Novel and Haplotype Specific MicroRNAs Encoded by the Major Histocompatibility Complex

The MHC is recognized for its importance in human health and disease. However, many disease-associated variants throughout the region remain of unknown significance, residing predominantly within non-coding regions of the MHC. The characterization of non-coding RNA transcripts throughout the MHC is thus central to understanding the genetic contribution of these variants. Therefore, we characterize novel miRNA transcripts throughout the MHC by performing deep RNA sequencing of two B lymphoblastoid cell lines with completely characterized MHC haplotypes. Our analysis identifies 89 novel miRNA transcripts, 48 of which undergo Dicer-dependent biogenesis and are loaded onto the Argonaute silencing complex. Several of the identified mature miRNA and pre-miRNA transcripts are unique to specific MHC haplotypes and overlap common SNPs. Furthermore, 43 of the 89 identified novel miRNA transcripts lie within linkage disequilibrium blocks that contain a disease-associated SNP. These disease associated SNPs are associated with 65 unique disease phenotypes, suggesting that these transcripts may play a role in the etiology of numerous diseases associated with the MHC. Additional in silico analysis reveals the potential for thousands of putative pre-miRNA encoding loci within the MHC that may be expressed by different cell types and at different developmental stages.

16(th) IHIW: global distribution of extended HLA haplotypes

This report describes the project to identify the global distribution of extended HLA haplotypes, a component of 16th International HLA and Immunogenetics Workshop (IHIW), and summarizes the initial analyses of data collected. The project aims to investigate extended HLA haplotypes, compare their distribution among different populations, assess their frequency in hematopoietic stem cell unrelated donor registries and initiate an international family studies database and DNA repository to be made publicly available. HLA haplotypes compiled in immunogenetics laboratories during the evaluation of transplant candidates and related potential donors were analysed. Haplotypes were determined using the pedigree analysis tool publicly available from the National Marrow Donor Program (NMDP) website. Nineteen laboratories from 10 countries (11 laboratories from North America, five from Asia, two from Latin America and one from Australia) contributed data on a total of 1719 families comprised of 7474 individuals. We identified 10393 HLA haplotypes, of which 1682 haplotypes included high-resolution typing at HLA-A, B, C, DRB1 and DQB1 loci. We also present haplotypes containing MICA and other HLA loci and haplotypes containing rare alleles seen in these families. The project will be extended through the 17th IHIW, and investigators interested in joining the project may communicate with the first author.

16(th) IHIW : review of HLA typing by NGS

Human leucocyte antigen (HLA) genes play an important role in the success of organ transplantation and are associated with autoimmune and infectious diseases. Current DNA-based genotyping methods, including Sanger sequence-based typing (SSBT), have identified a high degree of polymorphism. This level of polymorphism makes high-resolution HLA genotyping challenging, resulting in ambiguous typing results due to an inability to resolve phase and/or defining polymorphisms lying outside the region amplified. Next-generation sequencing (NGS) may resolve the issue through the combination of clonal amplification, which provides phase information, and the ability to sequence larger regions of genes, including introns, without the additional effort or cost associated with current methods. The NGS HLA sequencing project of the 16IHIW aimed to discuss the different approaches to (i) template preparation including short- and long-range PCR amplicons, exome capture and whole genome; (ii) sequencing platforms, including GS 454 FLX, Ion Torrent PGM, Illumina MiSeq/HiSeq and Pacific Biosciences SMRT; (iii) data analysis, specifically allele-calling software. The pilot studies presented at the workshop demonstrated that although individual sequencers have very different performance characteristics, all produced sequence data suitable for the resolution of HLA genotyping ambiguities. The developments presented at this workshop clearly highlight the potential benefits of NGS in the HLA laboratory.

