Antigen processing (TAP, HLA-DM and LMP) genes map within the major histocompatibility complex (MHC) class II region between the HLA-DQB1 and -DPB1 loci, and are involved in the processing of peptides bound to HLA class I or class II molecules. In order to determine the allele frequencies of antigen processing genes and the various linkage disequilibria existing among these genes, we have analyzed TAP1, TAP2, HLA-DMA, and HLA-DMB, LMP2, LMP7 polymorphisms in 184 unrelated healthy Koreans using the rnethod of PCR-SSCP, ARMS-PCR and PCR-RFLP. The frequencies of antigen processing genes were TAP1A (77.7%), TAP1*B (17.1%), TAP1*C (5.2%), TAP2*A (41.6%), TAP2*B (31.3%), TAP2*C (3.3%), TAP2*D (0.8%), TAP2*E (6.5%), TAP2*G (0.8%), HLA-DMA*0101 (81.5%), HLA-DMA*0102 (18.2%), HLA-DMA*0103 (0.3%), HLA-DMB*0101 (42.9%), HLA-DMB*0102 (19.0%), HLA-DMB*0103 (38.0%), LMP2*R (78.8%), LMP2*H (21.2%), LMP7*A (35.3%), LMP7*B (56.0%), LMP7*C (4.9%), and LMP7*D (3.8%). We also analysed two- locus association among each locus. Many significant positive associations were observed between these two loci, such as between HLA-DMB and TAP1, between HLA-DMA and HLA-DMB, between LMP2 and LMP7, and between TAP1 and LMP7. Conversely, any significant linkage disequilibrium was not detected between HLA-DMB and LMP2. These results could be used as control data for disease association and population genetics studies in Korean population.
Antigen Presentation* ; Gene Frequency ; Genetics, Population ; Linkage Disequilibrium ; Major Histocompatibility Complex ; Peptides

No abstract available.
Humans ; Leukocytes*

No abstract available.
Alleles* ; Gene Frequency* ; HLA-DR Antigens* ; Polymerase Chain Reaction*

No abstract available.
DNA* ; Humans* ; Polymerase Chain Reaction*

No abstract available.
Humans* ; Retroviridae*

No abstract available.
DNA Fingerprinting* ; DNA* ; Oligonucleotide Probes* ; Polymerase Chain Reaction*

Epstein-Barr virus (EBV) is a potent inducer of polyclonal B lymphocyte proliferation and a tool for the establishment of human B lymphoblastoid cell lines (B-LCLs), which have proven useful for several human immunologic applications. B-LCLs serve as efficient antibody-producing cells and antigen-presenting cells. In spite of these advantages, the cloning efficiency of B-LCLs is less than 1%. In order to generate clones of B-LCLs, we cultured B-LCLs with and without canine stromal cell line, DO64, as feeder cell which was immortalized by transduction of retrovirus encoding E6 and E7 of the human papilloma virus type 16 (HPV-16), which was defined to produce various cytokines including stem cell factor (SCF) and interleukin- 6 (IL-6). After 3 weeks of B-LCLs cultured with DO64, 8.3% and 37.5% in 1 cell and 3 cells per well were efficiently cloned, respectively. There was no significant effect on growing of 8-LCLs without DO64 cells and on high concentration of FBS. The cloning efficiency of B-LCLs transduced by retrovirus cultured with and without DO64 cells was 4.2% and 0% in 3 cells per well, respectively, while that of stable transfectant 33.3% and 8.3% in 1 cell per well, respectively. Our results suggest that the use of DO64 cells as feeder cells might permit the cloning of B-LCLs. This efficient cloning of B-LCLs could be used for the convenient source of autologous antigen-presenting cells expressing foreign antigen for the study of human immune responses in vitro, and for a variety of additional purposes, such as the production of human monoclonal antibodies.
Antibodies, Monoclonal ; Antibody-Producing Cells ; Antigen-Presenting Cells ; Cell Line* ; Clone Cells* ; Cloning, Organism* ; Cytokines ; Feeder Cells* ; Herpesvirus 4, Human ; Humans* ; Lymphocytes ; Papilloma ; Retroviridae ; Stem Cell Factor ; Stromal Cells*

