Differences in cell division and thymidine incorporation with rat and primate fibroblasts in collagen lattices.
Human and gorilla dermal fibroblasts, primate cells, suspended in a collagen lattice, do not divide for the first 3 days. In contrast, rat fibroblasts divide within 24 hr. In this study, the proliferation of rat fibroblasts were compared to primate fibroblasts. Rat fibroblasts in monolayer culture increase from 100,000 to 355,000 in 2 days, and human cells increase from 100,000 to 436,000 in the same period. An initial seeding of 100,000 rat fibroblasts suspended in collagen increased to 163,000 cells in 2 days. An initial 100,000 human fibroblasts seeded in collagen decreased to 80,000 cells in 2 days. Retarded proliferation of human and gorilla fibroblasts in collagen is unrelated to a defect in DNA synthesis. By autoradiography human fibroblasts suspended in collagen incorporate labelled thymidine. By flow cytometry analysis, the DNA concentrations of human fibroblasts suspended in collagen exhibited 41% in a 4N chromosome state, compared to 14% in monolayer culture. Nuclei of gorilla fibroblasts from collagen displayed 42% in a 4N state, compared to 19% in monolayer culture. With nuclei of rat fibroblasts from collagen, 14% were in a 4N state, compared to 9% in monolayer culture. Primate fibroblasts show a three-fold increase in the number of nuclei in a 4N state compared to rat fibroblasts suspended in collagen. After replating fibroblasts released from collagen in monolayer culture in the presence of 1 mM hydroxyurea (an inhibitor of DNA synthesis) primate fibroblasts doubled in 24 hr. Under identical conditions, rat fibroblasts showed no cell division.(ABSTRACT TRUNCATED AT 250 WORDS)
Greco
R M
RM
Department of Pathology, Shriners Burns Institute, Boston, MA.
Ehrlich
H P
HP
D000818:Animals; D002455:Cell Division / Q000502:physiology; D002460:Cell Line; D003094:Collagen; D005347:Fibroblasts / Q000166:cytology* / Q000378:metabolism; D005434:Flow Cytometry; D006071:Gorilla gorilla; D006801:Humans; D008297:Male; D051381:Rats; D017207:Rats, Sprague-Dawley; D013936:Thymidine / Q000378:metabolism*
D003094:Collagen; D013936:Thymidine