Life span of circulating blood cells in ginbuna crucian carp (Carassius auratus langsdorfii)

Life span and half-life of different populations of circulating peripheral blood cells from ginbuna crucian carp (Carassius auratus langsdorfii) were investigated. Erythrocytes or peripheral blood leukocytes (PBL) were stainedex vivowith a fluorescent cell linker kit, then reinjected into the same fish. Blood cells were reisolated from peripheral blood and the decrease in levels of labelled cells was plotted against time. The decrease of stained cells in peripheral blood was exponential, from which the half-life of the cells was calculated. Circulating erythrocytes showed a half-life of approximately 51 days. However, a few erythrocytes survived in the peripheral blood for more than 270 days. The life span of circulating thrombocytes was estimated to be approximately 70 days, with a half-life of less than 5 days. The half-life of circulating monocytes and granulocytes was between 2 and 3 days, respectively, with their life span varying from between 2 and 27 days, while the life-span of circulating lymphocytes ranged from between 10 and 23 days. However, some stained lymphocytes persisted in the peripheral blood for more than 145 days and these may represent memory cells.