Characterization of poly(L-glutamic acid)-grafted hyaluronan as a novel candidate medicine and biomedical device for intra-articular injection

Reduced inflammation following human endometrial stromal/stem cell injection into male Wistar rats with cisplatin-induced acute kidney injury

Introduction: Inflammation is one of the most important mechanisms involved in cisplatin-induced acute kidney injury (AKI). Mesenchymal stromal/stem cells (MSCs) exhibit anti-inflammatory and immunomodulatory abilities. Human endometrial stromal/stem cells (hEnSCs) exhibit similar properties to MSCs. These cells secrete immunoregulators, so we investigated the inflammatory aspect of hEnSCs in the treatment of cisplatin-induced AKI in Wistar rats.

Methods: Each group consisted of 6 male Wistar rats. Groups were as follows: sham, model (5 mg/kg cisplatin, IP), and treatment (1 million hEnSCs, IV, 3 hours after cisplatin). Renal function, histopathology, proliferation rate, infiltration of CD3⁺ T cell, and expression of Il-10 and cystatin c (Cst3) were assessed on day 5. DiI-labeled cells were tracked in kidney and liver on days 4 and 14.

Results: HEnSC transplantation improved cisplatin-induced injuries such as renal dysfunction and tissue damage. The highest levels of pathologic scores and hyaline cast formation were observed in the model group while hEnSCs transplantation resulted in their reduction (154.00 ± 14.95, 8.00 ± 1.41 vs. 119.40 ± 5.43, 2.50 ± 1.05). The percentage of Ki-67 positive cells in the treatment group increased while cisplatin decreased proliferation (39.91 ± 5.33 vs. 23.91 ± 3.57 in glomeruli and 39.07 ± 2.95 vs. 16.61 ± 3.25 in tubules). The expression of Cst3 and Il-10 was higher in the model and treatment groups, respectively. DiI-labeled cells were observed in the renal tubules and liver lobes on days 4 and 14.

Conclusion: HEnSCs may ameliorate cisplatin-induced AKI through anti-inflammatory and immunomodulatory effects and/or through paracrine effects.

Hyaluronic acid bioinspired polymers for the regulation of cell chondrogenic and osteogenic differentiation

As the simplest glycosaminoglycan (GAG) in extracellular matrix, hyaluronic acid (HA) takes part in several important biological processes, such as regulating cell proliferation, differentiation, and migration. In this work, a series of HA-inspired polymers with different saccharide and carboxylate units (HA-analogue polymers) are synthesized by free radical polymerization, and characterized using Fourier transform infrared spectroscopy (FT-IR), gel permeation chromatography (GPC) and nuclear magnetic resonance spectrometer (NMR), Moreover, cell experiments demonstrate that HA-analogue polymers with a certain proportion of saccharide and carboxylate (PM₁G₁) units shows a positive effect on the proliferation and differentiation of bone marrow mesenchymal stem cells (BMSCs). Furthermore, HA-analogue polymers have prominent cartilage inductive capacity in chondrogenic induction medium (CIM) and brilliant bone inductive capacity in osteogenic induction medium (OIM) toward BMSCs. Therefore, it is confirmed that the HA-analogue polymers can effectively mimic the functions of HA and have broad potential application prospects in the biomedical and clinical fields.

Utility of a rotation/revolution-type agitator for chondrocyte isolation during preparation of engineered cartilage

During the manufacture of cell- and tissue-based products, such as engineered cartilage for autologous chondrocyte implantation, maximizing the number of cells isolated from donor tissue substantially improves the productivity of these products. The method used for agitating tissues with digestive fluid and enzymes can considerably affect both the quality and quantity of isolated cells. This study aimed to investigate the effectiveness of a rotation/revolution-type agitator for chondrocyte isolation following the enzymatic digestion of rat costal cartilage. Cartilage tissue cut into 1 mm³-thick sections was equally divided between two groups and placed in 50-mL conical tubes; sections in both groups were digested using 0.1 mg/mL liberase TH (collagenase/thermolysin) at 37 °C for 4 h with either rotation/revolution or conventional orbital agitation method. Compared with using conventional orbital agitator, using the rotation/revolution-type agitator resulted in a significant (>two-fold) increase in the number of isolated cells. In subsequent primary cultures, chondrocytes obtained by rotation/revolution agitation showed superior initial attachment to tissue culture dish on day 1 and 2 compared with those obtained by conventional agitation; however, no differences in cell proliferation or cartilage-related molecule expression patterns were observed between cells derived from either method after 3 days of subculture. These findings suggested that there are no disadvantages to the proposed rotation/revolution agitation method. Rotation/revolution-type agitators are a promising apparatus for preparing chondrocytes for primary cultures and cartilage tissue engineering.