental nucleotide conservation.

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.

HLA associations in end-stage renal disease due to membranous glomerulonephritis: HLA-DR3 associations with progressive renal injury. Southeastern Organ Procurement Foundation.

Membranous glomerulonephritis (MGN) is the most common cause of idiopathic glomerulonephritis in American adults. African-Americans develop end-stage renal disease (ESRD) due to chronic glomerulonephritis four times more often than whites. To determine whether HLA phenotype associations existed in the subset of MGN patients with ESRD we analyzed HLA frequencies, by race, in patients with MGN entered in the Southeastern Organ Procurement Foundation registry between 1982 and 1992. HLA frequencies from 250 renal transplant patients with MGN (190 whites and 60 African-Americans) were compared with 4,506 race-matched cadaveric kidney donor controls (4,039 whites and 467 African-Americans). Race-specific odds ratios (ORs) were calculated and fitted into a log-linear model to determine associations between MGN and HLA frequencies. The reported values were considered significant (P < 0.05) after Bonferroni correction for multiple comparisons. HLA-DR3 and HLA-DR5 frequencies were increased in cases of both races compared with race-matched controls (race-combined ORs, 2.22 and 1.61, respectively; all P < 0.02). Interracial analyses revealed that HLA-DR7 frequency was decreased solely in whites with MGN (OR, 0.53; P < 0.04). The results of this study indicate that HLA-DR3 and HLA-DR5 are positively associated with ESRD due to MGN in patients of both races and that HLA-DR7 is negatively associated with MGN in whites. These analyses confirm the published reports of HLA-DR3 association with MGN in Chinese, French, British, Chilean, and American white populations. The novel association of HLA-DR5 may reflect the fact that the MGN cases in this study all had ESRD.(ABSTRACT TRUNCATED AT 250 WORDS)

HLA associations in IgA nephropathy and focal and segmental glomerulosclerosis.

Twenty percent of patients initiating Medicare-supported end-stage renal disease (ESRD) therapy in the United States have chronic glomerulonephritis-induced ESRD. IgA nephropathy (IgAN) and focal and segmental glomerulosclerosis (FSGS) likely account for many of these incident dialysis cases, although patients presenting with advanced renal insufficiency may not receive renal biopsies. To determine whether HLA phenotype associations existed in the subset of IgAN and FSGS patients who develop ESRD, we analyzed HLA frequencies by race in patients with these etiologies of ESRD entered in the South Eastern Organ Procurement Foundation (SEOPF) database. Serologically determined HLA frequencies from 605 renal transplant recipients with ESRD due to FSGS and 196 renal transplant recipients with ESRD due to IgAN were compared with those of 4,506 race-matched cadaveric kidney-donor controls. Race-specific odds ratios (ORs) were calculated and fitted into a log-linear model to determine associations between the HLA system and ESRD due to IgAN and FSGS. Values reported were considered significant (P < 0.05) after Bonferroni correction for multiple comparisons. HLA-B27 and HLA-DR1 frequencies were increased and HLA-DR2 frequency was decreased in African-American and white IgAN-induced ESRD cases compared with race-matched controls (race-combined OR of 2.10, 1.89, and 0.57, respectively; all P < or = 0.004). HLA frequency differences were not observed in FSGS-induced ESRD patients compared with controls. The results of this study indicate that HLA-B27 and HLA-DR1 are positively associated and HLA-DR2 is negatively associated with IgAN-induced ESRD in patients of both races.(ABSTRACT TRUNCATED AT 250 WORDS)

Risk of liver disease in HCV-seropositive kidney transplant recipients.

