Immunoglobulin determinants on lymphocytes in germ‐free piglets

Abstract

Surface IgM determinants on splenic lymphocytes were detected in 80-day old pig fetuses using anti-L and anti-p sera conjugated with horseradish peroxidase. Similarly, by the immunofluorsecence technique, only IgM determinants were demonstrated o n unprimed lymphocytes from spleen and bone marrow iin fetuses at the end of gestation (on the 112-1 14th day) and in precolostral, germ-free piglets.The pattern of labeling with anti-p sera is characteristic for nonactivated lymphocytes as documented on fetal splenic lymphocytes o r the small lymphocytes in a dense lymphatic area of the omentum of precolostral piglets. The lymphocytes which showed surface immunofluorescence staining with anti-y serum were observed in conventionally reared, nonimmunized piglets and appeared in all the germ-free reared piglets which were immunized with sheep red blood cells, human serum albumin or bacterial antigens.We conclude that the true antigen recognition units, or "primary" receptors, on antigen-sensitive uncomitted lymphocytes are exclusively of the IgM type and that the IgG-carrying cells can be detected in piglets only after antigenic stimulation.

Variability of the immunological state of germfree colostrum-deprived Minnesota miniature piglets

“…Sow serum (S) was diluted 1:8; all piglet sera were diluted 1:4. (3,5,6,8,14,16) by different investigators may be due to the variability of the functional placental barriers of the different swine in different environments. Thus, the most important basic requirement for obtaining immunologically "virgin" piglets is healthy, specific pathogen-free pregnant sows with intact placental barriers.…”

Surface Markers of Porcine Lymphocytes and Distribution in Various Lymphoid Organs

“…Moreover, the number of EA-RFC was twofold higher than that of ZC-RFC in spleen, mesenteric lymph node and cisterna chyli. This latter organ was the only one without null cell.The existence of porcine lymphocytes with SIg [2,4,15,16,[32][33][34], receptors for sheep erythrocytes (ED) in presence of dextran [6,29], activated complement compo nents [25,28,32] and for the bound immu noglobulin (FcIC) [5] has already been de scribed. Until now, no data are available about the Fc receptor for aggregated IgG (Fc-agg) or cold cytophilic Ig on pig lym phocytes.…”