In situ production of innate immune cells in murine white adipose tissue

Immuno-metabolism and adipose tissue: The key role of hematopoietic stem cells

“…First, in the seminal study demonstrating BM-derived macrophage infiltration in WAT of obese mice, 15% of these macrophages did not derive from BM [7]. Second, it must be noted that although BM-HSC can reconstitute the WAT hematopoietic compartment in irradiated mice, they never reconstitute the entire immune compartment as in control animals [77]. Last, several arguments are in favor of the presence of hematopoietic progenitors in WAT.…”

“…More recently, we demonstrated that these HSC cells exhibit functional features of stem cells such as self-renewal and multipotency. In addition, these HSC present an antigen phenotype similar to medullar HSC, repopulate all the major hematopoietic lineages in long term reconstitution assays (even when injected in competition with BM-HSC), and differentiate very efficiently into Natural Killer and myeloid cells [77]. Thus, innate immune cells present in subcutaneous WAT may be renewed in situ, via WAT HSC differentiation (Fig.…”

Perivascular support of human hematopoietic stem/progenitor cells

“…We further investigated the expression of the same stromal cell markers in human adult adipose tissue, considered as an abundant source of MSCs and recently suggested to also be a reservoir of HSCs. 39 Nestin, CXCL12, and Lep-R were all expressed in cells immediately adjacent to VWF-positive endothelial cells ( For personal use only. on May 12, 2018.…”

Macrophage function in obesity-induced inflammation and insulin resistance

“…Interestingly, WAT contains a pool of c-Kit + /Lin − /Sca-1 + cells that share features of hematopoietic stem cells [10]. This population fails to populate bone marrow in non-irradiated mice, but is capable of replenishing the innate immune cell pool in adipose tissue [85]. ATMs might thus be regenerated in situ independent of the bone marrow.…”