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Biomedical subjects

T Kobata

Publications and source records attributed to T Kobata.

76 records · Page 5Linked to original sources
PubMed1990

[Induction and functional analysis of gamma delta TCR-bearing T cells from human tonsil by Streptococcus pyogenes stimulation].

The killer cell characteristics of gamma delta TCR-bearing T cells induced from human tonsil by streptococcus pyogenes stimulation were examined. Immunohistologic staining of tonsil showed that gamma delta TCR-bearing T cells were mainly located in the interfollicular area connected with stratified squamous epithelium. Streptococcus pyogenes could induce the proliferation of gamma delta TCR-bearing T cells from tonsil in the presence of low-dose of IL-2. This streptococcus pyogenes-induced gamma delta TCR-bearing T cell proliferation was likely to be independent on the IL-2/IL-2R system since an obvious inhibition was not observed with anti-IL-2 and anti-IL-2R mAbs. More importantly, these gamma delta TCR-bearing T cells exhibited cell-mediated cytotoxic activity in a 4 hr 51 Cr-release assay. In addition, immunocytochemical staining revealed that these cells contained a killer protein perforin. These results demonstrate that gamma delta TCR-bearing T cells from tonsil exhibit typical killer cell characteristics. These data also suggest that gamma delta TCR-bearing T cells in human tonsil may play a cytotoxic role in protecting the integrity of tonsil from infection.

Cytotoxicity, Immunologic↗
PubMed1989

Molecular cloning and chromosomal assignment of a human perforin (PFP) gene.

Human perforin cDNA was isolated and the complete nucleotide sequence of the gene determined. The deduced amino acid sequence of human perforin showed 68.4% similarity to that of mouse perforin. RNA blot analysis of the human perforin gene revealed that the gene product is expressed preferentially in killer-type cells among cell lines tested, and in large granular lymphocytes among the peripheral blood mononuclear cells. In situ hybridization analysis with a human perforin cDNA probe revealed that the human perforin (PFP) gene is located on chromosome 17q11-21.

Base Sequence↗
PubMed1987

[On the mechanisms of human T cell proliferation induced by the 10B4 molecule].

The 10B4 system of human T cells seems to constitute a member of T cell receptor complex. We have analyzed the mechanisms by which a monoclonal antibody against the 10B4 molecule activates human peripheral T cells. The 10B4 antibody together with goat anti-mouse immunoglobulin antibody induced significant increase of DNA and RNA syntheses in T cells with peak responses on day 9 and on day 7, respectively. This activation process is mediated by interleukin 2 (IL-2) and its receptor (IL-2R), because (1) IL-2 activity was detected in the culture supernatants, (2) the percentage of IL-2R positive cells increased during the culture period, with a peak on day 9, and (3) the 10B4-induced T cell proliferation was inhibited by anti IL-2R antibody. Blocking studies with pharmacological agents showed that in the 10B4-induced system, a protein kinase C (PK-C) inhibitor, palmitoylcarnitine, blocked DNA synthesis, RNA synthesis, IL-2 production and IL-2R expression whereas a Ca ion channel blocker, verapamil, inhibited DNA synthesis, RNA synthesis, IL-2 production but not IL-2R expression. It is thus concluded that PK-C activation is required for IL-2 production and IL-2R expression and that channel-mediated Ca ion influx is important for IL-2 production but may not be needed for IL-2R expression.

Animals↗