title: [Study on the TCR Vbeta binding sites in the superantigen staphylococcal enterotoxin D].
abstract: OBJECTIVE
  To study TCR Vbeta binding sites of staphylococcal enterotoxin D(SED).
  
  
  METHODS
  Six SED mutants were constructed by site-directed mutagenesis. The activity of promoting T cell proliferation by the mutants was detected by (3)H-TdR incorporation. For the mutants with decreased mitogenic activity, flow cytometry was used detect their MHC-II binding activity and TCR Vbeta specificity.
  
  
  RESULTS
  Residue N23 played an important role in the interaction of SED with human TCR Vbeta5. Residue H26 was probably a SED binding site to human TCR Vbetas except for TCR Vbeta5, TCR Vbeta8 and TCR Vbeta12.1.
  
  
  CONCLUSIONS
  Residue N23 is a key TCR Vbeta binding site of SED.
authors.affiliation: Department of Epidemiology, Third Military Medical University, Chongqing 400038, China. yafeilye@yahoo.com.cn
authors.forename: Ya-fei
authors.initials: YF
authors.lastname: Li
authors.forename: Li
authors.initials: L
authors.lastname: Zhong
authors.forename: Xi-hua
authors.initials: XH
authors.lastname: Zhu
authors.forename: Xi-hua
authors.initials: XH
authors.lastname: Zhu
authors.forename: Jin
authors.initials: J
authors.lastname: Yang
mesh_terms: D001665:Binding Sites; D001667:Binding, Competitive; D045744:Cell Line, Tumor; D049109:Cell Proliferation; D004768:Enterotoxins / Q000235:genetics / Q000276:immunology / Q000378:metabolism*; D005802:Genes, MHC Class II; D006801:Humans; D016393:Lymphoma, B-Cell / Q000473:pathology; D009154:Mutation; D016693:Receptors, Antigen, T-Cell, alpha-beta / Q000378:metabolism*; D013211:Staphylococcus aureus / Q000276:immunology*; D018089:Superantigens / Q000235:genetics / Q000276:immunology / Q000378:metabolism*; D013601:T-Lymphocytes / Q000166:cytology*
chemical_list: D004768:Enterotoxins; D016693:Receptors, Antigen, T-Cell, alpha-beta; D018089:Superantigens; C019368:enterotoxin D, Staphylococcal