Basic immunology

British Journal of Ophthalmology, 2000

Investigative Ophthalmology Visual Science, 1975

Primary immunogenic uveitis was induced in the rabbit eye with a single injection of antigen into the vitreous, and secondary booster uveitis responses were induced two months later by intravenous administration of the same antigen. The distribution of immunoglobulin classes and the specificity of the antibodies produced were assessed early and late in the primary response and early and late in the secondary response, and were compared with the analogous responses in the spleen and regional lymph nodes. At each of these stages of intraocular antibody response, IgG formation was higher and IgM formation lower than that seen in organized lymphoid tissues, while the proportion of IgA-forming cells was similar to the low levels usually found in the spleen. A significant proportion of IgA-forming cells was found in the perilimbal conjunctiva, and even greater levels in the lacrimal glands. At each stage of the response, the proportion of immxinoglobulin-forming cells making antibody specific for the inciting ovalbumin antigen was surprisingly low, reaching only seven per cent during the late primary reaction and 18 per cent during the late secondary reaction.

Progress in Retinal and Eye Research, 2003

This review focuses on several aspects of humoral immunologic defence of the ocular surface and intraocular compartment. Secretory IgA (sIgA) is a major component of lacrimal fluid and contributes to the first line of defence against infection of the ocular surface. Recent findings show that part of the lacrimal gland (LG) IgA repertoire consists of so-called natural IgA antibodies. How B cells responsible for these natural IgA antibodies are distributed to effector mucosal sites like the LG is not known. Extensive data are now available on the regionalization of mucosal IgA responses in murine gut, involving peritoneal B cells, the prototypic natural antibody producing cells. By comparing elaborate experiments done in mice with the much less extensive data on the LG, it becomes clear that this gland is a unique, but poorly investigated effector organ of the mucosal immune system. In addition to the humoral immune response at the surface of the eye, the production of antibodies within the ocular compartment also has several fascinating features. The detection of pathogen-specific antibodies in intraocular fluid (IOF) of uveitis patients is accepted as a diagnostic tool, but the specificity of these intraocular antibodies was not investigated in much detail. Recent data however, demonstrate that even antibodies recognizing the same antigen in both serum and IOF still differ in the epitopes they recognize. This reveals that the intraocular compartment largely determines its own antibody profile in the defence against intra-ocular pathogens. Several models as to how an exclusive intra-ocular B cell repertoire may be generated are presented.

Documenta Ophthalmologica, 1986

Inflammatory processes can involve any tissue in the eye. Despite advances in therapy, the sequelae of inflammation continue to be a major cause of visual impairment. Knowledge of disease pathogenesis in clinical ocular inflammations remains imprecise, and defined models are crucial in developing this understanding and evolving rational approaches to treatment. This review analyzes the contributions that studies of the classical and Arthus ocular Arthus-type reactions have made as to how the eye functions as an immunological entity. The anticipated development of therapeutic agents that may modulate immune processes with remarkable specificity, gives a new impetus to such experimental studies.

The ocular surface is constantly exposed to a wide array of microorganisms. The ability of the outer ocular system to recognize pathogens as foreign and eliminate them is critical to retain corneal transparency, hence preservation of sight. Therefore, a combination of mechanical, anatomical, and immunological defense mechanisms has evolved to protect the outer eye. These host defense mechanisms are classified as either a native, nonspecific defense or a specifically acquired immunological defense requiring previous exposure to an antigen and the development of specific immunity. Sight-threatening immunopathology with autologous cell damage also can take place after these reactions. This article discusses the innate and acquired corneal elements of the immune defense at the ocular surface. The relative roles of the various factors contributing to prevention of eye infection remain to be fully defined.

Clinical Immunology and Immunopathology, 1985

Mucosal Immunology, 2005

This immunologic role is mediated primarily through secretory IgA (S-IgA) antibodies, which are known to inhibit viral adhesion and internalization; prevent bacterial attachment, colonization, and activity; interfere with parasitic infestation; and reduce antigen-related damage in mucosal sites (Underdown and Schiff, 1986; Mestecky and McGhee, 1987; Childers et al., 1989; Ogra et al., 1999).Thus, the ocular mucosal immune system appears to protect the eye against allergic, inflammatory, and infectious disease, thereby promoting conjunctival and corneal integrity and preserving visual acuity. This chapter reviews the immunologic architecture and regulation of the ocular mucosal immune system and explores the impact of ocular infection and autoimmune disease on this system's structure and function. For information on nonmucosal aspects of ocular immunity, such as anterior chamber-associated immune deviation and retinal immunology, the reader may refer to several excellent sources

Encyclopedia of the Eye, 2010

Eye, 1990

The immunohistopathological findings of enucleated eyes and immunological abnormalities in several clinical disorders which result in intraocular inftammation are presented. With current immunological techniques, it is possible to define the type and activation status of the cells infiltrating the tissues. In all eyes examined, the predominant cell type was of activated CD4+ T-cells suggesting that the mechanisms involved in the perpetuation of the inOammatory response are similar and it is the initiating events which are likely to determine the site of pathology. The effects of activated CD4+ T-cells and the lymphokines they secrete in the chronic inOamma tory process in the ocular tissues are discussed.

Delhi Journal of Ophthalmology, 2018

Hypersensitivity reactions are our own immune responses to various triggering factors. These immune responses result in different clinical presentations of various ocular diseases. Various cytokines, interleukins are responsible for a myriad of symptoms and thus our therapy should be targeted on specific immunological pathways. In this article we have summarized various ocular diseases with the causative immune pathways thus simplifying the underlying cause. This article will help in understanding why similar looking diseases may have requirement for different modalities of treatment or why similar medications may work in different ocular diseases.