The mechanism of entry into macrophage and intracellular trafficking varies based on the
opsonization status of the Brucella (Gorvel and Moreno, 2002).
Although fibronectins play a vital role in adhesion, migration, chemotaxis and
opsonization (19), many factors contribute to the local environment in a synergistic way.
sup][23] Activation of the complement system triggers apoptosis and
opsonization.
Patients without a spleen have an impaired phagocytosis and
opsonization, as well as decreased levels of immunoglobulins.
Several immune functions have been proposed for C-type lectins, including cell adhesion, glycoprotein turnover, activation of prophenoloxidase cascade, hemocyte-mediated nodule formation, encapsulation, and
opsonization (Zhang et al.
24) The Donath-Landsteiner antibody is an IgG class antibody that binds at low temperatures, where it fixes complement to the RBCs, then the cells are hemolyzed at warmer temperatures owing to the
opsonization with complement.
coli leads to internalization by macrophages by
opsonization.
The capsule is resistant to the activation of the alternative pathway of complement on its surface, thus avoiding
opsonization.
The major functions include activation of inflammation, activation of NK cells, removal of antigen-antibody complexes, and complement activation, with its pathogen
opsonization and membrane attack complex functions, among others.
SP-D is secreted as an acute phase reactant, especially in the presence of infectious agents; it plays a role in host defense mechanisms via adhesion to micro-organisms due to its hydrophilic nature (6, 7), is important in aggregation, neutralization, and
opsonization during phagocytosis, results in direct gram-negative bacterial cell-membrane lysis, inhibiting bacterial/fungal growth in macrophages, and has a aggregation-independent manner (7, 13).
Subsequent steps of the complement cascade lead to formation of several effector molecules, including
opsonization of pathogens, formation of the membrane attack complex inducing osmotic lysis of cells, and recruitment and activation of inflammatory cells by the anaphylatoxins complement C3a and C5a (25).
The bacterial capsule or slime layer effectively protects cells from
opsonization by antibodies, complement lysis, and phagocyte engulfment.
