Recombinant Staphylococcal Enterotoxin Type A Stimulate Antitumoral Cytokines

Abstract

Background:About 20 different types of staphylococcal enterotoxins are produced by Staphylococcus aureus, in which type A is more common in food poisoning syndrome. Also staphylococcal enterotoxin A superantigen is a potent inducer of cytotoxic T lymphocyte activity and cytokine production and could stimulate T cells containing T-cell receptor beta chain domains when binding to major histocompatibility complex class II molecules. Hence, it is an important reagent in cancer immunotherapy.Methods:For the construction of pET-21a/entA cassette, the staphylococcal enterotoxin type A gene was isolated from S aureus strain HN2, cloned into pET-21a, and introduced into Escherichia coli strain BL-21(DE3). Consequently, Western blot analysis showed pET-21a/entA cassette expression inserted entA gene successfully. It is the first prompt using a pET-21a as a cloning vector for entA gene and expression of construct in BL-21(DE3). In addition, this study examined the ability of standard staphylococcal enterotoxin A and cloned staphylococcal enterotoxin A to activate T cells in vitro. Lymphocyte cells derived from lymph node BALB/c mice were exposed to standard staphylococcal enterotoxin A and cloned staphylococcal enterotoxin (1.10, 102,103, and 104 ng/µL) in order to evaluate the magnitude of proliferation, activation, and apoptosis of lymphocyte cells based on MTT and apoptosis assays, respectively.Results:Our investigation showed that the function of cloned staphylococcal enterotoxin A was same as standard staphylococcal enterotoxin A, and the optimal concentration for the activation of lymphocyte cells and induction of apoptosis was 100 ng/µL and 1000 ng/µL (P < .05), respectively. Quantification of cytokines clearly showed that lymphocyte cells exposed to standard staphylococcal enterotoxin A and cloned staphylococcal enterotoxin A significantly secreted higher interferon γ and tumor necrosis factor α compared to control.Conclusion:According to our results, the biological activity of standard staphylococcal enterotoxin A and cloned staphylococcal enterotoxin A is identical; therefore, these procedures may be approved as an efficient method to express and purify this protein in a large scale.

IL-33 and Superantigenic Activation of Human Lung Mast Cells Induce the Release of Angiogenic and Lymphangiogenic Factors

“…In particular, protein L binds with high-affinity only human VkI, VkIII and VkIV subtypes, but does not interact with VkII subtype [ 49 ]. Several allergic [ 50 , 51 , 52 , 53 , 54 , 55 ] and autoimmune disorders [ 56 , 57 ], neoplasia [ 58 , 59 , 60 ], and immunodeficiencies [ 44 ] can be associated with SAgs.…”

Construction, Expression, and Characterization of rSEA-EGF and In Vitro Evaluation of its Antitumor Activity Against Nasopharyngeal Cancer

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Machine Learning for Prediction of Drug Targets in Microbe Associated Cardiovascular Diseases by Incorporating Host‐pathogen Interaction Network Parameters

“…CCP1 of S. cerevisiae degrades reactive oxygen species within the mitochondria and is involved in conveying an oxidative stress signal [67] . Staphylococcal EntA superantigen is a potent inducer of cytotoxic T lymphocyte activity and cytokine production and could stimulate T‐cell receptor ß chain domains when binding to major histocompatibility complex class II (MHC II) molecules [68] expressed by endothelial cells and promotes infective endocarditis [69] . A number of candidate T cell stimulating epitopes have been identified within the AAV capsid protein VP1, which may be attractive targets as they induce the cell‐mediated immune responses [70] .…”