Latex bread technique for detection of the plaque-forming cell response to teratocarcinoma tumor antigens

Abstract

A latex bead technique modified for measuring the plaque-forming cell (PFC) response to teratocarcinoma tumor antigens in syngeneic animals is described. With this method one can detect both the primary (IgM) and the secondary (IgG) immune response to tumor antigens. Optimal detection of the PFC response depends on the proper ratio of sheep red blood cells to latex beads and the dose of tumor cell antigen used for immunization. The presence of fetal calf serum interfered with immunization of animals and the coating of the latex beads with the tumor cell antigens. The plaques obtained in response to immunization with teratocarcinoma cell antigens varied in size, probably reflecting the complex immune response to more than one class of antigens on tumor cells.

Immune response of mice exposed to cis-diamminedichloroplatinum

“…Purified pneumococcal polysaccharide type III (SIII) was a generous gift from Dr Phillip J. Baker, NIH, Division of Microbial Immunity. The immunologic properties of SIII from this source have been described previously [1,3,4]. Sheep erythrocytes (SRBC) obtained from a single animal were purchased from Dutchland (Swiftwater, Pa), stored in Alsever's solution, and washed three times in sterile saline before use.…”

“…Then 50 ~tl 20% SRBC and, lastly, 700 btl 1% SeaPlaque agarose (Marine Colloids, Rockland, Me), were mixed well on a vortex and immediately poured onto premarked glass sliedes [1]. After solidification 143 (2-3 min) slides were incubated in a humidified atmosphere at 37 ° C for 3-4 h. Plaques were enumerated with the aid of a dissecting microscope.…”