title: Crosstalk between alpha/beta T cells and gamma/delta T cells in vivo: activation of alpha/beta T-cell responses after gamma/delta T-cell modulation with the monoclonal antibody GL3.
abstract: Although gamma/delta T cells express numerous in vitro functions similar to alpha/beta T cells, little is known about their biological functioning in vivo. Furthermore, it is unclear whether alpha/beta T cells and gamma/delta T cells act independently or in a coordinated way. In the present study, gamma/delta T cells were modulated in vivo by i.p. injection of the anti-gamma/delta T-cell receptor (TCR) monoclonal antibody GL3. GL3 administration caused disappearance of the gamma/delta TCR in spleen and lymph node cells and the gamma/delta TCR was reexpressed after in vitro cultivation for a few days. When cultured in vitro for 4 days, in the absence of foreign antigens, spleen and lymph node alpha/beta T cells from GL3-modulated mice showed vigorous proliferative responses. CD4 T lymphocytes from GL3-modulated mice produced interleukin 2, and CD8 T cells developed into cytolytic T lymphocytes in vitro capable of lysing syngeneic and allogeneic targets. Treatment with heat-inactivated GL3 or with normal hamster immunoglobulin did not cause any of these effects. These findings suggest that the anti-gamma/delta TCR monoclonal antibody GL3 modulates gamma/delta T cells in vivo and that this modulation has profound effects on alpha/beta T-cell reactivity. Hence, the data suggest a role for gamma/delta T cells in the regulation of alpha/beta T-cell activation in vivo.
authors.affiliation: Department of Immunology, University of Ulm, Federal Republic of Germany.
authors.forename: S H
authors.initials: SH
authors.lastname: Kaufmann
authors.forename: C
authors.initials: C
authors.lastname: Blum
authors.forename: S
authors.initials: S
authors.lastname: Yamamoto
mesh_terms: D000818:Animals; D000911:Antibodies, Monoclonal / Q000276:immunology; D015496:CD4-Positive T-Lymphocytes / Q000276:immunology; D005260:Female; D007376:Interleukin-2 / Q000378:metabolism; D008213:Lymphocyte Activation; D008211:Lymphocyte Cooperation; D008297:Male; D051379:Mice; D008810:Mice, Inbred C57BL; D016693:Receptors, Antigen, T-Cell, alpha-beta / Q000502:physiology*; D016692:Receptors, Antigen, T-Cell, gamma-delta / Q000502:physiology*; D016176:T-Lymphocyte Subsets / Q000276:immunology*; D013602:T-Lymphocytes, Cytotoxic / Q000276:immunology
chemical_list: D000911:Antibodies, Monoclonal; D007376:Interleukin-2; D016693:Receptors, Antigen, T-Cell, alpha-beta; D016692:Receptors, Antigen, T-Cell, gamma-delta