Developmental Genetics Laboratory, Department of Biological Sciences, Indian Institute of Science Education and Research (IISER) Mohali, Knowledge City, Punjab, India.
Int J Dev Biol. 2020;64(4-5-6):319-329. doi: 10.1387/ijdb.190215lm.
Drosophila hemocytes are majorly associated with immune responses, but they also undertake several non-immune functions that are crucial during various stages of development. The activity and behaviour of hemocytes are least documented during the metamorphic phase of fly development. Here we describe the activity, form and behaviour of the most abundant type of hemocyte in Drosophila melanogaster, the "plasmatocyte," throughout pupal development. Our study reveals different forms of plasmatocytes laden with varying degrees of histolyzing debris (muscle and fat) which extend beyond the size of the cell itself, highlighting the phagocytic capacity of these plasmatocytes. Interestingly, the engulfment of apoptotic debris by plasmatocytes is an actin-dependent process, and by the end of metamorphosis, clearance is achieved. The uptake of apoptotic debris consisting of muscles and lipids by the plasmatocytes provides us a model that can be employed to dissect out the relevant components of macroendocytosis and lipid-loaded phagocytosis. This understanding, by itself, is crucial for addressing the emerging role of phagocytes in physiology and pathophysiology.
果蝇血细胞主要与免疫反应有关，但它们也承担着几个非免疫功能，这些功能在发育的各个阶段都至关重要。在果蝇发育的变态阶段，血细胞的活动和行为记录最少。在这里，我们描述了在蛹发育过程中，在果蝇中最丰富的血细胞类型“浆血细胞”的活性、形态和行为。我们的研究揭示了不同形式的浆血细胞，它们携带不同程度的组织分解（肌肉和脂肪）碎片，超出了细胞本身的大小，突出了这些浆血细胞的吞噬能力。有趣的是，浆血细胞吞噬凋亡碎片是一个肌动蛋白依赖的过程，到变态期结束时，清除过程完成。浆血细胞吞噬含有肌肉和脂质的凋亡碎片为我们提供了一个模型，可以用来剖析巨胞饮和负载脂质的吞噬作用的相关成分。这种理解本身对于阐明吞噬细胞在生理学和病理生理学中的新作用至关重要。
