Akue J P, Morelli A, Moukagni R, Moukana H, Blampain Azzibrouck G
Department of Medical Parasitology, International Centre for Medical Research, Franceville (CIRMF), B.P. 769, Franceville, Gabon.
Parasite. 2003 Sep;10(3):263-8. doi: 10.1051/parasite/2003103263.
Six mandrills were immunized with 150 Loa loa infective stage larvae (L3) irradiated with 40 Krad, and challenged with 100 L3, 60 days after initial vaccination. The parasitological outcome of this immunization was compared to results from six mandrills infected with normal L3. No clear association was seen between vaccination and microfilaremia until day 245 when a significant drop in the level of microfilaria occurred in vaccinated compared to infected animals (5 vs 10 mf/ml; p = 0.012). A one-year follow-up of the humoral immune response showed a strong adult, microfilariae (Mf) and L3 specific IgG response, with distinct profiles for each extract. In immunized animal a significant decrease in antibody level was systematically observed between days 90-145 for the anti-L3 and anti-adult IgG. However, in the same group anti-Mf antibody levels that peaked around 160-175 days post-challenge, were inversely correlated with the decrease in Mf density between day 200 and day 386. These results suggest that immunization with irradiated L3 using these specific conditions may affect the appearance of Mf.
六只山魈用40拉德辐射的150条罗阿丝虫感染期幼虫（L3）进行免疫，并在初次接种疫苗60天后用100条L3进行攻击。将这种免疫的寄生虫学结果与六只感染正常L3的山魈的结果进行比较。在第245天之前，未观察到疫苗接种与微丝蚴血症之间有明显关联，此时与感染动物相比，接种疫苗的动物微丝蚴水平显著下降（5对10条微丝蚴/毫升；p = 0.012）。对体液免疫反应进行的一年随访显示，对成虫、微丝蚴（Mf）和L3有强烈的特异性IgG反应，每种提取物的反应谱不同。在免疫动物中，在第90 - 145天期间，抗L3和抗成虫IgG的抗体水平系统性显著下降。然而，在同一组中，抗Mf抗体水平在攻击后约160 - 175天达到峰值，与第200天至第386天期间Mf密度的下降呈负相关。这些结果表明，在这些特定条件下用辐射的L3进行免疫可能会影响Mf的出现。
