Characterization of envelope sequence of HIV virus in children infected with HIV in Vietnam.

BACKGROUND: HIV is characterized by high levels of genetic variability, including increased numbers of heterogeneous sequences of the envelope region. Therefore, studying genetic variability of HIV in relation to viral replication might facilitate prognosis of disease progression. METHODS: The study was designed as cross-sectional; data and samples of participants collected and analyzed env genes were obtained from 23 children enrolled by Vietnam National Children's Hospital. RESULTS: Substantial mutations in the C2 region were found in patients with high levels of viral replication while changes in the C3 region were mostly found in patients with low viral load. In the V1 region, we found profound amino acid modifications in patients with low HIV viral loads in contrast to the V2 sequence, where we identified single point mutations in patients with increased HIV viral load. The V3 region was relatively homogeneous, while profound deletions in the V4 region were detected in patients with increased viral replication. CONCLUSION: Our results suggest that genetic variations in different regions of the HIV envelope sequence, including both conserved C2 and C3 and variable V1/V2 and V4 regions, might be involved in increased viral infectivity and replication capacity. Such knowledge might help improve prediction of HIV progress and treatment in patients.

In Vitro Production of Cartilage Tissue from Rabbit Bone Marrow-Derived Mesenchymal Stem Cells and Polycaprolactone Scaffold.

In vitro production of tissues or tissue engineering is a promising approach to produce artificial tissues for regenerative medicine. There are at least three important components of tissue engineering, including stem cells, scaffolds and growth factors. This study aimed to produce cartilage tissues in vitro from culture and chondrogenic differentiation of rabbit bone marrow-derived mesenchymal stem cells (BMMSCs), induced by chondrogenesis medium, on biodegradable polycaprolactone (PCL) scaffolds. BMMSCs were isolated from rabbit bone marrow according to the standard protocol. The adherence, proliferation and differentiation of BMMSCs on scaffolds were investigated using two scaffold systems: PCL scaffolds and collagen-coated PCL (PCL/col) scaffolds. The results showed that BMMSCs could attach and grow on both PCL and PCL/col scaffolds. However, the adhesion efficacy of BMMSCs on the PCL/col scaffolds was significantly better than on PCL scaffolds. Under induced conditions, BMMSCs on PLC/col scaffolds showed increased aggrecan accumulation and upregulated expression of chondrogenesis-associated genes (e.g. collagen type II, collagen type I, aggrecan and collagen type X) after 3, 7, 21 and 28 days of induction. These in vitro cartilage tissues could form mature chondrocyte-like cells after they were grafted into rabbits. The results suggest that use of BMMSCs in combination with polycaprolactone scaffolds and chondrogenesis medium can be a way to form in vitro cartilage tissue.

Comparative Clinical Observation of Arthroscopic Microfracture in the Presence and Absence of a Stromal Vascular Fraction Injection for Osteoarthritis.

Osteoarthritis (OA) is a degenerative cartilage disease that is characterized by a local inflammatory reaction. Consequently, many studies have been performed to identify suitable prevention and treatment interventions. In recent years, both arthroscopic microfracture (AM) and stem cell therapy have been used clinically to treat OA. This study aimed to evaluate the clinical effects of AM in the presence and absence of a stromal vascular fraction (SVF) injection in the management of patients with OA. Thirty patients with grade 2 or 3 (Lawrence scale) OA of the knee participated in this study. Placebo group patients (n = 15) received AM alone; treatment group patients (n = 15) received AM and an adipose tissue-derived SVF injection. The SVF was suspended in platelet-rich plasma (PRP) before injection into the joint. Patient groups were monitored and scored with the Western Ontario and McMaster Universities Arthritis Index (WOMAC), Lysholm, Visual Analog Pain Scale (VAS), and modified Outerbridge classifications before treatment and at 6, 12, and 18 months post-treatment. Bone marrow edema was also assessed at these time points. Patients were evaluated for knee activity (joint motion amplitude) and adverse effects relating to surgery and stem cell injection. Treatment efficacy was significantly different between placebo and treatment groups. All treatment group patients had significantly reduced pain and WOMAC scores, and increased Lysholm and VAS scores compared with the placebo group. These findings suggest that the SVF/PRP injection efficiently improved OA for 18 months after treatment. This study will be continuously monitored for additional 24 months. Stem Cells Translational Medicine 2017;6:187-195.

Isolation and proliferation of umbilical cord tissue derived mesenchymal stem cells for clinical applications.

Umbilical cord (UC) is a rich source of rapidly proliferating mesenchymal stem cells (MSCs) that are easily cultured on a large-scale. Clinical applications of UC-MSCs include graft-versus-host disease, and diabetes mellitus types 1 and 2. UC-MSCs should be isolated and proliferated according to good manufacturing practice (GMP) with animal component-free medium, quality assurance, and quality control for their use in clinical applications. This study developed a GMP standard protocol for UC-MSC isolation and culture. UC blood and UC were collected from the same donors. Blood vasculature was removed from UC. UC blood was used as a source of activated platelet rich plasma (aPRP). Small fragments (1-2 mm(2)) of UC membrane and Wharton's jelly were cut and cultured in DMEM/F12 medium containing 1 % antibiotic-antimycotic, aPRP (2.5, 5, 7.5 and 10 %) at 37 °C in 5 % CO2. The MSC properties of UC-MSCs at passage 5 such as osteoblast, chondroblast and adipocyte differentiation, and markers including CD13, CD14, CD29, CD34, CD44, CD45, CD73, CD90, CD105, and HLA-DR were confirmed. UC-MSCs also were analyzed for karyotype, expression of tumorigenesis related genes, cell cycle, doubling time as well as in vivo tumor formation in NOD/SCID mice. Control cells consisted of UC-MSCs cultured in DMEM/F12 plus 1 % antibiotic-antimycotic, and 10 % fetal bovine serum (FBS). All UC-MSC (n = 30) samples were successfully cultured in medium containing 7.5 and 10 % aPRP, 92 % of samples grew in 5.0 % aPRP, 86 % of samples in 2.5 % aPRP, and 72 % grew in 10 % FBS. UC-MSCs in these four groups exhibited similar marker profiles. Moreover, the proliferation rates in medium with PRP, especially 7.5 and 10 %, were significantly quicker compared with 2.5 and 5 % aPRP or 10 % FBS. These cells maintained a normal karyotype for 15 sub-cultures, and differentiated into osteoblasts, chondroblasts, and adipocytes. The analysis of pluripotent cell markers showed UC-MSCs maintained the expression of the oncogenes Nanog and Oct4 after long term culture but failed to transfer tumors in NOD/SCID mice. Replacing FBS with aPRP in the culture medium for UC tissues allowed the successful isolation of UC-MSCs that satisfy the minimum standards for clinical applications.