Long-term antigen specific and non-specific T-cell lines and clones in uveitis

T-cell lines, initially expanded with either mitogens or the uveitogenic S-antigen obtained from the eyes of three uveitis patients, were maintained in vitro for 4-8 weeks. S-antigen specific T-cell clones were derived from the peripheral blood of a fourth patient. The surface marker characteristics clearly demonstrate these cells to be T-cells. Both OKT4+ and OKT8+ clones and cell lines were found using immunofluorescence microscopy, an ELISA technique, or the laser cytofluorograph, but some could be only definitely identified as T-cells with the antibody to the IL-2 receptor, and not the OKT series of monoclonal anti-sera. These studies underscore how dynamic the expression of T-cell membrane markers can be, and that commercially available monoclonal anti-sera to T-cell membrane markers may not identify all T-cells in long term culture. This is the first report of the isolation of an antigen specific T-cell clone relevant to the eye, and the technique described will allow clonal expansion of ocular cells in order to study their functional characteristics.

Retinal S antigen reactivity in patients with retinitis pigmentosa and Usher's syndrome

Cell-mediated immunity to retinal antigens as determined by in vitro assays has been detected in a variety of retinal degenerative and retinal destructive conditions. The authors studied the in vitro reactivity to the soluble retinal S antigen of peripheral blood mononuclear cells from patients with simplex and multiplex retinitis pigmentosa (RP) and Usher's syndrome along with normal controls. The cellular stimulation index (SI) was calculated by comparing 3H-thymidine incorporation in cells exposed to either purified S antigen, crude whole human retinal antigen, or human choroidal antigen with that in unstimulated control cultures. Eight of 15 patients with RP and 5 of 6 with Usher's had a SI greater than the tolerance limits of normal values. These results indicate that the immune system may be involved either primarily or secondarily in RP.

Involvement of the pineal gland in rats with experimental autoimmune uveitis

Pineal glands of rats with experimentally induced autoimmune uveitis (EAU) were studied histologically. Inflammatory changes, characterized by mononuclear infiltration, were found in the pineal glands of one-third of the Lewis rats that developed EAU by active immunization with S-antigen. No changes in the pineal gland were observed in AVN rats which are "low responders" for EAU and did not develop ocular disease. Frequency and severity of both pineal gland and ocular involvement clearly were elevated by intravenous injection of Bordetella pertussis along with the S-antigen immunization; all B. pertussis-treated rats of both Lewis and AVN strains developed pineal and ocular changes. Inflammatory changes of the pineal gland also were found in rats in which EAU was induced passively by transfer of lymphocytes from S-antigen-immunized donors. The frequency of involvement of the pineal gland was found to be lower than that of the retinas in rats where EAU was induced by active immunization or by adoptive transfer of lymphocytes.

Cyclosporin A therapy in the treatment of intraocular inflammatory disease resistant to systemic corticosteroids and cytotoxic agents

Sixteen patients (ten women and six men, ranging in age from 20 to 67 years) with active bilateral posterior uveitis of noninfectious origin were treated with cyclosporin A, a specific anti-T-cell medication. All had previously received systemic corticosteroids or cytotoxic agents or both and had responded poorly or had intolerable side effects. Fifteen of 16 patients had positive responses to oral cyclosporin A therapy (initially 10 mg/kg of body weight/day), measured by a decrease in inflammatory activity, with a concomitant improvement in visual acuity in most patients. Fluorescein angiographic findings varied considerably with some patients showing an improvement with continued cystoid macular edema. Renal toxicity occurred in five patients, but renal function reverted toward normal with a decrease in cyclosporin A dosage.

Multicentric Kaposi's sarcoma of the conjunctiva in a male homosexual with the acquired immunodeficiency syndrome

A 38-year-old male homosexual with the new Acquired Immunodeficiency Syndrome (AIDS) had biopsy proven Kaposi's sarcoma of the right palpebral conjunctiva, extraocular mucocutaneous areas, and lymph nodes. Histologically, the palpebral tumor was characterized by atypical spindle cell proliferation and multiple slit-like vessels. Staining for Factor VIII-related antigen was positive in the cytoplasm of some tumor cells. Electron microscopy disclosed Weibel-Palade bodies in cells lining scattered slit-like vascular channels. The palpebral tumor mass was relatively nonadherent to its surrounding tissues and thus its simple excision was noteworthy; despite the prominent vascularity of the tumor, minimal bleeding was associated with its surgical resection. Any patient with AIDS should have all mucosal surfaces routinely examined for the presence of Kaposi's sarcoma lesions.

