Abstract
T-cell responses were studied in mice immunized with the Salmonella typhimurium aroA SL3261 live attenuated vaccine strain. T-cell responses in the spleen, both in whole cell populations and in nylon wool non-adherent (T-cell enriched) cells, were studied in vitro as proliferation by incorporation of tritiated thymidine and production of T-cell specific cytokines [IL-2 (interleukin-2)/IL-4]. Stimulating antigens included whole Salmonella lysates and purified lipopolysaccharide (LPS), both untreated and after alkaline hydrolysis to prevent the nonspecific mitogenic effect of LPS. Strong proliferative responses were obtained with untreated whole cell extract and LPS, which were decreased by polymyxin B (PB). Alkaline detoxification of the antigens decreased the proliferative response of nylon-wool non-adherent populations to LPS, but greatly increased their response to the Salmonella extract. Surprisingly, PB also reduced proliferation to detoxified LPS. Little or no IL-2/IL-4 production was seen in response to LPS or purified polysaccharide antigens, while there was a strong IL-2/IL-4 response to whole cell lysate, again markedly increasing after alkaline treatment. The results suggest that the T-cell response elicited by immunization with live Salmonella aroA vaccines in mice recognizes antigens other than LPS determinants, and that estimation of T-cell responses to Salmonella antigens by proliferation alone may yield misleading results.
Original language | English |
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Pages (from-to) | 305-315 |
Number of pages | 11 |
Journal | Microbial Pathogenesis |
Volume | 13 |
Issue number | 4 |
DOIs | |
Publication status | Published - 01 Oct 1992 |
Keywords
- immunity
- infection
- mice
- Salmonella
- T cells
- vaccine
- Vaccination
- Polymyxin B/pharmacology
- Lipopolysaccharides/antagonists & inhibitors
- Female
- Lymphocyte Activation/drug effects
- 3-Phosphoshikimate 1-Carboxyvinyltransferase
- Bacterial Vaccines/immunology
- T-Lymphocytes/immunology
- Vaccines, Attenuated/immunology
- Salmonella typhimurium/genetics
- Interleukin-2/biosynthesis
- Spleen/immunology
- Interleukin-4/biosynthesis
- Animals
- Bacterial Proteins/genetics
- Alkyl and Aryl Transferases
- Immunologic Memory
- Mice
- Mice, Inbred BALB C
- Sodium Hydroxide/pharmacology