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P Stastny

Publications and source records attributed to P Stastny.

At least 91 records · Page 5Linked to original sources
PubMed1991

DNA typing for HLA-DR, and -DP alleles in a Chinese population using the polymerase chain reaction (PCR) and oligonucleotide probes.

We have determined alleles of HLA-DRB1, DRB3, DRB5, DQA1, DQB1, and DPB1 loci in 91 unrelated healthy individuals from North China. Group-specific PCR primers were employed for the analysis of subsets of DR1, DR2, DR4, DRw52, and DPB. With allele-specific probes, 22 DRB1, 8 DQA1, 13 DQB1, and 12 DPB1 alleles were found in this panel. Allele frequencies showed that 25.3% of the subjects had DR7 and 26.4% had DR9, only 5.5% had DRB1*0301 (DRw17). In the DR4 group, DRB1*0405 (Dw15, 8.8%) and 0406 (KT2, 9.9%) were the most prevalent alleles. DRB1*0404 (Dw14.1), 0407 (Dw13.2) and 0408 (Dw14.2) were absent and the other alleles of the DR4 group were rare. The most common DRw6 subset was DRB1*1401 (8.8%). DRB1*0802 and 0803 were present (2.2%, 6.6%), and DRB1*0801 was not found. Associations with DQA1 and DQB1 were generally similar to those found in other populations. DPB1*0501 was the most frequent (60.2%) allele at the DPB1 locus. Overall our study shows that the distribution of class II alleles in a population from Mainland China is quite different from other ethnic groups. The high frequency of the KT2 subset of DR4. (DRB1*0406) and of DPB1*0501 are the most striking features found. A new type of DR4 was determined in one subject. It was like DR4-Dw15 (DRB1*0405) but, according to our hybridization patterns, it encoded valine instead of glycine in position 86. It is now called DRB1*0410.

Alleles↗
PubMed1991

Rheumatoid arthritis in Israeli Jews: shared sequences in the third hypervariable region of DRB1 alleles are associated with susceptibility.

Rheumatoid arthritis (RA) is known to be associated with class II HLA antigens in most populations, but recent studies in Israeli Jewish patients showed no significant differences in either DR4 or DR1 between patients and controls. In a previous DR4 subset study we found DR4-Dw15 to be associated with susceptibility (RR = 9.2) but this allele occurred in only 12% of the patients. We analyzed all DRB1 genes, using the polymerase chain reaction (PCR) and hybridization with allele specific oligonucleotides, in 49 Jewish patients with RA and 40 normal Jewish controls. Six DRB1 alleles that are similar to the prototype DR4-Dw4 (DRB1*0401) appeared to contribute to the risk for developing RA. In addition to DR4-Dw15 (DRB1*0405) 2 other alleles having substitutions in codons 71 only (DR1-Dw1/DRB1*0101, DR4-Dw14.2/DRB1*0408) or in codons 70 and 71 (DRw10/DRB1*1001) gave highly significant relative risks. Together, this group, with valine in position 85, and glycine in codon 86, gave a relative risk of 11.0 (p = 0.0002). Two other alleles with the same sequence in the third hypervariable region (amino acids 67-74) but with valine in codon 86 (DR4-Dw14.1/DRB1*0404) or alanine in 85 and valine in 86 (DR1-Dw20, DRB1*0102) gave a combined risk of 3.6 (p = 0.049). Altogether these 7 alleles with similar sequences in the third hypervariable region accounted for 55.6% of the patients, with an overall relative risk of 8.6 (p = 0.00002). Our results in this population indicate that shared epitopes in the third hypervariable region of DRB1 alleles also play a role in susceptibility to RA.(ABSTRACT TRUNCATED AT 250 WORDS)

Alanine↗
PubMed1991

Clinical relevance of antibodies to non-HLA antigens in organ transplantation.

This article summarizes work that focuses on alloantibodies that bind to endothelial cells and attempts to provide an evaluation of the apparent role that antigens distinct from classic HLA alleles, and not expressed in lymphocytes, may play in kidney transplant rejection. The most recent experience with the donor-skin crossmatch in prediction of early kidney allograft rejection also is described.

Endothelium, Vascular↗
PubMed1990

Analysis of HLA-DQ genotypes and susceptibility in insulin-dependent diabetes mellitus.