A multi-site study using high-resolution HLA genotyping by next generation sequencing

The high degree of polymorphism at human leukocyte antigen (HLA) class I and class II loci makes high-resolution HLA typing challenging. Current typing methods, including Sanger sequencing, yield ambiguous typing results because of incomplete genomic coverage and inability to set phase for HLA allele determination. The 454 Life Sciences Genome Sequencer (GS FLX) next generation sequencing system coupled with conexio atf software can provide very high-resolution HLA genotyping. High-throughput genotyping can be achieved by use of primers with multiplex identifier (MID) tags to allow pooling of the amplicons generated from different individuals prior to sequencing. We have conducted a double-blind study in which eight laboratory sites performed amplicon sequencing using GS FLX standard chemistry and genotyped the same 20 samples for HLA-A, -B, -C, DPB1, DQA1, DQB1, DRB1, DRB3, DRB4, and DRB5 (DRB3/4/5) in a single sequencing run. The average sequence read length was 250 base pairs and the average number of sequence reads per amplicon was 672, providing confidence in the allele assignments. Of the 1280 genotypes considered, assignment was possible in 95% of the cases. Failure to assign genotypes was the result of researcher procedural error or the presence of a novel allele rather than a failure of sequencing technology. Concordance with known genotypes, in cases where assignment was possible, ranged from 95.3% to 99.4% for the eight sites, with overall concordance of 97.2%. We conclude that clonal pyrosequencing using the GS FLX platform and CONEXIO ATF software allows reliable identification of HLA genotypes at high resolution.

Identification of a novel HLA-B*35 variant allele, B*35:151

HLA-B*35:151 differs from HLA-B*35:68:02 by one nucleotide at codon 116 (TCC>TTC) resulting in an amino acid substitution, serine to phenylalanine.

HLA and environmental interactions in sarcoidosis

Sarcoidosis is a systemic granulomatosis of unknown etiology despite being described over 100 years ago. While both genetic predisposition and environmental exposures have been proposed as playing a role in this disease, there have not been any systematic investigations of gene-environmental interaction in this disease. In the ACCESS dataset, detailed environmental histories and high resolution HLA class II typing were performed on 476 cases of newly diagnosed sarcoidosis and 476 matched controls from the patients' community. We evaluated gene-environmental interactions in exposures or HLA class II alleles that were present in > 5% of the population and had an odd ratio of > 1.0. Four exposures and four HLA Class II alleles met these criteria and were evaluated. Significant interaction was observed between HLA DRB1*1101 and insecticide exposure at work (p < 0.10) and suggestive interaction was observed between HLA DRB1*1101 and exposure to mold and musty odors and DRB1*1501 and insecticide exposure at work (P < 0.15). In addition, HLA DRB1*1101 and insecticide exposure at work was associated with extrapulmonary sarcoidosis, specifically cardiac sarcoidosis and hypercalcemia (p<0.05) and HLA DRB1*1101 and exposure to molds and musty odors was associated with pulmonary only sarcoidosis (P < 0.05). These studies suggest that sarcoidosis is due to an interaction of genetic predisposition and environmental exposure in at least some cases of sarcoidosis. Future studies in defined phenotypes of sarcoidosis may be necessary to define environmental and genetic associations with sarcoidosis.

Identification of a novel HLA-DPB1 allele (DPB1*1902) by haplotype-specific extraction and nucleotide sequencing

The DPB1*1902 allele resulted from a single-nucleotide substitution at codon 35 (TTC --> CTC/F --> L) of exon 2 of DPB1*0402 or 0602.

Unrelated donor or partially matched related donor peripheral stem cell transplant with CD34+ selection and CD3+ addback for pediatric patients with leukemias

