1.Monitoring α-synuclein Aggregation Induced by Preformed α-synuclein Fibrils in an In Vitro Model System
Beom Jin KIM ; Hye Rin NOH ; Hyongjun JEON ; Sang Myun PARK
Experimental Neurobiology 2023;32(3):147-156
Parkinson’s disease (PD) is characterized by the presence of α-synuclein (α-syn) inclusions in the brain and the degeneration of dopamine-producing neurons. There is evidence to suggest that the progression of PD may be due to the prion-like spread of α-syn aggregates, so understanding and limiting α-syn propagation is a key area of research for developing PD treatments. Several cellular and animal model systems have been established to monitor α-syn aggregation and propagation. In this study, we developed an in vitro model using A53T α-syn-EGFP overexpressing SH-SY5Y cells and validated its usefulness for high-throughput screening of potential therapeutic targets. Treatment with preformed recombinant α-syn fibrils induced the formation of aggregation puncta of A53T α-syn-EGFP in these cells, which were analyzed using four indices: number of dots per cell, size of dots, intensity of dots, and percentage of cells containing aggregation puncta. Four indices are reliable indicators of the effectiveness of interventions against α-syn propagation in a one-day treatment model to minimize the screening time. This simple and efficient in vitro model system can be used for high-throughput screening to discover new targets for inhibiting α-syn propagation.
2.Relative Effectiveness of COVID-19 Vaccination in Healthcare Workers:3-Dose Versus 2-Dose Vaccination
Sung Ran KIM ; Hyeon Jeong KANG ; Hye Rin JEONG ; Su Yeon JANG ; Jae Eun LEE ; Da Eun KIM ; Hae Ry LEE ; Min Hee CHO ; Ji Yun NOH ; Hee Jin CHEONG ; Woo Joo KIM ; Joon Young SONG
Journal of Korean Medical Science 2022;37(35):e267-
The omicron variant of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) is known to have high infectivity and is more likely to evade vaccine immunity. However, booster vaccination is expected to strengthen cross-reactive immunity, thereby increasing the vaccine effectiveness (VE). This study aimed to evaluate the relative VE of the 3-dose (booster) vaccination compared with the 2-dose primary series vaccination in healthcare workers during omicron variant-dominant periods. During the omicron-dominant period from February 1, 2022 to February 28, 2022, a 1:1 matched case-control study was conducted.Healthcare workers with positive SARS-CoV-2 test results were classified as positive cases, whereas those with negative results served as controls. Compared with the 2-dose primary series vaccination, booster vaccination with mRNA vaccine showed moderate VE (53.1%).However, in multivariate analysis including the time elapsed after vaccination, the significant VE disappeared, reflecting the impact of recent vaccination rather than the third dose itself.