RESUMEN
The fifth wave of COVID-19, driven by the Omicron variant, started to surge in Hong Kong in December 2021. Previous studies have shown that younger adults, compared to older adults, are vulnerable to increased risks of side effects after vaccination. However, little is known about the COVID-19 vaccination behavior among younger adults, especially university students, in Hong Kong. Therefore, the present online survey study aimed to investigate the predictors of COVID-19 vaccination intention among university students in Hong Kong using the Health Belief Model (HBM) as a framework. Two other potential predictors, the previous influenza vaccine uptake frequency and the Hong Kong SAR government vaccination lottery program, were also examined. The intention to receive another dose of the COVID-19 vaccine was low (36.4%). Multivariate binomial logistic regression analysis showed that, after controlling for demographic and baseline characteristics, the perceived susceptibility (OR = 2.98, CI = 1.18-7.53) and previous influenza vaccine uptake frequency (OR = 1.54, CI = 1.08-2.19) significantly and positively predicted the COVID-19 vaccination intention. However, the government vaccination lottery program (i.e., wining prizes for being vaccinated) (OR = 0.87, CI = 0.34-2.26) was not a significant motivator of COVID-19 vaccination. Future public health campaigns should focus on the individual susceptibility to COVID-19 and past influenza vaccination history to promote increased vaccination uptake among university students.
RESUMEN
One of the major hurdles in intravenous regenerative cell therapy is the low homing efficiency to the area where these cells are needed. To increase cell homing toward areas of myocardial damage, we developed a bispecific tandem single-chain antibody (Tand-scFvSca-1+GPIIb/IIIa) that binds with high affinity to activated platelets via the activated glycoprotein (GP)IIb/IIIa receptor, and to a subset of peripheral blood mononuclear cells (PBMC) which express the stem cell antigen-1 (Sca-1) receptor. Methods: The Tand-scFvSca-1+GPIIb/IIIa was engineered, characterized and tested in a mouse model of ischemia-reperfusion (IR) injury applying left coronary artery occlusion for 60 min. Fluorescence cell tracking, cell infiltration studies, echocardiographic and histological analyses were performed. Results: Treatment of mice undergoing myocardial infarction with targeted-PBMCs led to successful cell delivery to the ischemic-reperfused myocardium, followed by a significant decrease in infiltration of inflammatory cells. Homing of targeted-PBMCs as shown by fluorescence cell tracking ultimately decreased fibrosis, increased capillary density, and restored cardiac function 4 weeks after ischemia-reperfusion injury. Conclusion: Tand-scFvSca-1+GPIIb/IIIa is a promising candidate to enhance therapeutic cell delivery in order to promote myocardial regeneration and thereby preventing heart failure.