There is evidence that certain alleles at the HLA-DQ locus are correlated with susceptibility to insulin-dependent diabetes mellitus (IDDM) and in particular that DQ beta-chain alleles containing aspartic acid at position 57 are protective. The availability of a large group of patients with IDDM enabled us to assess the role of HLA-DQ alleles in susceptibility to the disease in order to confirm and extend recent observations derived from studies of smaller numbers of patients. Using allele-specific oligonucleotide probes and the polymerase chain reaction, we studied 266 unrelated patients with IDDM and 203 unrelated normal subjects for eight HLA-DQ beta-chain alleles. Two major findings emerged from these studies. First, the presence of an HLA-DQw1.2 allele was protective. Only 6 of the 266 patients with IDDM (2.3 percent) were positive for HLA-DQw1.2, as compared with 74 of the 203 normal subjects (36.4 percent; P less than 0.001). Thus, persons with the HLA-DQw1.2 allele, which is one of the polymorphic forms of the beta chain of the HLA-DQ molecule, rarely had IDDM, no matter which other HLA-DQ beta-chain allele they inherited ("dominant protection"). Second, the presence of the HLA-DQw8 allele increased the risk of IDDM. The relative risk of IDDM was 5.6 in persons homozygous for HLA-DQw8, and it was similar in persons with the HLA-DQw1.1/DQw8 or HLA-DQw2/DQw8 haplotype ("dominant susceptibility"). However, the relative risk of IDDM in persons who had the HLA-DQw1.2/DQw8 haplotype was 0.37, demonstrating that the protective effect of HLA-DQw1.2 predominated over the effect of HLA-DQw8. We conclude that the presence of the HLA Class II antigen DQw1.2 is strongly protective against the development of IDDM, and that complete HLA-DQ typing is necessary for accurate assessment of susceptibility to IDDM.

Adult↗
PubMed1990

HLA-DR alleles with naturally occurring amino acid substitutions and risk for development of rheumatoid arthritis.

To determine the HLA-DR4 subtypes associated with rheumatoid arthritis (RA), we performed amplification of DR4 DRB1 genes by the polymerase chain reaction and dot-blots with oligonucleotide probes. In 52 HLA-DR4+ RA patients, Dw4 was the predominant subtype. This subtype was found in 45 of 52 patients (86.5%) compared with 33 of 59 DR4+ controls (55.9%; P less than 0.001). In the whole population, Dw4 also gave the highest relative risk for RA (RR = 5.31). Relative risk was also associated with DR1.1, the common white DR1 (Dw1) type, which has a third hypervariable region amino acid sequence similar to some forms of DR4 and has glycine at position 86. Variants of DR1 (DR1.2) or DR4 (Dw13.1, Dw14.1) with valine at position 86 appeared less able to confer risk for RA. Substitution of residues in the third hypervariable region of the first domain of DRB1 appeared to correlate with relative risk for RA. Among subjects having 0-1 amino acid substitutions, RA developed in 53%, whereas in subjects with 2-4 amino acid changes, RA was present in only 17.4% (P less than 0.00001). DQw7 (formerly DQw3.1) was slightly increased in DR4+ RA patients compared with controls, but a striking excess of Dw4,DQw7 homozygous patients was observed. The results suggest that DQw7 may have an additional effect, possibly with a recessive mechanism, since it was observed only in DR4 homozygous patients.

Alleles↗
PubMed1990

HLA antigens in juvenile arthritis. Pauciarticular and polyarticular juvenile arthritis are immunogenetically distinct.

Using DNA techniques, we investigated the role of HLA-DR, DQ, and DP alleles in susceptibility to juvenile arthritis (JA). We studied 2 groups of patients with JA having a different disease prognosis and course. The pauciarticular form is usually benign, while the polyarticular disease frequently leads to joint destruction and disability. Persistent pauciarticular disease developed preferentially in patients having HLA-DRw13-Dw18 and DQw6-Dw18, but these antigens did not confer susceptibility in patients whose disease converted to the polyarticular form. HLA-DPw2.1 was an additional susceptibility factor for patients with JA of pauciarticular onset. In the polyarticular form of JA, HLA-DPw3 was the major factor for susceptibility, giving a relative risk of 10.3 (P less than 0.0001). In addition, we found that DRw8.1 and DQw4 were increased, and HLA-DR4 was markedly decreased, in patients with pauciarticular and polyarticular disease. These results indicate that in addition to some shared factors, distinct HLA class II alleles are important in pauciarticular or polyarticular JA. We conclude that typing with oligonucleotide probes may be useful in predicting the outcome in some children with arthritis.

Adolescent↗
PubMed1990

DNA typing for class II HLA antigens with allele-specific or group-specific amplification. I. Typing for subsets of HLA-DR4.

