Primary Immune Thrombocytopenia: A Translational Research Model for Autoimmune Diseases

Recombinant Thrombopoietin Effectively Shortens the Time to Response and Increases Platelet Counts in Elderly Patients with Severe Immune Thrombocytopenia

Background: This study was conducted to investigate the short-term efficacy and safety of rhTPO for the management of severe ITP in the elderly as first-line treatment. Methods: A total of 54 elderly patients with severe ITP were studied, including 39 patients treated with a combination regimen of rhTPO plus standard treatment (glucocorticoid; rhTPO group) and 15 patients treated with glucocorticoid treatment alone (control group). The response rate, time to initial response, peak platelet counts, and time to peak platelet counts were compared, and clinical characteristics correlated with the efficacy of rhTPO were analyzed. The efficacy of rhTPO in the elderly is comparable to the non-elderly in terms of the OR, CR, time to initial response, and peak platelet counts. Results: There were no differences in the overall response (OR) and the complete response (CR) in the rhTPO group compared to the control group. The time to initial response in the rhTPO group was shorter than that in the control group (p = 0.032). In patients without intravenous immunoglobulin (IVIg) and platelet transfusion, the peak platelet counts in the rhTPO group were higher than those in the control group (p = 0.003). Conclusions: Standard glucocorticoid treatment plus rhTPO effectively shortens the time to response and increases platelet counts in the elderly with severe ITP.

TCR CDR3 Sequencing as a Clue to Elucidate the Landscape of Dysimmunity in Patients with Primary Immune Thrombocytopenia

Background: Primary immune thrombocytopenia (ITP) is an autoimmune disorder. The existence of autoreactive T cells has long been proposed in ITP. Yet the identification of autoreactive T cells has not been achieved, which is an important step to elucidate the pathogenesis of ITP. Methods: ITP patients’ peripheral blood was collected prior to the treatment and one month after initiating dexamethasone treatment per related therapeutic guideline. Serum cytokines were profiled to examine T cell subtypes imbalance using a protein chip. TCR Vβ analysis in CD8+T cells of ITP patients, and TCR CDR3 DNA sequencing of CD4+T and CD8+T cells were performed to determine the autoreactive T cells’ clones. Results: Cytokine profiling revealed imbalanced distribution of T cells subtypes, which was confirmed by CD4+T and CD8+T cells’ oligoclonal expansion of TCR Vβ analysis and TCR CDR3 DNA sequencing. VDJ segments were found to be more frequently presented in ITP patients, when compared with health controls. There was an individualized CD4+T cell or CD8+T cell CDR3 sequence in each ITP patient. Conclusions: The present study revealed that T cell clones expanded in ITP patients’ peripheral blood, and each clone had an individualized TCR CDR3 sequence. The expanded T cell clones preferred to use some specific VDJ segment. Further studies are warranted to get access to individualized treatment such as Car-T in patients with ITP.

Effect of Helicobacter Pylori eradication on patients with ITP: a meta-analysis of studies conducted in the Middle East

Background

Immune thrombocytopenia (ITP) is a bleeding disorder. Helicobacter pylori is a Gram-negative bacterium that is presumed to be associated with ITP and therapeutic response of patients. To evaluate the effect of H. pylori eradication on platelet count of ITP patients, we analyzed the studies conducted on the association between H. pylori infection and response to therapy in ITP patients in Western Asia focusing on the Middle East region.

Methods

A systematic search of databases (PubMed/Medline, ISI Web of Science, Cochrane Central) and Google Scholar search engine results was conducted up until January 2020. The keywords included in the search were Helicobacter pylori and/or H. pylori, ITP and/or immune thrombocytopenia.

Results

Seven studies comprising a total of 228 H. pylori-infected patients (193 with successful eradication) were included in this study. The association between H. pylori eradication and ITP was expressed as odds ratios (OR) and 95% confidence intervals (CI). The findings showed that patients who received eradication treatment for H. pylori infection had significantly higher OR (OR, 8.83; 95% CI, 2.03‒38.35; P=0.004) than those in the non-eradicated group.

Conclusion

Our results indicate a significant therapeutic effect of H. pylori eradication on the platelet count of patients with chronic ITP. Given the inherent limitations of this study, including the small number of patients, further studies with more patients are recommended.