Arginine at positions 13 or 70-71 in pocket 4 of HLA-DRB1 alleles is associated with susceptibility to tuberculoid leprosy.

Evaluation of human histocompatibility leukocyte antigen (HLA) class II genes in 54 cases of tuberculoid leprosy (TL) and 44 controls has shown a positive association with HLA-DRB1 alleles that contain Arg13 or Arg70-Arg71. Among TL patients, 87% carry specific alleles of DRB1 Arg13 or Arg70-Arg71 as compared to 43% among controls (p = 5 x 10(-6)) conferring a relative risk of 8.8. Thus, susceptibility to TL involves three critical amino acid positions of the beta chain, the side chains of which, when modeled on the DR1 crystal structure, line a pocket (pocket 4) accommodating the side chain of a bound peptide. This study suggests that disease susceptibility may be determined by the independent contribution of polymorphic residues participating in the formation of a functional arrangement (i.e., pocket) within the binding cleft of an HLA molecule.

The full induction of human apoprotein A-I gene expression by the experimental nephrotic syndrome in transgenic mice depends on cis-acting elements in the proximal 256 base-pair promoter region and the trans-acting factor early growth response factor 1.

To identify molecular factors regulating apo A-I production in vivo, we induced in transgenic mice the experimental nephrotic syndrome, which results in elevated levels of HDL cholesterol (HDL-C), plasma apo A-I, and hepatic apo A-I mRNA. Human (h) apo A-I transgenic mice with different length 5' flanking sequences (5.5 or 0.256 kb, the core promoter for hepatic-specific basal expression) were injected with nephrotoxic (NTS) or control serum. With nephrosis, there were comparable (greater than twofold) increases in both lines of HDL-C, h-apo A-I, and hepatic h-apo A-I mRNA, suggesting that cis-acting elements regulating induced apo A-I gene expression were within its core promoter. Hepatic nuclear extracts from control and nephrotic mice footprinted the core promoter similarly, implying that the same elements regulated basal and induced expression. Hepatic mRNA levels for hepatocyte nuclear factor (HNF) 4 and early growth response factor (EGR) 1, trans-acting factors that bind to the core promoter, were measured: HNF4 mRNA was not affected, but that of EGR-1 was elevated approximately fivefold in the nephrotic group. EGR-1 knockout (EGR1-KO) mice or mice expressing EGR-1 were injected with either NTS or control serum. Levels of HDL-C, apo A-I, and hepatic apo A-I mRNA were lowest in nonnephrotic EGR1-KO mice and highest in nephrotic mice expressing EGR-1. Although in EGR1-KO mice HDL-C, apo A-I, and apo A-I mRNA levels also increased after NTS injection, they were approximately half of those in the nephrotic EGR-1-expressing mice. We conclude that in this model, basal and induced apo A-I gene expression in vivo are regulated by the trans-acting factor EGR-1 and require the same cis-acting elements in the core promoter.

Genetic polymorphism of the human tumor necrosis factor region in insulin-dependent diabetes mellitus. Linkage disequilibrium of TNFab microsatellite alleles with HLA haplotypes.

The TNF region within the MHC includes a number of immunologically important genes. Microsatellites TNFa and TNFb adjacent to TNF exhibit extensive polymorphism. Employing a PCR-based technique, we identified TNFab haplotypes and defined their distribution in 97 controls and 48 diabetics of Caucasoid origin in a search for other genes within the MHC potentially associated with IDDM. Twenty-five different TNFab haplotypes were identified. A significant difference (p < 0.0005) in frequency between patients and controls was found for TNFa1b5 (relative risk 53). However, no other TNFab microsatellites demonstrated significantly different frequencies. Among diabetics TNFa1b5 was found to be in linkage disequilibrium with HLA-DR3-B18, a haplotype known to be associated with IDDM. Thus the increased frequency of TNFa1b5 among diabetics could reflect a linkage disequilibrium with a gene within the TNF region or with other genes, including the HLAs, which characterize this haplotype. In both controls and diabetics TNFa2b3 and TNFa7b4 were in linkage disequilibrium with DR3-B8 and DR7, respectively. Among diabetics, TNFa2b1 and TNFa6b5 were in linkage disequilibrium with DR4-B62 and DR4-B44, respectively. It is intriguing that TNFab haplotypes, represented by a short piece of about 200 nucleotides in the untranslated region upstream of TNF beta gene, maintain strong linkage disequilibria with different HLA haplotypes extending over 1 million base pairs. The identification of TNFab microsatellites exhibiting a high polymorphic index in a region lacking known polymorphic markers may provide potentially important information regarding the association of HLA haplotypes with autoimmune diseases, as they are in close proximity to other genes of immunologic importance.

Evidence for Hantavirus disease in Slovenia, Yugoslavia.

