Related Experiment Videos
Hamster peritoneal macrophages in vitro: substratum adhesion, spreading, phagocytosis and phagolysosome formation
Abstract:
A series of manipulations designed to promote cell adhesion and spreading made it possible to maintain satisfactorily hamster peritoneal macrophages in vitro for up to 30 days. The essential requirements for this include in vivo stimulation of the peritoneal cavity, coating of the substratum with polylysine, and the use of HEPES-buffered medium 199 supplemented with horse serum (10%), fetal bovine serum (10%), and lactalbumin hydrolysate (0.5%). Results with the single deletion of the medium components indicate that serum factors are essential for optimal spreading, and horse serum and lactalbumin hydrolysate for the adhesion of in vivo stimulated macrophages on coated glass surface. The thorotrast-labeling method revealed that secondary lysosomes are especially numerous in cultured cells, which otherwise resemble mouse macrophages in cellular organization, as shown by scanning and transmission electron microscopy. More than 95% of the cultured cells manifested cytochalasin B-sensitive phagocytosis of polystyrene latex spheres which, along with morphologic and ultrastructural evidence, indicate the homogeneity of cell population. Erythrophagocytosis of hamster macrophages was demonstrated by scanning electron microscopy and found higher after opsonization implying the presence of receptors for immune ligands on their cell surface.
Insights
Hamster peritoneal macrophages can be cultured in vitro for 30 days using specific conditions. These conditions involve in vivo stimulation, polylysine-coated surfaces, and supplemented medium, enabling cell adhesion and spreading.
Area of Science:
- Immunology
- Cell Biology
- In Vitro Cultivation
Background:
- Maintaining primary immune cells like macrophages in vitro is crucial for research.
- Previous methods had limitations in long-term culture and functional assessment of macrophages.
Purpose of the Study:
- To establish a reliable method for long-term in vitro culture of hamster peritoneal macrophages.
- To characterize the morphology, ultrastructure, and phagocytic capabilities of cultured macrophages.
Main Methods:
- Hamster peritoneal macrophages were cultured in vitro using polylysine-coated surfaces and supplemented medium (Medium 199 with horse serum, fetal bovine serum, and lactalbumin hydrolysate).
- Cell adhesion, spreading, morphology, and phagocytosis (latex spheres, erythrocytes) were assessed using light and electron microscopy (SEM, TEM) and cytochalasin B treatment.
- Lysosomal content was evaluated using thorotrast labeling.
Main Results:
- A protocol was developed enabling hamster peritoneal macrophages to be maintained in vitro for up to 30 days with satisfactory adhesion and spreading.
- Serum factors were essential for optimal spreading, while horse serum and lactalbumin hydrolysate were critical for adhesion.
- Cultured cells exhibited numerous secondary lysosomes, similar cellular organization to mouse macrophages, and >95% phagocytic activity for latex spheres.
- Erythrophagocytosis was observed and increased after opsonization, indicating functional immune receptors.
Conclusions:
- A robust method for long-term in vitro culture of hamster peritoneal macrophages was established.
- The cultured macrophages retain key functional characteristics, including phagocytosis and expression of immune receptors.
- This model system is suitable for studying macrophage biology and function.