Sheep small intestinal mast cells/globule leucocytes: ability to divide.
The number of mucosal mast cells/globule leukocytes (MMC/GLs) increase in the intestinal mucosa in response to nematode parasite infections but it is not known if this accumulation is due to in situ cell division, derivation from elsewhere or some combination of both. To determine if MMC/GLs can divide, cells were obtained from immunized Romney sheep and cultured in vitro in RPMI 1640. For cultures supplemented with 10, 20 or 30% foetal lamb serum (FLS) or foetal calf serum (FCS) and without concanavalin A (Con A), cell division had ceased by day 2, but with Con A (3 micrograms ml-1) cell division continued to day 9. Better growth of cells was obtained with the higher concentrations of serum. However the use of 30% or 50% autologous serum with Con A lead to cell death but 10% serum permitted limited growth. The detrimental effect of autologous serum could be overcome by increasing the Con A concentration. It was established that an alpha-macroglobulin present in autologous serum can bind Con A. This macroglobulin appears to have a higher avidity for Con A than does the receptor(s) on the surface of MMC/GLs. Our data seem to indicate that a direct interaction of Con A with the cell surface or a receptor(s) is responsible for MMC/GLs division.
Stankiewicz
M
M
AgResearch, Wallaceville Animal Research Centre, Upper Hutt, New Zealand.
Jonas
W E
WE
Cabaj
W
W
Douch
P G
PG
D000818:Animals; D002455:Cell Division / Q000187:drug effects; D002478:Cells, Cultured; D003208:Concanavalin A / Q000494:pharmacology; D003470:Culture Media; D007106:Immune Sera / Q000502:physiology; D007413:Intestinal Mucosa / Q000166:cytology*; D007962:Leukocytes / Q000166:cytology*; D008407:Mast Cells / Q000166:cytology*; D012756:Sheep / Q000502:physiology*
D003470:Culture Media; D007106:Immune Sera; D003208:Concanavalin A