In Slovenia, North-Western part of Yugoslavia, 17 clinically documented Hantavirus disease cases (HVD) were serologically confirmed so far. Previously HVD was reported in the Southern part of Yugoslavia. By the indirect fluorescent antibody test (IFA), the prevalence of IgG class antibodies against different Hantaviral antigens was demonstrated in human sera collected in Slovenia. Three different reactivity patterns were observed. Majority of the IFA-positive human sera were confirmed by the immunoblot method. The distribution of Hantaviral infections was examined in small mammals captured in two natural foci of HVD, where clinical documented cases were reported. Hantaviral antibodies and antigens were demonstrated in C. glareolus, A. flavicollis, A. sylvaticus, and M. musculus.

[Kidney transplantation in the treatment of patients with end-stage renal failure]. / Transplantacija ledvic kot nadomestno zdravljenje bolnikov s koncno ledvicno odpovedjo.

Renal transplantation has become an acceptable mode of therapy for patients with end-stage renal failure since the early 1960s. Retrospective study was done to analyze clinical results od 126 patients who received either living related or cadaveric kidney. The cumulative graft survival rate was 90% one year and 80% four years after living related kidney transplantation. The corresponding patient survival rate was 96% one year and 94% four years after transplantation. There were no significant differences in graft and patient survival regarding mode of immunosuppressive therapy. In cadaveric kidney transplantation graft survival after one year was 78% and patient survival ranged at 98%. Our results are comparable to those of other centers and we think renal transplantation is adequate therapy for most patients with end-stage renal disease.

Arterial hypertension and renal allograft survival.

CONTEXT: Several observational studies have investigated the significance of hypertension in renal allograft failure; however, these studies have been complicated by the lack of adjustment for baseline renal function, leaving the role of elevated blood pressure in allograft failure unclear. OBJECTIVE: To examine the relationship between blood pressure adjusted for renal function and survival after cadaveric allograft transplantation. DESIGN: Nonconcurrent historical cohort study conducted from 1985 through 1997. SETTING: University teaching hospital. PARTICIPANTS: A total of 277 patients aged 18 years or older who underwent cadaveric renal transplantation without another simultaneous organ transplantation and whose allograft was functioning for a minimum of 1 year. Follow-up continued through 1997 (mean follow-up, 5.7 years). MAIN OUTCOME MEASURE: Time to allograft failure (defined as death, return to dialysis, or retransplantation) by systolic, diastolic, and mean arterial blood pressure measurements at 1 year after transplantation. RESULTS: Multivariate Cox proportional hazards modeling demonstrated that nonwhite ethnicity, history of acute rejection, and nondiabetic kidney disease were significant predictors of failure (P = .01 for all). In addition, the calculated creatinine clearance at 1 year had an adjusted rate ratio (RR) for allograft failure per 10 mL/min (0.17 mL/s) of 0.74 (95% confidence interval [CI], 0.62-0.88). The RR per 10-mm Hg increase in blood pressure measured at 1 year after transplantation, after adjustment for creatinine clearance, was 1.15 (95% CI, 1.02-1.30) for systolic pressure, 1.27 (95% CI, 1.01-1.60) for diastolic pressure, and 1.30 (95% CI, 1.05-1.61) for mean arterial pressure. Supplemental analyses that did not include death as a failure event or reduce the minimum allograft survival time for study subjects to 6 months yielded results consistent with the primary analysis. There was no evidence of modification of the blood pressure-allograft failure relationship by ethnicity or diabetes mellitus. CONCLUSIONS: Systolic, diastolic, and mean arterial blood pressures at 1 year posttransplantation strongly predict allograft survival adjusted for baseline renal function. More aggressive control of blood pressure may prolong cadaveric allograft survival.

HLA-B*0811: another example of a single point substitution of the HLA-B*0801 allele.

The described alle HLA-B*0811 is of Caucasoid origin. Most likely it derived from a point mutation of the B*0801 allele at position 559, where an adenine was converted to guanine. This position corresponds to codon 163 and resulted in an amino acid change from threonine to alanine. This substitution may influence both, T-cell interactions and/or peptide binding.

HLA-B*1559: a hybrid allele including exon 2 of HLA-B35 and exon 3 of HLA-B15 and serologically typed as B35.

The new allele HLA-B*1559 described is of Hispanic origin. This allele carries the exon 2 of HLA-B*35 alleles, and is identical to HLA-B*3501 and the exon 3 of HLA-B*1530. Serologically it is typed as B35. The most likely scenario for its generation seems to be a gene conversion event that involved the, frequent in Hispanic populations, B*1522 allele and a B*1530 allele. A segment of the B*1530 allele that included at least the sequences 412-419 would be transferred on a B*1522 background.

A subgroup of murine monoclonal anti-deoxyribonucleic acid antibodies traverse the cytoplasm and enter the nucleus in a time-and temperature- dependent manner.