OBJECTIVE: This study determined whether renal allograft recipients with antibodies to hepatitis C virus (HCV) at the time of transplantation experienced increased morbidity or mortality from hepatitis, liver disease, or hepatocellular carcinoma compared with patients without anti-HCV. SUMMARY BACKGROUND DATA: Chronic liver disease is a cause of significant morbidity and mortality after kidney transplantation and the contribution of HCV to this problem has not been determined. The recent characterization of the HCV genome has resulted in the development of screening tests for antibody to HCV, allowing the identification of end-stage renal disease patients with anti-HCV who are candidates for transplantation. The risk to these patients for the development of hepatic complications after subsequent transplantation is unknown. METHODS: Archived sera obtained from 163 kidney transplant recipients at the time of transplantation were tested for anti-HCV using the Abbott HCV 2.0 second-generation test system. Sera containing anti-HCV were further analyzed for reactivity against specific HCV recombinant proteins, including core, NS3 (c33c), and NS4 (c100-3), to determine whether a pattern could be identified in patients with hepatic complications. The follow-up of all patients was current (mean length of follow-up was 33 months) to identify patients with hepatic complications. All patients had previously been tested for HBSAg. RESULTS: Twenty-nine patients (18%) had anti-HCV and three (1.8%) had HBSAg. Forty-five patients (28% of total) had transient elevations of AST or ALT without subsequent evidence of liver disease. Three patients had a syndrome of acute hepatitis. Chronic liver disease developed in only six patients (3.6%) after transplantation. Four had anti-HCV only, one had HBSAg only, and one was positive for both. However, of the 29 patients with anti-HCV, chronic liver disease developed in 5 (17%), including 1 patient who was positive for HBSAg. No patient had hepatocellular carcinoma. CONCLUSIONS: Perturbations of liver function were common in the kidney transplant recipients studied, most were self-limited, and few were associated with evidence of viral hepatitis. The risk of developing

A race-controlled human leukocyte antigen frequency analysis in lupus nephritis. The South-Eastern Organ Procurement Foundation.

Systemic lupus erythematosus (SLE) has higher incidence and mortality rates in addition to a greater risk for nephropathy in African Americans (blacks), compared with whites. We analyzed the South-Eastern Organ Procurement Foundation (SEOPF) database from 1982 through 1986 to determine if variation in human leukocyte antigen (HLA) frequencies, beyond those normally present between the races, were associated with lupus nephritis (LN). HLA antigen frequencies in 271 black and 230 white renal transplant recipients with LN as the cause of end-stage renal disease (ESRD) were compared with 4,506 race-matched cadaveric kidney donor controls. Odds ratios (ORs) and chi-square values were computed to assess the prevalence of each HLA phenotype among the cases versus the controls separately for blacks and whites. HLA-B8 and -DR2 frequencies were increased, and HLA-DR4 frequency was decreased in cases of both races compared with race-matched controls (race-combined ORs, 1.68, 1.46, and 0.49, respectively; all P < 0.01). Race-specific analyses showed that HLA-DR6 was decreased in black cases versus black controls (OR, 0.48; P < 0.001) and HLA-DR3 was increased in white cases versus white controls (OR, 1.88; P < 0.001). HLA-B8 and DR2 are positively associated and HLA-DR4 is negatively associated with LN in patients of both races. HLA-DR3 and -DR6 demonstrate race-specificity in LN and place whites at a disadvantage relative to blacks. It is likely that non-HLA-mediated genetic factors and/or environmental factors contribute to the increased risk of nephritis observed in black patients with SLE.(ABSTRACT TRUNCATED AT 250 WORDS)

Racial variation in human leukocyte antigen frequency in insulin-dependent diabetic nephropathy. The South-Eastern Organ Procurement Foundation.