DNA sequences that distinguish the subsets of HLA-DR4 are also found on several other alleles. This makes typing of heterozygotes with oligonucleotide probes quite impractical. We have therefore developed a procedure in which, in a first step, DNA of the genes to be analyzed is amplified selectively, using group-specific primers. In the case of DR4-DRB1, a primer matching codons 5 to 13 when used in the polymerase chain reaction resulted in products that were entirely suitable for typing for the DR4 subsets. Using appropriate probes, eight distinct subsets were identified. However, only six of them were represented in a normal North American Caucasian panel. In conjunction with a method for rapid DNA extraction, the procedure offers a simple, highly specific and reproducible method for determining subtypes of HLA-DR4 that at present cannot be recognized by serologic methods.

Alleles↗
PubMed1990

DNA typing for class II HLA antigens with allele-specific or group-specific amplification. II. Typing for alleles of the DRw52-associated group.

Codons 9-12 of the first domain of DRB1, which encode the amino acid sequence EYST (in single-letter code), served as the basis for the construction of a polymerase chain reaction primer specific for DRB1 of the whole DRw52 group. Using this primer for the 5' end and a primer for a conserved region at the 3' end, we could amplify selectively the DRB1 genes of DRw17-, w18-, w11-, w13-, w14, and w8-positive haplotypes. DRB3 genes of DR3,DR5 and DRw6 were also specifically amplified, separately. This selectively amplified DNA could then be used in a blotting procedure for hybridization with oligonucleotide probes chosen to define the polymorphisms that characterize these alleles and their subsets. Patterns of hybridization for groups of related specificities have been described, and their frequencies were determined in representative panels available in our laboratory. The results presented illustrate the extraordinary power of this new DNA typing procedure. Using these relatively simple methods it is possible to define, with certainty, allelic forms of DRB1 and DRB3 associated with the DRw52 group. The ability to type extends far beyond the capabilities of present serology; the precision achieved with this method in panel typings is unprecedented.

Alleles↗
PubMed1989

Prediction of early kidney transplant rejection by a crossmatch with donor skin.

Immunofluorescence staining of donor skin with recipient serum was performed in 25 patients undergoing kidney transplantation. Transplants were performed when cytotoxicity T cell crossmatches with long incubation and with antiglobulin enhancement were negative. In 20 patients the skin crossmatch was negative and all had an uneventful course. In 5 other recipients, the crossmatch with skin was positive and all developed severe rejection 1-8 days after transplantation. The correlation between skin crossmatch and early rejection was statistically highly significant (P less than 0.00001). Rejection in the skin-crossmatch-positive group led to graft loss in 3, and chronic rejection with poor residual function in the other 2 patients. Serum creatinine at one month was in the 2.6-5.0 mg/dl range in these two patients, while in the group with negative skin crossmatches 15 had serum creatinine levels of less than 1.6, and 5 were in the 1.6-2.5 mg/dl range. Although the nature of the skin antigen is unknown, it appears that this crossmatch procedure was highly accurate in predicting early kidney transplant rejection.

Fluorescent Antibody Technique↗
PubMed1988

Class II human leukocyte antigen genes and T cell receptor polymorphisms in patients with rheumatoid arthritis.

Human leukocyte antigen (HLA) typing was performed in 174 patients with rheumatoid arthritis and 222 white control subjects. Increases in HLA-DR4 and HLA-DR1 were observed as in previous studies. Each of these appeared to be inherited as dominant risk factors. Southern blotting with a DR-beta probe after digestion of genomic DNA with the restriction enzyme Bam HI showed seven bands. Three of them correlated with DR4 and were increased in rheumatoid arthritis patients. Subsets of DR4 were determined by polymerase chain reaction amplification followed by hybridization with oligonucleotide probes. Dw4 was increased in rheumatoid arthritis patients, and the frequency of the other subsets appeared to be similar in rheumatoid arthritis patients and control subjects. A polymorphism associated with the T cell receptor V-beta-8 gene family was significantly increased in rheumatoid arthritis patients.

Arthritis, Rheumatoid↗
PubMed1988

Associations of HLA-DR4 with rheumatoid factor and radiographic severity in rheumatoid arthritis.

Possible associations between HLA-DR4 and laboratory, radiographic, joint count, functional, and demographic measures of clinical status were analyzed in 154 white patients with rheumatoid arthritis. Overall, 65 percent of the patients were HLA-DR4 positive, similar to other series. HLA-DR4 was associated significantly with the presence of rheumatoid factor and more severe radiographic changes. HLA-DR4 was not associated with significant differences in demographic, joint count, or functional measures of clinical status. HLA-DR1 was not associated significantly with differences in the presence of rheumatoid factor, radiographic changes, or other measures of clinical status. Selective associations of HLA-DR4 with rheumatoid factor and radiographic scores were more marked in men than in women. Patients who were putatively homozygous for HLA-DR4 were all seropositive and had more severe radiographic changes than patients who were heterozygous for HLA-DR4.

