[Clinical Significance of CCRL2 Regulating Platelet Function in Pediatric Chronic Immune Thrombocytopenia].

OBJECTIVE

To investigate the expression of C-C motif chemokine receptor-like 2 (CCRL2) on platelets in children with chronic primary immune thrombocytopenia(ITP), and its effect on platelet function.

METHODS

11 chronic ITP patients who were diagnosed at the Department of Hematology of Children's Hospital of Soochow University from April 2023 to September 2024, and 12 control cases were enrolled in this study. Both the expression of CCRL2 on platelets was measured, and the effects of Ccrl2 deletion on platelet production and function were evaluated.

RESULTS

Deletion of Ccrl2 did not affect platelet counts and megakaryopoiesis, but significantly impaired the maximum aggregation rate, P-selectin expression, and adhesive ability to collagen I of platelets. In addition, the levels of CCRL2 and CD36 on platelets in children with chronic ITP were significantly decreased. However, the absolute number of neutrophils and the concentrations of Proprotein Convertase Subtilisin/Kexin Type 9 (PCSK9) and Defensin Alpha 1(DEFA1) were significantly increased.

CONCLUSION

The weakened platelet function in children with chronic ITP may be related to the decreased CCRL2 expression.