Unmodified peripheral stem cell transplants are associated with an increased risk of extensive chronic GVHD. T depletion may reduce this risk, but the risk of graft failure or relapse may increase. To decrease the risks of both extensive chronic GVHD and graft failure, we added back a defined dose of CD3+ cells to CD34+ selected PSCs. Twenty-four patients were evaluable for outcome analysis. Donors were unrelated (23) or related (1). Conditioning was thiotepa, cyclophosphamide, and total body irradiation. Cyclosporine was used post transplant. Following CD34+ selection, a total of 5 x 10(5)/kg CD3+ cells were infused. Donors were matched for 12 patients. The median CD34+ dose infused was 7.1 x 10(6)/kg. Engraftment occurred in all patients at a median of 14 days (10-19). Twelve patients are alive in remission 15-34 months (median, 25) post PSCT. GVHD occurred in 17 patients, but was >grade II in only 2. Chronic GVHD occurred in 61.5% of evaluable patients, but was limited to skin and perioral cavity. Two patients relapsed, and 10 patients died of non-relapse causes. This study demonstrates that PSCT with CD34+ selection and a defined dose of CD3+ results in prompt engraftment and may limit development of extensive chronic GVHD.

Outcomes of transplantation with partial T-cell depletion of matched or mismatched unrelated or partially matched related donor bone marrow in children and adolescents with leukemias

Graft-versus-host disease (GVHD) remains a major barrier to successful hematopoietic stem cell transplant for patients who lack a matched related donor. Partial T-cell depletion (TCD) of the graft may decrease the risk of severe GVHD with unrelated donors (URD) and partially matched related donors (PMRD) while retaining an antileukemic effect. We analyzed our experience using URD and PMRD for pediatric patients with leukemias from 1990 to 2001. A subgroup of 'matched' URD donor pairs was retrospectively analyzed for high-resolution class I. Partial TCD was accomplished with monoclonal antibody T10B9 or OKT3 and complement. There were 76 URD (45% matched) and 28 PMRD recipients. Event-free survival (EFS) was 38.3%, and overall survival (OS) 45.1% at 3 years. On multivariate analysis, there was no difference in survival based upon marrow source, but nonrelapse mortality was higher with the use of PMRD. Relapse occurred in 6% of ALL patients, and 22.8% of AML/MDS patients. Grades III-IV GVHD was observed in only 6.7% of patients. Partial TCD allows use of matched or mismatched URD, or PMRD with little mortality from GVHD, durable engraftment, and no increase in relapse risk.

Unrelated donor bone marrow transplantation for children with severe aplastic anemia: minimal GVHD and durable engraftment with partial T cell depletion

Both increased graft rejection and increased graft vs host disease (GVHD) remain obstacles to success for unrelated donor (URD) BMT for patients with SAA. Partial T cell depletion (PTCD) may decrease the risk of severe GVHD, while still maintaining sufficient donor T lymphocytes to ensure engraftment. We report on 12 patients with SAA who underwent PTCD URD BMT. All patients had failed medical therapy or relapsed following initial responses, and were transfusion dependent. The median age was 6 years, and there were five males. Donors were matched for four patients, and mismatched for eight. All patients received total body irradiation with either Ara-C or thiotepa and cyclophosphamide. PTCD was accomplished using monoclonal antibody T10B9 or OKT3 and complement. All patients engrafted, with a median time of 18 days to ANC >500. Only one patient had greater than grade II acute GVHD; two patients had limited and one patient extensive chronic GVHD. Nine patients are alive and transfusion independent at a median months post BMT. Three patients died from infection or renal failure. This series suggests that an aggressive immunosuppressive conditioning regimen with PTCD results in successful engraftment and minimal GVHD in pediatric patients with SAA, even with HLA mismatched donors.

Identification of kappa and lambda chains of the major immunoglobulin G subclasses by capillary zone electrophoresis

