Premium
Histidase function in human epidermal cells
Author(s) -
Barnhisel Mary L.,
Priest Robert E.,
Priest Jean H.
Publication year - 1970
Publication title -
journal of cellular physiology
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 1.529
H-Index - 174
eISSN - 1097-4652
pISSN - 0021-9541
DOI - 10.1002/jcp.1040760105
Subject(s) - foreskin , fibroblast , subculture (biology) , biology , tissue culture , cell culture , microbiology and biotechnology , in vitro , biochemistry , genetics
The activity of histidase was studied in (1) epidermal tissue scraped from human infant foreskin, (2) fibroblast‐like cells in monolayer serial culture from human foreskin, and (3) epithelial‐like (epidermal) outgrowth from foreskin primary explants. Foreskin epidermal tissue without in vitro culture and epidermal outgrowth in primary culture from explants of foreskin showed equivalent mean levels of histidase activity, 5.22 × 10 −3 and 5.01 × 10 −3 μMoles urocanic acid produced per milligram protein per minute. Under the same assay conditions, there was no measurable histidase activity in cultured fibroblast‐like cells from foreskin at various times after subculture. The K m for enzyme from human foreskin epidermal tissue ranged between 2 and 5 × 10 −3 M histidine. Ability to demonstrate the presence or absence of this tissue‐specific enzyme function in cultured cells suggests a useful means for studying differentiation, as well as a more precise way to identify epidermal origin of cultured cell types than morphological characteristics alone would permit.