A miniaturized in vitro diffusion culture system.

A miniaturized diffusion culture apparatus holding 24 individual cultures and utilizing 1/10 the cells and volume of standard Marbrook-type cultures is described. This system was evaluated by studying the anti-sheep erythrocyte response of spleen cells from unprimed or primed and boosted mice. Compared to parallel Mishell--Dutton plate cultures memory responses in mini-diffusion cultures rise more slowly, peak 1--2 days later and thereafter decline less rapidly.

Contact sensitivity in mice measured with thymidine labeled lymphocytes.

An ear assay was used to detect delayed responses in mice. Animals were sensitized and subsequently injected with 3H thyminedeoxyryribose to label antigen sensitive cells. Each animal was given a control and a test ear challenge and the respective responses were assessed by scintillation counting of 3H in cells which had accumulated at the reaction site.