Immunoglobulins are present in most tissues and plasma and play crucial role in immune system. Alteration of the levels of the immunoglobulin G (IgG) subclasses (IgG1, IgG2, IgG3 and IgG4) is an indication of a disturbed immunological response. The aim of the present study was the development of a capillary electrophoresis (CE) method for the analysis of IgG subclasses in respect to their variable kappa and lambda chains. Various analytical conditions and CE modes, including capillary zone electrophoresis (CZE), capillary isoelectric focusing (CIEF) and micellar electrokinetic capillary chromatography (MECC) have been thoroughly studied. CZE was found to be the most convenient way to separate IgG subclasses. Three of the human IgG subclasses were resolved using uncoated fused-silica and 50 mM phosphate, pH = 9.3, as operating buffer at 20 kV and detection at 214 nm. IgG1kappa was completely separated from IgG2kappa and IgG3kappa, whereas IgG2kappa co-migrated with IgG4kappa, which is the minor IgG subclass. Under the same conditions IgG4lambda was completely separated from IgG1lambda, IgG2lambda and IgG3lambda, enabling the identification of the various lambda chains. The developed CE method is rapid and can be applied to the identification of the major immunoglobulin G subclasses in respect to their variable kappa and lambda chains.

Validation of DNA-based HLA-A and HLA-B testing of volunteers for a bone marrow registry through parallel testing with serology

A total of 42,160 individuals were typed for HLA-A and HLA-B by both serology and PCR-based typing. The HLA assignments included all of the known serological equivalents. The majority of the individuals (99.9%) were from U.S. minority population groups. The serologic typing was performed between 1993 and 1997 at the time of recruitment for the National Bone Marrow Program (NMDP) registry. The polymerase chain reaction (PCR)-based typing was carried out in two phases. In phase I, DNA typing was performed by PCR using sequence-specific oligonucleotide probes (PCR-SSOP) or PCR using sequence-specific primers (PCR-SSP) without knowledge of the serologic assignments. Discrepancies were identified between the serologic and DNA assignments in 24% of the volunteers (8% of volunteers differed for only HLA-A assignments, 13% for HLA-B, and 3% for both HLA-A and -B) and a potential explanation was assigned each discrepant serology/DNA pair. In phase II, a random sampling scheme was used to select a statistically significant number of individuals for repeat DNA typing from each of these categories. The categories included antigens missed by serology, nonexpressed (null) alleles, PCR amplification failures, misassignment of antigens and nomenclature issues. Only a single individual was found to carry a null allele. DNA-based testing correctly typed nearly 99% of the donors at HLA-A, more than 98% at HLA-B, and more than 97% at both HLA-A and -B validating this methodology for registry typing.

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.

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.

Large-scale DNA-based typing of HLA-A and HLA-B at low resolution is highly accurate specific and reliable

DNA-based typing of HLA class I alleles of the HLA-A and HLA-B loci using sequence-specific oligonucleotide primers and/or probes has been used for the large-scale typing of individuals for the National Marrow Donor Program unrelated donor registry. Typing was performed by 16 laboratories at a low level of resolution (e.g. A*01, B*07). The results of blinded quality control analysis for the first 12 months of the project show the typing to be highly accurate, specific and reliable. The total error rate based on 11,545 HLA-A and 11,428 HLA-B assignments was 1.1% for HLA-A and 1.9% for HLA-B. This level of accuracy is particularly remarkable because the quality control samples could not be distinguished from 64,180 donor samples tested at the same time by the laboratories.

Monoclonal antibody specific to a subclass of polyproline-Arg motif provides evidence for the presence of an snRNA-free spliceosomal Sm protein complex in vivo: implications for molecular interactions involving proline-rich sequences of Sm B/B' proteins

