use of ELISA and immunohistochemistry techniques for detection of toxoplasma gondii antigen in tissues of experimentally infected mice

The capability of double antibody sandwich enzyme-linkad immunosorbent assay [ELISA] for detecting antigens of Toxoplasma gondii [T. gondii] in different mice tissue specimens was evaluated in comparison to the immunohistochemistry [IHC] technique. Results proved that tissue antigens were detectable in liver, kidney and mesenteric lymph node [LN] specimens by both methods from the second day of infection, with statistically significant increase in its amount in all organs throughout the period of the study. Using ELISA technique, the highest antigen level was recorded on the second day [0.120 +/- 0.0015] and the fourth day [0.147 +/- 0.0034] of infection in LN specimens, while, the liver showed the highest antigen level at the sixth day post infection [PI][0.165 +/- 0.0066]. On the other hand, using the IHC technique, the highest number of tachyzoites was recorded in LN sections in all studied durations, the second, the fourth and the sixth days PI [1.1 +/- 0.875, 1.6 +/- 1.173 and 3.1 +/- 1.370 respectively]. Thus, sandwich ELISA technique might offer a valuable aid for rapid diagnosis of acute toxoplasmosis in human tissues, and it has proved to be more accurate than IHC technique, since its results was coincided with the pathogenesis of the disease.

immune response in ascariasis

Thirty patients infected with Ascaris lumbricoides and 10 parasite free matched controls formed the subject of this study. Their ages ranged from 5 to 50 years. Patients were categorized according to the intensity of infection into 3 groups [A, B and C]. Haemoglobin percentage, total and differential leucocytic counts as well as absolute eosinophilic count were determined for cases and controls. Immunoglobulins G, A and M were quantitated in serum and fresh faecal extracts by single radial immunodiffusion. Anaemia was present in all patients. Absolute eosinophilic count was significantly increased in groups A and B, but the correlation between it and egg count was statistically not significant. A significant increase of serum IgG and significant diminution of secretory IgA was detected in all infected groups. From the obtained data it was deduced that the magnitude of the antibody response in ascariasis is not necessarily related to the parasite load

Specific anti-giardia antibodies in human milk and their protective role

Indirect immunofluorescent testing [IFAT] was performed to detect the presence of anti-Giardia antibodies [IgG and IgA] in the serum and milk of 20 lactating giardiasis mothers and 20 parasite free matched controls, using faecal cyst antigen. The prevalence of giardiasis among infants of parasite free mothers was significantly higher [75%] than among infants of giardiasis mothers [15%]. It was significantly higher in those above 1 year [89.47,%] than in those below 1 year [23.80%]. Milk antibodies were a better reflection of infection than serum antibodies [were 100% and 90% positivity respectively]. All controls gave negative results. A significant negative relation was present between the specific serum IgG antibody as well as specific IgA and IgG antibodies in immune mother's milk and the prevalence of giardiasis in their infants suggesting their significant role in infant's protection; on condition that the infant receives 5 or more breast feeds per day

study of serum and secretory immunoglobulins in children infected with giardia lamblia

Quantitive estimation of immunoglobulins C, A and M in serum extracts was carried out by single radial immunodiffusion in 30 children infescted with Giardia only [15 symptomatic and 15 asymptomatic] and 10 parasite free matched controls. There were no statistically significant differences between symptomatic asymptomatic, and control groups as regards serum immunoglobulins G, A and M. In the symptomatic group, intestinal IgA and IgM levels were significantly higher than those of eithen control or asymptomatic group. Whereas, intestinal IgG level in the symptomatic group was significant only when compared to the asymptomatic group. This increase was more obvious in the older age group and in those with acute symptoms