CD4+T-cells activation

CTL induction experiments consistently demonstrate that IRIV indeed enhance induction of HLA class I-restricted CTL specific for IMsg-ee and Melan-A/Mart-127-35 epitopes. CTL induction in presence of irradiated or nonirradiated CD4+ cells showed that IRIV CTL adjuvance requires CD4+ T-cell activation. Remarkably, IRIV CTL adjuvance observed in our in vitro studies is solely due to IRIV immunogenicity and independent of peptide delivery and protection capacities, as peptides were not encapsulated in nor attached to IRIV. Further studies are warranted to clarify whether and to what extent delivery, protection, and immunogenic capacities of IRIV synergize in CTL adjuvance. The fact that IRIV adjuvance was observed in relation to the tumor-associated epitope Melan-A/Mart-127-35 encourages further evaluation of IRIV as potential adjuvants in cancer... 

Schumacher R, Adamina A, Zurbriggen R, et al. Influenza virosomes enhance class I restricted CTL induction through CD4+ T cell activation. Vaccine 2004 22 714. 

The mechanism whereby one subset is activated in preference to the other is not completely understood but appears to involve IL-4 and IFN7 (Fig. 3.8 Swain, 1991 Swain et al., 1991 Chatelain etal., 1992). In mice, IL-4 supports the generation ofTH2 cells (Swain etal., 1990) and suppresses ThI cell development, while IFN7 suppresses the development of Th2 cells (Gajewski et al., 1989a). TGF)3 induces a cell population distinct from ThI and Th2 which predominantly secretes IL-2 and expresses a memory phenotype (Swain et al., 1991). CD4 T cells, activated in the presence of IL-6, are reported to have a ThO cytokine profile (Croft and Swain, 1991). Similar effects of IL-4 and IFN7 are seen in the rat... 

Griffin JM, Gilbert KM, Lamps LW, Pumford NR (2000a) CD4(+) T-cell activation and induction of autoimmune hepatitis following trichloroethylene treatment in MRL +/+ mice. Toxicol Sci, 57 345-352. 

IL-21 CD4 T cells Activates antigen-specific CD8 T cells and NKT cells Increases the production of IgG by mature B cells... 

Hogaboam CM, NW Lukacs, SW Chensue, RM Strieter, SL Kunkel. 1998. Monocyte chemoattractant protein-1 synthesis by murine lung fibroblasts modulates CD4 T cell activation. J Immunol 160 4606. 

Anguita J, Ramamoorthi N, Hovius JW et aL Salpl5, an Ixodes scapularis salivary protein, inhibits CD4 T-cell activation. Immunity 2002 16(6) 849-859. 

Brinckerhoff CE, Coffey JW, SuUivan AC. 1983. Inflammation and collagenase prodnction in rats with adjuvant arthritis reduced with 13-cis-retinoic acid. Science 221 756-758. Campbell DJ, Butcher EC. 2002. Rapid acquisition of tissue-specific homing phenotypes by CD4+ T cells activated in cutaneous or mucosal lymphoid tissues. J. Exp. Med. 195 135-141. 

Wolday D, Akuffo H, Demissie A, Britton S (1999) Role of Leishmania donovani and Its Lipophosphoglycan in CD4(+) T-cell Activation-Induced Human Immunodeficiency Virus Replication. Infect Immun 67(10) 5258-5264. 

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