LOCAL PRODUCTION OF IGG AND IGG SUBCLASSES IN THE AQUEOUS-HUMOR OF PATIENTS WITH FUCHS HETEROCHROMIC CYCLITIS, HERPETIC UVEITIS AND TOXOPLASMIC CHORIORETINITIS

Changes in local immunity are important when considering the physiopat hology of uveitis. The aim of this study was to measure IgG and IgG su bclass concentrations in the serum and the AH of patients with three d ifferent types of uveitis and to determine for each of them the presen ce of a local production of IgG in the intra-ocular compartment. This investigation was extended to IgG subclasses. Serum and AH of 46 patie nts, including 11 with Fuchs heterochromic cyclitis (FHC), 13 with tox oplasmic chorioretinitis, 11 with herpetic uveitis and 11 with senile cataract (taken as controls) were analyzed by ELISA for IgG and IgG su bclasses. Three quotients (r1, IgG/albumin in serum; r2, IgG/albumin i n AH; and R, r2/r1) were calculated in order to estimate the local syn thesis (LS) of IgG and each IgG subclass. In AH of patients with herpe tic uveitis, a concomitant and significant increase of all IgG subclas ses as well as albumin (with no significant increase of r2 or R) was o bserved. This finding was interpreted as an indirect consequence of ma jor damage to the blood-aqueous barrier. In patients with FHC, a signi ficant increase of r2 and R involving only the IgG1 subclass was obser ved, indicating the existence of LS of IgG1 in the majority of these p atients. In the AH of patients with toxoplasmic chorioretinitis, no si gnificant modification of IgG subclass or albumin concentrations was o bserved when compared to controls. In conclusion, it would seem intere sting to consider measurement of IgG and IgG subclasses and calculatio n of the coefficients r1, r2 and R for a better evaluation of the loca l immunological processes observed in different types of uveitis.