Journal: Methods in molecular biology (Clifton, N.J.)

Article Title: Analysis of biomarkers of caloric restriction in aging cells

doi: 10.1007/978-1-62703-556-9_3

Figure Lengend Snippet: Cellular senescence is determined by the Senescence β-Galactosidase (SA-β-Gal) assay. Human WI-38 fibroblasts at a proliferating state (young, A) and senescence (old, B) are subjected to SA-β-Gal staining and photographed. Blue staining cells are SA-β-Gal-positive or senescent cells. Magnification, ×100.

Article Snippet: Phosphate-buffered saline (PBS) Senescence β-Galactosidase staining kit (Cell Signaling) 5-bromo-4-chloro-3-indolyl-beta-D-galactoside (X-Gal) (Sigma)

Techniques: Staining

Journal: Vaccine

Article Title: Enhanced elicitation of potent neutralizing antibodies by the SARS-CoV-2 spike receptor binding domain Fc fusion protein in mice

doi: 10.1016/j.vaccine.2020.09.058

Figure Lengend Snippet: Inhibition of cell-cell fusion (A) by mouse serum, correlation analysis for fusion inhibition assay with pseudo-nertralization (B) and competitive ELISA (C). (A) A β-galactosidase (β-Gal) reporter gene-based quantitative cell–cell fusion assay was used, in which T7 polymerase expressing 293T-S pre-incubated with mouse serum followed by mixing with T7 promotor controlled β-Gal expressing 293T-ACE2 cells. After 3 hrs incubation, the β-Gal activity was detected by a chromogenic reaction using the β-Gal substrate CPRG. Fusion inhibition percentage was plotted against serum dilution folds from which 50% fusion inhibition antibody titers (IC 50 ) was calculated in Graphpad Prism 7. Experiments were performed in duplicate and the error bars denote ± SD, n = 2. Statistical significance was defined as *: P < 0.05, n.s.: P > 0.05. (B) Correlation analysis between cell–cell fusion inhibition (IC 50 ) and pseudo-neutralization antibody titers (NT 50 ) for sera of day 13 and day 27. (C) Correlation analysis between cell–cell fusion inhibition (IC 50 ) and competitive ELISA (EC 50 ) for sera of day 13 and day 27. Correlation and linear regression analyses were performed in GraphPad Prism using Pearson’s correlation coefficients. Statistical significance was calculated using the two-tailed test. The dashed lines indicate the standard deviations of the linear regression plots.

Article Snippet: Then cells were then lysed, and the β-gal activity was measured using β-galactosidase assay kit (substrate CPRG, G-Biosciences, St. Louis, MO) following the manufacturer’s protocols.

Techniques: Inhibition, Competitive ELISA, Cell-Cell Fusion Assay, Expressing, Incubation, Activity Assay, Neutralization, Two Tailed Test