Requirement of the conformational stability of a Salmonella ribosomal vaccine for its mouse protection.
The 43-kDa non-O antigenic component isolated from the crude ribosomal fraction of Salmonella typhimurium [9] was further purified by affinity chromatography (43-kDa protein: 43-kDp). Immunization with 43-kDp did not induce complete mouse protection in CF1 mice to 500 LD50 of S. typhimurium, although it elicited a substantial IgG antibody response. The 43-kDp exhibited the mitogenicity to splenocytes (CF1 and C3H/HeJ) and B cell-rich populations (CF1). Complexing 43-kDp with the compact ribosomes of Streptococcus pyogenes by formaldehyde (complex vaccine: CV) elicited both IgM and IgG antibodies to 43-kDp. CV induced a boosting effect to enhance IgG antibody response. Moreover, CV generated delayed-type hypersensitivity to salmonella antigens and also conferred complete protection against 500 LD50 challenge of S. typhimurium to CF1 mice. These abilities of CV were reduced or impaired by RNase digestion. CV was able to induce partial or complete protection in inbred mouse strains (C3H/HeN, C3H/HeJ, DBA/2 and A/J). These data, in addition to other reports, suggest that conformational stability between ribosomes and contaminating substances such as 43-kDp or O-antigens might be required for the overall effects of the ribosomal vaccine.
Department of Bacteriology, Nara Medical University, Kashihara City, Japan.
E
E
Kita
D
D
Oku
F
F
Nishikawa
M
M
Emoto
K
K
Yasui
S
S
Kashiba
D000818:Animals; D001428:Bacterial Vaccines / Q000276:immunology*; D005260:Female; D007114:Immunization; D008213:Lymphocyte Activation; D051379:Mice; D008815:Mice, Inbred Strains; D011487:Protein Conformation; D012260:Ribonucleases / Q000494:pharmacology; D012270:Ribosomes / Q000276:immunology*; D012486:Salmonella typhimurium / Q000276:immunology*
D001428:Bacterial Vaccines; D012260:Ribonucleases