The skin tissue of an African water mongoose (Atilax paludinosus) served as the original source of cells from which the A.P. Mongoose line was established by The Naval Biosciences Laboratory (NBL). Similar to other fibroblast lines, A.P. Mongoose cells are relatively easy to grow in culture dishes.

It is widely assumed among cell biologists that the fibroblast tendency to readily grow and proliferate in vitro is linked to their function in the body, where they are extremely important for wound healing. When tissue injury occurs, fibroblasts resident in connective tissue migrate to the affected area and proliferate under the less than optimal conditions, secreting significant amounts of procollagen and other proteins involved in the healing process. When not called upon to aid in tissue repair, fibroblasts exist as relatively solitary cells rather than in close association with other fibroblasts, a fact that some investigators have hypothesized may also be related to the ease of culturing the cells.

Fibroblasts are unspecialized cells that can undergo differentiation into a variety of mature cell types, including osteocytes, adipocytes, smooth muscle cells, and chondrocytes. Hormones, growth factors, and the extracellular matrix are all thought to influence fibroblast differentiation. Research has also suggested that fibroblasts found in different areas of the body may be inherently different and may be best suited for differentiating into certain kinds of cells. Cultured fibroblast lines established from dissimilar tissues frequently exhibit different characteristics. Fibroblasts derived from the skin, for example, are not typically able to be induced to differentiate as easily or as flexibly as fibroblasts derived from bone marrow.

The monolayer culture of African water mongoose cells illustrated above was fixed, permeabilized, blocked with 10-percent normal goat serum, and then treated with a cocktail of mouse anti-NPCP (nuclear pore complex protein) and rabbit anti-giantin (Golgi complex) primary antibodies followed by goat anti-mouse and anti-rabbit secondary antibodies (IgG) conjugated to Alexa Fluor 568 and Alexa Fluor 488, respectively. The filamentous actin network was counterstained with Alexa Fluor 350 conjugated to phalloidin. 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.

Triple Labeling of Mongoose Fibroblasts with MitoTracker Red CMXRos, Alexa Fluor 488, and Hoechst 33258 - Using a popular triple-fluorophore staining technique for mitochondria, filamentous actin, and the nucleus, the log phase monolayer culture of A.P. Mongoose cells illustrated in this section was first treated with MitoTracker Red CMXRos for one hour, and then fixed with medium containing 3.7-percent paraformaldehyde. After permeabilization and blocking with bovine serum albumen, the cells were labeled with Alexa Fluor 488 conjugated to phalloidin and counterstained with Hoechst 33258.

Histones and Peroxisomal Membrane Proteins in A.P. Mongoose Cells - In a double immunofluorescence experiment, the adherent monolayer culture of African water mongoose fibroblast cells presented in this section was fixed, permeabilized, blocked with 10 percent normal goat serum, and treated with a cocktail of mouse anti-histones (pan) and rabbit anti-PMP 70 primary antibodies, followed by goat anti-mouse and anti-rabbit secondary antibodies (IgG) conjugated to Texas Red and Alexa Fluor 488, respectively.

Visualizing the Mitochondrial and Actin Networks in Water Mongoose Fibroblasts - Applying a collection of popular mitochondrial, actin, and DNA probes, the featured culture of A.P. Mongoose cells was grown to log phase, treated with MitoTracker Red CMXRos before fixing, and then labeled with phalloidin and Hoechst 33258 after permeabilization. The red fluorescence arises from the mitochondrial dye (MitoTracker), while the phalloidin was conjugated to Alexa Fluor 488 to generate green fluorescence.

Focal Adhesion Distribution in A.P. Mongoose Cell Cultures - The adherent culture of A.P. Mongoose cells presented in this section was immunofluorescently labeled with anti-vinculin mouse monoclonal primary antibodies followed by goat anti-mouse IgG secondary antibodies conjugated to Texas Red. In addition, the specimen was simultaneously stained for DNA with the ultraviolet-absorbing probe Hoechst 33258, and for the cytoskeletal filamentous actin network with Alexa Fluor 488 conjugated to phalloidin.

Localizing the Tubulin and F-Actin Networks in African Water Mongoose Cells - Immunofluorescence was employed to label the microtubule network of a culture of A.P. Mongoose fibroblast cells with anti-tubulin mouse monoclonal primary antibodies followed by goat anti-mouse secondary antibodies conjugated to Alexa Fluor 568. The cells were also labeled for F-actin with Alexa Fluor 488 conjugated to phalloidin, and for cell nuclei with Hoechst 33342.

A.P. Mongoose Monolayer Cultures with MitoTracker Red CMXRos, Alexa Fluor 488, and Hoechst 33258 - The culture of water mongoose skin fibroblast cells that is presented in this section was labeled with MitoTracker Red CMXRos and Alexa Fluor 488 conjugated to phalloidin, which target mitochondria and filamentous actin, respectively. In addition, the cells were stained for nuclear DNA with Hoechst 33258.

Distribution of Vinculin and Filamentous Actin in Water Mongoose Cells - Focal adhesions were visualized in the featured log phase adherent monolayer culture of African water mongoose cells by immunofluorescent treatment with mouse anti-vinculin primary antibodies followed by goat anti-mouse Fab fragments conjugated to Texas Red. The actin cytoskeletal network was simultaneously imaged with Alexa Fluor 488 conjugated to phalloidin, and nuclei were counterstained with Hoechst 33258.

Targeting Giantin and Nuclear Pore Complex Proteins in A.P. Mongoose Cell Cultures - The proximity of the Golgi complex and nuclei in A.P. Mongoose cells was probed in a double immunofluorescence experiment with mouse anti-NPCP (nuclear pore complex protein) and rabbit anti-giantin primary antibodies. The antibody targets were visualized with goat secondary antibodies conjugated to Alexa Fluor 568 and Alexa Fluor 488, respectively, while the actin cytoskeletal framework was labeled with Alexa Fluor 350 conjugated to phalloidin.

Visualizing Focal Adhesions in Mongoose Fibroblast Cells - A culture of water mongoose fibroblast cells was immunofluorescently labeled with primary anti-vinculin mouse monoclonal antibodies followed by goat anti-mouse Fab fragments conjugated to Texas Red. Vinculin is a protein associated with the cytoplasmic face of focal adhesions.

Four Color Fluorescence with Synthetic Dyes and Antibodies in A.P. Mongoose Fibroblast Cells - The peroxisome organelles present in the African water mongoose cell culture presented in this section were immunofluorescently labeled with Alexa Fluor 750 conjugated to rabbit secondary antibody fragments directed against rabbit primary antibodies to peroxisomal membrane protein 70 (PMP 70), a major peroxisome membrane polypeptide. In addition, the culture was treated with Alexa Fluor 488 conjugated to phalloidin and MitoTracker Red CMXRos, targeting cytoskeletal F-actin and the mitochondrial network, respectively.

Distribution of Peroxisomes, Mitochondria, and Intermediate Filaments in Cultured APM Fibroblast Cells - Fibroblasts are able to give rise to a number of other cells types, including fat cells, bone cells, cartilage cells, and smooth muscle cells. Notably, all of the mature cells that fibroblasts may differentiate into are of mesodermal origin. An array of dynamic factors, such as hormones, growth factors, and the composition of the extracellular matrix, influence fibroblast differentiation. It also appears that the differentiation potential of fibroblasts varies based on location within the body and, when they are cultured, on their tissue of origin.