Radioimmunoassay for toxoplasmosis

Antibody patterns in the serological diagnosis of acute lymphadenopathic toxoplasmosis

Sera from six patients at various stages of acute lymphadenopathic toxoplasmosis were tested using nine different types of test currently available for the serological diagnosis of the disease. A diagnosis was made on positive serology in three of the patients. The antibody patterns of two of these patients were studied over a period of six months and the third was studied over two months. A diagnosis was made on lymph node morphology in the other three cases. Two serum samples were tested from each of these patients. The results obtained suggest that a rationalisation of the types of test used should be encouraged and that an enzyme-linked immunosorbent assay (ELISA) for parasite-specific IgG and an antibody class capture ELISA for parasite-specific IgM are sufficient to confirm the diagnosis of acute lymphadenopathic toxoplasmosis.

The antigenic structure of Toxoplasma gondii: a review

Even though T. gondii is ubiquitous in the animal kingdom, definitive information on its antigenic structure has only become available over the last few years, largely as a result of recent advances in immunology and biochemistry. New knowledge in this area will enable the immune response to the parasite to be studied in greater detail and may lead to the development of newer, more meaningful diagnostic tests for toxoplasmosis, and possibly a vaccine against it. This paper reviews knowledge on the antigenic structure of this extremely widespread and important protozoan parasite.

Simultaneous radioimmunoassay for specific antibodies to members of the human herpesvirus group

A method of described for the simultaneous radioimmunoassay (RIA) for antibody to members of the human herpesvirus group. The RIA is compared with some of the conventional serologic techniques used to quantitate antibody to these viruses (Epstein-Barr virus, cytomegalovirus, herpesvirus type 1 and varicella-zoster virus). Color-coded beads, each coated with the antigens of a different herpesvirus, were similtaneously placed in a well which contained a human serum to be assayed for antibody to each of these 4 viruses. The results of this test were compared with the results obtained when the serum was assayed for antibody to the 4 viruses in 4 separate tests. We conclude that the antigen-antibody reactions do not significantly interfere with each other when a serum is assayed for antibody to the 4 viruses simultaneously. A comparison of the RIA with conventional serologic techniques shows excellent correlation in the antibody titers obtained. Features of the solid-phase RIA allow significant savings of time, reagents and space, and thus make it feasible for the small laboratory to screen large numbers of sera for antibody to a variety of antigens.