Interactions of rodent malarial parasites with Friend erythroleukemia cells in vitro

The ability of Plasmodium chabaudi and P. yoelii to bind to Friend erythroleukemia cells in vitro was examined. Extensive binding of P. yoelii and weaker binding of P. chabaudi was observed. Binding to mouse fibroblasts was not seen, although there was some binding to cells of a mouse mastocytoma. The binding of P. yoelii to Friend cells was sensitive to specific antiserum. The development of P. berghei and P. yoelii in Friend cells was followed by microscopic examination and measurement of the infectivity of those cells in mice. Friend cells infected with both species appeared to develop morphologically normal intracellular forms of the parasites. P. yoelii-infected cells were infective in sensitive mice for 3 days after addition of the parasites, and this infectivity was not sensitive to treatment in vitro with mouse anti-P. yoelii serum.