A novel adjuvant, a mixture of alum and the general opioid antagonist naloxone, elicits both humoral and cellular immune responses for heat-killed Salmonella typhimurium vaccine.
In the current study, we tested the efficacy of the mixture of naloxone, an opioid receptor antagonist, and alum, as a new adjuvant, in the induction of humoral and cellular immunity in response to heat-killed Salmonella typhimurium (HKST) as a model vaccine. BALB/c mice were divided into five groups. Mice in the experimental groups received either the HKST vaccine alone or in combination with the adjuvant alum, naloxone or the alum-naloxone mixture. Mice in the negative control group received phosphate-buffered saline. All mice were immunized two times on days 0 and 14. Two weeks after the last immunization, immune responses to S. typhimurium were assessed. Our results indicated that the administration of the alum-naloxone mixture as an adjuvant increased the ability of the HKST vaccine to enhance lymphocyte proliferation, shifted the immune response towards a T-helper 1 (Th1) pattern and increased S. typhimurium-specific immunoglobulin G (IgG), IgG2a, IgG1 and the ratio of IgG2a to IgG1. This resulted in improved protective immunity against S. typhimurium. In conclusion, the administration of the alum-naloxone mixture as an adjuvant, in combination with the HKST vaccine, can enhance both humoral and cellular immunity and shift the immune responses to a Th1 pattern.
Department of Microbiology, Immunology and Genetics, Faculty of Medicine, Urmia University of Medical Sciences, Urmia, Iran.
Nima Hosseini
NH
Jazani
Mohammad
M
Sohrabpour
Ebrahim
E
Mazloomi
Shahram
S
Shahabi
D000276:Adjuvants, Immunologic / Q000494:pharmacology*; D000534:Alum Compounds / Q000494:pharmacology*; D000818:Animals; D000907:Antibodies, Bacterial / Q000097:blood; D049109:Cell Proliferation; D016207:Cytokines / Q000276:immunology; D007111:Immunity, Cellular / Q000187:drug effects*; D056724:Immunity, Humoral / Q000187:drug effects*; D007074:Immunoglobulin G / Q000276:immunology; D008099:Liver / Q000382:microbiology; D008214:Lymphocytes / Q000166:cytology / Q000187:drug effects; D008297:Male; D051379:Mice; D008807:Mice, Inbred BALB C; D009270:Naloxone / Q000494:pharmacology*; D012480:Salmonella Infections / Q000517:prevention & control; D022562:Salmonella Vaccines / Q000276:immunology*; D012486:Salmonella typhimurium / Q000276:immunology; D013154:Spleen / Q000382:microbiology; D016019:Survival Analysis; D015164:Vaccines, Inactivated / Q000276:immunology
D000276:Adjuvants, Immunologic; D000534:Alum Compounds; D000907:Antibodies, Bacterial; D016207:Cytokines; D007074:Immunoglobulin G; D022562:Salmonella Vaccines; D015164:Vaccines, Inactivated; D009270:Naloxone