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Purpose To evaluate the time required for colonies to develop from concentrated bone marrow aspirate (cBMA) and subacromial bursal tissue samples. Methods Samples of cBMA and subacromial bursa tissue were harvested from patients undergoing rotator cuff repair surgery between November 2014 and December 2019. Samples were analyzed for time to form colonies and number of colonies formed. The impact of age, sex, and cellularity (cBMA only) was analyzed. Samples were cultured and evaluated daily for colony formation in accordance with the guidelines of the International Society for Cellular Therapy. Demographic factors were analyzed for impact on time to form colonies and number of colonies formed. Results Samples of cBMA were obtained from 92 patients. Subacromial bursa tissue was obtained from 54 patients. For cBMA, older age was associated with more days to form colonies ( P = .003), but sex ( P = .955) and cellularity ( P = .623) were not. For bursa, increased age was associated with longer time to form colonies ( P = .002) but not sex ( P = .804). Conclusions : Increased age (in cBMA and subacromial bursa tissue) and lower initial cellularity (in cBMA) are associated with longer time to form colonies in culture. Clinical Relevance Although connective tissue progenitor cells are widely used in orthopaedic practice, there are few metrics to determine their efficacy. Time to form colonies may serve as an important measurement for determining connective tissue progenitor cell viability for augmentation of rotator cuff repair. Subacromial bursa tissue may represent a viable alternative to cBMA for augmentation of rotator cuff repair, capable of forming colonies expediently in vivo.

Purpose To evaluate the effect of a one-time dose of insulin or insulin-like growth factor 1 (IGF-1) on cellular proliferation and migration of subacromial bursa tissue (SBT) over time. Methods SBT was harvested from over the rotator cuff tendon in 4 consecutive patients undergoing primary arthroscopic rotator cuff repair. SBT was cultured for 3 weeks in complete media until reaching confluence. The culture dishes were stored in a humidified, low oxygen tension (5% CO 2 ) incubator at 37°C. SBT of each patient underwent treatment with a one-time dose of insulin or IGF-1, whereas nontreated SBT served as a negative control. Cellular proliferation and migration were evaluated after 24, 48, 72, and 96 hours of incubation. SBT-derived cells migrated in the detection field were visualized using fluorescent microscopy. Results Cellular proliferation at 24, 48, 72, and 96 hours was 1.40 ± 0.27, 1.00 ± 0.20, 1.47 ± 0.31, and 1.68 ± 0.28 for IGF-1; 1.44 ± 0.24, 1.15 ± 0.27, 1.60 ± 0.36, and 1.61 ± 0.32 for insulin; and 1.51 ± 0.35, 1.29 ± 0.33, 1.53 ± 0.35, and 1.57 ± 0.38 for nontreated SBT. Untreated SBT demonstrated a significantly greater proliferation when compared with IGF-1 and insulin within the first 48 hours, although this effect was found to subside by 96 hours. Cellular migration at 24, 48, 72, and 96 hours was 575.7 ± 45.0, 641.6 ± 77.7, 728.3 ± 122.9, and 752.3 ± 114.5 for IGF-1; 528.4 ± 31.3, 592.5 ± 69.8, 664.2 ± 115.2, and 695.6 ± 148.2 for insulin; and 524.4 ± 41.9, 564.4 ± 49.8, 653.2 ± 81.5, and 685.7 ± 115.5 for nontreated SBT. Insulin showed no difference in migration at each timepoint compared to nontreated SBT ( P > .05, respectively). Conclusions Insulin and IGF-1 initially inhibit cellular proliferation of human SBT, although this effect was found to subside by 96 hours. Further, neither insulin nor IGF-1 changed the slope of cellular migration over time. However, each treatment group demonstrated a significant increase in cellular proliferation and migration. Clinical Relevance In the setting of biologic augmentation of rotator cuff repair, the compatibility and synergistic effect of insulin on human SBT is highly limited.

Mongrel dogs, weighing 12 to 25 TCg., were anesthetized with Dial (6 nig./Kg.). The trachea WHS intubated, and appropriate femoral, jugular, and carotid vessels were isolated and eannnlnted as required. Heparin (3.5 mg./Kg.) was administered intravenously. When a change in blond volume was desired, blood (20 cc./Kg.) was withdrawn from, and reinfused into, the femoral artery via a, polyethylene cannula and a pressurized inverted flask containing heparin. Dextrnn was used to replenish blood lost through operative procedures. To modify myocardial contractility, tnetaraininol (Aramine) was infused in 0.9 per cent saline solution via one femoral vein in a mounts sufficient to raise the systolic blood pressure about 20 mm. ITg. Anoxia (with hypercapnia.) was induced by suppressing respiration with added anesthesia. When abrupt changes of cardiac output were desired, arteriovenous fistulae, created by placing large-bore cannulae in adjacent iliac veins and arteries and connecting the ends of the cannulae with plastic tubing, were opened or closed. PRESSURE MEASUREMENTSThe left ventricle was eannulated rctrogradely through the carotid artery and aortic, valve. A con-16. SARNOFF, S.