BACKGROUND: The capacity of lupus autoantibodies to enter living cells and bind to molecules for which they have intrinsic affinity is not well appreciated. In previous studies, we identified a subgroup of three murine monoclonal IgG anti-DNA antibodies, derived from lupus-prone MRL-lpr/lpr mice, that localized within nuclei of cells in multiple organs and induced functional perturbations, in vivo, after passive transfer to normal mice. To examine the mechanisms of this phenomenon, we now extend these observations, using the same monoclonal anti-DNA antibodies and cultured cell lines. EXPERIMENTAL DESIGN: Multiple experimental approaches were utilized to track nuclear localization of anti-DNA antibodies, including direct immunofluorescence, confocal microscopy and immunoelectron microscopy. The requirements for nuclear localization were further evaluated quantitatively, in nuclei isolated from co-cultures of cells and 125I-Ig, under varying experimental conditions. RESULTS: Nuclear localization was observed with the same subset of anti-DNA antibodies that localized within nuclei in vivo; it was dependent on the antigen-binding region of the molecule; and it was not found with other anti-DNA antibodies. At progressive intervals, the Ig were observed: at the cell surface, within the cytoplasm, clustered at the nuclear pore, and within the nucleus. Nuclear localization of Ig was found to be a time- and temperature- dependent process, specific for a subset of anti-DNA antibodies and dependent on the antigen binding region of the Ig. CONCLUSIONS: This is the first demonstration that monoclonal autoantibodies can traverse both the cell and nuclear membranes to localize within the nuclei of cultured cells. Furthermore, nuclear localization of Ig was regulated in a manner analogous to that of other large cytoplasmic proteins that enter the nucleus. This confirms and extends our results using the same antibodies in whole animals, and it provides the basis to further examine the underlying mechanisms and consequences of this phenomenon.

Language guiding therapy: the case of dehydration versus volume depletion.

Indiscriminate use of the terms dehydration and volume depletion, so carefully crafted by our predecessors, risks confusion and therapeutic errors. These two conditions should be distinguished at the bedside and in how we speak to one another. Dehydration largely refers to intracellular water deficits stemming from hypertonicity and a disturbance in water metabolism. The diagnosis of dehydration cannot be established without laboratory analysis of p[Na +] or calculation of serum tonicity. In contrast, volume depletion describes the net loss of total body sodium and a reduction in intravascular volume and is best termed extracellular fluid volume depletion. The diagnosis of this condition relies principally on history, careful physical examination, and adjunctive data from laboratory studies. The pathophysiology of both dehydration and extracellular fluid volume depletion must be understood if these conditions are to be recognized and appropriately treated when they occur separately or together. There is no inclusive therapy for all situations. For example, indiscriminate treatment with 0.45% saline cannot be recommended when these conditions coexist because extracellular fluid volume depletion is often treated rapidly with 0.9% saline and dehydration is often treated more slowly with 5% dextrose.

DNA-based HLA typing of nonhematopoietic tissue used to select the marrow transplant donor for successful treatment of transfusion-associated graft-versus-host disease.

Transfusion-associated graft-versus-host disease (TAGVHD) is a rare and usually fatal complication of blood transfusion which can arise when immunocompetent lymphocytes from the donor of a cellular blood product are transfused into a severely immunocompromised recipient. We describe the case of an 8-month-old male with a severe combined immunodeficiency syndrome who developed TAGVHD after receiving an unirradiated transfusion. Serologic HLA typing of the parents, the patient, and the blood donor demonstrated the foreign origin of circulating lymphocytes, confirming the diagnosis of TAGVHD. The manifestations of TAGVHD did not respond to medical immunosuppressive therapy, and bone marrow transplantation was planned to treat the underlying immunodeficiency as well as the TAGVHD. By using DNA-based class I and class II HLA typing, the child's HLA type was determined from nonhematopoietic tissues. This information proved critical in selecting the bone marrow donor. The child received immunosuppression, myeloablation, and a T-depleted, maternal bone marrow graft mismatched at one HLA class II allele. Trilineage hematopoietic engraftment occurred within 3 weeks, and the child remains clinically stable with no evidence of TAGVHD more than 2 years after the transplant. This case illustrates that TAGVHD can be successfully treated by allogeneic bone marrow transplantation and that DNA-based HLA typing can play a unique role in the diagnosis and management of TAGVHD.

Ulcerative colitis in a renal transplant patient with previous Goodpasture disease.

A renal transplant was performed in a 6-year-old boy who developed end stage renal disease (ESRD) after presenting with antiglomerular basement membrane (anti-GBM) disease. At 10 years of age he developed ulcerative colitis while being immunosuppressed with cyclosporin, prednisone, and azothioprine. He had a pancolectomy, and at 14 years has no symptoms of ulcerative colitis or anti-GBM disease. HLA typing revealed that he was homozygous for HLA DR2. The co-occurrence of anti-GBM disease and ulcerative colitis has not previously been described. Although there is no known common etiology for these two autoimmune diseases, we propose that the patient's homozygosity at HLA DR2 may have predisposed him to both.