Figure - PMC

Skip to main content

An official website of the United States government

Here's how you know

Here's how you know

Official websites use .gov
A .gov website belongs to an official government organization in the United States.

Secure .gov websites use HTTPS
A lock ( ) or https:// means you've safely connected to the .gov website. Share sensitive information only on official, secure websites.

View full-text article in PMC

. 2021 Feb 4;49(2):0300060520986049. doi: 10.1177/0300060520986049

Search in PMC
Search in PubMed
View in NLM Catalog
Add to search

© The Author(s) 2021

Creative Commons Non Commercial CC BY-NC: This article is distributed under the terms of the Creative Commons Attribution-NonCommercial 4.0 License (https://creativecommons.org/licenses/by-nc/4.0/) which permits non-commercial use, reproduction and distribution of the work without further permission provided the original work is attributed as specified on the SAGE and Open Access pages (https://us.sagepub.com/en-us/nam/open-access-at-sage).

PMC Copyright notice

Figure 3. — Effects of different cigarette smoke-media suspension (CSM) concentrations and stimulation times on type II alveolar epithelial cells (AECIIs). AECIIs were treated with different CSM concentrations (0%–20%) or treated with 10% CSE for different durations (0–48 hours). Senescence‑associated β‑galactosidase (SA-β-gal) activity was detected by staining. The cells were incubated with 4-methylumbelliferyl-β-D-galactopyranoside fluorogenic substrate at 37°C. Aliquots were removed from the reaction mixture over time (0–48 hours) and the fluorescence intensity of the hydrolysis product 4-methylumbellifer-one was measured. Readings were divided by the total protein per assay to correct for differences in extract concentration. SA-β-gal activity was increased in AECIIs with increasing CSM concentration and prolonged incubation time. Cells with blue-green staining indicated SA-β‑gal‑positive cells. Original magnification, ×200.

Figure 3. — Effects of different cigarette smoke-media suspension (CSM) concentrations and stimulation times on type II alveolar epithelial cells (AECIIs). AECIIs were treated with different CSM concentrations (0%–20%) or treated with 10% CSE for different durations (0–48 hours). Senescence‑associated β‑galactosidase (SA-β-gal) activity was detected by staining. The cells were incubated with 4-methylumbelliferyl-β-D-galactopyranoside fluorogenic substrate at 37°C. Aliquots were removed from the reaction mixture over time (0–48 hours) and the fluorescence intensity of the hydrolysis product 4-methylumbellifer-one was measured. Readings were divided by the total protein per assay to correct for differences in extract concentration. SA-β-gal activity was increased in AECIIs with increasing CSM concentration and prolonged incubation time. Cells with blue-green staining indicated SA-β‑gal‑positive cells. Original magnification, ×200.