Scanning electron micrographs revealed marked variations in surface morphology and size of mononuclear phagocytes cultured for short (4 hour) and long (7-45 days) durations. Soon after isolation from blood, monocytes showed only a few filopodia but extensive ruffled membranes. During culture, they increased greatly in size as they matured into macrophages. The macrophage surface showed large numbers of microvillous projections and elongated radiating filopodia. Intercommunication of filopodia between adjacent cells was observed. Addition of Candida spores and latex particles allowed sequential photographic documentation of the phagocytic process. Filopodia attached to the particle and subsequently became confluent to form a continuous membrane which enveloped the particle and eventually interiorized it. When a maximum number of particles had been engulfed, the macrophages appeared bloated with only a thin membrane, devoid of cytoplasmic extensions, surrounding the ingested particles.
ASJC Scopus subject areas
- Molecular Biology