PMID- 1940373
OWN - NLM
STAT- MEDLINE
DCOM- 19911218
LR  - 20141120
IS  - 0022-1767 (Print)
IS  - 0022-1767 (Linking)
VI  - 147
IP  - 11
DP  - 1991 Dec 1
TI  - Staphylococcal toxins bind to different sites on HLA-DR.
PG  - 3876-81
AB  - Staphylococcal enterotoxins (SE) and toxic shock syndrome toxin 1 (TSST-1) bind 
      to MHC class II molecules and the toxin-class II complexes induce proliferation 
      of T cells bearing specific V beta sequences. We have previously reported that 
      these toxins display varying binding affinities for HLA-DR1. We now investigated 
      whether these differences simply reflected differences in binding affinity for a 
      single class II binding site or, at least in part, the engagement of different 
      binding sites on the HLA-DR complex. Through competitive binding studies we show 
      that SEB and TSST-1, which are not closely related by their amino acid sequences, 
      bind to two different sites on HLA-DR. Both of these sites are also occupied by 
      staphylococcal enterotoxin A (SEA), enterotoxin D (SED), and enterotoxin E (SEE) 
      which exhibit more than 70% amino acid sequence homology. SEB and TSST-1 failed 
      to inhibit SEA binding to HLA-DR. These studies suggest that there may be three 
      distinct, although perhaps overlapping, binding sites on HLA-DR for these toxins. 
      Further, although SED and SEE are similar to SEA in structure, and appear to bind 
      the same sites on HLA-DR as SEA, they displayed significantly lower binding 
      affinities. T cell proliferative responses to SED required a higher concentration 
      of the toxin than SEA, probably reflecting its lower binding affinity. SEE, 
      however, elicited T cell responses at very low concentrations, similar to SEA, 
      despite its much lower binding affinity. Therefore, although the affinities of 
      these toxins to MHC class II molecules appear to significantly influence the T 
      cell responses, the effective recognition of the toxin-class II complex by the 
      TCR may also contribute to such responses.
FAU - Chintagumpala, M M
AU  - Chintagumpala MM
AD  - Howard Hughes Medical Institute Laboratory, Baylor College of Medicine, Houston, 
      TX 77030-3498.
FAU - Mollick, J A
AU  - Mollick JA
FAU - Rich, R R
AU  - Rich RR
LA  - eng
GR  - AI15394/AI/NIAID NIH HHS/United States
GR  - AI21289/AI/NIAID NIH HHS/United States
GR  - AI30036/AI/NIAID NIH HHS/United States
PT  - Journal Article
PT  - Research Support, U.S. Gov't, P.H.S.
PL  - United States
TA  - J Immunol
JT  - Journal of immunology (Baltimore, Md. : 1950)
JID - 2985117R
RN  - 0 (Bacterial Toxins)
RN  - 0 (Enterotoxins)
RN  - 0 (HLA-DR Antigens)
RN  - 0 (Superantigens)
RN  - 0 (enterotoxin F, Staphylococcal)
SB  - IM
MH  - Bacterial Toxins/*metabolism
MH  - Binding Sites
MH  - Binding, Competitive
MH  - Enterotoxins/*metabolism
MH  - HLA-DR Antigens/*metabolism
MH  - Humans
MH  - In Vitro Techniques
MH  - Lymphocyte Activation
MH  - Protein Binding
MH  - Staphylococcus aureus/*pathogenicity
MH  - *Superantigens
EDAT- 1991/12/01 00:00
MHDA- 1991/12/01 00:01
CRDT- 1991/12/01 00:00
PHST- 1991/12/01 00:00 [pubmed]
PHST- 1991/12/01 00:01 [medline]
PHST- 1991/12/01 00:00 [entrez]
PST - ppublish
SO  - J Immunol. 1991 Dec 1;147(11):3876-81.