HLA antigens and cervical carcinoma.
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Biomedical subjects
Publications and source records attributed to E Thorsby.
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We studied whether antigen-specific T cells being restricted by the very similar HLA-Dw4 and/or -Dw14.1 molecules might demonstrate homogeneities in parts of their TCR. TCCs were generated from three individuals who were all HLA-Dw4/Dw14.1 heterozygous. Thirty-five TCCs specific for PPD or TT and restricted by HLA-Dw4 and/or -Dw14.1 were selected for TCR beta gene sequencing. We found that 19 different V beta genes from 13 V beta families were expressed by these TCCs. Thus, it seems that many different TCRV beta genes may be used by TCCs restricted by these HLA molecules. For PPD-specific TCCs, a possible biased usage of V beta 8, as well as possible preferential usage of a CDR3 motif, were found.
The susceptibility to develop celiac disease (CD) seems to be primarily associated to a particular HLA-DQ alpha/beta heterodimer encoded by the DQA1*0501 and DQB1*0201 alleles, in cis position on the DR3-DQ2 haplotype or in trans position by DR5-DQ7/DR7-DQ2 heterozygotes. However, exceptional patients exist who are neither DR3 nor DR5/DR7, particularly among Southern European populations. We therefore examined the DRB1, DQA1, and DQB1 alleles of 13 Spanish CD patients who were serologically typed to be neither DR3 nor DR5/DR7. Five patients were found to carry the DQA1*0501 and DQB1*0201 alleles either in cis or in trans position, three of them had previously been serologically mistyped. However, two of these patients carried DQA1*0501 and DQB1*0201 on haplotypes other than DR3 or DR5 in combination with DR7. One of the latter patients carried an unusual DR4-DQ2 haplotype, while another had an unusual DR8-DQ2 haplotype. Four of the remaining eight patients carried DR4-DQ8 haplotypes. Taken together, our findings provide further evidence that the DQ alpha/beta heterodimer encoded by the DQA1*0501 and the DQB1*0201 alleles confers the primary HLA-associated susceptibility to develop CD. However, our studies also corroborate that a second (and "weaker") HLA-associated CD susceptibility gene may be present on some DR4-carrying haplotypes.
Peptides derived from mutated human proto-oncogenes bound to HLA may represent a novel type of tumor-specific antigen. Mutated ras genes are the oncogenes most frequently identified in human cancer. The transforming genes carry a mutation in codons 12, 13, or 61. We have investigated whether the T-cell repertoire of healthy individuals contains T cells capable of recognizing and responding to oncogene-derived peptides. Synthetic peptides derived from mutated p21 ras proto-oncogenes, covering mutations at codons 12 or 13 were selected. It was feasible to elicit T-cell responses and isolate several new T-cell clones (TCC) with specificity for a number of different mutated ras peptides after repeated in vitro immunization. Four TCC were characterized with respect to fine specificity and HLA restriction. TCC B and I were restricted by HLA-DR molecules, and recognized the mutated p21 ras-derived peptide carrying Arg and Lys at residue 12, respectively. TCC E and F were restricted by HLA-DQ molecules, the former being specific for a mutated p21 ras-derived peptide with Val in position 13 and the latter more broadly reactive. Peptide competition experiments with a panel of ten peptides derived from p21 ras indicated that all could bind to HLA-DQ molecules of the T-cell donor, while several were also able to bind his HLA-DR molecules. These results show that several p21 ras mutations resulting in aa substitutions at residues 12 or 13 could be recognized by T cells derived from precursor T cells of relatively low frequency present in the normal repertoire of a single donor.
Point mutations in ras genes resulting in substitutions of amino acid Gly in positions 12 and 13, and Gln in position 61 of the ras gene product p21, are commonly found in human tumors. Peptides derived from aberrant p21 may elicit a tumor specific T cell response, provided that these peptides can bind to HLA molecules of the tumor and the patient has T cells able to recognize the corresponding peptide-HLA complex. Here we report that CD4+ T cells of memory type (CD45RO+) from a patient with a follicular thyroid carcinoma respond against a synthetic peptide derived from aberrant p21 ras having a Gln-->Leu substitution at position 61. Such responses were not observed when T cells from healthy volunteers or cancer patients where this mutation does not usually occur were stimulated with this peptide. The responding T cells did not cross-react with the corresponding peptide derived from native p21 ras nor did they recognize peptides carrying other substitutions in position 61. T cells clones were generated which recognized this Leu61 peptide when presented by HLA-DQ8 molecules. These T cell clones also recognized the corresponding intact p21 ras protein. By using several different synthetic peptides, a peptide with optimal stimulatory capacity was defined. Performing polymerase chain reaction and oligonucleotide probing we were, however, not able to detect the p21 ras gene encoding the Gln-->Leu substitution in DNA from tumor biopsies from the patient. This may indicate that tumor cells harboring the mutation leading to the Gln-->Leu substitution had been eliminated and that tumor progression was due to cells that had deleted the mutated ras gene. The finding that ras derived peptides and recombinant mutated p21 ras are immunogenic in man may form the basis for the development of cancer immunotherapy based on synthetic oncogene derived peptides.