The human spliceosomal Sm B/B' proteins are essential for the biogenesis of the snRNP particles. B/B' proteins contain several clusters of the PPPPGM/IR sequence, which occurs within the C-terminus of Sm B/B'. This sequence is very similar to the PPPPPGHR sequence of the cytoplasmic tail of the CD2 receptor and closely resembles the class II of SH3 ligands, suggesting a similarly important role. We report that a monoclonal antibody (3E10) against the PPPPPGHR sequence recognizes spliceosomal Sm B/B' proteins. Proteins that are specifically immunoprecipitated by 3E10 include Sm B, B', D1, D2, D3, E, F, and G. However, unlike Y12 and other anti-Sm immunoprecipitates, 3E10 immunoprecipitates appear to lack the U1 snRNP-specific proteins A and C and U snRNAs. These findings indicate that 3E10 recognizes a subset of Sm protein core and suggest the presence of snRNA-free Sm protein complex(es) in vivo. We propose that the epitope binding for 3E10 may become unaccessible upon interactions of Sm proteins and their subsequent incorporation into the core particles. The Sm proline-rich sequences may have an important role in mediating protein-protein interactions necessary for the proper snRNP core assembly or function, or both. To our knowledge, 3E10 is the first well characterized mAb specific for a subclass of polyproline-arg motif recognizing Sm B/B' and CD2 proteins. 3E10 antibody can be used to further characterize the nature of protein components in the snRNA-free Sm subcore protein complex(es) that are formed during the snRNP core assembly steps.

Cytotoxic T-cell clone against rectal carcinoma induced by stimulation of a patient's peripheral blood mononuclear cells with autologous cultured tumor cells

In an effort to establish cytolytic T lymphocytes (CTLs) against colorectal carcinoma (CRC) by stimulating patients' lymphocytes with autologous tumor cells, we used peripheral blood mononuclear cells (PBMC) from a patient with minimal residual rectal carcinoma following removal of the primary lesion and involved regional lymph nodes as a source to generate CTLs in culture. A CTL line and clone were established from the patient's PBMC following stimulation of PBMC with autologous, cultured tumor cells and interleukin-2. The CTL line and the clone consisted predominantly of CD4+ lymphocytes. The CTL clone expressed two T-cell receptor variable alpha chains (V alpha11 and V alpha22) and one beta chain (Vbeta14). The cytokine secretion pattern of the CTL line was of the Th1-type. Both the CTL line and the clone lysed the autologous rectal carcinoma cells, but not the allogeneic, partially human lymphocyte antigen (HLA)-matched or nonmatched CRC cells, autologous Epstein-Barr virus-transformed B cells, K562 (natural killer target) cells or Daudi (lymphokine-activated killer target) cells. Lysis of autologous tumor cells most likely was HLA class I-restricted. Our unique success in generating CTLs against this tumor type may rest in the inclusion of a patient with minimal residual, rather than advanced, disease.

Polymorphic nucleotides within the human IL-4 promoter that mediate overexpression of the gene

Atopy, which predisposes individuals to develop asthma, severe systemic anaphylaxis, and atopic dermatitis, is usually associated with dramatically elevated total serum IgE levels and is thought to be controlled by a major susceptibility gene and multiple minor susceptibility genes. A recent sib-pair analysis revealed a tight linkage between markers on 5q31.1 and a major susceptibility gene controlling total serum IgE levels. Due to its location within this cluster and its biologic role in Ig class switching and Th2 cell differentiation, the IL-4 gene has emerged as one major candidate for the atopy gene. In one model, polymorphisms within IL-4 regulatory elements might result in overexpression of the gene, amplifying Th2 cell differentiation and class switching to IgE. In support of this model, we report that the human IL-4 promoter exists in multiple allelic forms that exhibit distinct transcriptional activities in IL-4-positive T cells. A particular allele has an unusually high transcriptional activity. A nucleotide substitution within a recently described OAP40 element located just upstream of an NF-AT site (P sequence) appears to be largely responsible for the increased promotor strength of this particular allelic form of the IL-4 promoter. In EMSAs, this substitution results in a markedly enhanced affinity for sequence-specific complexes exhibiting an AP-1 specificity. The identification of allelic nucleotides, which results in overexpression of the IL-4 gene, provides specific targets for a comprehensive screening of atopic and nonatopic individuals and may provide a clue for genetic predisposition for atopy.

