Bacterial superantigens induce rapid and T cell receptor V beta-selective down-regulation of L-selectin (gp90Mel-14) in vivo.
Upon challenge of mice with bacterial superantigens such as staphylococcal enterotoxin B, several facets of TCR V beta-selective acute T-cell alterations can be observed, which include acute T cell priming, and systemic lymphokine release followed by ligand-specific unresponsiveness. Prompted by experiments showing that stimulation of T cells by phorbol esters in vitro results in rapid shedding of the L-selectin homing receptor, we investigated the expression of adhesion molecules on superantigen-responsive T cells in vivo. Here we show that bacterial superantigens cause TCR V beta-specific loss of L-selectin. Down-regulation of L-selectin was selective, since the expression of other lymphocyte surface receptors was not changed. L-Selectin down-regulation represents a superantigen-induced immediate cell surface alteration and was not observed on T cells stimulated by TCR-specific antibodies. Loss of expression was almost complete within 30 min, and recovered 50 h after challenge. The results suggest that acute loss of L-selectin is a hallmark of T cell activation by bacterial superantigens that may result in profound changes of T lymphocyte recirculation pathways.
Miethke
T
T
Institute of Medical Microbiology and Hygiene, Technical University of München, Germany.
Wahl
C
C
Holzmann
B
B
Heeg
K
K
Wagner
H
H
D000818:Animals; D000911:Antibodies, Monoclonal / Q000494:pharmacology; D015815:Cell Adhesion Molecules / Q000378:metabolism*; D015536:Down-Regulation; D004768:Enterotoxins / Q000276:immunology; D005260:Female; D007700:Kinetics; D019041:L-Selectin; D008213:Lymphocyte Activation; D008297:Male; D051379:Mice; D008807:Mice, Inbred BALB C; D016693:Receptors, Antigen, T-Cell, alpha-beta / Q000378:metabolism*; D016201:Receptors, Lymphocyte Homing / Q000378:metabolism; D018089:Superantigens; D013601:T-Lymphocytes / Q000276:immunology* / Q000378:metabolism
D000911:Antibodies, Monoclonal; D015815:Cell Adhesion Molecules; D004768:Enterotoxins; D016693:Receptors, Antigen, T-Cell, alpha-beta; D016201:Receptors, Lymphocyte Homing; D018089:Superantigens; D019041:L-Selectin; C031818:enterotoxin B, staphylococcal