Mucosal antibody responses in experimental hookworm infection

Abstract

Hookworms are bloodfeeding nematodes that reside in the intestinal mucosa. These parasites secrete proteins that induce robust systemic immune responses in humans and experimental animals. By contrast, mucosal immune responses in and around the site of attachment are not described as well. This paper presents data from studies aimed at examining hookworm-specific mucosal antibody responses in a hamster model of Ancylostoma ceylanicum infection. Intestinal flush prepared from infected hamsters was analysed by ELISA and shown to be enriched in IgA-specific for A. ceylanicum excretory-secretory (ES) products. Evaluation of mucosal IgA responses by immunoblot demonstrated that infected hamsters recognized a broad range of ES proteins. Hamsters repeatedly exposed to drug-terminated infections were shown to have enhanced serum IgG and mucosal IgA responses, as well as a high level of protection from challenge infection. Parasite-specific IgA was also detected in the faeces of hamsters undergoing a primary infection, and increasing faecal IgA responses were coincident with significant reductions in intestinal worm burdens and faecal ES output over time. Together these results suggest that secretory IgA may act in concert with other components of the mucosal and systemic immune response to promote protective immunity against hookworm infection and/or disease.

Mucosal Antibodies to the C Terminus of Toxin A Prevent Colonization of Clostridium difficile

“…Note that commercial secondary antibodies recognizing hamster SIgA are not currently available, but in our hands, anti-mouse IgA secondary antibody was suitable for the detection of fecal SIgA, as also reported previously (23). Using fecal samples taken 7 days after the final immunization, we were unable to detect SIgA.…”

Epidemiology of Hookworm Infection in Kintampo North Municipality, Ghana: Patterns of Malaria Coinfection, Anemia, and Albendazole Treatment Failure

“…78,79 Also, the observation that levels of IgG correlate with infection status, at least in children, validates the use of A. ceylanicum as a source of potentially relevant hookworm antigens that can be identified based on reactivity with human sera. Because the laboratory model of A. ceylanicum infection recapitulates the clinical features of human hookworm infection, 19,21,80 specific ES antigens recognized by infected individuals may represent valuable targets for human drug and vaccine development.…”

“…Total immunoglobulin G (IgG) antibody levels to A. ceylanicum excretory-secretory (ES) proteins were measured in serum samples from study subjects using a previously described enzyme-linked immunosorbent assay (ELISA). 19,21 Serum samples (diluted 1:200) from study participants were incubated in ES-coated microtiter plate wells for 3 hours at room temperature. After washing, wells were incubated with horseradish peroxidase-conjugated goat antihuman IgG (diluted 1:5,000), and bound IgG was detected by adding ABTS (2,2'-azino-bis(3-ethylbenzthiazoline-6-sulphonic acid)) substrate solution (Sigma, St. Louis, MO).…”

Immunoglobulin and Iron Deficiency Anemia

“…First, the iron deficiency anemia can be due to several etiologies. In case that the anemia is the result from hookworm infestation, the change of the immunoglobulin, especially for immunoglobulin A, should be observed [3]. In the report, there is no complete clarification of the iron deficiency anemia based on the exact etiologies.…”