Extraovarian pelvic serous tumor with marked calcification.

We report two cases of low-grade extraovarian pelvic serous tumor. Each contained large numbers of psammoma bodies. The tumors belong to the small group of serous carcinomas that arise from the peritoneum.

Variability in parasite protein antigen structure and protective immunity to malaria.

Cloned lines of the rodent malaria parasite Plasmodium chabaudi (denoted AS and CB) have been used to investigate the strain specificity of immunity to malaria. One defined difference between these lines is their expression of serologically and structurally distinct forms of an Mr 250Kd parasite-encoded antigen. This antigen is a member of a family of schizont/merozoite-associated polypeptides which have been implicated in the induction of protective immunity to rodent, simian and human malaria parasites.

Isolation and partial characterization of the tegumental outer membrane of schistosomula of Schistosoma mansoni.

Separation of the external membranes from freshly converted mechanical schistosomula of Schistosoma mansoni was achieved by osmotic shock under hypertonic conditions, followed by mechanical shearing and ultracentrifugation. Prior to treatment, the schistosomula were surface labeled by introduction of N-DNP-epsilon-aminocaproylphosphatidylethanolamine molecules into their lipid bilayer followed by anti-DNP antibodies and stained with either 125I-protein-A or ferritin labeled secondary anti-DNP antibodies. This label provided a membrane marker by which the purity of the preparation could be assessed at each stage.

A possible molecular basis for strain specific immunity to malaria.

A 250 kDa antigen implicated in the induction of protective immunity to Plasmodium chabaudi was examined with a panel of 11 monoclonal antibodies in cloned parasite lines. 2 antibodies cross-reacted with the different parasite lines while 9 were specific for one line. This antigenic diversity was correlated with major differences in one dimensional peptide maps between the purified antigen from different lines of parasites.

A method of introducing lipid-conjugated antigens into the surface of schistosomula.

Introduction of synthetic antigens into the surface of schistosomula of Schistosoma mansoni was achieved by brief incubation of the worms with liposomes carrying the lipid-bound antigens in their bilayers. Three-hour-old schistosomula were surface-labeled with lipid-conjugated dinitrophenyl (DNP) groups by using liposomes made of egg lecithin-N-dinitrophenil-epsilon-aminocaproyl-phosphatidylethanolamine (5:1). The DNP groups incorporated in this way could be detected for more than 21 hours in vitro by using rabbit anti-DNP antibodies stained with fluorescein isothiocyanate-conjugated goat anti-rabbit IgG.