Polymorphic nucleotides within the human IL-4 promoter that mediate overexpression of the gene

Atopy, which predisposes individuals to develop asthma, severe systemic anaphylaxis, and atopic dermatitis, is usually associated with dramatically elevated total serum IgE levels and is thought to be controlled by a major susceptibility gene and multiple minor susceptibility genes. A recent sib-pair analysis revealed a tight linkage between markers on 5q31.1 and a major susceptibility gene controlling total serum IgE levels. Due to its location within this cluster and its biologic role in Ig class switching and Th2 cell differentiation, the IL-4 gene has emerged as one major candidate for the atopy gene. In one model, polymorphisms within IL-4 regulatory elements might result in overexpression of the gene, amplifying Th2 cell differentiation and class switching to IgE. In support of this model, we report that the human IL-4 promoter exists in multiple allelic forms that exhibit distinct transcriptional activities in IL-4-positive T cells. A particular allele has an unusually high transcriptional activity. A nucleotide substitution within a recently described OAP40 element located just upstream of an NF-AT site (P sequence) appears to be largely responsible for the increased promotor strength of this particular allelic form of the IL-4 promoter. In EMSAs, this substitution results in a markedly enhanced affinity for sequence-specific complexes exhibiting an AP-1 specificity. The identification of allelic nucleotides, which results in overexpression of the IL-4 gene, provides specific targets for a comprehensive screening of atopic and nonatopic individuals and may provide a clue for genetic predisposition for atopy.

Large-scale DRB and DQB1 oligonucleotide typing for the NMDP registry: progress report from year 2

DNA typing of HLA class II alleles of the DRB1/3/4/5 and DQB1 loci using sequence-specific oligonucleotide probes and polymerase chain reaction amplified DNA has been used for the large-scale typing of donors for the National Marrow Donor Program unrelated donor registry. The results of quality control analysis for the second year of the project (10/1/939/30/94) show the typing continues to be highly accurate, specific, and reliable. The average percent of correctly classified HLA oligotypes (groups of alleles defined by a hybridization pattern with a panel of sequence-specific oligonucleotide probes) based on 9,244 DRB1 and 7,244 DQB1 assignments was 99.8% (range 99.4%100.0%) for DRB1/DRB3/DRB4/DRB5 and 99.8% (range 99.6%100.0%) for DQB1. This level of accuracy is particularly remarkable because the 4,636 DRB quality control samples were tested blindly and could not be distinguished from 57,580 donor samples tested at the same time by the laboratories.

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.

V alpha gene usage in rheumatoid compared with osteoarthritic synovial tissue T cells

While many investigators have examined V gene usage by the clonotypic T-cell receptor (TCR) in rheumatoid arthritis (RA) joints, few have reported on arthritic controls. We compared TCR alpha-chain V gene usage in knee synovial tissue specimens from 9 RA and 5 osteoarthritis (OA) patients. There was no significant difference in the number of V gene families used in RA compared with OA synovium. However, there was an increased prevalence of V alpha 28, V alpha 10, V alpha 17, and V alpha 18 and under representation of V alpha 15 in RA compared with OA synovium. Of these, V alpha 28 was also recently described by us as being present in RA synovial tissue early in the course of disease. V alpha 28 associated J region usage, and N-regional diversity was surveyed in T-cell receptors from additional rheumatoid synovial tissue T-cell populations and normal peripheral blood. Oligoclonality was observed in 6/10 rheumatoid specimens either by direct sequencing or where three or more molecular clones were sequenced, compared with 0/5 normal PBMCs. The oligoclonal populations included 2/3 cell lines stimulated with interleukin-2 (IL-2) alone. Several novel J regions were observed, with some recurrent residues observed at N-region positions. These data indicate an increased prevalence of certain TCR V region families in RA versus OA synovium, and suggest an antigen-driven expansion of V alpha 28-expressing T cells in RA synovium.

