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In December 2022, the Omicron variant of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) became dominant in China due to its high infectivity and lower mortality rate. The risk of critical illness and mortality among patients with hematologic malignancies who contracted SARS-CoV-2 was particularly high. The aim of this study was to draft a consensus to facilitate effective treatments for these patients based on the type and severity of the disease. Following the outbreak of the novel coronavirus in China, a steering committee consisting of experienced hematologists was formed by the Specialized Committee of Oncology and Microecology of the Chinese Anti-Cancer Association. The expert group drafted a consensus on the management and intervention measures for different types of hematologic malignancies based on the clinical characteristics of the Omicron variant of the SARS-CoV-2 infection, along with relevant guidelines and literature. The expert group drafted independent recommendations on several important aspects based on the epidemiology of the Omicron variant in China and the unique vulnerability of patients with hematologic malignancies. These included prophylactic vaccinations for those with hematologic malignancies, the use of plasma from blood donors who recovered from the novel coronavirus infection, the establishment of negative pressure wards, the use of steady-state mobilization of peripheral blood hematopoietic stem cells, the provision of psychological support for patients and medical staff, and a focus on maintaining a healthy intestinal microecology., (Copyright © 2023 Copyright: © 2023 Journal of Cancer Research and Therapeutics.)

B cells play a central role in the pathogenesis of immune thrombocytopenia (ITP) by participating in humoral immunity. Meanwhile, regulatory B cells (Bregs), one subset of B cells, express negative regulatory effect on ITP. Mesenchymal stem cells (MSCs) have been demonstrated in the ability to induce immunosuppression, and stromal cell-derived factor-1 α (SDF-1 α ) plays an important role in the migration and survival of MSCs. To investigate the mechanism of SDF-1 α in controlling umbilical cord-derived MSCs (UC-MSCs) in inducing regulatory B cell differentiation of patients with ITP, we reconfirmed that SDF-1 α promotes the proliferation of MSCs at the low doses of 0.05  μ g/mL and 0.1  μ g/mL but inhibits the proliferation and promotes the apoptosis of UC-MSCs at the high doses 0.5  μ g/mL and 1  μ g/mL; when UC-MSCs are cocultured with SDF-1 α at 0.1  μ g/mL, the decreased proportion of CD19 + /CD24 hi /CD38 hi cells and IL-10-producing B cells (B 10 cell), considered as the Breg subset from ITP significantly enhanced, and the content of IL-10 in the supernatant is also obviously increased. The proportion of Bregs and the IL-10 secretion could be further promoted by the UC-MSCs treated with 0.1  μ g/mL SDF-1 α , which could also promote the miRNA-133 expression of UC-MSCs in an exosome-dependent manner; moreover, while the UC-MSCs were transfected with the miR-133 inhibitor, the proportion of induced Bregs decreased obviously when cocultured with peripheral blood mononuclear cells (PBMCs) of ITP. We conclude that UC-MSCs could effectively enhance the decreased proportion of Bregs from ITP; at appropriate concentrations, SDF-1 α may promote the proliferating and survival ability of UC-MSCs and improve the production of Bregs induced by UC-MSCs through controlling miRNA-133 expression in the exosomes., Competing Interests: The authors declare that they have no competing interests., (Copyright © 2021 Zhe Chen et al.)