PMID- 1281444
OWN - NLM
STAT- MEDLINE
DCOM- 19930119
LR  - 20190720
IS  - 0008-4166 (Print)
IS  - 0008-4166 (Linking)
VI  - 38
IP  - 9
DP  - 1992 Sep
TI  - Receptors for toxic shock syndrome toxin-1 and staphylococcal enterotoxin A on 
      human blood monocytes.
PG  - 937-44
AB  - Staphylococcal toxic shock syndrome toxin-1 (TSST-1) as well as staphylococcal 
      enterotoxin A (SEA) and B (SEB) have recently been shown to bind directly to the 
      class II major histocompatibility antigen, HLA-DR. Whereas others have 
      characterized TSST-1 and SEA binding to HLA-DR on transfected L cells or B 
      lymphoma cell lines, we sought evidence for direct binding of TSST-1 and SEA to 
      HLA-DR on purified human monocytes. A single class of high-affinity receptors was 
      found for both TSST-1 (dissociation constant (Kd) 40 nM, 3.4 x 10(4) receptors 
      per cell) and SEA (Kd 12 nM, 3.2 x 10(4) receptors per cell) on normal human 
      monocytes. Affinity cross-linking of 125I-labeled toxins to monocytes revealed 
      the presence of two membrane protein subunits with molecular masses consistent 
      with the alpha and beta chains of human HLA-DR (35 and 28 kDa, respectively). The 
      anti-HLA-DR monoclonal antibody L243, but not L203 or 2.06, inhibited 
      radiolabeled toxin binding to human monocytes and neutralized the mitogenic 
      response of human T lymphocytes to both toxins. However, L243 was consistently 
      more effective in blocking radiolabeled TSST-1 than SEA binding to human 
      monocytes from the same donors, suggesting that TSST-1 and SEA may be binding to 
      overlapping epitopes rather than to the same epitope on HLA-DR. Because TSST-1 
      and SEB bind to distinct epitopes on HLA-DR and because SEA cross competes with 
      both TSST-1 and SEB on the HLA-DR receptor, we postulate that SEA occupies a 
      binding site within HLA-DR that overlaps both TSST-1 and SEB.(ABSTRACT TRUNCATED 
      AT 250 WORDS)
FAU - See, R H
AU  - See RH
AD  - Department of Medicine, University of British Columbia, Vancouver, Canada.
FAU - Krystal, G
AU  - Krystal G
FAU - Chow, A W
AU  - Chow AW
LA  - eng
PT  - Journal Article
PT  - Research Support, Non-U.S. Gov't
PL  - Canada
TA  - Can J Microbiol
JT  - Canadian journal of microbiology
JID - 0372707
RN  - 0 (Bacterial Toxins)
RN  - 0 (Enterotoxins)
RN  - 0 (Epitopes)
RN  - 0 (HLA-DR Antigens)
RN  - 0 (Receptors, Cell Surface)
RN  - 0 (Receptors, Peptide)
RN  - 0 (Superantigens)
RN  - 0 (enterotoxin F, Staphylococcal)
RN  - 37337-57-8 (enterotoxin A, Staphylococcal)
RN  - EC 4.6.1.2 (Guanylate Cyclase)
RN  - EC 4.6.1.2 (Receptors, Enterotoxin)
RN  - EC 4.6.1.2 (Receptors, Guanylate Cyclase-Coupled)
SB  - IM
MH  - Adult
MH  - *Bacterial Toxins
MH  - Electrophoresis, Polyacrylamide Gel
MH  - Enterotoxins/immunology/*metabolism
MH  - Epitopes
MH  - *Guanylate Cyclase
MH  - HLA-DR Antigens/immunology/metabolism
MH  - Humans
MH  - Monocytes/*metabolism
MH  - Receptors, Cell Surface/immunology/*metabolism
MH  - Receptors, Enterotoxin
MH  - Receptors, Guanylate Cyclase-Coupled
MH  - *Receptors, Peptide
MH  - Staphylococcus aureus/immunology/*metabolism
MH  - *Superantigens
EDAT- 1992/09/01 00:00
MHDA- 1992/09/01 00:01
CRDT- 1992/09/01 00:00
PHST- 1992/09/01 00:00 [pubmed]
PHST- 1992/09/01 00:01 [medline]
PHST- 1992/09/01 00:00 [entrez]
AID - 10.1139/m92-151 [doi]
PST - ppublish
SO  - Can J Microbiol. 1992 Sep;38(9):937-44. doi: 10.1139/m92-151.