Follistatin-like protein 1 promotes arthritis by up-regulating IFN-gamma.

Follistatin-like protein-1 (FSTL-1) is a poorly characterized protein that is up-regulated in the early stage of collagen-induced arthritis and that exacerbates arthritis when delivered by gene transfer. The current study was designed to determine the mechanism by which FSTL-1 promotes arthritis. FSTL-1 was injected into mouse paws, resulting in severe paw swelling associated with up-regulation of IFN-gamma transcript and the IFN-gamma-induced chemokine, CXCL10.

Chemotherapy disrupts activity of translational regulatory proteins in bone marrow stromal cells.

Objective: Bone marrow stromal cell function is a critical influence on hematopoietic reconstitution following progenitor or stem cell transplantation. Stromal cells support hematopoietic cell migration, survival, and proliferation. We have previously reported that stromal cell matrix metalloproteinase-2 (MMP-2) is necessary for optimal support of pro-B-cell chemotaxis through its regulation of stromal cell-derived factor-1 (CXCL12) release.

MMP-2 is required for bone marrow stromal cell support of pro-B-cell chemotaxis.

Objective: We have previously demonstrated that bone marrow stromal cells (BMSCs) exposed to etoposide (VP-16) have reduced support of CXCR4(+) cell chemotaxis and diminished stromal cell derived factor-1 (CXCL12) in the supernatants. Based on the identification of CXCL12 as a matrix metalloproteinase-2 (MMP-2) substrate, we investigated potential dysregulation of MMP-2 expression or activity in chemotherapy-treated BMSCs.

Methods: BMSCs exposed to VP-16 were evaluated for MMP-2 expression by gelatin zymography, ELISA, and western blot.