Ultrastructural Localization of 2,4‐dinitrophenyl Groups on Draining Lymph Node Cells of Guinea Pigs Following Skin Painting With 2,4‐dinitrochlorobenzene

Abstract

The distribution of DNP groups on cells taken from draining lymph nodes of guinea pigs 12 hours after painting the skin with DNCB was examined by scanning immunoelectron microscopy using antibody directed against DNP groups with bacteriophage T4 as a visual marker. The studies showed that DNP groups were distributed on the surface of the cells, demonstrating some differences in distribution pattern among the cells. The incidence of cells on which DNP groups were detected was approximately 60% in the normal animals, higher than that detected by a previous immunofluorescent study. The incidence was markedly reduced to approximately 3% by pretreatment with tolerogen, DNBSO3Na. DNP groups were detected on the surface of the cells forming both rabbit red cell rosettes and complement coated red cell rosettes. It is suggested that DNCB penetrates through the skin into the lymphatics carrying lymph from the painted site and combines with cell membrane components in the peripheral lymphoid system.

Oral and epicutaneous desensitization in urushiol contact dermatitis in guinea pigs sensitized by 2 methods of different sensitizing potency

“…Takei (17) reported that after oral dosing of DNCB, the DNP group was observed in the epithelial cells of the gastrointestinal mucosa, mesenteric lymph nodes, Peyer's patches, spleen and peripheral blood lymphocytic cells, a finding common to that obtained after epicutaneous dosing showing the presence of the DNP group at the site of application and in the regional lymph nodes, spleen and peripheral blood lymphocytic cells. Scanning immunoelectron microscopic studies of the distribution of epicutaneous DNCB in guinea pigs revealed that the DNP group was present on the surface of epidermal and lymphocytic cells, indicating that DNCB binds with components of the plasma membrane of these cells in vitro (18,19).…”