Activation and detection of HTLV-I Tax-specific CTLs by epitope expressing single-chain trimers of MHC class I in a rat model.
BACKGROUND
Human T cell leukemia virus type I (HTLV-I) causes adult T-cell leukemia (ATL) in infected individuals after a long incubation period. Immunological studies have suggested that insufficient host T cell response to HTLV-I is a potential risk factor for ATL. To understand the relationship between host T cell response and HTLV-I pathogenesis in a rat model system, we have developed an activation and detection system of HTLV-I Tax-specific cytotoxic T lymphocytes (CTLs) by Epitope expressing Single-Chain Trimers (SCTs) of MHC class I.


RESULTS
We have established expression vectors which encode SCTs of rat MHC-I (RT1.Al) with Tax180-188 peptide. Human cell lines transfected with the established expression vectors were able to induce IFN-gamma and TNF-alpha production by a Tax180-188-specific CTL line, 4O1/C8. We have further fused the C-terminus of SCTs to EGFP and established cells expressing SCT-EGFP fusion protein on the surface. By co-cultivating the cells with 4O1/C8, we have confirmed that the epitope-specific CTLs acquired SCT-EGFP fusion proteins and that these EGFP-possessed CTLs were detectable by flow cytometric analysis.


CONCLUSIONS
We have generated a SCT of rat MHC-I linked to Tax epitope peptide, which can be applicable for the induction of Tax-specific CTLs in rat model systems of HTLV-I infection. We have also established a detection system of Tax-specific CTLs by using cells expressing SCTs fused with EGFP. These systems will be useful tools in understanding the role of HTLV-I specific CTLs in HTLV-I pathogenesis.
Division of Molecular Virology, Institute for Genetic Medicine, Hokkaido University, Sapporo, Japan. ohashi-t@igm.hokudai.ac.jp
Takashi
T
Ohashi
Mika
M
Nagai
Hiroyuki
H
Okada
Ryo
R
Takayanagi
Hisatoshi
H
Shida
D000595:Amino Acid Sequence; D000818:Animals; D002460:Cell Line; D002478:Cells, Cultured; D016207:Cytokines / Q000235:genetics / Q000276:immunology; D004195:Disease Models, Animal; D018984:Epitopes, T-Lymphocyte / Q000235:genetics* / Q000276:immunology; D005260:Female; D015870:Gene Expression; D016356:Gene Products, tax / Q000235:genetics* / Q000276:immunology; D005805:Genes, MHC Class I; D005822:Genetic Vectors / Q000235:genetics; D015490:HTLV-I Infections / Q000276:immunology* / Q000821:virology; D015368:Human T-lymphotropic virus 1 / Q000235:genetics* / Q000276:immunology; D006801:Humans; D015459:Leukemia-Lymphoma, Adult T-Cell / Q000276:immunology / Q000821:virology; D008969:Molecular Sequence Data; D051381:Rats; D011916:Rats, Inbred F344; D011993:Recombinant Fusion Proteins / Q000235:genetics / Q000276:immunology; D013602:T-Lymphocytes, Cytotoxic / Q000276:immunology* / Q000821:virology; D015533:Transcriptional Activation
D016207:Cytokines; D018984:Epitopes, T-Lymphocyte; D016356:Gene Products, tax; D011993:Recombinant Fusion Proteins; C514970:tax protein, Human T-lymphotrophic virus 1