PROTECTIVE PROPERTIES OF <i>ECHINOCOCCUS MULTILOCULARIS</i> PROTOSCOLEX ANTIGENS IN COMBINATION WITH THE IMMUNOMODULATOR RONCOLEUKIN IN SECONDARY ALVEOLAR ECHINOCCOCOSIS

Objective of research: Estimation of protective effects of Echinococcus multiocularis protoscolex cell antigens in combination with the immunomodulator Roncoleukin in experimental alveolar echinococcosis. Materials and methods: In this experiment we used cellular antigens - E. multilocularis protoscoleces cell metabolites cultivated in artificial substrate [Berezhko V.K. and co-authors, 2001], and immunomodulator Roncoleukin (pharmaceutical form of recombinant human interleukin-2 (rhIL-2). Experiments were conducted on 48 white outbreed mice with the mass of 18-20 g. divided into 4 equal groups. The first group of mice received Roncoleukin twice subcutaneously, with a ten-day interval at the dose of 180 МЕ in 0,2 ml of sterile 0,9% sodium chloride solution; the second group (according to the same schedule) - cell antigens at the dose of 60 mсg protein antigen per mouse and Roncoleukin at the same dose; the third (according to the same schedule) - cell antigens at the dose of 60 mсg protein antigen per mouse. The fourth group (controls) received 0,2 ml of sterile 0,9% sodium chloride solution per mouse. After 20 days, all mice were infected with protoscoleces and acephalocysts of E. multilocularis at the dose of 750±50 ind./mouse. On the 90th day of invasion, the experimental mice were killed and underwent autopsy according to the «Rules for conducting works using experimental animals». Results and discussion: The results of the experiment showed that the protective effect in the first group receiving Roncoleukin was 58,3%; the third group (cell antigens of protoscoleces - 66,7%); the second group (complex preparation containing Roncoleukin and cell antigens)- 83,3%. Single larval cysts on liver parenchyma without embryonic elements were detected in 2 mice only of the group receiving a complex preparation. In the other two groups, parasitic cysts were registered in 5 and 4 mice with the mass 125,3±21,8 - 142,2±38,02 mg and the size 11,98±4,2 - 12,35±3,46 mm, respectively. All mice from the control group were infected. Numerous larval cysts (size 15,64±1,46mm and mass 580,8±222,09 mg) with developing viable protoscoleces were found in abdomen and internal organs