Treatment of intraocular inflammatory disease with cyclosporin A

Eight patients with bilateral sight-threatening posterior uveitis of non-infectious aetiology that had not responded to corticosteroid or cytotoxic therapy were given cyclosporin A. Seven of the eight responded with improvement in visual acuity and disappearance of ocular inflammatory activity. The seven included two with Behçet's disease, who also had improvement in non-ocular symptoms. Peripheral blood lymphocytes from the seven cyclosporin A responsive patients, but not those from the non-responder, gave positive in-vitro blastogenic responses to the retinal S-antigen, a highly uveitogenic organ-specific material. In four patients OKT4/OKT8 ratios fell after the start of therapy, as the result of an increase in the OKT8 fraction. In the other four patients the fall was preceded by an increase in the OKT4/OKT8 ratio. Cyclosporin A did not influence natural killer cell activity. Side-effects ascribed to cyclosporin A were tolerated or disappeared with continued therapy, sometimes at a lower dosage. No neoplasms were observed. Cyclosporin A seems to be effective treatment for selected patients with severe bilateral uveitis of non-infectious aetiology.

T lymphocyte subsets in uveitis

We evaluated the peripheral T-cell subsets in 32 adult patients with intraocular inflammatory disease and 12 age-matched normal controls by means of the OKT series of monoclonal antibodies in conjunction with the laser cytofluorograph, which quantitatively determines the fluorescence intensity of lymphocytes. We found no statistically significant difference in the ratio of OKT 4-positive (inducer) cells to OKT8-positive (suppressor) cells. However, this ratio was significantly decreased in patients with active posterior uveitis compared with controls (P less than .05). The number of OKT8-positive T lymphocytes in this group was significantly increased (P less than .01), causing a decrease in the OKT4-OKT8 ratio. In patients with positive in vitro cell-mediated responses to the retinal S-antigen, a statistically significant (P less than .05) decrease was found as well only in the patients with active disease.

Cyclosporin A: alterations of the cellular immune response in S-antigen-induced experimental autoimmune uveitis

We have previously shown that Cyclosporin A (CsA) is effective in preventing S-antigen (S-Ag)-induced experimental autoimmune uveitis (EAU). Lewis rats, which readily develop EAU, were studied for the alterations in cell-mediated immune functions associated with CsA therapy. Lymph nodes draining the site of S-Ag immunization were significantly smaller in the CsA-treated animals when compared to the nonprotected group (p less than 0.01), and also showed profound histologic alterations when compared to controls. In vitro responses of lymphocytes from lymph node and peripheral blood were greatly diminished in the CsA-treated animals. Sera from rats treated with CsA also were capable of inhibiting in vitro proliferative responses. These findings demonstrate that CsA-treated Lewis rats have alterations in several cell-mediated immune functions, thereby not permitting full development of the immune events that ultimately lead to uveitis.

Birdshot retinochoroidopathy associated with HLA-A29 antigen and immune responsiveness to retinal S-antigen

Antigen HLA-A29 was present in 16 of 20 patients (80%) with birdshot retinochoroidopathy, but only in 31 of 418 controls (7.4%) (P less than .0001). The relative risk for this disease in persons possessing HLA-A29 antigen was 49.9, one of the highest reported. Of the 20 patients, 13 were also tested for evidence of an in vitro mitotic immune response to purified retinal S-antigen. Of these, 12 (92.3%) responded to the purified preparation, whereas one responded only to a crude retinal homogenate. The histopathologic and clinical findings in an eye from one of the responders to the S-antigen were similar to those in the disease induced in monkeys with the S-antigen. Our findings suggested that birdshot retinochoroidopathy has a genetic predisposition and that retinal autoimmunity, resulting from the S-antigen or other retinal antigens, plays a role in the manifestation of this disease.

