Humoral Immune Responses Coagulation of Insect Haemolymph

The insect body cavity (haemocoel) contains haemolymph, which is analogous to vertebrate blood. Haemolymph transports nutrients, waste products, AMPs and signal molecules, and immune cells around the body. The haemolymph is also capable of coagulating or clotting upon contact with an invading microbe or upon physical injury. There are two clotting mechanisms, which occur in insects. The first method involves the clottable proteins, lipophorins, and the vitellogenein-like proteins (Theopold et al., 2002). The second mechanism involves a haemocyte-derived clotting cascade where clottable proteins are released from the cytoplasmic l-granules of the haemocytes into the haemolymph in response to activation by cell wall components of invading microbes. Gram-negative bacteria activate factor C while fungi activate factor G, resulting in conformational changes in these two proteins (Sritunyalucksana & Soderhall, 2000) and subsequent cleavage of factor B by a serine protease. This leads to the cleavage of pro-clotting enzyme (PCE). This enzyme catalyses the cleavage of a soluble protein, coagulogen into an insoluble aggregate, coagulin forming a viscous clot that traps invading microbes (Gorman & Paskewitz, 2001).

Cure Your Yeast Infection For Good

Cure Your Yeast Infection For Good

The term vaginitis is one that is applied to any inflammation or infection of the vagina, and there are many different conditions that are categorized together under this ‘broad’ heading, including bacterial vaginosis, trichomoniasis and non-infectious vaginitis.

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