Immunological responses in the eyelid and orbit

Ocular adnexal lymphoma: an updated review of pathogenesis, diagnosis, and treatment

Lymphoma is the most common primary tumor of the orbit, accounting for 55% of all orbital malignancies. When divided into histopathological subtypes, extranodal marginal zone lymphoma of mucosa-associated lymphoid tissue (MALT lymphoma) comprises the largest proportion. Clinical manifestations are unspecific, but in patients with slow-growing painless orbital mass, or red conjunctival lesion suggestive of ‘salmon patch’, ocular adnexa lymphoma (OAL) should be suspected. Although the pathogenetic mechanism of ocular adnexal MALT lymphoma (OAML) is not yet fully understood, the relationship between OAML and Chlamydia psittaci has been hypothesized recently, similar to that between gastric MALT lymphoma and Helicobacter pylori. This suggests a new treatment option for OAML; bacterial eradication therapy with systemic antibiotics. Several other treatment methods for OAML have been introduced, but no treatment guidelines have been established yet. In this article, we summarize the current knowledge on the clinical features, pathogenesis, diagnostic methods, therapeutic strategies, and prognosis of OAML.

Innate Immunity and Biological Therapies for the Treatment of Sjögren's Syndrome

Sjögren's syndrome (SS) is a systemic autoimmune disorder affecting approximately 3% of the population in the United States. This disease has a female predilection and affects exocrine glands, including lacrimal and salivary glands. Dry eyes and dry mouths are the most common symptoms due to the loss of salivary and lacrimal gland function. Symptoms become more severe in secondary SS, where SS is present along with other autoimmune diseases like systemic lupus erythematosus, systemic sclerosis, or rheumatoid arthritis. It is known that aberrant activation of immune cells plays an important role in disease progression, however, the mechanism for these pathological changes in the immune system remains largely unknown. This review highlights the role of different immune cells in disease development, therapeutic treatments, and future strategies that are available to target various immune cells to cure the disease.

Morphological characterization of canine retrobulbar lymphoma

This report characterized seven cases of canine retrobulbar lymphoma that have been diagnosed during 2008 to 2014 by immunophenotyping of CD3 and Pax5. Classification of lymphoma were performed according to the revised WHO guidelines. Four retrobulbar lymphomas were of T-cell origin, while the others were of B-cell. Out of 7 cases, four subtypes were diagnosed in this study; T-cell-rich large B-cell lymphoma (3/7), T-cell lymphoblastic lymphoma (2/7), peripheral T-cell lymphoma (1/7), and cutaneous nonepitheliotropic lymphoma (1/7). T-cell-rich large B-cell lymphoma was found to be the most frequent subtype found.

Increased generation of fibrocytes in thyroid-associated ophthalmopathy

CONTEXT

The pathogenic basis for Graves' disease (GD) continues to elude our understanding. Specifically why activating antibodies are generated against self-antigens remains uncertain as does the identity of the antigen(s) that provokes orbital involvement in GD, a process known as thyroid-associated ophthalmopathy (TAO).

OBJECTIVE

The aim of the study was to determine whether CD34(+) fibrocytes are generated more frequently in GD, whether they infiltrate orbital connective tissues in TAO, and whether they express the thyrotropin receptor (TSHR).

DESIGN/SETTING/PARTICIPANTS

Generation of fibrocytes from peripheral blood mononuclear cells was examined in samples from 70 patients with GD and 25 healthy control subjects. Fibrocytes were characterized by flow cytometry. Orbital tissues and fibroblast culture strains were examined for their presence.

MAIN OUTCOME MEASURES

The frequency of CD34(+) fibrocyte generation from peripheral blood cells, characterization of their phenotype, cytokine production, and their presence in affected orbital tissues were analyzed.

RESULTS

CD34(+)CXCR4(+)Col I(+) fibrocytes expressing IGF-I receptor are far more frequently generated from cultured peripheral blood mononuclear cells of donors with GD compared with healthy subjects. They express TSHR at high levels and TSH induces fibrocytes to produce IL-6 and TNF-alpha. Numerous CD34(+) fibrocytes were detected in orbital tissues in TAO but were absent in healthy orbits. Tissue-infiltrating fibrocytes express TSHR in situ and comprise a subpopulation of TAO-derived orbital fibroblasts.

