Clinics in Immunology and Allergy最新文献

Abnormalities of genetic expression associated with malignant transformation cause a number of phenotypic changes including the production of substances by cancer cells which differ quantitatively or qualitatively from the products of normal cells. These ‘cancer markers’ or tumour associated antigens may be used as objective parameters in screening, diagnosis, staging, histopathological evaluation and monitoring treatment of non-lymphoid neoplasia. Specific and sensitive tests for alphafetoprotein, carcinoembryonic antigen, human chorionic gonadotropin and a number of other cancer markers have been developed. Established tests rely upon polyclonal heterologous antisera in radioimmunoassay or enzyme-linked immunoassay. Theoretical advantages of monoclonal antibodies in this setting have yet to be realized. Monoclonal antibodies do however show practical advantages over extensively absorbed polyclonal antisera in the histopathological evaluation of solid tumours and further progress with these reagents is expected. Studies of host-tumour immunological interactions suggest that future routine investigations of non-lymphoid neoplasia may include assessments of autochthonous reactivity.

CIC occur in numerous disorders. A review is given of the currently most widely used and best standardized immune complex assays and their clinical applications. Special emphasis is given to these disorders in which the results of IC assays have been shown to be of clinical importance to establish a diagnosis or prognosis or to monitor disease activity and treatment efficacy. The use of IC assays for this purpose is justified in only a relatively small number of disorders.

Man’s respiratory tract is a major and intimate interface with his environment. Any deficiency in its defences will be quickly capitalized upon by microorganisms, and any generalized host defence defect will therefore often have its major manifestation or presentation as respiratory symptoms.

A high index of suspicion of a deficiency in respiratory defences must therefore be exercised when considering severe or frequent upper and/or lower respiratory tract infections.

The clinical and laboratory investigations of a suspected deficiency should proceed from the simple clinic screening to more complex tests, a few requiring admission to hospital. Non-immunological deficiencies should be considered as well as immunity deficiencies because a considerable part of the lung’s defences are non-specific. Logical investigation will lead to accurate diagnosis and logical treatment.

A final decision should always be made as to whether any defect demonstrated is truly primary or merely secondary to underlying disease.

The service offered by clinical immunology laboratories should include not only the monitoring of complement activation but also the detection of complement deficiency syndromes. The total haemolytic complement assay, the alternative pathway haemolytic assay and the C3–C9 assay are simple to perform and their results locate the missing component to the classical pathway, the alternative pathways or the terminal sequences. Identification of the missing component requires the use of functional and immunochemical assays of individual components. These permit the discrimination between absence of a component, or the presence of a functionally inactive variant.

The clinical value of qualitative and quantitative laboratory investigations of immunoglobulins is now well recognized. The essential measurement of the major immunoglobulins (IgG, IgA and IgM) in the diagnosis and monitoring of both primary and secondary antibody deficiency diseases is well established and in addition many diseases are associated with a characteristic pattern of immunoglobulin increases. The quantitation of both total and specific IgE also has an important role in the investigation of atopic disease.

Electrophoresis of serum and urine is essential in the diagnosis of paraproteinaemia and quantitation of immunoglobulins and paraprotein is helpful in assessing the significance of paraproteinaemia both at diagnosis and in follow-up studies.

The quantitative estimation of IgG, to determine intrathecal synthesis, and the presence of oligoclonal bands in the cerebrospinal fluid constitute important aids in the diagnosis of demyelinating diseases such as multiple sclerosis.