CASIN and AMD3100 enhance endothelial cell proliferation, tube formation and sprouting.

Endothelial dysfunction is prominent in atherosclerosis, hypertension, diabetes, peripheral and cardiovascular diseases, and stroke. Novel therapeutic approaches to these conditions often involve development of tissue-engineered veins with ex vivo expanded endothelial cells. However, high cell number requirements limit these approaches to become applicable to clinical applications and highlight the requirement of technologies that accelerate expansion of vascular-forming cells. We have previously shown that novel small molecules could induce hematopoietic stem cell expansion ex vivo. We hypothesized that various small molecules targeting hematopoietic stem cell quiescence and mobilization could be used to induce endothelial cell expansion and angiogenesis due to common origin and shared characteristics of endothelial and hematopoietic cells. Here, we have screened thirty-five small molecules and found that CASIN and AMD3100 increase endothelial cell expansion up to two-fold and induce tube formation and ex vivo sprouting. In addition, we have studied how CASIN and AMD3100 affect cell migration, apoptosis and cell cycle of endothelial cells. CASIN and AMD3100 upregulate key endothelial marker genes and downregulate a number of cyclin dependent kinase inhibitors. These findings suggest that CASIN and AMD3100 could be further tested in the development of artificial vascular systems and vascular gene editing technologies. Furthermore, these findings may have potential to contribute to the development of alternative treatment methods for diseases that cause endothelial damage

Rapid Nanoplasmonic-Enhanced Detection of SARS-CoV-2 and Variants on DNA Aptamer Metasurfaces

Since the discovery of coronavirus disease 2019 (COVID-19) in December 2019, it has been mainly diagnosed with quantitative reverse transcription polymerase chain reaction (PCR) of nasal swabs in clinics. A very sensitive and rapid detection technique using easily collected fluids such as saliva is needed for safer and more practical, precise mass testing. Here, we introduce a computationally screened gold-nanopatterned metasurface platform out of a pattern space of 2100 combinations for strongly enhanced light–virus interaction using a genetic algorithm and apply them to investigate the presence and concentration of the severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2). In our approach, the gold metasurface with the nanopattern that provides the highest plasmonic enhancement is modified with the primary DNA aptamer for COVID-19 sensing from unprocessed saliva. A fluorescently tagged secondary aptamer was used to bind the virus that was then captured on the surface with the primary aptamer. By incorporating machine learning to identify the virus from Raman spectra, we achieved 95.2% sensitivity and specificity on 36 SARS-CoV-2 PCR-positive and 33 SARS-CoV-2 PCR-negative samples collected in the clinics. In addition, we demonstrated that our nanoplasmonic aptasensor could distinguish wild-type, Alpha, and Beta variants through the machine learning analysis of their spectra. Our results may help pave the way for effective, safe, and quantitative preventive screening and identification of variants

Effect of BTN162b2 and CoronaVac boosters on humoral and cellular immunity of individuals previously fully vaccinated with CoronaVac against SARS-CoV-2: A longitudinal study

Background It is essential to know about immune response levels after booster doses of the two different types of vaccines, mRNA, and the inactivated, currently used against COVID-19. For this purpose, we aimed to determine the effects of BNT162b2 (BNT) and CoronaVac (CV) boosters on the humoral and cellular immunity of individuals who had two doses of CV vaccination. Methods The study was conducted in three centers (Koc University Hospital, Istanbul University Cerrahpasa Hospital, and Istanbul University, Istanbul Medical School Hospital) in Istanbul, Turkey. Individuals who had been previously immunized with two doses of CV and no history of COVID-19 were included. The baseline blood samples were collected 3-5 months after the second dose of CV. Follow-up blood samples were taken 1 and 3 months after administration of third doses of CV, or one dose of BNT boosters. Neutralizing antibody titers were measured by plaque reduction assay. The CD4+ T cell, CD8+ T cell, effector CD4+CD38+CD69+ T cell, and effector CD8+CD38+CD69+ T cell ratios were determined by flow cytometry. The intracellular IFN-gamma and IL-2 responses were measured by ELISpot assay. Results We found a 3.38-fold increase in neutralizing antibody geometric mean titers (NA GMT, 78.69) 1 month after BNT booster and maintained at the third month (NA GMT, 80). Nevertheless, in the CV booster group, significantly lower NA GMT than BNT after 1 month and 3 months were observed (21.44 and 28.44, respectively) (p < .001). In the ELISpot assay, IL-2 levels after BNT were higher than baseline and CV booster (p < .001) while IFN-gamma levels were significantly higher than baseline (p < .001). The CD8+CD38+CD69+ and CD4+CD38+CD69+ T cells were stimulated predominantly in the third month of the BNT boosters. Conclusion The neutralizing antibody levels after 3 months of the BNT booster were higher than the antibody levels after CV in fully vaccinated individuals. On the contrary, ratio of the effector T cells increased along with greater IFN-gamma activation after BNT booster. By considering the waning immunity, we suggest a new booster dose with BNT for the countries that already had two doses of primary CV regimens