Fibroblast Invasive Migration into Fibronectin/Fibrin Gels Requires a Previously Uncharacterized Dermatan Sulfate-CD44 Proteoglycan

Abstract

After tissue injury, fibroblast migration from the peri-wound collagenous stroma into the fibrin-laden wound is critical for granulation tissue formation and subsequent healing. Recently we found that fibroblast transmigration from a collagen matrix into a fibrin matrix required the presence of fibronectin. Several integrins-alpha 4 beta 1, alpha 5 beta 1, and alpha v beta 3-with known fibronectin binding affinity were necessary for this invasive migration. Here we examined another family of cell surface receptors: the proteoglycans. We found that dermatan sulfate was required for fibroblast migration into a fibronectin/fibrin gel. This conclusion was based on beta-xyloside inhibition of glycanation and specific glycosaminoglycan degradation. CD44, a cell surface receptor known to bind hyaluronan, not infrequently exists as a proteoglycan, decorated with various glycosaminoglycan chains including heparan sulfate and chondroitin sulfate, and as such can bind fibronectin. We found that CD44H, the non-spliced isoform of CD44, was necessary for fibroblast invasion into fibronectin/fibrin gels. Resting fibroblasts expressed mostly nonglycanated CD44H core protein, which became glycanated with chondroitin sulfate and dermatan sulfate, but not heparan sulfate, after a 24 h incubation with platelet-derived growth factor, the stimulus used in the migration assay. These results demonstrate that dermatan sulfate-CD44H proteoglycan is essential for fibroblast migration into fibrin clots and that platelet-derived growth factor, the stimulus for migration, induces the production of chondroitin-sulfate- and dermatan-sulfate-glycanated CD44H.

Hyaluronan-CD44-ERK1/2 Regulate Human Aortic Smooth Muscle Cell Motility during Aging

“…Therefore, increased ERK1/2 phosphorylation in aged AoSMCs combined with increased migration capacity likely depends on both augmented HA synthesis and higher expression of CD44 since treatment with HA oligosaccharide of 34-mer and the CD44 blocking antibody reduced both ERK1/2 phosphorylation and cell migration. Interestingly, the A3D8 anti CD44 antibody that did not block HA binding to CD44, inhibited cell migration in our model and in other models (12,51), probably by preventing CD44 conformation changes induced by HA binding. However, in other systems it did not affect migration (53).…”

Single-molecule binding of CD44 to fibrin versus P-selectin predicts their distinct shear-dependent interactions in cancer

“…Treatment of immunopurified CD44v with chondroitinase ABC, which degrades all forms of chondroitin sulfate (CS) and dermatan sulfate (DS) (Clark et al, 2004) essentially abolished the frequency of binding events between CD44v and fibrin at all contact durations (Fig. 8A), indicating the crucial roles of CS and/or DS in CD44v-fibrin molecular recognition.…”

Differential Use of Chondroitin Sulfate to Regulate Hyaluronan Binding by Receptor CD44 in Inflammatory and Interleukin 4-activated Macrophages

“…The induced changes in chondroitin sulfate seen after cytokine treatment are important in promoting CD44-mediated motility on these substrates. Platelet-derived growth factor induces invasive migration of human dermal fibroblasts into a fibronectin/fibrin gel that can be blocked by both ␤-D-xyloside and anti-CD44 mAbs (62), whereas ␤-Dxyloside also inhibits invasion of rabbit wound microvascular endothelial cells into a fibrin matrix (66). Similarly, the invasion and migration of mouse melanoma on type I collagen is increased after TGF-␤ treatment and blocked by ␤-Dxyloside (61).…”

“…Chondroitin sulfate chain length is also increased on CD44 in human lung fibroblasts (60) and mouse melanoma cells (61) upon TGF-␤ treatment, raising the possibility that this cytokine may reduce hyaluronan binding in some conditions. Platelet-derived growth factor also increases chondroitin sulfate addition to CD44 in human dermal fibroblasts (62) and can increase the ratio of 6-to 4-sulfation (57,59), although this has not been shown for CD44.…”