With the intention of using the pig as a large animal model in haematopoiet
ic research, a clonal assay in methylcellulose was developed and the optima
l conditions for raising erythroid progenitors from adult pig bone marrow (
BM) and peripheral blood (PB) have been established. Progenitor cells were
stimulated to proliferate and differentiate in vitro by growth factors cont
aining leucocyte condition medium (LCM), and with recombinant human erythro
poietin (rhEpo). The number of PB BFU-E (burst forming units - erythroid) d
irectly depended on the concentration of LCM, but BM BFU-E were not depende
nt on LCM. Both CFU-E (colony forming units - erythroid) and BFU-E were rhE
po, dependent. Despite relatively high but expected individual variations,
the mean number of colonies, as well as the functional characteristics of p
rogenitor cells investigated, were similar to those of miniature pigs and s
ome other mammals. (C) 1999 Harcourt Publishers Ltd.