ISSN:
1550-7408
Source:
Blackwell Publishing Journal Backfiles 1879-2005
Topics:
Biology
Notes:
SYNOPSIS. A previous study has shown that a strain of Plasmodium berghei had become modified following serial passage through rats and tissue culture in a medium containing lamb serum. Mice infected with this strain showed a longer survival time and some of the mice recovered. The recovered mice developed a true immunity to reinfection with the modified strain and the parent strain. It was thought that this effect was due to the serum contained in the culture medium. Consequently the experiments were repeated and other strains developed using rat and calf serum. The strain derived, after 10 serial passages alternately through rats and tissue culture containing rat serum, retained the characteristics of the parent strain, i.e., all mice infected with this strain died; the majority within 19–21 days. Mice infected with a strain derived from the series utilizing calf serum showed a significantly longer survival time and 8 mice out of 87 survived. The strain derived by using lamb serum yielded results similar to those previously reported and after 8 serial passages 20 mice out of 65 survived infection. The hypothesis is advanced that P. berghei is antigenically heterogeneous, much as has been shown for the trypanosomes. It is thought that opsonins contained in the serum of the tissue culture medium render certain antigenic types more liable to phagocytosis and therefore the in vitro treatment acts as a screening process, as the case might be, leaving those types most easily recognized by the mouse and hence evoking an effective immune response.
Type of Medium:
Electronic Resource
URL:
http://dx.doi.org/10.1111/j.1550-7408.1964.tb01745.x
