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Objective To construct and screen the human immunodeficiency virus-1 (HIV-1) negative regulation factor (Nef) peptide-specific CD4+ T lymphocyte clone.Methods Peripheral blood mononuclear cells (PBMC) from five asymptomatic HIV-1 infected patients were collected and Bulkcultured with Nef end peptides.The CD4 molecule and intracellular interferon (IFN)-gamma of cultured cells were detected by two-color flow cytometry.The Nef end peptide-specific T cell clone was then constructed by limited dilution and confirmed through enzyme linked immunospot assay (ELISPOT).The best grown cells were selected and cultured as the final clone.Results The Nef end peptide-specific-T lymphocyte clone was successfully constructed from PBMC of one HIV-infected patient and confirmed by ELISPOT.The detection of human leukocyte antigen (HLA)-DRB1 type showed that the epitope of this peptide was probably HLA-DRB1 * 0406.Conclusion The Nef end specific-T cell clone is successfully constructed,and a new epitope in the C-terminus of Nef protein and its HLA restriction are identified.
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BACKGROUND: We analyzed T cell receptor beta chain (TCRB) gene to investigate the presence of putative T cell clones and its clinicopathologic implications in Korean patients with aplastic anemia (AA). METHODS: Twenty-nine bone marrow specimens were collected from 20 AA patients, 19 specimens from initial diagnosis and 10 from follow-up. T cell clonality assay was performed using IdentiClone(TM) TCRB Gene Clonality Assay kit (InVivoScirbe Technology, USA) and automatic genetic analyzer. Patients' clinical information and laboratory parameters were also analyzed. RESULTS: Five patients had definitive underlying factors related with aplastic anemia, such as hepatitis B virus (4 cases) and benzene exposure (1 case). Putative T cell clones were detected in bone marrow specimens of 11 (58%) out of 19 patients at diagnosis. The location of putative T cell clones of TCRB gene (diversity region, Dbeta; joining region, Jbeta; variable region, Vbeta) was distributed in Dbeta2+Jbeta2 (6 cases), Dbeta1+Jbeta1 (3 cases), Vbeta+Jbeta1 (2 cases), and Dbeta1+Jbeta2 (2 cases). Interestingly, among seven patients who underwent stem cell transplantation, five patients with no T cell clones detected at diagnosis developed new T cell clones during the follow-up. CONCLUSIONS: Putative pathogenetic T cell clones were detected in most of AA patients in the current study. T cell clonality assay would be useful for investigating the pathophysiology of acquired AA.