Immunohistological demonstration of serum proteins and structural and viral antigens in paraffin sections of nervous tissues.

A brief outline is given of applications of immunohistological techniques to the study of normal and diseased nervous tissue. Protease treatment of paraffin sections usually enhances sensitivity and reliability both of IF and PAP techniques. Sensitivity of immunohistological examination of paraffin sections is comparable to that of virus detection by normal virological techniques in animal rabies and slightly superior to EM search for virions in SSPE and PML. Immunostaining for MBP appears to be the most sensitive method for myelin, especially for demonstration of very thin myelin sheaths, which are important in studies of myelogenesis and cortical myeloarchitecture. Prolonged fixation in formalin clearly diminishes or abolishes immunoreactivity. Compacted myelin stains less well for MBP than preparative myelin artefacts and the surface of myelinated fibers. GFAP production is enhanced when glioma cells invade surrounding mesenchymal structures. The chance finding of GFAP-like immunoreactivity in a cancer metastasis casts doubt on the astroglial specificity of GFAP.