Decay of antibody isotypes against early developmental stages of Schistosoma mansoni after treatment of schistosomiasis patients

Abstract

Antibodies to a number of parasite antigens are found in schistosomiasis patients, and antibodies to early developmental stages were demonstrated to be efficient immunologic markers for the diagnosis of schistosomiasis. In the present study, decay patterns of IgM and IgG antibodies against cercariae and schistosomula were investigated, in comparison to antibodies against worms and eggs in schistosomiasis patients after chemotherapy, for an investigation of seroepidemiologic aspects. Data obtained in the study of 359 serum samples from patients with Schistosoma mansoni infection, noninfected individuals, and patients followed-up for a period of 12 to 15 months after treatment provided the basis to postulate a general pattern for the kinetics of antibody decay. Before treatment, the antibody pattern was represented by a unimodal curve, which shifted to a bimodal curve after treatment, and ended with a unimodal curve similar to that for the noninfected group. Different types of antibodies were classified into four categories according to their decay features, and anti-schistosomulum IgM was classified into the moderate-decay category, whereas other antibodies to early parasite stages were classified into the slow-decay category. The present methodology permits the identification of the most suitable antibodies to be detected in field control programs for schistosomiasis or other parasitoses.

Decreasing Intestinal Parasites in Recent Northern California Refugees

“…17,18 However, repeated serology testing after some time has elapsed could help clarify the diagnosis, perhaps even for Schistosoma infection as scientists develop newer assays for antibodies that wane with time after treatment. [19][20][21][22] The presence of eosinophilia may help confirm infection with positive serology, though because it is often transient and rarely found, its absence cannot exclude infection.…”

Detection of specific antibody isotypes and subtypes before and after treatment of American visceral leishmaniasis

“…In population surveys, easy methods to evaluate the treatment efficacy are required. We adopted here a model that was proposed for an unrelated parasitic infection (24), by plotting antibody titers against their frequencies. In the successful treatment, three different types of curves were consecutively observed: the unimodal curve (1), which is typical for the period before treatment, changes to a bimodal curve (2) after treatment in account of the antibody titer decays and seroconversions to negative, and becomes unimodal (3) again similar to that presented by an uninfected group of individuals.…”

Schistosomiasis mansoni: follow-up of control program based on parasitologic and serologic methods in a Brazilian community of low endemicity

“…It is a well known fact that immediately after chemotherapy, the levels of specific antibodies rise stimulated by the death of the parasites and fall soon after. They may disappear within 6 to 12 months or after a period 5 years, depending on the technique and antigen used (Noya et al 1992, Kanamura et al 1997. Among 198 IgM positive residents in Pedro de Toledo, in 1998, 14 were identified as having been previously treated with oxamniquine.…”