Deficiencies of C3 and Factor B as well as the inhibitors Factors H and I lead to chronic infection. Lack of the inhibitors results in the exhaustion of the supply of C3 causing functional deficiency of C3. Without C3 both the lytic pathway and much more importantly, opsonization are not optimally functioning. Lack of C6 results in very few effects other that the inability to eliminate encapsulated bacterial infections (e.g. Neisseria spp). The rare genetic deficiency of C1 esterase inhibitor (an enzyme which controls the functioning of C1 esterase) results in hereditary angiodæma. Lack of this enzyme causes inappropriate activation of C2 and the production of large quantities of C2a (also known as C2 kinin). This is a potent inducer of inflammation and of vasodilatation. The vasodilatation results in the oedema. | Deficiencies of C3 and Factor B as well as the inhibitors Factors H and I lead to chronic infection. Lack of the inhibitors results in the exhaustion of the supply of C3 causing functional deficiency of C3. Without C3 both the lytic pathway and much more importantly, opsonization are not optimally functioning. Lack of C6 results in very few effects other that the inability to eliminate encapsulated bacterial infections (e.g. Neisseria spp). The rare genetic deficiency of C1 esterase inhibitor (an enzyme which controls the functioning of C1 esterase) results in hereditary angiodæma. Lack of this enzyme causes inappropriate activation of C2 and the production of large quantities of C2a (also known as C2 kinin). This is a potent inducer of inflammation and of vasodilatation. The vasodilatation results in the oedema. |