Splenic conditioning

Q: What is "splenic conditioning" in Red Blood Cells (RBCs) circulation?

Answer: After splenectomy, there is a surge of variable target cells, acanthocytes, and other RBC changes, particularly Howell-Jolly bodies, which are nuclear fragments.

The spleen is responsible for removing excess membrane from RBCs. This process is known as "splenic conditioning." The exact mechanism is not well understood, although the reduction in RBC lipid content suggests that processes involving lipases are involved. 

In the first few weeks after splenectomy, target cells count for 2 to 10 percent of all circulating RBCs. These cells have an increased membrane, a higher surface-to-volume ratio, and reduced osmotic fragility. These RBCs eventually lose their excess lipid by conditioning at other sites and the gradual disappearance of target cells.

#hematology

#physiology

References:

1. de Haan LD, Werre JM, Ruben AM, et al. Alterations in size, shape and osmotic behaviour of red cells after splenectomy: a study of their age dependence. Br J Haematol 1988; 69:71.

2. Singer K, Weisz L. The life cycle of the erythrocyte after splenectomy and the problems of splenic hemolysis and target cell formation. Am J Med Sci 1945; 210:301.

3. Singer K, Miller EB, et al. Hematologic changes following splenectomy in man, with particular reference to target cells, hemolytic index, and lysolecithin. Am J Med Sci 1941; 202:171.