To investigate whether T cells recognizing the same HLA molecule may demonstrate homology in parts of their TCR, five different HLA-DQw8-specific T lymphocyte clones (TLC) were studied. The TCR alpha and -beta genes of four alloreactive, HLA-DQw8-specific and one antigen-specific TLC were sequenced. All TLC used different V alpha and V beta genes. However, four of the TLC shared a certain CDR1 beta motif and all five used either J beta 2.3 or -2.5. In addition, two used the same J alpha. The results indicate a possible preferential usage of certain TCR structures by T cells specific for DQw8.
Two new TCRV beta coding region polymorphisms were identified: V beta 6.9a/b and V beta 21.4a/b. In both cases, a single nucleotide difference gives rise to an amino acid exchange. Genomic typing by the PCR/sequence-specific oligonucleotide probing technique was performed to study a possible contribution of these two new polymorphisms in susceptibility to autoimmune diseases. However, there was no association with insulin-dependent diabetes mellitus, rheumatoid arthritis, juvenile rheumatoid arthritis, multiple sclerosis, myasthenia gravis or coeliac disease. On the other hand, significant differences were found between Caucasoid and Oriental populations in frequencies of the V beta 6.9 and V beta 21.4 alleles.
A daughter of first cousins had two extremely rare, recessive disorders: thrombasthenia (Glanzmann's disease, glycoprotein IIb/IIIa deficiency) and mucopolysaccharidosis IIIB, (Sanfilippo B syndrome, alpha-N-acetylglucosaminidase (NAG) deficiency). Normal alpha-N-acetylglucosaminidase activity was observed in two obligate heterozygotes (the proband's father and her maternal grandmother), suggesting that in addition to the normal and defective alleles, a third, hyperactive allele is also present in this family. Such a hyperactive allele seems to be quite prevalent in our area, and makes the biochemical identification of heterozygotes impossible if no extensive family surveys provide additional clues. There was no linkage between the two diseases, nor between any of them and several blood-groups and HLA-antigens tested for.
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A high proportion of Staphylococcus aureus strains of human origin produce one or more exotoxins. In vivo, these toxins may give rise to a variety of clinical syndromes. In vitro, staphylococcal exotoxins have been shown to bind both to human leukocyte antigen (HLA) class II molecules on antigen-presenting cells and to the T-cell receptors on large fractions of T cells. The result of this interaction may be proliferation of the T cells, T-cell anergy, or apoptosis, depending on several factors, including the state of the responding cells and the presence of accessory molecules. Using naturally infected peripheral blood mononuclear cells depleted of CD8+ T cells, we have shown that staphylococcal exotoxins are powerful inducers of human immunodeficiency virus type 1 expression and that they induce expression at low concentrations and with greater efficiency than other T-cell mitogens. Human immunodeficiency virus type 1 was produced entirely by CD4+ T cells in this model; monocytes were expendable both as a source of virus and as a source of HLA class II molecules as long as other cells expressing HLA class II molecules were present. The results suggest that infection by S. aureus may be a cofactor in the immunopathogenesis of AIDS.
Insulin-dependent diabetes mellitus (IDDM), or type I diabetes, is the end result mainly of a T-cell mediated autoimmune destruction of pancreatic islet beta cells. Genetical and environmental factors are both of importance in the pathogenesis. Genes in the HLA complex seem to be the most important genetical factors. Among Blacks, Caucasoids and Orientals, IDDM susceptibility is associated with some particular combinations of DQA1 and DQB1 genes in cis or trans position. This strongly argues that susceptibility is primarily associated to the corresponding HLA-DQ molecules themselves. However, weaker contributions by other genes in the HLA complex cannot be excluded. Similarly, a dominant protection is strongly associated with some other DQ molecules, in particular HLA-DQ6, in all three ethnic groups. The function of HLA-DQ (and other class II) molecules is to present peptide-fragments of antigens to CD4+ T cells (mainly helper T cells). Thus, the recognition of certain islet beta cell derived peptides by self-reactive CD4+ T cells, may be an initial event in the pathogenesis. The DQ molecules involved in IDDM susceptibility or protection may exert their function either during thymic development of potential self-reactive CD4+ T cells, or by preferential presentation of certain beta-cell derived peptides to CD4+ T cells, or both. The finding that certain DQ molecules as such confer IDDM susceptibility may lead to new methods to prevent IDDM, for example by using blocking peptide analogues.
