Excess production of interleukin-12 subunit p40 stimulated by the virulence plasmid of Salmonella enterica serovar Typhimurium in the early phase of infection in the mouse.
The production of interleukin-12 (IL-12) and its subunits in response to Salmonella enterica serovar Typhimurium infection in the BALB/c mouse was examined. Unlike wild-type Typhimurium, a plasmidless strain, isolated by curing of the virulence plasmid (pSTV), did not stimulate excess IL-12p40 production. When a Tn 5 tagged pSTV was transferred back to the plasmidless strain, the ability to stimulate IL-12p40 production was restored. However, a strain harbouring another Tn50pSTV failed to stimulate excess IL-12p40 production. This Tn 5 insertion area, located on fragment H3 of pSTV, was designated spf (stimulation of protein forty). The ability to stimulate IL-12p40 production was restored in a partial diploid that carried a wild-type fragment covering the spf site. There is one known gene, repA, a locus, rsk, and two putative ORFs, in the vicinity of the Tn 5 insertion site; however, these are not spf. The precise location of the spf locus is still unknown.
Chang
Chien-Chung
CC
Chang Gung University College of Medicine, Department of Microbiology and Immunology, Kweishan, Taoyuan, 333 Taiwan, Taiwan.
Ou
Jonathan T
JT
D000818:Animals; D004251:DNA Transposable Elements / Q000235:genetics; D004171:Diploidy; D004797:Enzyme-Linked Immunosorbent Assay; D005260:Female; D006358:Hot Temperature; D018664:Interleukin-12 / Q000235:genetics / Q000378:metabolism*; D007700:Kinetics; D008070:Lipopolysaccharides / Q000494:pharmacology; D017737:Macrophages, Peritoneal / Q000276:immunology / Q000378:metabolism; D051379:Mice; D008807:Mice, Inbred BALB C; D016254:Mutagenesis, Insertional; D010957:Plasmids / Q000235:genetics*; D012333:RNA, Messenger / Q000378:metabolism; D012481:Salmonella Infections, Animal / Q000382:microbiology*; D012486:Salmonella typhimurium / Q000235:genetics / Q000276:immunology / Q000472:pathogenicity*; D017422:Sequence Analysis, DNA; D014774:Virulence / Q000235:genetics
D004251:DNA Transposable Elements; D008070:Lipopolysaccharides; D012333:RNA, Messenger; D018664:Interleukin-12