Evaluation of eosinophilic inflammation in a novel murine atopic keratoconjunctivitis model induced by crude Dermatophagoides farinae antigen

BACKGROUND

The purpose of this study is to conduct a histopathological research of the conjunctival findings and eosinophilic inflammation of novel atopic keratoconjunctivitis in a NC/Nga mouse model using crude Dermatophagoides farina.

METHODS

NC/Nga mice were sensitized by repeated topical applications of an ointment containing Dermatophagoides farinae body (Dfb). They were then divided into 4 groups depending on the following topical ophthalmic treatment: DFb group undergoing topical ophthalmic ointment containing Dfb; DFco group undergoing topical instillation of allergen extracts of Dermatophagoides farinae; Ba group undergoing topical ointment with substrate alone and NT group without after-topical ophthalmic treatment. At 24 hours after the last ophthalmic treatment, histopathological examination was performed. The density of the subepithelial infiltration of the eosinophils was determined. Serum total IgE and house-dust-mite (HDM)-specific IgE antibody concentrations were determined by enzyme-linked immunosorbent assay (ELISA).

RESULTS

In the DFb group, the conjunctiva showed similar findings to those of atopic keratoconjunctivitis, i.e. intraepithelial pseudotubular formation, Torus-form infiltration due to massive lymphocytes in the palpebral conjunctiva and gelatinous hyperplasia in the limbus with subepithelial granuloma composed of lymphocytes and eosinophils. Subepithelial infiltration of eosinophil density in the DFb group [878.4 ± 399.7cells/mm2 (mean ± SD)] was significantly higher than in the other 2 groups (DFco 85.6 ± 40.1 Ba 49.2 ± 32.3) (P < 0.001). Total serum IgE concentration and HDM-specific serum IgE antibody concentration in the DFb group and the DFco group were significantly higher compared with those in the NT group.

CONCLUSIONS

Topical application of an ointment containing DFb to both the skin and eyes of NC/Nga mice can induce an atopic keratoconjunctivitis (AKC) model in these mice.

Efficacy of 1.25% and 1% topical cyclosporine in the treatment of severe vernal keratoconjunctivitis in childhood

Cyclosporine eyedrops 2% have been used for treatment of corticosteroid-resistant vernal keratoconjunctivitis (VKC) cases. The purpose of our study was to verify the efficacy of 1.25% vs. 1% topical cyclosporine in improving severe form of VKC in childhood. Twenty children with severe VKC, were enrolled in a double-blind, placebo-controlled study and received cyclosporine 1.25% in one eye for 2 wk. Then an open trial was conducted during the next 3 months and 2 wk. Thirty-two more patients were recruited the next year into a new open trial and they received cyclosporine 1% for 4 months. Ocular subjective symptoms and objective signs were scored in all children at entry, 2 wk and 4 months. Skin prick tests and conjunctival scraping tests were also performed; serum immunological and biochemical markers were assessed. The mean score values for severity of subjective symptoms and objective signs were significantly decreased after 2 wk, and 4 months, compared with those at entry (p < 0.001), in both groups of children who received cyclosporine eyedrops 1.25% and 1%, respectively. Serum markers did not differ from the beginning to the end of treatment. Conjunctival eosinophils and cyclosporine serum levels were not detectable at the end of therapy, nor were endothelial corneal cells damaged. Our findings suggest that 1% cyclosporine concentration might be the minimal effective treatment regimen to control symptoms and local inflammation in severe forms of VKC.

Tear and serum soluble leukocyte activation markers in conjunctival allergic diseases

PURPOSE

To measure markers of leukocyte activation in patients with an exclusively ocular inflammatory or bacterial disease.

METHODS

Neutrophil myeloperoxidase, eosinophil cationic protein, eosinophil neurotoxin, and soluble interleukin-2 receptor were measured in serum and tears of 17 patients with allergic vernal keratoconjunctivitis, seven with atopic keratoconjunctivitis, 11 with seasonal allergic conjunctivitis, seven with giant papillary conjunctivitis, 13 with rosacea blepharokeratoconjunctivitis, seven with bacterial conjunctivitis, and 13 normal subjects as controls.

