|Title / Titel||Humoral immune response to gastrointestinal bacteria as a potential read-out for microbial translocation during late-stage HIV-1 infection|
|Abstract (PDF, 14 KB)|
|Summary / Zusammenfassung||Background: Systemic immune activation and depletion of CD4 T lymphocytes are hallmarks of chronic HIV-1 infection. Microbial translocation due to a disrupted intestinal barrier has recently been suggested to contribute to chronic immune activation1. Increased levels of LPS in the plasma of chronically infected HIV-1 and AIDS patients were measured as a read-out for microbial translocation in this study.
Indeed, increased intestinal permeability during the late chronic phase of HIV-1 infection was already reported in the 1990s 2-4. Additionally, elevated levels of bacterial butyrate have been measured in the urine of HIV-1 patients as an indicator of increased microbial translocation from the gut 5.
Study Aims: Further analysis of the impact of microbial translocation on the immune system during HIV-1 infection is currently lacking. In this context we aim to study systemic humoral responses against intestinal microbiota during chronic HIV-1 infection as a read-out for systemic microbial translocation. We will measure longitudinal changes in enteric microbiota-specific ab-levels of the IgG, IgA and IgM isotypes in patients with advanced disease. Potential changes will be correlated with respective plasma LPS levels.
Study Design: Based on a flow cytometric approach we will measure (1) IgG , (2) IgA and (3) IgM-responses against intestinal as well as other commensal bacteria in serum or plasma samples.
We will analyze these responses in longitudinal samples of progressing late stage HIV-1 patients. The same samples will be screened in parallel for levels of LPS as an additional read-out for microbial translocation1. Patients will be recruited according to the following diagnosis: (1) Cryptosporidiosis, (2) pathogen-free diarrhea or (3) without any reported gastrointestinal problems.
|Keywords / Suchbegriffe||HIV, antibodies, diarrhea, LPS|
|Project leadership and contacts /
Projektleitung und Kontakte
|Funding source(s) /
|SNF (Personen- und Projektförderung)
Swiss HIV Cohort Study
|Duration of Project / Projektdauer||Apr 2009 to Mar 2012|