Ia‐Expressing Cells and T Lymphocytes of Different Subsets in Peripheral Nerve Tissue during Experimental Allergic Neuritis in Lewis Rats

Abstract

Inflammatory infiltrates in sciatic nerves during the acute phase of experimental allergic neuritis in the Lewis rat were characterized with regard to occurrence and distribution of Ia-expressing cells and T lymphocyte subsets by an immunohistochemical double-staining technique, enabling the simultaneous visualization of T lymphocytes and Ia-expressing non-T cells. Large numbers of Ia-expressing irregular macrophage-like/dendritic cells were seen both within inflammatory infiltrates and within afflicted nervous tissue. Many W3/13-reactive T lymlhocytes of both helper and suppressor/cytoxic phenotypes appeared in close contact with these Ia-expressing non-T cells, particularly within the infiltrates. B lymphocytes and plasma cells were relatively few and mainly found close to endoneurial vessels.