Hemolytic complement activity in aqueous humor.

Hemolytic C1, C4, C3, and C5 and IgG levels were measured in aqueous humor obtained at surgery from human eyes without inflammation or previous surgery (group 1), eyes with previous surgery (group 2), and eyes with anterior uveitis (group 3). Serum hemolytic complement and IgG levels were also compared with aqueous humor levels. Aqueous humor from eyes in group 1 contained functional C1, C4, C3, and C5, but there was relatively little complement in normal aqueous humor when compared with serum. The mean values of all complement components and IgG in aqueous humor increased from groups 1 to 3; aqueous-serum ratios for each complement component and IgG also increased from groups 1 to 3. Eyes in group 3 had the highest complement and IgG levels and in some cases these values approached those found in serum.