OBJECTIVE To investigate the effects of recombinant staphylococcal enterotoxin A (rSEA) and its mutant proteins on lymphocyte proliferation, activation and lymphocyte subsets. METHODS The human peripheral blood mononuclear cells (PBMC) were isolated from human peripheral blood and splenocytes cells were isolated from mouse. MTT colorimetry was established to determine the lymphocyte proliferation in human PBMC and mouse splenocytes cells stimulated by rSEA and its mutant proteins in vitro. The percents of lymphocyte subsets (CD3+, CD4+, CD8+T cell) and activation CD4+, CD8+T cell and nature killer cells (NK) in PBMC were analyzed by FCM. RESULTS 5-20 mg·L-1 rSEA and its mutant proteins showed the significant effects on promoting proliferation of human PBMC and mouse splenocytes (P<0.05). The percents of CD3+, CD4+ and CD8+ T cells in PBMC treated with rSEA and rSEA/H225A were significantly higher than those of the control group.The rSEA/H187A mutant proteins increased the percents of CD3+ and CD8+ T cells, while the rSEA/D227A mutant proteins only increased the percents of CD8+ T cells(P<0.05). The percents of activation CD4+ and CD8+ T cells were increased by rSEA and its mutant proteins, as the percents of NK cells were increased by rSEA, rSEA/H187A and rSEA/H225A mutant proteins(P<0.05). CONCLUSION The significant effects on promoting lymphocyte proliferation and activation of rSEA, rSEA/H187A, rSEA/H225A and rSEA/D227A were confirmed. The percents of lymphocyte subsets and NKC were increased in different degrees by rSEA and its mutant proteins, which establishing the foundation for further screening of low toxicity and more efficient agent mutants.
Key words
KEY WORDS: staphylococcal enterotoxin A /
recombinant mutant protein /
lymphocyte proliferation /
lymphocyte subsets
{{custom_keyword}} /
{{custom_sec.title}}
{{custom_sec.title}}
{{custom_sec.content}}
References
[1] TORRES B A, KOMINSKY S, PERRIN G Q, et al. Superantigens: the good, The bad, and the ugly[J]. Exp Biol Med, 2001, 226 (3): 164-176.
[2] HERMANN C, AULOCK S, GRAF K, et al. A model of human whole blood lymphokine release for in vitro and ex vivo use[J]. J Immunol Methods, 2003, 275 (1): 69-79.
[3] DOHLSTEN M, KALLAND T, GNNARSSON P, et al. Man-made superantigens: Tumor-selective agents for T-cell-based therapy[J]. Adv Drug Deliv Rev, 1998, 31(1): 131-142.
[4] XU S L, MAO Y F, ZHANG M G, et al. Construction and identification of prokaryotic expression system of staphylococcal enterotoxin A gene and expressed product[J]. Chin J Pathophysiol(中国病理生理杂志), 2007, 23(1): 163-167.
[5] LITTON M J, DOHLSTEN M, HANSSON J, et al. Tumor therapy with antibody-targeted superantigen generates a dichotomy between local and systemic immune response[J]. Am J Pathol, 1997, 150(5): 1607-1618.
[6] FONTENRAN J F, LARSSON M, SOMERSAN S, et al. Generation of high quantities of viral and tumor-specific human CD4+ and CD8+ T cell clones using peptide pulsed dendritic cells[J]. J Immunol Methods, 2001, 258 (1): 111-126.
[7] SMART J M, KEMP A S. Increased Th1 and Th2 allergen-induced cytokine responses in children with atopic disease[J]. Clin Exp Allergy, 2002, 32(5): 796-802.
[8] DOHLSTEN M, ABRAHMSEN L, BJORK P, et al. Monoclonal antibody-superantigen fusion proteins: Tumor-specific agents for T-cell-based tumor therapy[J]. Proc Natl Acad Sci USA, 1994, 91(19): 8945-8949.
[9] BORST D W, BETLEY M J. Mutations in the promoter spacer region and early transcribed region increase expression of staphylococcal enterotoxin A[J]. Infect Immun, 1993, 61(12): 5421-5425.
[10] HANSSON J, OHLSSON L, PERSSON R, et al. Enetically engineered superantigens as tolerable antitumor agents[J]. Proc Narl Acad Sci, 1997, 94 (6): 2489-2494.
[11] ABRAHMSEN I, DOHLSTEN M, SEGREN S, et al. Characterization of two distinct MHC class II binding sites in the superantigen staphylococcal enterotoxin A[J]. EMBO J, 1995, 14(13): 2978-2986.
{{custom_fnGroup.title_en}}
Footnotes
{{custom_fn.content}}