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Neurocysticercosis (NCC), an infection of the brain by Taenia solium (Ts) cysts, is the most common cause of adult-onset epilepsy in developing countries. Serological testing consists primarily of varying methods to detect antibodies in body fluids and more recently antigen (Ag) detection assays to identify individuals or animals with viable parasites. Antigen assays currently in use employ monoclonal antibodies (mAbs) raised against T. saginata, which have known cross reactivity to animal cestodes but are highly specific in human samples. We produced, characterized and tested 21 mAbs raised against T. solium whole cyst antigens, vesicular fluid or excretory secretory products. Reactivity of the TsmAbs against specific cyst structures was determined using immunofluorescence and immunohistochemistry on histological sections of Ts muscle cysts. Four TsmAbs reacted to vesicular space alone, 9 to the neck and cyst wall, one to the neck and vesicular space and 7 to the neck, cyst wall and vesicular space. An in-house ELISA assay to detect circulating Ts antigen, using the TsmAbs as capture antibodies and a rabbit polyclonal anti-Ts whole cyst antibody as a detector antibody demonstrated that eight of the 21 TsmAbs detected antigens in known NCC-positive human sera and three of these also in urine samples. Reactivity was expressed as normalized ratios of optical densities (OD positive control/OD negative control). Three TsmAbs had ratios >10 and five between 2 and 10. The TsmAbs have potential utility for the diagnosis and post-treatment monitoring of patients with viable NCC infections.

Female Blackface lambs expected to exhibit genetic variability for resistance to gastrointestinal nematodes, were either exposed to continuous experimental infections of Teladorsagia circumcincta or were sham-dosed to monitor phenotypic responses to infection. As a measure of parasitism and host response, worm-eggs in faeces (faecal egg count, FEC) were counted over a 3-month period and worm burdens were ascertained at post-mortem. The host response to the infection was also measured by differential counts of white blood cells, anti-T. circumcincta IgA antibody levels and body weight. Results suggest that nematode abundance (mean number of parasites per host) and prevalence (proportion of infected animals) were maximal shortly after the beginning of infection (21 days p.i.) when virtually all the infected animals were shedding worm eggs. Increasing anti-T. circumcincta IgA antibody and eosinophil concentrations were associated with a reduction in total numbers of adult worms and an increase in the frequency of early L4s. The data also suggest that genetic selection for an enhanced anti-T. circumcincta IgA response might complement selection based on a reduced FEC as a strategy to select for resistance to gastrointestinal nematodes.