Interaction between calcineurin inhibitors and IL-28B rs12979860 C>T polymorphism and response to treatment for post-transplant recurrent hepatitis C.

BACKGROUND: The impact of calcineurin inhibitors on achievement of sustained virological response to antiviral therapy for post-transplant recurrent hepatitis C is controversial. This study aimed at investigating the interactions between calcineurin inhibitors and interleukin-28B (IL-28B) gene polymorphisms and sustained virological response. METHODS: Retrospective study of 147 liver transplant recipients with recurrent hepatitis C, who received 48 weeks of peg-interferon-α (N=113) or standard interferon (N=34), in association with ribavirin. Cyclosporine and tacrolimus were administered in 68 and 79 patients, respectively. IL-28B rs12979860 allele frequency was assessed in both donors and recipients. RESULTS: Overall, 57 patients (38.8%) obtained sustained virological response; no difference was found between cyclosporine and tacrolimus-treated patients (42.6% vs. 35.4%, p=0.371). Recipient and donor IL-28B genotypic frequencies were C/C=30.6%, C/T=51.7%, T/T=17.7% and C/C=44.9%, C/T=50.3%, T/T=4.8%, respectively. Combining donor and recipient alleles, response rates decreased from cyclosporine-treated patients carrying ≤ 1 T allele (56.1%) to tacrolimus-treated patients carrying ≤ 1 T allele (44.7%) to patients carrying ≥ 2 T alleles (25.0%, p=0.0009). CONCLUSIONS: Donor and recipient rs12979860 alleles synergistically influence sustained virological response rate to antiviral treatment for recurrent hepatitis C. In patients carrying <2 T alleles cyclosporine favours a better response than tacrolimus, while no difference was found in the presence of ≥ 2 T alleles.

Description and molecular modeling of a novel human leukocyte antigen allele: A*32:22.

We describe here the sequence and the molecular modeling of a new variant of HLA-A*32 allele officially named A*32:22. This novel allele has been detected in an Italian cord blood sample by sequence-based typing (SBT). The mutation (CAT →CGT), which has occurred at codon 151, at nucleotide position 524, implies an amino acidic change from Histidine to Arginine. Residue 151 is located on top of the molecule inside the region contacted by T cell receptor (TCR) and it is possibly involved in docking TCR. A positively charged residue is maintained on this position determining a slight change of electrostatic potential on the molecular surface. This suggests a limited functional relevance of the amino acid substitution encoded by A*32:22.

Three novel alleles at the HLA-DRB1 locus identified by sequence-based typing.

We describe here the sequences of 3 new HLA-DRB1 variants officially named DRB1*03:05:03, DRB1*11:10:02, and DRB1*14:86. These novel alleles have been detected in 3 Caucasoid individuals by sequence-based typing. The first and second alleles are the result of a silent mutation, which does not imply any amino acid change. The sequence of DRB1*14:86 exhibits a single nucleotide difference with the allele DRB1*14:01:01 at position 239.

Stimulation of TLRs by LMW-HA induces self-defense mechanisms in vaginal epithelium.

The innate immune system is present throughout the female reproductive tract and functions in synchrony with the adaptive immune system to provide protection in a way that enhances the chances for fetal survival, while protecting against potential pathogens. Recent data show that activation of Toll-like receptor (TLR)2 and 4 by low-molecular weight hyaluronic acid (LMW-HA) in the epidermis induces secretion of the antimicrobial peptide ß-defensin 2. In the present work, we show that LMW-HA induces vaginal epithelial cells to release different antimicrobial peptides, via activation of TLR2 and TLR4. Further, we found that LMW-HA favors repair of vaginal epithelial injury, involving TLR2 and TLR4, and independently from its classical receptor CD44. This wound-healing activity of LMW-HA is dependent from an Akt/phosphatidylinositol 3 kinase pathway. Therefore, these findings suggest that the vaginal epithelium is more than a simple physical barrier to protect against invading pathogens: on the contrary, this surface acts as efficient player of innate host defense, which may modulate its antimicrobial properties and injury restitution activity, following LMW-HA stimulation; this activity may furnish an additional protective activity to this body compartment, highly and constantly exposed to microbiota, ameliorating the self-defense of the vaginal epithelium in both basal and pathological conditions.

Low dose oral administration of cytokines for treatment of allergic asthma.

Many inflammatory diseases are characterized by an imbalance among lymphocyte populations, in particular Th1, Th2 and the recently described Th17 cells. The Th1/Th2 imbalance is linked to many factors, but certainly the role of cytokines is essential. In Th2 diseases IL-4 expression is predominant, while Th1 pathologies are characterized by high expression of IFN-gamma and IL-12. Though today the therapeutical proposal for many inflammatory diseases aims to re-establish normal levels of Th1/Th2 cytokines, the pharmacological use of cytokines, which are very active molecules, is limited by the possible collateral effects. Therefore, our study aims to determine, in a murine model of allergic asthma, the possible therapeutic activity of low dose cytokines solutions, mechanically activated. We found that oral administration of low doses IL-12 plus IFN-gamma is able to solve the bronchial hyperresponsiveness condition of mice, establishing normal cytokine levels. The anti-asthma activity was confirmed by histological analysis of lungs and broncho-alveolar lavage fluid cell count. Serum ovalbumin-specific IgE was also significantly inhibited by treatment with low dose activated cytokines solution. These findings may suggest a novel approach to diseases which involve a Th1/Th2 imbalance.