Effects of Rhazya Stricta plant organic extracts on human induced pluripotent stem cells derived neural stem cells.

Rhazya Stricta (R. stricta) has been employed as a natural remedy for several diseases for centuries. Numerous studies revealed that R. stricta extracts contain alkaloids, tannins, and flavonoids that possess antimicrobial, anticancer, antihypertensive, and antioxidant activities. In this study, we examined the effects of organic extracts from different parts of R. stricta plant on human pluripotent stem cells (hiPSCs)-derived neural stem cells (NSCs) for medical purposes. NSCs were incubated with different concentrations of organic extracts from the leaves, stem, and fruits, and we assessed the growth and viability of the cells by using MTS assay and the chemical composition of the potential plant extract by using gas chromatography-mass spectrometry (GC/MS). Our results revealed that the methanolic extract from the stem increased NSCs growth significantly, particularly at a concentration of 25 µg/ml. GC/MS analysis was utilized to identify the potential compounds of the methanolic extract. In conclusion, our results demonstrated for the first time that methanolic stem extract of R. stricta contains compounds that can positively impact NSCs growth. These compounds can be further investigated to determine the potential bioactive compounds that can be used for research and medical purposes.

Revisiting the Role of γδ T Cells in Anti-CMV Immune Response after Transplantation.

Gamma delta (γδ) T cells form an unconventional subset of T lymphocytes that express a T cell receptor (TCR) consisting of γ and δ chains. Unlike conventional αß T cells, γδ T cells share the immune signature of both the innate and the adaptive immunity. These features allow γδ T cells to act in front-line defense against infections and tumors, rendering them an attractive target for immunotherapy. The role of γδ T cells in the immune response to cytomegalovirus (CMV) has been the focus of intense research for several years, particularly in the context of transplantation, as CMV reactivation remains a major cause of transplant-related morbidity and mortality. Therefore, a better understanding of the mechanisms that underlie CMV immune responses could enable the design of novel γδ T cell-based therapeutic approaches. In this regard, the advent of next-generation sequencing (NGS) and single-cell TCR sequencing have allowed in-depth characterization of CMV-induced TCR repertoire changes. In this review, we try to shed light on recent findings addressing the adaptive role of γδ T cells in CMV immunosurveillance and revisit CMV-induced TCR reshaping in the era of NGS. Finally, we will demonstrate the favorable and unfavorable effects of CMV reactive γδ T cells post-transplantation.

In vitro induction of human embryonal carcinoma differentiation by a crude extract of Rhazya stricta.

BACKGROUND: Rhazya stricta Decne. is a medicinal plant that is widespread in Saudi Arabia and desert areas of the Arabian Peninsula. Its extract contains alkaloids, tannins, and flavonoids that are involved in different biological activities. The study aim was to evaluate the effects of Rhazya stricta plant extracts on the proliferation and differentiation of NTERA-2 (NT2) pluripotent embryonal carcinoma cells. METHODS: Soxhlet extraction was carried out using different solvents to extract stems, leaves and fruit parts of this plant. Cytotoxicity was evaluated by an MTS cell viability assay. The ability of the plant extract to induce cell differentiation was examined phenotypically using an inverted light microscope. The expression of pluripotency markers was investigated by reverse transcriptase polymerase chain reaction (RT-PCR) and immunocytochemistry. Phytochemical screening of chloroform stem extracts was carried out and a chromatographic fingerprint was generated using gas chromatography - mass spectrometry (GC-MS). RESULTS: Chloroform stem extract induced differentiation of NT2 cells at 5 µg/ml, and the differentiated cells exhibited neurite formation. Following induction of differentiation, there was significant down-regulation of the pluripotency marker genes Oct4 and Sox2. In addition, the surface antigen pluripotency marker, TRA-1-60, was strongly down-regulated. Phytochemical analysis of the extract showed the presence of alkaloids and saponins. The chromatogram revealed the presence of fifteen compounds with different retention times. CONCLUSION: Our results demonstrate for the first time that chloroform stem extract of R. stricta can induce neuronal differentiation of stem cells at an early stage and may contain potential therapeutic agent that can be used in neurodegenerative diseases.