Essential roles of perforin in antigen-specific cytotoxicity mediated by human CD4+ T lymphocytes: analysis using the combination of hereditary perforin-deficient effector cells and Fas-deficient target cells.
Although the cytotoxic mechanisms of murine CTLs have been investigated extensively using various mutant and knockout mice, those of human CTLs, especially CD4+ CTLs, are still obscure. To clarify the roles of perforin in Ag-specific cytotoxicity mediated by human CD4+ CTLs, alloantigen-specific and HSV-specific human CD4+ T lymphocyte bulk lines and clones were established from a patient with hereditary perforin deficiency and her healthy father, and their cytotoxic activities were investigated. Alloantigen-specific CD4+ T lymphocytes expressing perforin exerted cytotoxicity against Fas-negative as well as Fas-positive allogeneic B lymphoblastoid cell lines established from members of a family with hereditary Fas deficiency. Perforin-deficient, but not perforin-expressing, CD4+ T lymphocytes failed to show strong cytotoxicity against HSV-infected autologous B lymphoblastoid cells. Perforin-deficient CD4+ T lymphocytes could exert relatively low level cytotoxicity against allogeneic IFN-gamma-treated keratinocytes. Although cytotoxicity mediated by perforin-expressing CD4+ CTLs was almost completely inhibited by concanamycin A, a potent inhibitor of the perforin-mediated cytotoxic pathway, cytotoxicity against IFN-gamma-treated keratinocytes mediated by perforin-deficient CD4+ T lymphocytes was inhibited only partially by concanamycin A, but was inhibited significantly by antagonistic anti-Fas Ab and anti-Fas ligand Ab. The combination of perforin-deficient effector T lymphocytes and Fas-negative target cells used in the present study provides a novel experimental system for studying the detailed mechanisms of human CTL-mediated cytotoxicity. The present data demonstrate that perforin-negative CD4+ CTLs can exert cytotoxicity against Fas-sensitive target cells; however, perforin plays essential roles in Ag-specific cytotoxicity mediated by human CD4+ as well as CD8+ CTLs.
Yanai
Fumio
F
Department of Pediatrics, Fukuoka University School of Medicine, Fukuoka, Japan.
Ishii
Eiichi
E
Kojima
Kensuke
K
Hasegawa
Atsuhiko
A
Azuma
Taichi
T
Hirose
Shinichi
S
Suga
Naohiro
N
Mitsudome
Akihisa
A
Zaitsu
Masafumi
M
Ishida
Yasushi
Y
Shirakata
Yuji
Y
Sayama
Koji
K
Hashimoto
Koji
K
Yasukawa
Masaki
M
D001402:B-Lymphocytes / Q000276:immunology; D018414:CD8-Positive T-Lymphocytes / Q000276:immunology* / Q000378:metabolism; D002461:Cell Line, Transformed; D002478:Cells, Cultured; D002999:Clone Cells; D018920:Coculture Techniques; D003601:Cytotoxicity Tests, Immunologic; D003602:Cytotoxicity, Immunologic / Q000235:genetics* / Q000276:immunology; D018984:Epitopes, T-Lymphocyte / Q000276:immunology*; D005260:Female; D015616:Histiocytosis, Non-Langerhans-Cell / Q000235:genetics / Q000276:immunology; D006650:Histocompatibility Testing; D006801:Humans; D007223:Infant; D007371:Interferon-gamma / Q000096:biosynthesis; D007519:Isoantigens / Q000276:immunology; D015603:Keratinocytes / Q000276:immunology; D008213:Lymphocyte Activation / Q000235:genetics; D008297:Male; D008562:Membrane Glycoproteins / Q000096:biosynthesis / Q000172:deficiency* / Q000235:genetics / Q000502:physiology*; D009154:Mutation / Q000276:immunology; D054353:Perforin; D052899:Pore Forming Cytotoxic Proteins; D018139:Simplexvirus / Q000276:immunology; D016176:T-Lymphocyte Subsets / Q000276:immunology* / Q000378:metabolism; D050378:T-Lymphocytes, Regulatory / Q000276:immunology* / Q000378:metabolism; D019014:fas Receptor / Q000235:genetics* / Q000502:physiology
D018984:Epitopes, T-Lymphocyte; D007519:Isoantigens; D008562:Membrane Glycoproteins; D052899:Pore Forming Cytotoxic Proteins; D019014:fas Receptor; D054353:Perforin; D007371:Interferon-gamma