Immunoglobulins in aqueous humour and iris from patients with endogenous uveitis and patients with cataract.

Abstract

The scarcity of aqucous humour and uveal tissues from living patients has hampered studies on the immunological aspects of human eye diseases. There are many autopsy studies investigating the niature and amount of proteins in human aqueous, but it is known that the composition of aqueous humour changes very rapidly after death so that the validity of the results of these autopsy studies on the composition of aqueous humour is in doubt (Hemmingsen and Other, I967; Dieckhues, I967; Allansmith, Whitney, McClellan, and Newman, I973). Application of radial immunodiffusion (Mlancini, Carbonara, and Heremans, I965) has enabled us to estimate quantitatively IgG, IgMl, and IgA in the aqueous humour obtained before surgery from patients suffering from: (i) Active chronic endogenous uveitis, (ii) Narrow-angle glaucoma with no active inflammation, (iii) Senile cataracts.Small pieces of iris were also available from these patients for immunohistochemical study. Material and methodsSamples of aqueous humour collected just before surgery, taking care not to contaminate the aqueous with blood, were centrifuged in small glass test-tubes (6 mm. diameter with conical bottom) at i,ooo G. max. for I o min. to get rid of cells and tissue debris (if any). The clear supernatant was subjected to radial immunodiffusion in plates (Hyland Laboratories, California). Using a numbei of reference standards supplied by the Hyland Laboratories and the World Health Organization (W.H.O. Standard 67 87), the lowest protein concentrations which could be reliably measured by this method were: IgG, 5 mg./I00 ml.; 1gM, 4 mg. I00 ml.; IgA, 4 mg./ I00 ml.To assess the reproducibility of this method of immunoglobulin determination, ten repeated measurements of each of the three immunoglobulin classes were performed on a diluted pooled specimen of normal human serum. The coefficient of variation (standard deviations/mean concentration x ioo) of the IgG, IgM, and IgA determinations respectively were ±6, ±4, and ±7 pel cciet. Whenever the volume of aqueous humour was insufficient, the aqueous was subjected to immunoelectrophoresis against an antibody to whole human serum for qualitative detection of immunoglobulin fractions.Freshly excised pieces of iris (about 2 CU. mm.) were snapfiozen in a slurry of liquid nitrogen and isopentane (-i6oC.) and stored at 70°C. Air-dried unfixed 2 to 3 L cryostat sections of iris as well as parallel sections fixed in 5 per cent. glacial acetic acid in ethanol at -20°C. for I5 min.(Hijmans, Schuit, and Klein, I969) were washed three times in phosphate buffered saline (PBS,

Newer Immunological Studies of the Aqueous Humor in Uveitis

“…This elevation of C3 was found to show some parallelism with the intraocular increase of IgA. In uveitis, albumin and IgG levels are definitely elevated, as Ghose et al [1973] have already shown. Their study however does not relate these protein levels to the degree of flare and cells.…”

Intracameral Muramyl Dipeptide-Induced Paracellular Permeability Associated with Decreased Glutamate Transporter and g -Glutamyltranspeptidase Activities

“…Note that the appearance of IgG in the AH at 45 min post injection [ Fig. 1(C)] coincided with the paracellular permeability increase and is characteristic of uveitis (Ghose et al, 1973). Thus, we have elicited an uveitis-like condition in which the characteristic feature develops within a 15 min window (30-45 min) providing a unique opportunity for viewing underlying cellular mechanism.…”

“…Further, IgG (58 kD Fc fragment) was not detected in the control AH [ Fig. 1(C)] but was detected in the AH collected at 45 and 60 min post MDP injection, which is characteristic of eyes with uveitis (Ghose et al, 1973).…”

Immunological Features of Hla‐b27 Anterior Uveitis

“…18 Immune complexes have been extensivel) investigated in the sera and aqueous humor in AU,IX and although the results of the presenl study failed to reveal increased levels of immunt complexes, we have previously reported, using a more extensive battery of immune-compler assays, that such complexes are increased in tho HLA-B27-negative subgroup.8 Despite the lack of direct histological evidence for immune. complex deposition in man there is strong circumstantial and experimental evidence'' that such complexes may play a pathogenic role in certain patients with this disease.…”