Black patients with insulin-dependent diabetes mellitus are at increased risk for the development of diabetic nephropathy compared with white patients. To determine if genetic differences associated with the HLA system account for racial variation in insulin-dependent diabetes mellitus-induced nephropathy, serologically defined HLA phenotypes from renal transplant recipients and donors in the South-Eastern Organ Procurement Foundation database from 1982 to 1986 were analyzed. Renal transplant recipients (N = 1,531) with insulin-dependent diabetes mellitus-induced renal failure as the cause of ESRD (patients) were compared with 4,506 race-matched, nondiabetic cadaveric kidney donors (controls). Log-linear models were used to assess the relationship between insulin-dependent diabetes mellitus-induced renal failure and prevalence of each HLA phenotype. Bonferroni adjustments of P values were used to correct for multiple comparisons. A comparison of HLA frequencies in patients with insulin-dependent diabetes mellitus-induced renal failure demonstrated the presence of racial differences beyond those normally present between the black and white populations. Blacks, compared with whites, had increased frequencies of HLA-B62 (odds ratio [OR] black:white, 6.13:1.97; P < 0.02) and HLA-DR9 (OR black:white, 4.82:1.57; P < 0.008) and decreased frequencies of HLA-A1 (OR white:black, 1.56:0.8; P < 0.008) and HLA-DR3 (OR white:black, 4.9:2.82; P < 0.004). These results suggest that differences in HLA frequency may account, in part, for the observed racial variation in incidence of diabetic nephropathy. In addition, several antigens in positive and negative association with diabetic nephropathy were identified within each race.

Estradiol receptor and prognosis in human breast cancer and its metastases.

Follow-up of 86 patients for at least 40 months confirmed age dependency of receptor binding capacity in primary breast tumors but not in lymph node metastases. In most cases receptor binding capacity was higher in lymph node metastases than in primary tumors. Prognosis of the disease expressed as percentage of patients who survived and had a disease-free interval is related to receptor binding capacity of the primary tumors investigated. In our investigation, a value of 60 fmol/mg protein seems to be a suitable cut-off value to distinguish between breast cancer patients with good and bad prognosis. Receptor levels of lymph node metastases showed a similar behaviour as those of primary tumors related to percentage of patients who survived, but not to disease-free interval.

Maintenance of DQB1 polymorphisms in primates.

To understand the evolution of the class II major histocompatibility complex (MHC) DQB1 locus in primates, the second exons of seven DQB1 alleles from five non-human primate species were amplified by polymerase chain reaction. Comparisons of these and other primate sequences show that no between-species diversity is greater than within-species diversity, suggesting maintenance of DQB1 alleles through the history of Old-World primates. There is a preponderance of nonsynonymous nucleotide substitutions at antigen-binding-site codons; this pattern is in marked contrast to what is seen at the closely related, presumably nonfunctional DQB2 gene. The results support the hypothesis that DQB1 polymorphism is maintained by overdominant selection relating to antigen presentation.

Conservation of the HLA-DQB2 locus in nonhuman primates.

The evolutionary history of MHC class II genes is characterized by several examples of gene duplication, leading both to the creation of distinct subregions such as DR, DQ, and DP, as well as to duplicated loci within each of these subregions. In the human MHC, a prominent example of this diversification occurs within the HLA-DQ subregion, where the nonpolymorphic and transcriptionally "silent" DQB2 locus is highly homologous to the polymorphic expressed DQB1 locus. In order to gain some insight into the mechanisms constraining polymorphism at the DQB2 locus, the second exons of five nonhuman primate DQB2 alleles were sequenced. Six nonhuman primate DQB2 analogous sequences were obtained, two each from chimpanzee and owl monkey cell lines, and one each from gorilla and gibbon cell lines. Notably, the DQB2 sequences from the gibbon, gorilla, and one of the two chimpanzee sequences, although containing some silent nucleotide changes, encode a predicted DQB2 protein with 100% homology to the human DQB2 sequence. The owl monkey DQB2 allelic sequences and the other chimpanzee DQB2 sequence contain additional polymorphisms, but maintain approximately 95% nucleotide sequence identity with human and the other primate sequences. Identification of the owl monkey DQB2 locus indicates that the ancestral DQ gene duplication event occurred at least 40 million years ago, rather than 10 million years, as previously thought. Remarkably, nucleotide sequences from amplified cDNA indicate that the DQB2 gene, and not the DQB1 gene, may be transcribed in the owl monkey line. Substitutions occur at sites comparable to codons of well-recognized allelic variation in the functional DQB1 genes, implying that variation within the DQB2 locus operates under similar selection constraints to the DQB1 locus, with an extremely high degree of conservation through primate evolution.

