Ricerc@Sapienza

INTRODUCTION The gastrointestinal tract is a major site of HIV localization and even
though cART (combined AntiRetroviral Therapy) leads to suppression of HIV replication
the gastrointestinal pathology is still persistent. In these patients increased levels of inflammation
and decreased levels of mucosal repair and regeneration are observed. Consequently
novel directions for dietary and therapeutic interventions that restore the immunological
and epithelial integrity of the mucosal barrier are needed. Since HIV infected patients host
in their gut a prevalence of several detrimental bacterial populations, attempts to modify
their gut flora with probiotics is justified. PATIENTS and METHODS Ten subjects receiving
combined antiretroviral therapy for HIV-1 were treated for 6 months with multistrain
probiotic formulation containing Lactobacillus plantarum DSM24730, Streptococcus thermophilus
DSM24731, Bifidobacterium breve DSM24732, L. paracasei DSM24733, L. delbrueckii subsp.
bulgaricus DSM24734, L. acidophilus DSM 24735, B. longum DSM24736, B. infantis DSM24737
(Vivomixx in EU, Visbiome in USA). At baseline and 6 months, IELs density and enterocytes
death via apoptosis as well as mitochondrial morphology were analyzed by immunoistichemical.
Faecal water samples (FWS) were collected at T0 and after 6 month of probiotics
treatment and checked for antiviral activity. RESULTS We observed the recovery of the
integrity of the gut epithelial barrier by reducing IELs density and enterocytes death via
apoptosis as well as mitochondrial morphology. This was associated to an improvement of
quality of life. As compared to control, faecal water from patients treated with this specific
formulation reduced viral replication in treated cells (C8166 cells, infected with T-cell tropic
strain HIV-1 P1 at multiplicities of infection (MOIs) of 0.05 TCID50/ml for 1 hour at 37°C),
both at 24h and 48h. The antiviral activity of faecal water from patients treated with probiotics
for 6 months (T6 FWS) resulted higher than T0 (38% +/- 10) with a percentage of inhibition
of 68% (+/- 24) at 24 hours, further confirmed by the results at 48h where percentage of
inhibition of more than 90% was recorded. CONCLUSIONS Our results confirm the gut
flora plays a role in the interactions host-HIV also in terms of resistance to the HIV infection
and the benefits of this specific probiotic preparation for the amelioration of the intestinal
inflammation of cART patients. However, not all the probiotic formulation are equally suited
for HIV patients as previously reported therefore our data should not be extrapolated to
other untested probiotic products.