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Enzyme-linked Immunospot Assay (ELISPOT): Quantification of Th-1 Cellular Immune Responses Against Microbial Antigens
Published on: November 23, 2010
Skin testing with recombinant Mycobacterium intracellulare antigens
S L Morris1, J C Mackall, A Malik
1Center for Biologics Evaluation and Research, Food and Drug Administration Bethesda, Maryland 20892.
Abstract:
The immunoreactivity of four recombinant Mycobacterium intracellulare beta-galactosidase fusion proteins, which correspond to 22, 40, 43 and 85 kDa M. intracellulare antigens, was assessed. Lymphoproliferative assays demonstrated that Escherichia coli lysates containing each of the fusion proteins stimulated T cells in vitro. Purified preparations of three of these recombinant M. intracellulare antigens (22, 43 and 85 kDa) also induced delayed-type hypersensitivity (DTH) reactions in sensitized guinea pigs. However, the skin test responses evoked by each of these antigens was not species-specific. Given these results, the potential utility as skin test reagents of the purified antigens or peptides derived from these proteins is discussed.

