Reduced Plasma Levels of sCD14 and I-FABP in HIV-infected Patients with Mesalazine-treated Ulcerative Colitis

Abstract

Background: Microbial translocation (MT) is a shared feature of HIV infection and inflammatory bowel disease (IBD). Aims: This study was conducted to assess the impact of IBD (and particularly ulcerative colitis, UC) on plasma markers of MT and immune activation in HIV+ subjects.

Methods: A cross-sectional study was conducted in 3 groups of patients: HIV+/UC+(group HIV/UC); HIV+/UC- (group HIV); HIV-/UC+(group UC). Plasma levels of soluble CD14 (sCD14), intestinal fatty acid-binding protein (I-FABP), and endotoxin core antibodies (endoCAB) were measured as plasma markers of MT. Inflammation and immune activation were evaluated by measuring plasma levels of IL-6, IL-21, TNF-alpha, and high-sensitivity C-reactive protein (hs-CRP). T- and B-cells subpopulations were characterized by FACS analysis.

Results: Seven patients were enrolled in group HIV/UC, 9 in HIV, and 10 in UC. All HIV-positive patients had plasma values of HIV-1 RNA < 37 copies/mL for at least 12 months and good immunological recovery. All patients with UC were treated with oral mesalazine. Markers of MT, immune activation, and inflammation were not increased in subjects with HIV/UC. In fact, they had lower levels of I-FABP (p = 0.001) and sCD14 (p = 0.007) when compared to other patients groups. Positive correlations were found between I-FABP and sCD14 (r = .355, p = 0.076). Frequency of T- and B-cell subsets did not differ among groups.

Conclusions: Our results suggest that UC does not worsen MT, inflammation, or immune activation in HIV-infected subjects. The anti-inflammatory activity of chronic mesalazine administration on intestinal mucosa may contribute to this finding.

Key words:

• Microbial translocation
• HIV infection
• Inflammatory bowel disease
• Ulcerative colitis
• Soluble CD14

Acknowledgments

We thank Mrs. Stefania Donnini for secretarial help. We are grateful to Dr. PG Pupino Carbonelli for hematological analysis. We thank Patrizia Cocco and Ferdinando Costa for technical support and all the patients participating in this study.