The A-549 cell line was established in the early 1970s from the tissue of a human lung carcinoma excised from a 58-year old Caucasian male. The epithelial cells stain positive for keratin and are negative for reverse transcriptase.

Though utilized in a wide array of research, A-549 cells have been especially employed in studies of viral infections associated with asthma, asbestos-related tissue damage, emphysema, and other respiratory problems. Investigations carried out by M. Lieber and associates indicate that the cells synthesize lecithin with a high proportion of desaturated fatty acids via the cytidine diphosphocholine pathway.

A carcinoma is a form of cancer that characteristically initiates in the cells of epithelial tissues. Accordingly, the growths may develop in the lining of most any organ, including the skin. The most typical sites of carcinoma growth vary by country, but in the United States, the lungs, skin, stomach, uterus, ovaries, and prostate are among the most common. Currently carcinoma of the lung, which was once a relatively rare disease, is the most frequently diagnosed form of major cancer in the world and the cause of the most number of cancer-related deaths. The increased popularity of cigarette smoking during the twentieth century has been closely linked with the rise in the number of lung carcinoma cases.

The adherent log phase culture of human carcinoma cells illustrated above was treated for one hour with MitoTracker Red CMXRos in order to label the mitochondrial network, and the fixed cells were then incubated with mouse anti-cytokeratin primary antibodies followed by goat anti-mouse secondary antibodies (IgG) conjugated to Cy2. The nuclei were counterstained with Hoechst 33258. Images were recorded in grayscale with a 12-bit digital camera coupled to either a Nikon E-600 or Eclipse 80i microscope equipped with bandpass emission fluorescence filter optical blocks. During the processing stage, individual image channels were pseudocolored with RGB values corresponding to each of the fluorophore emission spectral profiles.

Cytokeratin Intermediate Filaments in Human Lung Carcinoma Cells - The A-549 cell culture presented in this section was immunofluorescently labeled with primary anti-cytokeratin (an intermediate filament protein) mouse monoclonal antibodies followed by goat anti-mouse Fab fragments conjugated to Marina Blue. MitoTracker Red CMXRos (mitochondria) and SYTOX Green (nuclei) were also used to counterstain the carcinoma cell culture.

A-549 Cells with Alexa Fluor 488, MitoTracker Red CMXRos, and Hoechst 33342 - The technique of immunofluorescence was utilized to label the featured culture of human lung carcinoma cells with primary anti-cytokeratin (pan) mouse monoclonal antibodies. Goat anti-mouse secondary antibody fragments conjugated to Alexa Fluor 488 were employed to visualize the antibody targets. In addition, the specimen was treated with MitoTracker Red CMXRos and Hoechst 33342 to stain the mitochondrial network and nuclei.

Labeling Carcinoma Cell Cultures with Immunofluorescence - A culture of A-549 carcinoma cells was immunofluorescently labeled with primary anti-cytokeratin mouse monoclonal antibodies followed by goat anti-mouse Fab fragments conjugated to Marina Blue. Mitochondria and nuclear DNA were targeted with MitoTracker Red CMXRos and SYTOX Green, respectively.

Mitochondria and Cytokeratin Distribution in A-549 Lung Carcinoma Cells - In order to visualize the relationship between mitochondria and the cytokeratin intermediate filament network, the culture of human lung carcinoma (A-549) cells presented in this section was immunofluorescently labeled with primary anti-cytokeratin (pan) mouse monoclonal antibodies followed by goat anti-mouse secondary antibody fragments conjugated to Marina Blue.