Opisthorchis viverrini:Partial success in adoptively transferring immunity with spleen cells and serum in the hamster

Abstract

Three groups of golden Syrian hamsters received intraperitoneally either, (1) 1 × 107 spleen cells, (2) 0.5 ml. serum or, (3) 1 × 107 spleen cells plus 0.5 ml. serum, from donors infected 6 weeks previously with 25 Opisthorchis viverrini metacercariae, one day before and at the same time as challenge with 25 metacercariae. Three groups of control animals received the same quantities of spleen cells, serum or an admixture of both from normal non-infected donors in the same manner followed by challenge with 25 metacercariae.Animals were killed six weeks after challenge, livers and extrahepatic biliary systems carefully removed, and liver worm burdens estimated. Additionally, parasitic egg counts were performed on pooled faeces samples collected one hour prior to death.Animals receiving spleen cells, serum, or an admixture of both, from normal non-infected donors had mean worm burdens of 11.44, 12.00 and 12.66, respectively. Animals receiving spleen cells, serum, or both, from infected donors had mean worm burdens of 9.88, 7.77 and 12.00, respectively. There were no significant differences in mean worm burdens between control and experimental groups. However, a substanial reduction in parasitic faecal egg counts and subsequently mean egg production per worm was observed in all 3 groups of animals receiving spleen cells, serum, or both, from infected donors when compared to their respective control group.These findings are discussed in relation to adoptive transfer studies performed with other helminths and their possible relevance to naturally acquired immunity is commented on.

Susceptibility of experimental animals to reinfection with Clonorchis sinensis

“…Furthermore, several studies reported contradictory data on the protective immunity against reinfection with O. viverrini in hamsters. Prior infection with O. viverrini did not protect hamsters against reinfection by the same parasite (Sirisinha et al, 1983), and adoptive transfer of spleen cells and sera from infected hamsters produced a moderate, but insignificant reduction in the worm burden in recipient hamsters (Flavell et al, 1980).…”

Immunization and challenge shown by hamsters infected withOpisthorchis viverrinifollowing exposure to gamma-irradiated metacercariae of this carcinogenic liver fluke

“…We also observed that immunization of hamsters with γ-irradiated MC of O. viverrini resulted in decreased infection and fecundity upon challenge infection with intact/wild-type MC. Passive transfer of immune spleen cells and serum to protect against O. viverrini has been examined, but failed to induce resistance to reinfection in hamsters (Flavell et al , 1980). The immunization of hamsters with a soluble lysate of adult worms before challenge infection afforded modest protection, a 30% reduction of worms (Sirisinha & Wongratanacheewin, 1986).…”

“…Notwithstanding the clinical relevance of this model, it has been under-studied as a model for the development of vaccines. This is despite the outcome of passive transfer to naïve hamsters of spleen cells and/or sera from infected hamsters that results in reductions in fecundity compared to control hamsters, implying that both humoral and cellular factors contribute to this protective outcome (Flavell et al , 1980). In addition, immunization with parasite extracts has also induced modest reductions in fluke burdens (Sirisinha & Wongratanacheewin, 1986).…”

Relationships Between IgG, IgM, IgE and Resistance to Reinfection During the Early Phase of Infection withClonorchis sinensisin Rats

“…IgE was observed to play a pre-emminent role in protective immunity in rat schistosomiasis (Rousseaux-Prevost et al, 1978). In another study, hamsters that were repeatedly infected with O. viverrini (Sirisinha et al, 1983) or receiving either serum or spleen cells from infected hamsters showed a reduction of egg output or EPG (eggs per gram) per worm (Flavell et al, 1980). When rabbits were re-infected with C. sinensis repeatedly they become partially protected and produced elevated levels of antiparasitic antibodies (Yen and Chen, 1985).…”