Combined Studies of Complement Receptor and Surface Immunoglobulin-Bearing Cells and Sheep Erythrocyte Rosette-Forming Cells in Normal and Leukemic Human Lymphocytes

Abstract

A B S T R A C T Human lymphocytes from normal peripheral blood, thymus, spleen, thoracic duct, and peripheral lymphocytes from patients with chronic lymphatic leukemia were studied for complement receptor sites (CRL), surface immunoglobulin (SIg), and for the ability to form rosettes with sheep erythrocytes (TRFC). The two B cell markers (CRL and SIg) were found to be in overlapping, but not totally identical populations, whereas cells that were able to form rosettes were found in a totally unrelated population of lymphocytes; TRFC is therefore probably a reliable marker for T cells. In peripheral blood 24% of lymphocytes had SIg, but only half of these were also CRL. Almost all of the non-SIg peripheral blood lymphocytes were TRFC. In the spleen and thoracic duct only a few lymphocytes were observed that had SIg and were not CRL. On the other hand, in two of three spleens studied 10-20% of cells were CRL that did not have SIg. In the thoracic duct all non-CRL, non-SIg cells were TRFC. In chronic lymphatic leukemia three findings were made: (a) The presence or absence of CRL was independent of the presence or absence of SIg so that in individuals whose cells were non-SIg, CRL were usually plentiful.

Ontogeny of B Lymphocytes

“…There is ample evidence in mice that a substantial portion (up to 40 %) of Ig-bearing lymphocytes in spleen and lymph node lack detectable C receptors (24,25) and, as shown here, these cells appear before cells which bear C receptors. In human peripheral blood, it has also been reported that a substantial fraction of Ig + cells lack the C receptor (26), although the frequency of CRL does depend on (27). Thus, an Ig + CR-lymphocyte is well established, as of course is the Ig + CR + lymphocyte.…”

Binding of Soluble Immune Complexes to Human Lymphoblastoid Cells

“…In several reports on the classification of peripheral human lymphocytes as T and B cells, it has been stated that the percentage of' B cells having MBIg was higher than that of B cells having C3b receptors (24,30,31). In those studies, C3b receptors were demonstrated by the rosette technique.…”

“…On the other hand, cultured cells may have lost surface receptors which were present on the cells from which they were derived. For example, it has been shown that three subclasses of B-type lymphocytes are present in the blood of patients with chronic lymphocytic leukemia; cells having only MBIg, cells having only receptors for C3 and cells having both MBIg and receptors for C3 (24). In addition, in patients with X-linked agammaglobulinemia, lymphocytes without MBIg but with receptors for C3 have been described (25).…”

RECEPTORS FOR AGGREGATED IgG ON MOUSE LYMPHOCYTES

“…It is difficult to assess which of these several differences between laboratories may account for the higher degree of B-cell specificity of the agg IgG receptor in the Bentwich et al study (2-4 % of T cells, as measured by their capacity to form rosettes with sheep erythrocytes, also bound agg-IgG) and the lack of such specificity in our study. The possibility that in peripheral blood the agg IgG receptor is primarily associated with B cells, whereas in the spleen it is not, is considered a real one since in a previous study on the occurrence of surface immunoglobulin and complement receptors (25), it was found that whereas in peripheral blood the complement receptor was found almost exclusively on SIg + cells, in the spleen there was a significant population of cells that were SIg-complement receptor positive.…”