title: Age-related changes in dermal mast cell prevalence in BALB/c mice: functional importance and correlation with dermal mast cell expression of Kit.
abstract: Differences in dermal mast cell prevalence for adult mice of different strains have been reported previously. In this study, the dermal mast cell prevalence for BALB/c and C57BL/6 mice at 6 weeks of age was similar but as BALB/c mice matured from 6 to 10 weeks of age, their dermal mast cell prevalence halved. In contrast, there was no significant difference in the dermal mast cell prevalence of 6- and 10-week-old C57BL/6 mice. These differences determined the degree of susceptibility of BALB/c and C57BL/6 mice of different ages to UVB (UV radiation of wavelength 280-320 nm)-induced systemic immunosuppression. Expression of the receptor for stem cell factor, Kit protein, was examined on mast cells under conditions in which the dermal mast cell prevalence varied. A significant correlation was observed between Kit expression by mast cells from adult BALB/c, DBA/2 and C57BL/6 mice and dermal mast cell prevalence. In BALB/c mice, mast cell Kit expression decreased as the mice matured from 6 to 10 weeks of age and correlated with the reduction in dermal mast cell numbers. Kit levels on dermal mast cells from C57BL/6 mice were consistently higher than on mast cells from BALB/c mice although significant reductions in Kit were also measured with ageing from 6 to 10 weeks. We hypothesize that regardless of the extent of Kit expression, the dermal mast cell populations were maximally expanded in C57BL/6 mice. We suggest that BALB/c mice of 6 and 10 weeks of age are useful hosts in which to quantitatively evaluate mast cell involvement in a range of functional assays involving skin.
authors.affiliation: Department of Microbiology & Infectious Diseases, School of Medicine, Flinders University of South Australia, Australia.
authors.forename: P H
authors.initials: PH
authors.lastname: Hart
authors.forename: M A
authors.initials: MA
authors.lastname: Grimbaldeston
authors.forename: E K
authors.initials: EK
authors.lastname: Hosszu
authors.forename: G J
authors.initials: GJ
authors.lastname: Swift
authors.forename: F P
authors.initials: FP
authors.lastname: Noonan
authors.forename: J J
authors.initials: JJ
authors.lastname: Finlay-Jones
mesh_terms: D000375:Aging / Q000235:genetics / Q000276:immunology*; D000704:Analysis of Variance; D000818:Animals; D002452:Cell Count; D020405:Dermis / Q000276:immunology* / Q000378:metabolism / Q000528:radiation effects; D005260:Female; D007091:Image Processing, Computer-Assisted; D007150:Immunohistochemistry; D007165:Immunosuppression Therapy; D008407:Mast Cells / Q000276:immunology* / Q000378:metabolism / Q000528:radiation effects; D051379:Mice; D008807:Mice, Inbred BALB C / Q000276:immunology*; D008810:Mice, Inbred C57BL; D008811:Mice, Inbred DBA; D019009:Proto-Oncogene Proteins c-kit / Q000378:metabolism*; D013045:Species Specificity; D014466:Ultraviolet Rays / Q000009:adverse effects
chemical_list: D019009:Proto-Oncogene Proteins c-kit