Modulation of experimental autoimmune uveitis with cyclosporin A

Cyclosporin A has been shown to be an effective inhibitor of T cell-mediated diseases. We show here that cyclosporin A was capable of totally preventing the clinical appearance of experimental autoimmune uveitis in Lewis rats, even when administered on an every-other-day schedule (10 mg/kg) or when begun seven days after immunization (40 mg/kg). At lower doses of the drug, a modulation of the disease was seen with evidence of a more chronic, granulomatous process. A long-lasting unresponsive state to the immunizing antigen was not uniformly induced with cyclosporin A if therapy was begun seven days after S antigen immunization. Because of cyclosporin A's effective control of this experimental model that is induced by an antigen to which certain patients with uveitis demonstrate cell-mediated immune responses, cyclosporin A may be an effective mode of therapy for T cell-mediated intraocular inflammatory disease.

Experimental autoimmune uveitis in the athymic nude rat

A single injection of the retinal soluble antigen (S-Ag, 30 micrograms) to the Lewis or the heterozygous (rnu/+) rats induces a severe bilateral uveitis, characterized initially by infiltration of the retina with inflammatory cells. The athymic nude rat (homozygous rnu/rnu), which lacks the thymus gland and T cell-mediated functions, does not develop ocular inflammatory disease, clinically of histologically, after repeated challenges with S-Ag. Circulating anti-S-Ag antibodies were found in S-Ag-immunized Lewis rats and in the heterozygous, but not the athymic nude rats. Good proliferative responses to concanavalin A, S-Ag and purified protein derivitive of tuberculin (PPD) were found in lymphocyte cultures prepared from the draining lymph nodes of immunized heterozygous rats, but not when lymphocytes from the athymic nude rats were used. Uveitis could be induced in the athymic nude rat when lymphocytes from S-Ag-immunized heterozygous rats were transferred to them. By stimulating the donor lymphocytes in vitro with S-Ag before transfer, the number of recipients that developed uveitis was increased. On the other hand, it was impossible to transfer disease with hyperimmune serum alone. The possible role of T lymphocytes in the induction of experimental autoimmune uveitis with S-Ag is discussed.

Resemblance between rhodopsin kinase and S-antigen induced uveitis

The retinal S-antigen (S-Ag) has been shown to induce uveitis effectively in subhuman primates, and lymphocytes from patients with certain uveitic conditions show cell-mediated responses to this antigen. Rhodopsin kinase (RK), an enzyme probably unique to the mammalian eye, is reported here to resemble the retinal S-Ag in its capacity to induce uveitis in experimental animals. A histological comparison of rat eyes taken 2 and 3 weeks after immunisation with either RK or S-Ag reveals essentially identical pathological alterations. Ocular inflammation is seen in both the anterior and posterior portion of the globe. Areas of focal degeneration of the photo-receptor layer, from which both the S-Ag and RK are extracted, could be seen in both RK and S-Ag immunised animals. Cells from draining lymph nodes of both groups responded by increased thymidine incorporation when cultured in the presence of either RK or S-Ag. In addition antibodies directed against the S-Ag were detected in both groups. These findings, in addition to the biochemical similarities of these preparations, reported elsewhere, would strongly suggest that RK and S-Ag are one and the same. The identification of potentially uveitogenic ocular antigens could help to reclassify uveitic entities that at present have clinically similar courses.

S-antigen uveitis in primates. A new model for human disease

Uveitis was induced rhesus monkeys immunized with purified retinal S-antigen. Focal retinal and subretinal infiltration, in addition to periphlebitic changes, were observed histologically. Immunized monkeys had similar cell-mediated in vitro immune responses to the S-antigen as do humans with posterior uveitis. Circulating immune complexes at the time of disease could not be detected. This primate model supports the notion that the S-antigen may play a role in human uveitis.

Iridocyclitis in black Americans: association with HLA B8 suggests an autoimmune aetiology

Histocompatibility (HLA) testing was performed on a total of 171 black Americans, 129 controls, and 42 patients with iridocyclitis. None of the patients had a history of rheumatological disease. The phenotype frequency of HLA B8 was greatly increased among patients than the control group (exact p = 0.0010). Most striking was the almost identical phenotypic frequency of B27 found in patients and in the control group (exact p = 0.07087). No HLA DR antigen in the patient group was found to be significantly raised when compared with controls. The HLA B8 associated diseases was seen more in females, was bilateral and nongranulomatous, had no systemic disease associated with it, and left patients with visual handicap. The HLA B8 antigen has been associated with various entities of presumed autoimmune origin, and these data suggest that iridocyclitis, at least in blacks, may be of similar aetiology.

