|
|
||||||||
The Journal of Immunology, Vol 147, Issue 10 3274-3281, Copyright © 1991 by American Association of Immunologists
ARTICLES |
D Grossman, M Van, JA Mollick, SK Highlander and RR Rich
Department of Microbiology, Baylor College of Medicine, Houston, TX 77030.
The hallmark of T cell responses to staphylococcal enterotoxins (SE) and other super-Ag is a selective stimulation of cells expressing particular TCR-V beta segments. Our previous studies suggested that the disulfide loop in SE is critical for their interaction with the TCR. To investigate this concept in further detail we constructed disulfide loop mutants of staphylococcal enterotoxin A (SEA), and examined these altered toxins for mitogenicity, class II MHC binding, and V beta specificity. We found that substitutions of either Cys-96 or Cys-106 decreased mitogenicity by 100-fold without significantly affecting class II binding or resistance of the molecule to proteolysis. Several mutants lost the capacity to stimulate V beta 11+ cells, except a Cys- 106----Gln mutant for which V beta 11-stimulatory activity was increased. By contrast, mutants containing Cys----Ala substitutions acquired the capacity to stimulate V beta 6+ cells. Despite these effects of V beta specificity, all mutants retained the predominant preference of SEA for V beta 3+ cells. Neither exchange of regions flanking the loop in SEA with corresponding residues in SEB, nor conversion of the entire loop region of SEA to that of SEE, were associated with transfers of V beta specificity. Our results suggest that the disulfide loop in SEA contributes to toxin avidity for the TCR, rather than specificity for particular V beta.
This article has been cited by other articles:
![]() |
K. Petersson, H. Pettersson, N. J. Skartved, B. Walse, and G. Forsberg Staphylococcal Enterotoxin H Induces V{alpha}-Specific Expansion of T Cells J. Immunol., April 15, 2003; 170(8): 4148 - 4154. [Abstract] [Full Text] [PDF] |
||||
![]() |
J. Yamaoka, E. Nakamura, Y. Takeda, S. Imamura, and N. Minato Mutational Analysis of Superantigen Activity Responsible for the Induction of Skin Erythema by Streptococcal Pyrogenic Exotoxin C Infect. Immun., October 1, 1998; 66(10): 5020 - 5026. [Abstract] [Full Text] [PDF] |
||||
| HOME | HELP | FEEDBACK | SUBSCRIPTIONS | ARCHIVE | SEARCH | TABLE OF CONTENTS |