Biozentrum Grindel und Zoologisches Museum der Universität Hamburg, Martin-Luther-King-Platz 3, 20146 Hamburg, Germany.
Comp Biochem Physiol A Mol Integr Physiol. 2013 Apr;164(4):629-37. doi: 10.1016/j.cbpa.2013.01.021. Epub 2013 Feb 4.
It was asked whether variations in hemocyte counts in a mussel can be explained by mechanisms known to govern the leukocyte number in vertebrates. Hemolymph of 25 freshly collected Mytilus edulis contained (4.2±1.75)×10(6)cells/mL including basophilic and eosinophilic granulocytes and 6.6±5.5% hyalinocytes (15 animals). After 12 or 30days under optimal laboratory conditions, hemocytes in circulation decreased to less than 1×10(6)/mL, the lowest number observed being 5×10(5)cells/mL. Within 2min of a stressful stimulus, cell numbers doubled or increased by a factor of 3 or 4. After stressing mussels by keeping them out of water for 1h, cell counts were as high as 1.2×10(7)cells/mL. The quick rate of increase in cell counts is not due to hemocyte proliferation. In mussels, returned to optimal water conditions, cell numbers dropped following an exponential decay curve (y=5.6865·(0.9936(X)). Not all hemocyte types decreased in number to the same extent. After a strong decrease in the total cell count induced by injection of LPS, the remaining hemocyte population contained a larger percentage of basophils. This indicated the disappearance of eosinophilic cells from the circulation. Stress situations caused their return. Hemocytopenia or stress-induced hemocytosis in M. edulis, both in conjunction with changes in the percentage of granulocytes present, resembles margination/demargination processes in mammals where the concentration of circulating leukocyte subsets depends on the expression of adhesive receptor-ligand molecules on the surface of specific leukocyte types and vascular endothelial cells. In Mytilus edulis, variations in the concentration of distinct cell groups excluded heart activity to explain cell fluctuations. Furthermore, in this mussel, where hemocyte proliferation is not the reason for rapid hemocytosis, cell divisions were nevertheless demonstrated; they seem to be important in maintaining hemocyte homeostasis as 10-20% of cells in circulation possess the capacity to proliferate. They belong to the group of basophilic granulocytes.
有人问，贻贝血细胞计数的变化是否可以用已知控制脊椎动物白细胞数量的机制来解释。从 25 只新鲜采集的贻贝中采集的血淋巴含有（4.2±1.75）×10（6）个/mL 细胞，包括嗜碱性粒细胞和嗜酸性粒细胞，以及 6.6±5.5%的透明细胞（15 只动物）。在最佳实验室条件下 12 或 30 天后，循环中的血细胞减少到低于 1×10（6）/mL，观察到的最低数量为 5×10（5）个/mL。在受到应激刺激后的 2 分钟内，细胞数量增加了一倍或增加了 3 或 4 倍。将贻贝置于无水环境中 1 小时以对其施加压力后，细胞计数高达 1.2×10（7）个/mL。细胞计数的快速增加速度不是由于血细胞增殖所致。在贻贝中，当它们返回最佳的水条件时，细胞数量会遵循指数衰减曲线（y=5.6865·（0.9936（X）））下降。并非所有的血细胞类型数量都以相同的程度减少。在 LPS 注射引起总细胞计数强烈下降后，剩余的血细胞群中包含更多的嗜碱性粒细胞。这表明嗜酸性粒细胞从循环中消失。应激情况会导致它们的返回。贻贝的血细胞减少症或应激诱导的血细胞增多症，以及存在的粒细胞百分比的变化，类似于哺乳动物中的边缘/脱边缘过程，其中循环白细胞亚群的浓度取决于特定白细胞类型和血管内皮细胞表面上表达的粘附受体-配体分子。在贻贝中，不同细胞群浓度的变化排除了心脏活动来解释细胞波动。此外，在这种贻贝中，快速血细胞增多症不是由于血细胞增殖引起的，但是仍然进行了细胞分裂；它们似乎对于维持血细胞内稳态很重要，因为循环中的 10-20%的细胞具有增殖能力。它们属于嗜碱性粒细胞群。