Purpose : The main genetic contribution to type 1 diabetes susceptibility is the human leukocyte antigen (HLA) class II gene. Several non-HLA chromosomal regions are also known to be involved. We studied the association of HLA class II and non-HLA candidate genes, which are cytotoxic T lymphocyte antigen-4 (CTLA4), tumor necrosis factor (TNF), lymphotoxin-alpha(LT-alpha, and vitamin D receptor (VDR) gene, polymorphisms with disease susceptibility in Korean children with type 1 diabetes.Methods : Fifty Korean children with type 1 diabetes (29 girls and 21 boys) and 166 healthy Koreans were investigated in this study. HLA class II alleles were determined by PCR-SSP (sequence-specific primer) and PCR-SSOP (sequence specific oliogonucleotide probe) method. CTLA4 exon 1 polymor phism was analyzed by PCR-SSCP (single strand conformation polymorphism), and TNF promotor and LT-alphagene polymorphism by PCR-RFLP (restriction fragment length polymorphism), respectively. VDR gene polymorphisms were analyzed by PCR-RFLP using restriction enzyme FokI, ApaI, TaqI, and BsmI. Results : The frequencies of HLA-DRB1*04, DRB1*09, and DQB1*04 were significantly increased and those of HLA-DRB1*14, DRB1*15, DQB1*05 and DQB1*06 were significantly decreased in the patients with type 1 diabetes compared with the control subjects. No significant differences in the distribution of CTLA4 exon 1, TNF promotor, LT-alpha and VDR gene polymorphisms were observed between the patients with type 1 diabetes and the control subjects. Conclusion : These data suggest that HLA-DRB1*04, DRB1*09, and DQB1*04 are susceptible genes for type 1 diabetes, whereas HLA-DRB1*14, DRB1*15, DQB1*05, and DQB1*06 are protective genes in Korean children. CTLA4 exon 1, TNF promotor, LT-alpha and VDR gene polymorphisms are not associated with susceptibility to type 1 diabetes in Korean children.
Alleles ; Child* ; Diabetes Mellitus, Type 1* ; Disease Susceptibility* ; Exons ; Female ; Genes, MHC Class II ; Humans ; Leukocytes ; Lymphocytes ; Receptors, Calcitriol ; Tumor Necrosis Factor-alpha

A defective HIV-1 helper virus DNA, pHyPC, was assembled by deleting the RNA packaging signal, env, nef and the 3'LTR sequences. HIV-1 like virus particles that carry the HIV-1 receptor, CD4 were generated by coexpression of pHyPC and plasmid DNAs encoding different chimeric CD4 proteins. The CD4 particles, sharing the CD4 ectodomain, precisely fused to different membrane anchors. CD4(+) particles specifically bound to HIV-1 Env expressing cells, but any signs of infection into these cells were not detected. Binding was only partially blocked by either polyclonal anti-CD4 antibodies or by high concentrations of soluble CD4. Suprisingly, CD4(+) particles also adsorbed to HeLa, CHO, NIH3T3 and COS-7 cells in the absence of HIV-1 Env expression. Adsorption was comparable in strength and speed to the highly specific CD4-Env interaction. CD4(-) particles exhibited only background levels of binding. Cell binding was CD4- dependent, but it was independent of the cell type from which the CD4(+) particles originated. Interestingly, CD4-dependent/Env-independent binding was only found when CD4 was present on virus particles. This suggests that the micro-environment of CD4 on virus particles uniquely expose this new cell binding activity. Its high affinity could explain in part why infection of Env(+) cells by CD4(+) particles was not detected. Further experiments will be required to evlauate whether this strong membrane interaction could represent one step in the multiple-step viral entry process.
Adsorption ; Animals ; Antibodies ; COS Cells ; DNA ; Helper Viruses ; HIV-1* ; Membranes ; Plasmids ; Product Packaging ; RNA ; Virion

No abstract available.
HLA-A2 Antigen* ; Isoelectric Focusing*