Department of Animal and Plant Sciences, University of Sheffield, Sheffield S10 2TN, UK.
J Insect Physiol. 2011 Jul;57(7):1023-32. doi: 10.1016/j.jinsphys.2011.04.020. Epub 2011 May 5.
The honey bee, Apis mellifera, is an ideal system for investigating ontogenetic changes in the immune system, because it combines holometabolous development within a eusocial caste system. As adults, male and female bees are subject to differing selective pressures: worker bees (females) exhibit temporal polyethism, while the male drones invest in mating. They are further influenced by changes in the threat of pathogen infection at different life stages. We investigated the immune response of workers and drones at all developmental phases, from larvae through to late stage adults, assaying both a constitutive (phenoloxidase, PO activity) and induced (antimicrobial peptide, AMP) immune response. We found that larval bees have low levels of PO activity. Adult workers produced stronger immune responses than drones, and a greater plasticity in immune investment. Immune challenge resulted in lower levels of PO activity in adult workers, which may be due to the rapid utilisation and a subsequent failure to replenish the constitutive phenoloxidase. Both adult workers and drones responded to an immune challenge by producing higher titres of AMPs, suggesting that the cost of this response prohibits its constant maintenance. Both castes showed signs of senescence in immune investment in the AMP response. Different sexes and life stages therefore alter their immune system management based on the combined factors of disease risk and life history.
蜜蜂，即 Apis mellifera，是研究免疫系统个体发育变化的理想系统，因为它在真社会性的社会等级制度下结合了全变态发育。成蜂中，雄性和雌性蜜蜂受到不同的选择压力：工蜂（雌性）表现出时间多态性，而雄蜂则投资于交配。它们还受到不同生命阶段病原体感染威胁变化的影响。我们在所有发育阶段（从幼虫到晚期成虫）检测了工蜂和雄蜂的免疫反应，同时检测了固有（酚氧化酶，PO 活性）和诱导（抗菌肽，AMP）免疫反应。我们发现，幼虫蜜蜂的 PO 活性水平较低。成年工蜂比雄蜂产生更强的免疫反应，并且在免疫投资方面具有更大的可塑性。免疫挑战导致成年工蜂的 PO 活性降低，这可能是由于迅速利用和随后无法补充固有酚氧化酶所致。成年工蜂和雄蜂都对免疫挑战产生了更高的 AMP 滴度反应，这表明这种反应的代价使其无法持续维持。两种蜂都表现出免疫投资在 AMP 反应中衰老的迹象。因此，不同的性别和生命阶段根据疾病风险和生活史的综合因素改变了它们的免疫系统管理。
