Changes in lymphocyte adhesiveness during contact sensitization.

Lymphoid cells from the draining lymph nodes of mice 3 days after oxazolone application were found to be more adhesive to each other and to glass than cells from unsensitized nodes. Examination of the temporal sequence of changes during contact sensitization showed that during the first 4 days after oxazolone application there was an increase in both the cellularity of the draining node and in the intercellular adhesiveness of cells from the draining node, which persisted for at least 14 days. There was also an increase in the lymphoblast content; however, this was transient, peaking at Day 4 before returning almost to normal by Day 7. The intercellular adhesiveness of a lymphoblast-enriched subpopulation from the draining node was greater than the adhesiveness of a small lymphocyte subpopulation from the same node. However, the adhesiveness of both these subpopulations were greater than that of normal, unsensitized lymphoid cells. The implications of a change in cellular adhesiveness on the migratory properties in vivo of lymphocytes are discussed.