Genetic studies of the murine corneal response to Pseudomonas aeruginosa

The murine genetic control of resistance to Pseudomonas aeruginosa eye infection previously has been demonstrated to be regulated by two complementing dominant genes, PsCR1 and PsCR2. The PsCR1 locus apparently is not associated with the H-2 complex, whereas the PsCR2 locus could not definitively be associated with H-2. In this study we attempted to demonstrate a possible H-2 linkage of the PsCR2 locus. A panel of inbred congenic strains varying with either the H-2 haplotype or genetic background from inbred partners of C57BL/10, C3H, A, and BALB/c strains were characterized for their P. aeruginosa infectivity phenotypes. These studies indicated that the PsCR2 locus is not associated with the H-2 locus. Furthermore, variations of the H-2 haplotype did not change the resistance patterns observed in these strains. However, BALB.B and BALB.K congenic lines were resistant to P. aeruginosa eye infection, whereas BALB/cJ mice were susceptible. Examination of hybrids (BALB.K X BALB/cJ)F1 and (BALB.B X BALB/cJ)F1 demonstrated that an autosomal dominant gene(s), PsCR, confers resistance. Segregation analysis for the H-2 haplotype and the PsCR gene in offspring of backcross matings with the BALB/cJ parental strain suggested that this PsCR gene is not linked to the H-2 complex and has an inheritance pattern of a single locus or several tightly linked loci.