Effect of early weaning on the development of immune cells in the pig small intestine.
The controlled effects of age and weaning on the numbers of CD2+ T cells, subsets (CD4+, CD8+), accessory cells (macrophage/granulocyte) and cells expressing MHC class II (DQw) and IL-2R in the piglet intestine was investigated. At birth low numbers of CD2+CD4-CD8- cells were the only demonstrable T cells in the intestine. Monocyte/granulocyte and MHC class II+ cells were also detected in low numbers and IL-2R+ cells were proportionally quite numerous. All those cell populations, except the IL-2R+ cells, increased thereafter and peaked at Week 7 when the numbers of cells were comparable with those of adult animals. CD4+ cells increased dramatically after Week 1. In contrast, CD8+ remained scarce until after 5-7 weeks of age in unweaned animals. Four days after weaning at 3 weeks old, there were increases in CD2+ (P < 0.001) and macrophage/granulocyte (P < 0.01) cells in proximal small intestinal villi and in CD2+ cells only (P < 0.01) in crypts. No significant changes in cell numbers were demonstrated in the distal small intestine.
Vega-López
M A
MA
INIFAP-SARH, Mexico.
Bailey
M
M
Telemo
E
E
Stokes
C R
CR
D000375:Aging / Q000276:immunology; D000818:Animals; D016175:B-Lymphocyte Subsets / Q000276:immunology; D018801:CD2 Antigens / Q000032:analysis; D005260:Female; D006098:Granulocytes / Q000276:immunology; D000949:Histocompatibility Antigens Class II / Q000032:analysis; D007421:Intestine, Small / Q000166:cytology* / Q000276:immunology*; D008264:Macrophages / Q000276:immunology; D013552:Swine / Q000276:immunology*; D016176:T-Lymphocyte Subsets / Q000276:immunology; D014886:Weaning
D018801:CD2 Antigens; D000949:Histocompatibility Antigens Class II