[Wip1 Phosphatase Regulates Hematopoietic Function in Mouse Spleen]

To investigate the regulatory effect of Wip1 phosphatase on hematopoietic function in the mouse spleen.

Wip1 knockout mice were bred, and the effect of Wip1 deletion on the proportion and number of hematopoietic stem/progenitor cells, as well as their mature subsets in mouse spleen was detected by flow cytometry. The Proteome Profiler^TM antibody array was used to analyze the role of Wip1 deletion on the expression of inflammatory cytokines in CD45^highCD11b⁺ myeloid cells sorted from mouse spleen.

Wip1 deletion resulted in smaller size and significant reduction of cell number in the mouse spleen. The absolute numbers of hematopoietic stem/progenitor cells were decreased. Meanwhile, the absolute number of T and B lymphocytes also significantly declined. However, the proportion of erythroid progenitors and erythroid cells at various stage significantly increased, but the number of mature erythroid cells decreased. Furthermore, the myeloid cells and their subsets neutrophils, monocytes, CD45^highCD11b⁺ and CD45^lowCD11b⁺ were all reduced. CD45^highCD11b⁺ myeloid cells displayed proinflammatory phenotype in the spleen.

Wip1 gene deletion impairs normal hematopoietic function in the mouse spleen, leading to a significant reduction of mature hematopoietic cells of various lineages, and proinflammatory phenotype in CD45^highCD11b⁺ myeloid cells.