Study on the Role of Calreticulin Within Platelet from Adult Patients with Chronic Immune Thrombocytopenic Purpura

To observe the differences in proteins between adult patients with chronic immune thrombocytopenic purpura (ITP) and healthy adults. 30 patients with chronic ITP and 30 healthy controls were enrolled into the study. The platelet total protein was extracted from peripheral venous blood of 10 chronic ITP patients and 10 healthy controls respectively, and subjected to two-dimensional electrophoresis (2-DE) to find the differential protein spot between chronic ITP patients and healthy controls, then the differential protein spots were identified by mass spectrometry. Subsequently, platelets RNA and proteins were isolated from the other 20 chronic ITP patients and 20 healthy controls respectively, and used for confirming the 2-DE and mass spectrometry results by using reverse transcription-quantitative polymerase chain reaction (RT-qPCR) and enzyme linked immunosorbent assay (ELISA). 2-DE combined with mass spectrometry revealed that calreticulin (CRT) expressed normally within platelets from healthy controls, while it reduced within platelets from patients with chronic ITP. qPCR and ELISA confirmed that CRT was decreased at both RNA transcription and protein expression levels within platelets from chronic ITP patients compared with healthy controls. Decreased transcription and expression of CRT within platelets may play an important role in the pathogenesis of chronic ITP, which is worthy of further study.