Intestinal antilectin immunoglobulin A antibody response and immunity to Entamoeba dispar infection following cure of amebic liver abscess.

Abstract

We followed 93 subjects with amebic liver abscess (ALA) and 963 close associate controls at 3-month intervals for 36 months to characterize intestinal and humoral antibody responses to the amebic galactose-inhibitable lectin and to determine whether immunity developed to Entamoeba histolytica or Entamoeba dispar infection following cure of ALA. We found that ALA subjects had a higher prevalence and level of intestinal antilectin immunoglobulin A (IgA) and serum anti-LC3 (cysteine-rich recombinant lectin protein) IgA and IgG antibodies, P < 0.01 and P < 0.05, respectively, compared to controls. The intestinal antilectin IgA antibody response was sustained over a longer time period in ALA subjects (71.8% remained positive at 18 months and 52.6% at 36 months, P < 0.001 compared to 17.6% and 10.3% of controls, respectively). ALA subjects were highly immune to E. dispar infection throughout the study (0% infected at 6 and 36 months, compared to 6.5% and 4.9% of control subjects, respectively, P < 0.05). Upon entry into the study, 6.3% of ALA subjects were infected with E. histolytica; the incidence of new E. histolytica infections in controls (as determined by culture) was too low (1.4%) to determine whether ALA subjects exhibited immunity to new infections. We found that stool cultures every 3 months markedly underestimated the occurrence of new E. histolytica infections, as 15.3% of controls seroconverted after 12 months of follow-up. Unfortunately, under the field conditions present in Durban, South Africa, enzyme-linked immunosorbent assay for detection of lectin antigen in stool yielded unreliable results. In summary, subjects cured of ALA exhibited sustained mucosal IgA antibody responses to the amebic galactose-inhibitable lectin and a high level of immunity to E. dispar infection. Determination of immunity to E. histolytica following cure of ALA will require the use of more sensitive and reliable diagnostic methods.

• Authors: Jonathan I Ravdin, Mohamed D Abd-Alla, Seth L Welles, Selvan Reddy, Terry F H G Jackson
• Journal: Infection and immunity (Infect Immun) Vol. 71 Issue 12 Pg. 6899-905 (Dec 2003) ISSN: 0019-9567 [Print] United States
• PMID: 14638778 (Publication Type: Journal Article, Research Support, Non-U.S. Gov't, Research Support, U.S. Gov't, P.H.S.)

Chemical References

• Antibodies, Protozoan
• Immunoglobulin A, Secretory
• Immunoglobulin G
• Lectins
• Membrane Glycoproteins
• Protozoan Proteins
• galactose inhibitable adherence protein, Entamoeba histolytica

Topics

• Adult
• Animals
• Antibodies, Protozoan (blood)
• Cohort Studies
• Entamoeba (immunology)
• Entamoeba histolytica (immunology)
• Entamoebiasis (epidemiology, immunology, parasitology)
• Feces (parasitology)
• Female
• Humans
• Immunoglobulin A, Secretory (analysis, blood)
• Immunoglobulin G (blood)
• Intestines (immunology)
• Lectins (immunology)
• Liver Abscess, Amebic (therapy)
• Male
• Membrane Glycoproteins (immunology)
• Prospective Studies
• Protozoan Proteins (immunology)