Carboxymethyl cellulose in composite collagen gel improves mesenchymal stromal cell proliferation and migration.

Gels based on type I collagen have been actively studied over the past decades and are already used in regenerative medicine. The main limitation of using gels is the impossibility of long-term cell cultivation inside the gels due to their contraction under the influence of cells. Gels have the greatest regenerative potential after a long time of cells cultivation, since the cells synthesize extracellular matrix proteins and growth factors. In the contracting gels, cells cannot expand, resulting in deterioration of the beneficial functional properties of the gel. To increase the rigidity of the gel, we used carboxymethyl cellulose (CMC). However, there are no data in the literature on the analysis of the interaction of cells with such scaffolds. We formed composite gels based on 2 % type I collagen and 5 % CMC, which are superior to gels based on pure collagen. Spectrophotometry, FTIR and SEM techniques confirmed the preservation of the native structure of collagen fibril in the presence of CMC, while the rigidity and stability of the composite gel increased noticeably compared to pure collagen gel. For the first time, studies were conducted to evaluate the direct interaction of human cells with composite gels based on collagen and CMC.