Posttransplant diffuse large B-cell lymphoma of "lymphomatoid granulomatosis" type.

The exact relationship between lymphomatoid granulomatosis (LyG) and posttransplant lymphoproliferative disorders (PTLDs) is not clear. Both are observed in immunodeficient patients and are Epstein-Barr virus driven. These disorders are, however, considered distinct based upon the immune response elicited; LyG is T-cell rich while PTLDs are T-cell poor. We describe a case of LyG-type diffuse large B-cell lymphoma (DLBCL) in a lung transplant recipient. The unusual features include rare occurrence of LyG in a posttransplant setting, systemic involvement by LyG variant of DLBCL in a solid organ transplant recipient, paucity of T-cells in this LyG type lymphoma, and subcutaneous panniculitic pattern in a B-cell lymphoproliferative disorder. This first report of systemic LyG variant of DLBCL in a posttransplant setting has features suggesting similarities and overlap between LyG and PTLD.

Antiidiotype induction therapy: evidence for the induction of immune response through the idiotype network in patients with ovarian cancer after administration of anti-CA125 murine monoclonal antibody B43.13.

The immune status of ovarian cancer patients receiving anti-CA125 murine monoclonal antibody B43.13 was evaluated by measuring antiidiotypic antibodies (Ab2), antiantiidiotypic antibodies (Ab3), antiisotypic human antimouse antibodies (HAMA), interferon-gamma, and CA125 levels in the serum. A specific assay was developed for the determination of Ab2 antibodies using chimeric MAb B43.13. Of the 50 patients studied, 26 had elevated levels of Ab2. Eleven of these 26 patients also had high titer of antiantiidiotypic (Ab3) antibodies. Eight of the 22 patients analyzed had increased interferon-gamma levels. A tentative correlation was found between survival of these patients' antiidiotype induction.

Antimicrobial action of antibodies against Giardia muris trophozoites.

The activities of immune serum and trophozoite-specific MoAb were examined in vitro and in vivo. Immune serum and anti-Giardia muris MoAb caused immobilization of the trophozoites in vitro and were cytotoxic for trophozoites in the presence of exogenous complement. Both immune serum obtained from experimentally infected mice and anti-G. muris MoAb administered directly into the duodenum of mice significantly reduced the number of trophozoites in the small intestine during the acute phase of the infection. These results suggest that serum antibodies play a central role in the elimination of the primary Giardia infection.

Effects of source of metacercariae on experimental infection of Zygocotyle lunata (Digenea: Paramphistomidae) in CD-1 mice.

Outbred (CD-1 strain) mice were infected experimentally with metacercariae of Zygocotyle lunata obtained from naturally infected Helisoma trivolvis. Growth, survival, and fecundity of the parasite and gross pathology in the host were evaluated. Metacercariae from 5 snail sources produced 3 patterns of growth and survival: significantly smaller worms that survived less than 4 wk and did not mature, significantly larger worms that matured but survived less than 6 wk, and worms of intermediate size that matured and lived at least 19 wk. Parasite maturation (at 3-4 wk) and egg production (14 eggs.worm-1.hr-1) were similar among infections from different sources. Ceca of mice with infections at least 4 wk old were enlarged with localized mucosal alteration at the site of parasite attachment, but there was no evidence of splenomegaly. The differences in infection due to the source of metacercariae within 1 strain of final host were similar to differences reported among other species of final host. These results suggest that variation associated with the intermediate host may confound studies of specificity to the definitive host.

Differential recognition of saliva antigens from the ixodid tick Amblyomma hebraeum (Acari: Ixodidae) by sera from infested and immunized rabbits.

We determined the protein composition and antigenic content of saliva from Amblyomma hebraeum female ticks of different weight classes. The mean protein concentration of saliva of small partially fed ticks (< 100 mg) was 333 +/- 83 micrograms/ml and that of large partially fed ticks (150-420 mg) was 59 +/- 14 micrograms/ml. The reduction in concentration mostly was caused by the significantly higher fluid volume per minute secreted by large ticks. Polypeptide analysis of saliva indicated the presence of a protein (14 kilodaltons [kD]) only in ticks weighing < 60 mg. Other saliva proteins of 21 and 26 kD were present only in ticks weighing < 150 mg, whereas 68-kD protein was absent or very faint in ticks > 100 mg. Immunoblot analysis indicated that sera from rabbits infested with ticks recognized 13 saliva antigens ranging in size from 23 to 200 kD. The antigens were present in detectable quantities in the saliva of small ticks only. In contrast, the sera from rabbits immunized with tick saliva recognized only four antigens from 63 to 200 kD. The 63-kD antigen was not present in the saliva of large ticks. These data indicate that the saliva of A. hebraeum from small ticks is antigenically more complex than that of large ticks and that the route of immunization influences the humoral immune response of the host to the saliva antigens.