CONCLUSIONS

Our findings suggest that fibrocytes may participate in the pathogenesis of TAO because they express relevant autoantigens such as IGF-I receptor and functional TSHR and differentially accumulate in orbital tissue in TAO.

Ophthalmic lymphoma: epidemiology and pathogenesis

With a lifetime risk of 1% and 700 new cases per year, Non-Hodgkin lymphoma (NHL) is the seventh most frequent type of cancer in Denmark. The incidence of NHL has increased considerably in Western countries over the last decades; consequently, NHL is an increasing clinical problem. Ophthalmic lymphoma, (lymphoma localized in the ocular region, i.e. eyelid, conjunctiva, lacrimal sac, lacrimal gland, orbit, or intraocularly) is relatively uncommon, accounting for 5%-10% of all extranodal lymphomas. It is, however, the most common orbital malignancy. The purpose of this thesis was to review specimens from all Danish patients with a diagnosis of ophthalmic lymphoma during the period 1980-2005, in order to determine the distribution of lymphoma subtypes, and the incidence- and time trends in incidence for ophthalmic lymphoma. Furthermore, an extended analysis of the most frequent subtype, extranodal marginal zone lymphoma (MALT lymphoma), was done to analyse clinical factors and cytogenetic changes with influence on prognosis. A total of 228 Danish patients with a biopsy-reviewed verified diagnosis of ocular adnexal-, orbital-, or intraocular lymphoma were identified. We found that more than 50% of orbital- and ocular adnexal lymphomas were of the MALT lymphoma subtype, whereas diffuse large B-cell lymphoma (DLBCL) predominated intraocularly (Sjo et al. 2008a). Furthermore, lymphoma arising in the lacrimal sac was surprisingly predominantly DLBCL (Sjo et al. 2006). Incidence rates were highly dependent on patient age. There was an increase in incidence rates for the whole population from 1980 to 2005, corresponding to an annual average increase of 3.4% (Sjo et al. 2008a). MALT lymphoma arising in the ocular region was found in 116 patients (Sjo et al. 2008b). One third of patients had a relapse or progression of disease after initial therapy and relapses were frequently found at extra-ocular sites. Overall survival, however, was not significantly poorer for patients with relapse. Furthermore, we found that the frequency of translocations involving the MALT1- and IGH-gene loci is low in ocular region MALT lymphoma (2 of 42, 5%), but may predict increased risk of relapse (Sjo et al. 2008b). In conclusion the incidence of ophthalmic lymphoma is increasing at a high rate in Denmark. Ophthalmic lymphoma consists primarily of MALT lymphoma. The molecular pathogenesis of MALT lymphoma arising in the ocular region rarely involves translocations in the MALT1- and IGH-gene loci.

Potential antigen-presenting cells in normal extraocular muscles demonstrated with double immunoenzyme staining

Antigen-presenting cells are of crucial importance for the initiation and regulation of regional immune responses. In a previous study, indirect morphological evidence that morphologically normal human orbital tissues contain HLA-DR-positive macrophages, which may represent antigen-presenting cells, has ben obtained. In the present study, these cells were characterized in detail using double immunoenzyme staining techniques with monoclonal antibodies directed against several well-characterized monocyte/macrophage markers and against HLA-DR gene products. The orbital muscular tissues appear to contain numerous HLA-DR, monocyte/macrophage marker double-stained cells, which are considered to be potential antigen-presenting cells. The cells are widely distributed in the connective tissue of all the orbital muscular tissues studied and consist of several subsets with different phenotypes. Furthermore, site-specific differences were shown between recti muscles and the levator/Müller's muscles with respect to the distribution of HLA-DR and one monocyte/macrophage marker (OKM5). Many of the orbital antigen-presenting cells appear to be of the dendritic type and are considered to be of major importance in regulating local orbital immunity.