Figure 1.

Comparative assessment of the TEAC values and hydrogel viscosity modulating properties of various doses of progenitor tenocyte whole cell samples (i.e., lyophilizates reconstituted in aqueous solvent), before and after submicron filtration and γ-irradiation, respectively. TEAC dose-response of reconstituted non-irradiated (A) or γ-irradiated (31 kGy, (B)) whole cell samples containing 1.5 to 7.5 million cell equivalents/vial before and after 0.22 µm filtration, with the corresponding placebo controls. Results notably outlined a strong response (i.e., relative increase) of the γ-irradiated samples in TEAC measurements compared respectively to the same non-irradiated samples ((B) vs. (A)). Complex viscosity η* of reconstituted (i.e., in a hydrogel of HA 2.2–2.4 MDa MW at 1% in H₂O:PBS 1:1) non-irradiated (C) or γ-irradiated (31 kGy, (D)) whole cell samples containing 1.5 to 7.5 million cell equivalents/vial, with the corresponding placebo controls. Each sample was analyzed following the addition of H₂O₂ (i.e., challenge item) or PBS (i.e., internal non-challenged controls) and incubation for 1 h at 37 °C. Very significant statistical differences (i.e., ** or 0.001 < p value < 0.01) or extremely significant statistical differences (i.e., *** or 0.0001 < p value < 0.001; **** or p value < 0.0001) were found between the presented mean values. HA, hyaluronic acid; kGy, kiloGray; LYO-WC, lyophilized whole cell fraction; MW, molecular weight; PBS, phosphate buffered saline; TEAC, Trolox equivalent antioxidant capacity.