Mucous on wet epithelium prevents binding of pathogens or toxins to host cells. Cilia on epithelial cells act to block contact between host and parasite. Smooth muscle contraction pushes pathogens out of the host. Salivary mucins are high mw glycoproteins that form a barrier to penetration, concentrate IgA, and aggregate bacteria. Lactoferrins have antibacterial activity through iron binding, direct interaction with bacteria, generation of -OH radicals.
Complement mediates opsonization, chemotaxis, and membrane attack.
Acute phase reactants are mediators of inflammation. In the cell cytoplasm, endocytic vesicles fuse with primary lysosomes which contain proteases, nucleases, lipases and other hydrolytic enzymes. The products of this fusion are referred to as secondary lysosomes. Antigens are degraded in secondary lysosomes. Inflammation Inflammation is a non-specific reaction that occurs as a result of local tissue damage and the presence of foreign substances.