Establishment and characterization of Macaca fascicularis lymphoblastoid cell lines.

A panel of cynomolgus macaque lymphoblastoid cell lines (LCL) was established by transforming peripheral blood mononuclear cells (PBMC) with Herpesvirus papio (HVP), and selected lines were examined by flow cytometry. Results indicate that HVP-transformed macaque LCL are phenotypically heterogeneous and resemble human Epstein-Barr virus (EBV)-transformed LCL in the abundant expression of major histocompatibility complex (MHC) class I and class II molecules. At least some lines are of B cell origin.

Racial differences in HLA antigen frequency and hypertensive renal failure.

Black patients with hypertension are six times more likely to develop end-stage renal disease than are their white counterparts. To determine if genetic differences associated with the Human Leukocyte Antigen (HLA) system account for racial variation in hypertensive renal failure, we examined antigenic frequencies from a large renal transplant registry. Human Leukocyte Antigen phenotypes from cadaveric renal transplant recipients and donors in the South Eastern Organ Procurement Foundation database from 1982 to 1986 were analyzed. One thousand six hundred four renal transplant recipients with hypertensive renal failure as the cause of end stage renal disease (cases) were compared with 4506 race-matched cadaveric kidney donors (controls). Log-linear models were used to assess the relationship between hypertensive renal failure and prevalence of each HLA phenotype. Bonferroni adjustments of P values were used to correct for multiple comparisons. Comparison of HLA frequencies between blacks and whites with hypertensive renal failure demonstrated that blacks had an increased frequency of HLA-DR3 beyond that normally known to exist between black and white populations. Black cases compared to black controls had an 8.6% increase in HLA-DR3 frequency contrasted with a 1.6% decrease in the frequency of this antigen between white cases and white controls. This absolute 10.2% difference between the races was significant (P = .02) because the control black and white populations had nearly identical frequencies for this antigen. White cases compared to white controls had lower HLA-A1 and B8 frequencies (21.2% v 30.6%, P = .0005 and 13.7% v 22.3%, P = .001, respectively) and a greater HLA-B35 frequency (20.7% v 14.2%, P = .02).(ABSTRACT TRUNCATED AT 250 WORDS)

Biochemical analysis of class I and class II MHC antigens in cynomolgus macaques by one-dimensional isoelectric focusing.

To obtain a better estimate of major histocompatibility complex (MHC) polymorphism in the Old World macaque, Macaca fascicularis, class I and class II MHC proteins from 42 animals were analyzed by sodium dodecyl sulfate polyacrylamide gel electrophoresis (SDS-PAGE) and one-dimensional isoelectric focusing (1D-IEF). The panel represented both related and unrelated animals with a total of at least 30 serologically distinct haplotypes. Cells were sequentially immunoprecipitated with monoclonal antibody (mAb) W6/32 for class I and with mAb L243 for class II molecules, followed by neuraminidase treatment. Both sets of immunoprecipitates yielded 5-7 major bands on IEF. All bands present in offspring were present in at least 1 parent. Siblings which were serologically identical for class I and which were non-stimulatory in mixed lymphocyte culture (MLC) yielded identical IEF patterns for both class I and class II; in other sibling pairs which were serologically identical for class I antigens (Ag), IEF produced convincing evidence that the siblings were indeed nonidentical, or helped to verify that recombination had occurred within the MHC. Specific bands were found which correlated with class I specificities A8, A24, and B25 previously defined by serology. Comparison of serological and biochemical data will broaden our understanding of the MHC in Macaca fascicularis and will increase the potential use of this species in transplantation research, as a model of disease, and for comparative studies.