Factors contributing to the development of burnout in oncology nursing

The purpose of this study was to determine whether oncology nurses experience higher levels of burnout compared to nurses working in general hospitals, and to further identify the personal and environmental factors that contribute to the development of emotional exhaustion, depersonalization and lack of personal accomplishment. Seven tools, measuring a selected set of demographic, psychological and occupational variables, were administered to 217 female nurses who worked in oncological hospitals and 226 nurses who worked in general hospitals in the area of Athens. Measures used in the study included the Maslach Burnout Inventory, the Hardiness Scale, the Ways of Coping Scale, the Life Style Scale, the Type A Behaviour Scale, a Job Stress Questionnaire and a General Information Questionnaire. No statistically significant difference was revealed in the degree of burnout experienced by nurses in oncology and those in general hospitals. Multiple linear regression analysis suggested that personality characteristics seem to predict a greater percentage of the variability of the burnout experienced than occupational and demographic variables. A sense of personal control over the things that happen in life and in the work environment was found to protect nurses from emotional exhaustion, depersonalization and lack of personal accomplishment.

Large-scale oligonucleotide typing for HLA-DRB1/3/4 and HLA-DQB1 is highly accurate, specific, and reliable

DNA typing of HLA class II alleles of the DRB1/3/4 and DQB1 loci using sequence-specific oligonucleotide probes and polymerase chain reaction-amplified DNA was used for the large-scale typing of donors for the National Marrow Donor Program unrelated donor registry. The results of quality control analysis for the first 7 months of the project show the typing to be highly accurate, specific, and reliable. The percent of correctly classified HLA oligotypes based on 1652 DRB1 and 1652 DQB1 assignments was greater than 99% for DRB1/DRB3/DRB4 and greater than 98% for DQB1. This level of accuracy is particularly remarkable because the quality control samples could not be distinguished from 9011 donor samples tested at the same time by the laboratories.

Induction of HLA class II molecules on human T cells: relationship to immunoregulation and the pathogenesis of AIDS

Human T cells express HLA class II molecules upon activation. The factors that regulate the induction of expression of these molecules are for the most part unknown. Here we report preliminary results indicating that tumor necrosis factor-alpha (TNF-alpha) regulates the induction of cell-surface HLA-DR, DO, and DP molecules in human T cells stimulated with PHA. In contrast, recombinant interferon-gamma (rIFN-gamma), recombinant interleukin-1 alpha (rIL-1 alpha), or rIL-4 appear to have no effect on class II expression. The role of class II molecules on activated T cells is discussed in relationship to immunoregulation and the progression of HIV infection. Three non-mutually exclusive hypotheses are discussed. In the first hypothesis, we consider the role of these class II molecules in antigen presentation of endogenously synthesized HIV envelope by CD4+ cells. The second is a clonal inactivation of virus-specific helper T cells that might occur as a consequence of a direct T cell to T cell interaction and a bypass of the "accessory signal" normally delivered by antigen-presenting cells such as macrophages. The third is a molecular mimicry between HIV envelope proteins and HLA class II molecules, which may lead to the development of autoimmunity against CD4+ T-cell-expressing class II molecules.

Glycogen regulation in LPS-stimulated murine splenocytes

Enzymatic glycogen regulation in mouse splenocytes cultured in vitro with and without LPS, was studied from 0-72 h. Increased [3H]glucose uptake and hexokinase activity demonstrated the activation of cells treated with LPS. There was a greater time-dependent increase of cellular glycogen content in LPS-stimulated cells as compared to control. Glycogen synthetase I in LPS-stimulated cells increased about 200% above control cells to a plateau at 48 h, while in unstimulated cells there was little increase throughout. Glycogen synthetase D increased continually to 72 h in both groups. In the stimulated cells, phosphorylase increased only 90% above control cells up to 48 h. It was concluded that the increased glycogen content of LPS-stimulated cells seen at 48 h may result from an increase in both glycogen synthetase I and D activity compared to lesser increase in hydrolysis. However, between 48 and 72 h, the period of RNA and DNA increased synthesis, the glycogen content of stimulated cells did not increase further, consistent with the observation that synthetase I activity remained constant and synthetase D decreased. Thus, following mitogenic stimulation, the net effect of the enzymatic regulation is to increase cellular glycogen, as an energy source for subsequent events.