RESULTS

In serum of patients with vernal and atopic keratoconjunctivitis, levels of eosinophil cationic protein, eosinophil neurotoxin, and interleukin-2 receptor were significantly increased compared with control subjects but were not correlated with the severity of ocular symptoms. In tears of patients with vernal and atopic keratoconjunctivitis and seasonal allergic conjunctivitis, as well as in the nonallergic diseases, rosacea blepharokeratoconjunctivitis and bacterial conjunctivitis, levels of eosinophil cationic protein, neurotoxin, and interleukin-2 receptor were significantly increased compared with control subjects. The highest values of these markers were found in vernal keratoconjunctivitis samples. Neutrophil myeloperoxidase was significantly increased in vernal and atopic keratoconjunctivitis, rosacea blepharokeratoconjunctivitis, and bacterial conjunctivitis. In vernal keratoconjunctivitis, tear markers were correlated to the clinical score of the disease, but not with cytology.

CONCLUSIONS

Tear histamine was measured in 10 allergic patients after allergen challenge. Although none of the above markers can be considered specific to a single disease, their measurement may still be useful for the quantification of local cell activation in ocular inflammatory diseases.

Lacrimal occlusion therapy for the treatment of superior limbic keratoconjunctivitis

Superior limbic keratoconjunctivitis (SLK) is a chronic and recalcitrant disease of the superior bulbar and tarsal conjunctiva, as well as the superior limbic aspect of the cornea. Both the etiology and the pathogenesis of this condition are poorly understood. Many treatment options have been advocated in the management of SLK, including: topical antibiotics, topical anti-inflammatory agents, topical vitamin A solutions, chemical cautery, thermal cautery, and surgical resection. Most recently, studies have suggested that lacrimal occlusion therapy may be beneficial in the treatment of SLK. A case is presented in which this method of treatment was used, with excellent results. The implications of this report suggest that the use of lacrimal occlusion in the management of SLK may be a viable treatment option before considering more radical and invasive therapy. In addition, this case helps to illustrate the significant link between SLK and thyroid disease.

The eosinophil and the eye

Personal studies in allergic eye diseases reviewed in this paper indicate that: 1. An increased number and an abnormal distribution of eosinophils is present in conjunctival biopsies of patients with vernal keratoconjunctivitis (VKC). 2. Eosinophil and eosinophil products, such as ECP, are also increased in tears of VKC patients and, in hay fever conjunctivitis, accumulate during the late-phase of allergic reaction following specific allergen challenge. 3. Circulating eosinophils of VKC patients show a typical activation phenotypic profile which is associated with increased serum level of eosinophil cationic protein and eosinophil-derived neurotoxin/protein X. A clinical study of the modulatory effect of cetirizine on the early and late phase of the allergic reaction as well as on the eosinophil activation and tissue recruitment following conjunctival allergen challenge is reported as an example of the need to evaluate eosinophil functions when investigating anti-allergic drugs. Drugs modulating various aspects of eosinophil function could play a primary role in the treatment of allergic eye disease.

Serum beta-2-microglobulin in Sjögren's syndrome

The serum concentration of beta-2-microglobulin was determined with a radioimmunoassay in 52 patients with keratoconjunctivitis sicca, 29 of whom had Sjögren's syndrone. Eleven (38%) of the patients with Sjögren's syndrome had high serum values. These cases had a higher mean age and a higher frequency of the complete triad of Sjögren's and of antinuclear antibodies than had the lower value cases. The sicca components per se did not seem to influence the serum concentration of beta-2-microglobulin. Most of the few complications occurred in patients with high values.

Bovine infectious keratoconjunctivitis: serological aspects of Moraxella bovis infection

A modification of a gel diffusion precipitin test (GDPT) was used to detect antibodies for Moraxella bovis (M. bovis) in the sera of cattle affected with bovine infectious keratoconjunctivitis (BIK). The test was also used for the detection of sequential antibody development in cattle vaccinated with cultures of M. bovis. Also, strains of M. bovis isolated from cattle herds affected with BIK were characterized serologically as a part of an identification scheme using the test.A comparison of the antigenic properties of various strains of M. bovis and M. bovis-like organisms was conducted using the test. The results indicated that there might be antigenic relationships between M. bovisand M. bovis-like organisms such as Moraxella liquefaciens, Moraxella nonliquefaciens, an unidentified hemolytic diplococcus, Mima polymorpha, Mima polymorpha var. oxidans and Herellea vaginicolaThe authors suggest that the GDPT can be used for serological studies of BIK, and the identification and antigenic analysis of M. bovis. They indicate, however, that a more definitive study is needed to evaluate the reliability of the test for quantitative work.