Activities of Daily Living↗
PubMed1988

HLA-DR4 and other genetic markers in rheumatoid arthritis.

In a new series of RA patients the association with HLA-DR4 was again found to be highly significant. Also increased were the DR4 associated antigens DRw53 and DQw3. Hybridization of a DQ-beta probe to Bg1 II-digested DNA showed that a variant of DQw3, characterized by a 4.3 kb fragment and related to the serological specificity TA10, was markedly increased among DR4 positive RA patients. HLA-DR1 was also increased in RA and appeared to be independent of the increase of DR4. Although the DR1 association was weaker, it was observed in both patients with and without RF. In contrast, DR4 was found to be increased significantly only in the RF positive group of patients, as previously observed. Development of RA in multiple-case families was found to be linked to the inheritance of DR4 positive haplotypes. The possible role of risk factors associated with polymorphic markers of the T-cell receptor genes was investigated. An allelic marker associated with one of the variable gene subfamilies of the beta-chain was found to be associated with RA. The results suggest that susceptibility for development of RA is influenced by alleles of the T-cell receptor in conjunction with the class II HLA factors with which the T-cell receptor interacts in the course of the immune response.

Alleles↗
PubMed1988

Allogeneic lymphocyte stimulation by human spleen. Identification of cells that are very effective for presenting class II HLA antigens.

Human spleen cells were fractionated by percoll density gradient centrifugation and by sorting in the FACS with mixtures of fluorescent antibodies against T cells, B cells, monocytes, and Sig-bearing cells. Cells responsible for powerful MLR stimulation were class II HLA antigen-positive and were concentrated in preparations depleted of all the markers listed above. These cells represented 1-2% of the initial spleen cells. They were remarkably more active than other HLA class II antigen-positive cells. The procedure described allows rapid enrichment for the responsible cells. It should be useful for further characterization of these cells and for performing studies on their function.

Antigen-Presenting Cells↗
PubMed1987

HLA-D region epitopes associated with juvenile arthritis. Recognition by alloreactive T cell clones and alloantisera.

The HLA-D region antigens DR5 (w11,w12), DRw6 (w13,w14), DRw8, DRw52, and DQw1 have previously been shown to be increased in frequency in subsets of patients with juvenile arthritis. Since the HLA-D region is complex (composed of at least 3 subregions encoding multiple molecules, each in turn presenting multiple alloantigenic epitopes), we sought to clarify whether one strongly associated factor might explain the previous findings. To search for the pertinent HLA-D region stimulatory epitopes, alloreactive T cells were primed against DR5 and DRw6 haplotypes and cloned by limiting dilution. Three T cell clones and 1 alloantiserum met the criteria for significant association with juvenile arthritis on patient testing, including DR5, DRw6, and DRw8 haplotypes. Monoclonal antibody blocking revealed that all 4 recognized epitopes on DR subregion products. For 2 of the clones, the relative risks for JA (10.5 and 9.4) were higher than the risks with any other previously described typing reagents.

Antibodies, Monoclonal↗
PubMed1987

High levels of in vitro IgM rheumatoid factor synthesis correlate with HLA-DR4 in normal individuals.

The association between the HLA-DR4 histocompatibility antigen and in vitro synthesis of IgM and IgM rheumatoid factor (IgM-RF) by blood mononuclear cells was investigated in 35 normal subjects. In vitro cultures of T and B cells were stimulated with pokeweed mitogen, and the secreted IgM-RF, tetanus antibody, and total IgM protein were measured by solid-phase radioimmunoassay. In cultures containing unseparated T cells, IgM-RF production in the DR4+ and DR4- subgroups was not significantly different. However, depletion of OKT8+ cells containing T suppressor cells resulted in significantly higher IgM and IgM-RF synthesis in the DR4+ subgroup. Moreover, 6 of the 8 highest levels of IgM-RF were produced by DR4+ individuals, while only 7 of the remaining 27 individuals were DR4+ (P = 0.035). Ratios of secreted IgM-RF:IgM indicated that there was a relative enrichment for IgM-RF- specific B cell precursors in DR4+ high responders, although total numbers of circulating B cells were not increased. High responder B cells had high levels of responsiveness when mixed with T helper cells from low responders, whereas low responder B cells consistently produced low responses, even when cocultured with T helper cells from high responder donors. The data suggest that a subset of normal individuals has a pokeweed mitogen-responsive lymphocyte population that contains a B cell subpopulation specific for IgM-RF synthesis and that this condition is associated with HLA-DR4. In certain individuals who have the DR4 type, there may be a component of a susceptible genetic background, upon which other factors act to induce IgM-RF synthesis and which may produce clinical manifestations of rheumatoid arthritis.

Adult↗