Characterization of Th1- and Th2-associated chemokine receptor expression in spleens of patients with immune thrombocytopenia.

PURPOSE: In view of the numerous clinical observations and laboratory studies that suggest a critical role for the spleen in immune thrombocytopenia (ITP) pathophysiology, we aimed to characterize Th1-associated chemokine receptors CXCR3 and CCR5 and Th2-associated chemokine receptor CCR3 in spleens of ITP patients and assess the significance of their differential expression in the clinical setting. METHODS: The histopathology of spleens was observed using hematoxylin-eosin staining (HE), and the positive rate of CXCR3, CCR5 and CCR3 expression in spleens of 24 ITP patients and 12 patients with traumatic splenic rupture as normal controls was detected by immunohistochemistry using the SP method. CXCR3, CCR5 and CCR3 protein expression was analyzed by Western blot and mRNA levels were investigated by real-time polymerase chain reaction (RT-PCR). RESULTS: Reactive hyperplasia could be seen in follicles of the white pulp, the germinal central zone was enlarged and the marginal zone was thickened, the central arteries were thickened and fibrotic, and the density of the capillary vessel was increased in ITP patients. ITP group displayed a higher rate of expression of Th1-associated chemokine receptors CXCR3 and CCR5 (83.3% vs. 75%, 100% vs. 83.3%) but lower rate of expression of Th2-associated chemokine receptor CCR3 (50% vs. 66.7%) compared with the controls (P < 0.05, respectively). Western blot analysis revealed that CXCR3 and CCR5 protein expression was significantly increased in ITP patients while CCR3 was significantly reduced (P < 0.05, respectively). Meanwhile, ITP patients displayed increased mRNA levels of CXCR3 and CCR5 but decreased gene expression of CCR3 (P < 0.05, respectively). CONCLUSION: The data suggested that the abnormal expression of Th1/Th2 chemokine receptors may participate in splenic immune disorder in patients with ITP. Using corresponding inhibitors may inhibit Th1-dominant expression and mitigate the progress of the disease.

[Expression of CXCR3 and CCR5 chemokine receptor in spleens of patients with primary immune thrombocytopenia].

OBJECTIVE: To study CXCR3 and CCR5 chemokine receptor expression in spleens of patients with primary immune thrombocytopenia (ITP) and its clinical significance. METHODS: The splenectomy specimens from 10 ITP patients (ITP group) and 8 patients with traumatic splenic rupture (normal control group) were studied. Immunohistochemistry (IHC) was used to study the positive rate of CXCR3 and CCR5. Western blot was performed to detect CXCR3 and CCR5 protein expression, while real-time polymerase chain reaction (RT-PCR) was conducted to analyze their mRNA expression. RESULTS: The positive rate of CXCR3 and CCR5 were both higher in ITP group (90% and 100%, respectively) than those in control group (75% and 87.5%, respectively)(P < 0.05). The differences were statistically significant (P < 0.05). Protein and mRNA level of CXCR3 in ITP group were 3.0 and 3.5 times as high as those in control group, respectively. Those of CCR5 in ITP group were 1.2 and 1.7 times as high as those in control group, respectively. CONCLUSION: High expression of CXCR3 and CCR5 may play a part in the splenic immune disorders in patients with ITP.