Isolation and functional characterization of human intestinal mucosal lymphoid cells.

TLDR

Viable suspensions of human colonic mucosal lymphoid cells were prepared by sequential treatment with dithiothreitol, EDTA in calcium‑ and magnesium‑free salt solutions, and purified collagenase. Intestinal lymphocytes displayed a more mature/activated phenotype than peripheral blood cells, with higher IgA⁺ bone marrow‑derived cells, spontaneous macrophage association, rapid rosette formation, increased Ig synthesis, larger and more active macrophage/monocytes, and reduced null, IgD, IgM cells and PHA responsiveness, suggesting the preparation is suitable for studying IBD, GI cancer, and intestinal immunity.

Abstract

Viable suspensions of human colonic mucosal lymphoid cells have been prepared by sequential treatment of tissue with dithiothreitol, EDTA in calcium- and magnesium-free salt solutions, and purified collagenase. The intestinal lymphocyte population, in comparison with that of peripheral blood, had greater numbers of bone marrow-derived cells, particularly cells bearing membrane IgA; showed spontaneous association with macrophages; underwent rapid rosette formation with sheep erythrocytes; and demonstrated increased in vitro synthesis of immunoglobulin. Total thymus-derived cells were equal in the two populations. Decreases were found in "null" cell numbers, in cells bearing membrane IgD and IgM, and in responsiveness to phytohemagglutinin. Macrophage/monocytes in the intestinal population were increased in size, granularity, motility, sustained glass adherence, and phagocytic activity. Human intestinal lymphoid cells appear to constitute a cell population that is more "mature" and/or "activated", in comparison with the lymphoid cells of peripheral blood. The method of preparation should lend itself to the study of inflammatory bowel disease, gastrointestinal cancer, and the intestinal secretory immune system.