Data from the first 103 human heart transplantations performed on 100 recipients (aged 14-62 years) at a single center from November 1983 to January 1990 were analyzed in order to detect morbidity-causing risk factors. Cumulative one- and five-year graft survival was 82% and 68%. Multivariate analysis revealed three independent risk factors for early rejection, viz. HLA-DR and HLA-B mismatches and no prior cardiac surgery. Graft ischemic time exceeding 71 min was an independent risk factor for rejection, especially for moderate or severe events, and for infection. HLA-DR mismatch was an independent risk factor for moderate and severe rejection events and for infections. Finally, patients operated on because of end-stage ischemic heart disease were at significantly higher risk of rejection than those with other cardiac disorders. The study has several implications: Prospective tissue typing for cardiac transplantation and selection of donors may have an impact on graft function: Damage to the graft by prolonged ischemia may be reduced by improved organ preservation.
1. Of 2,003 patients starting renal replacement therapy for end-stage renal disease in Norway from 1983 through 1991, 83% were candidates for transplantation. The need for transplantations increased to 58 (50 first and 8 repeat) grafts PMP per year as the number of elderly patients increased. 2. There were 1,528 transplants performed at a rate increasing to 46 grafts PMP per year. The grafts were procured from LDs in 44% and CDs in 56%. Eighty percent of all patients in need were transplanted and 65% of all patients requiring replacement therapy for end-stage renal disease were treated by transplantation. The national waiting list and dialysis population remained almost stable. 3. Graft survival rates in recipients of first LD grafts (n = 593) were 91% and 77% at 1 and 5 years, respectively. One-year graft survival was 98% in HLA-identical grafts (n = 73), 91% in haploidentical grafts (n = 411), 89% in 2 haplotype-mismatched related grafts (n = 38), and 85% in spousal donor grafts (n = 71). Higher rates were observed in younger (< 55 yrs) patients. 4. Graft survival rates in recipients of first CD grafts (n = 688) were 78% and 59% at 1 and 5 years, respectively. The rates were 84% and 66% in younger (n = 342) versus 72% and 52% in older (> 55 years) (n = 346) patients. Death with a functioning graft caused approximately 45% and 75% of all graft losses in younger and older patients, respectively. Cardiovascular disease was the major cause of death.(ABSTRACT TRUNCATED AT 250 WORDS)
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CD34+ cells isolated from bone marrow or umbilical cord blood from healthy donors were studied for proliferation and differentiation in liquid cultures in the presence of recombinant human granulocyte-monocyte colony-stimulating factor (GM-CSF), granulocyte CSF (G-CSF), monocyte CSF (M-CSF), and interleukin-3 (IL-3), followed by immunophenotyping for myeloid and myeloid-associated cell surface markers. IL-3, either alone or together with GM-CSF, G-CSF, or M-CSF, induced, on average, 50-fold cell multiplication, GM-CSF five fold to 10-fold, and G-CSF and M-CSF less than fivefold. Cells from cultures stimulated with GM-CSF, G-CSF, or M-CSF alone contained cells with a "broad" myeloid profile, "broader" than observed in cultures with IL-3. However, since IL-3 induced rapid cell multiplication, high numbers of cells expressing early (CD13, CD33) and late myeloid markers (CD14, CD15) were recovered. The presence of other CSFs together with IL-3 did not alter the IL-3-induced effect on the cells. When 5,000 CD34+ cells were cultured with IL-3 alone, the cultures still contained 2,000 to 5,000 CD34+ cells after 14 days of culture, while cells cultured with GM-CSF, G-CSF, or M-CSF contained less than 1,000 CD34+ cells. Furthermore, 1,000 to 3,000 cells were positive for the megakaryocytic lineage marker CD41b after cultures with GM-CSF or IL-3, while cultures with G-CSF or M-CSF did not contain detectable numbers of CD41b+ cells. Finally, erythroid cells could also be generated from purified CD34+ cells. The results show that IL-3 and GM-CSF can induce rapid proliferation of purified CD34+ cells in vitro with differentiation to multiple myeloid lineages, while certain subsets maintain expression of CD34.
The absolute number of CD4+ and CD8+ T cells was counted directly in the blood of 75 healthy controls and 223 individuals infected with human immunodeficiency virus (HIV). The HIV-seropositive individuals were also classified clinically according to the system recommended by the Centers for Disease Control. We observed a pattern of changes in the T cell subset counts of the patient group. This pattern could be defined by five T cell stages ranging from normal T cell subset values to values representing severe T cell immunodeficiency. A close correlation was observed between the immunological and clinical classification of the patients. Quantification of T cell subsets may provide useful information in the follow-up of individuals infected with HIV, particularly in assessing the indications for antiviral therapy, and its effects.