Cyclosporin a. Inhibition of experimental autoimmune uveitis in Lewis rats

Cyclosporin A (CS-A), a selective inhibitor of T lymphocytes, is reported here to prevent S antigen (S-Ag) induced uveitis in Lewis rats. The S-Ag, found in all mammalian retinas, is uveitogenic under experimental conditions and patients with certain uveitic entities demonstrate cell mediated responses to this antigen. Daily treatment with CS-A (10 mg/kg) begun on the same day as S-Ag immunization totally inhibited the development of the uveitis in this experimental autoimmune model. Moreover a greater CS-A dose (40 mg/kg) efficiently prevented the disease process when therapy was started 7 d after S-Ag immunization. Anti-S-Ag antibody titers were observed to be similar in rats either protected or not protected with CS-A. Our data support strongly the need for T cell participation in this disease model. Since ocular inflammatory disease is an important cause of visual impairment, the data further suggest that CS-A may be useful in the treatment of patients with intractable uveitis.

Altered suppressor-cell activities in uveitis

Suppressor-cell function was evaluated by two in-vitro assay systems in forty patients with intraocular inflammatory disease (uveitis) and in sixteen healthy age-matched controls. A concanavalin-A (Con A)-induced suppressor-cell assay showed that patients with posterior uveitic conditions had greater suppressor activity than did the anterior uveitic group or the control group (p < 0.005); but an assay for non-induced suppressor-cell activity showed that the posterior uveitic group had less suppressor activity (p < 0.001). These findings suggest (a) that at least two cell types may be involved in immunoregulation, and (b) that not all diseases of presumed autoimmune origin are the result of reduced suppressor activity, which has been shown in some "autoimmune" conditions.

Optic neuritis and chronic relapsing experimental allergic encephalomyelitis: relationship to clinical course and comparison with multiple sclerosis

Optic nerve tissue from strain 13 guinea pigs sensitized for chronic (relapsing) experimental allergic encephalomyelitis has been examined up to 3 years postinoculation. The changes were compared with the clinical history in each case, with lesions occurring elsewhere in the central nervous system and with optic nerve tissue from a single case of chronic multiple sclerosis. In chronic experimental allergic encephalomyelitis was found that optic neuritis was a consistent finding. Active lesions in the optic nerve were a feature of animals sampled up to 4 months postinoculation. Unlike lesions in the spinal cord, changes occurring in long term animals did not parallel clinical signs. The absence of active lesions in long term animals was apparently not due to a resistance to recurrent disease on the part of the tissue since a second challenge with central nervour system tissue was capable of producing active inflammation in the optic nerve. It appears, therefore, that in its unmanipulated state, chronic experimental allergic encephalomyelitis is more a disease of the spinal cord. Optic nerve changes in the case of multiple sclerosis did not compare well with the guinea pit lesions--discrepancies which we speculate as being related to differences in anatomy, age, species, and longevity of the disease process (among others), rather than a difference in pathogenesis.

Cellular immune responsiveness of uveitis patients to retinal S-antigen

S-antigen, an organ-specific substance isolated from the retinal photoreceptor region, was shown to be a potent agent for the induction of experimental autoimmune uveitis. S-antigen and other ocular antigens were tested for their ability to induce blast transformation of lymphocytes from patients with a variety of ocular inflammatory diseases. Lymphocytes from 22% of patients tested manifested a positive memory response to the S-antigen prepared from bovine eyes. Responses to human S-antigen paralleled those found with the bovine. All of those with a positive response had active or inactive retinal lesions. Some posterior uveitis patients responded to crude retinal extracts but not to S-antigen, indicating the possible role of other retinal antigens still to be purified. Control subjects did not manifest a positive immune response to the S-antigen, nor did patients with anterior uveitis. Possibly, these responses play some role in the pathogenesis of the disease.