Albuquerque C M, Ham P J
Department of Biological Sciences, Keele University.
Parasitology. 1995 Jan;110 ( Pt 1):1-6. doi: 10.1017/s0031182000080987.
Mixed infections with malarial (Plasmodium gallinaceum) and filarial (Brugia pahangi) parasites were carried out in 8 trials with filaria susceptible (REFM) and filaria refractory (REP-RR) Aedes aegypti strains. A secondary infection with B. pahangi microfilariae (mff) by intrathoracic inoculation, reduced the development rate of a pre-existing P. gallinaceum infection. The level of reduction ranged from 9.5 to 49% in REFM and from 50 to 90% in REP-RR. An immune response against oocysts was seen as melanization in mosquitoes with a double infection in the strain refractory to B. pahangi (REP-RR) and a reduction in oocyst size in both mosquito strains. Melanization was not observed in mosquitoes infected only with P. gallinaceum. This may indicate that activation of the prophenoloxidase (PPO) cascade in response to mff in the haemolymph can also be addressed against oocysts in the midgut. No significant difference in the number of filarial parasites recovered was observed when comparing groups with a single or double infection. Retardation in development of filaria larvae was observed in mosquitoes with double infection (REFM strain), together with melanization and a higher rate of abnormal development. Nutritional deficiency caused by superinfection might also be responsible for the delay in filarial development and reduced oocyst size.
在8次试验中，对易感染丝虫的（REFM）和难感染丝虫的（REP-RR）埃及伊蚊品系进行了疟原虫（鸡疟原虫）和丝虫（彭亨布鲁线虫）的混合感染。通过胸腔内接种进行彭亨布鲁线虫微丝蚴（mff）的二次感染，降低了先前存在的鸡疟原虫感染的发育率。在REFM中，降低水平为9.5%至49%，在REP-RR中为50%至90%。在对彭亨布鲁线虫难治的品系（REP-RR）中，双感染的蚊子中可见针对卵囊的免疫反应表现为黑化，并且两种蚊子品系的卵囊大小均减小。仅感染鸡疟原虫的蚊子中未观察到黑化现象。这可能表明，血淋巴中对mff的反应激活酚氧化酶原（PPO）级联反应也可针对中肠中的卵囊。比较单感染组和双感染组时，回收的丝虫寄生虫数量没有显著差异。在双感染的蚊子（REFM品系）中观察到丝虫幼虫发育延迟，同时伴有黑化和更高的异常发育率。重复感染引起的营养缺乏也可能是丝虫发育延迟和卵囊大小减小的原因。
