Opsonization avoidance

Microorganisms are more readily phagocytosed when coated with antibody (opsonized). This is due to the presence on the white blood cells of receptors for the Fc fragment ofIgM and IgG (discussed in Chapter 14). Avoidance of opsonization will clearly enhance the chances of survival of a particular pathogen. A substance called... 

It has long been known that the presence or absence of CPS correlates in many cases with disease and that bactericidal and opsonic antibodies directed against them protect the host from invasive disease caused by encapsulated bacteria [2]. Antibodies directed against the LPS play also a major role in protection against infection by avoiding bacterial colonization of specific mucosa or organ [3]. 

Antilymphocyte serum, ALS an immune serum with an opsonizing (see Opsonization) and cytotoxic effect on lymphocytes. It was used for immune suppression before Monoclonal antibodies (see) to specific classes of lymphocytes became widely available. The antibodies were raised in other species of animals by injection of human lymphocytes from blood, thymus, spleen or the thoracic duct. To avoid undesired side effects, the A.s. was purified and administered primarily as antilymphocyte globulin (ALG). Treatment with ALG affects mainly cellular immunity, particularly that provided by long-lived circulating lymphocytes. 

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