T4 bacteriophage-mediated inhibition of adsorption and replication of human adenovirus in vitro.

AIM: The objective of this study was to evaluate the effects of T4 phage on adsorption and replication of human adenovirus (HAdV). MATERIALS & METHODS: Experiments were performed on cell lines A549 and HEK-293. Intracellular HAdV virions were released and titrated by Reed-Muench method. RESULTS: T4 significantly (p < 0.05) inhibited both the adsorption of HAdV and viral replication in a dose-dependent manner. Mean reductions in HAdV titer were within the range 0.634-2.12 and 0.238-1.88 log10 TCID50/ml for HAdV adsorption and replication, respectively. CONCLUSION: T4 phage can inhibit infections by HAdV-5 of target cells. Our results suggest that T4 might be considered a novel agent against HAdV and possibly other pathogenic viruses. Potential antiviral effects of other phages should also be investigated.

New alloferon analogues: synthesis and antiviral properties.

We have extended our study on structure/activity relationship studies of insect peptide alloferon (H-His-Gly-Val-Ser-Gly-His-Gly-Gln-His-Gly-Val-His-Gly-OH) by evaluating the antiviral effects of new alloferon analogues. We synthesized 18 alloferon analogues: 12 peptides with sequences shortened from N- or C-terminus and 6 N-terminally modified analogues H-X(1)-Gly-Val-Ser-Gly-His-Gly-Gln-His-Gly-Val-His-Gly-OH, where X(1) = Phe (13), Tyr (14), Trp (15), Phg (16), Phe(p-Cl) (17), and Phe(p-OMe) (18). We found that most of the evaluated peptides inhibit the replication of Human Herpesviruses or Coxsackievirus B2 in Vero, HEp-2 and LLC-MK(2) cells. Our results indicate that the compound [3-13]-alloferon (1) exhibits the strongest antiviral activity (IC(50) = 38 µM) among the analyzed compound. Moreover, no cytotoxic activity against the investigated cell lines was observed for all studied peptides at concentration 165 µM or higher.

Further studies on the antiviral activity of alloferon and its analogues.

The subject of our studies was the synthesis, biological evaluation, and conformational studies of insect tridecapeptide alloferon (H-His-Gly-Val-Ser-Gly-His-Gly-Gln-His-Gly-Val-His-Gly-OH) and its analogues such as: [des-His(1) ]-, [Lys(1) ]-, [Arg(1) ]-, and [Ala(1) ]-alloferon. These peptides were synthesized to check the influence of the His residue at position 1 of the alloferon chain on its antiviral activity. Two aspects of the biological effects of these peptides were determined: (i) the cytotoxicity in vitro in the Vero, LLC-MK2, and HEp-2 cell lines, and (ii) the antiviral activity in vitro in respect to DNA and RNA viruses. We found that alloferon inhibited the herpes virus multiplication and failed to affect the coxsackie virus replication, whereas [Lys(1) ]-alloferon exhibited a high inhibitory action towards both viruses. Moreover, the peptides did not show any cytotoxic activity against the Vero, LLC-MK2, and HEp-2 cells. The preliminary circular dichroism conformational studies showed that the peptides investigated seem to prefer an unordered conformation.

Studies of insect peptides alloferon, Any-GS and their analogues. Synthesis and antiherpes activity.

The subject of these studies was synthesis and determination of biological properties of a series of insect peptides, such as alloferon, Any-GS and their analogues. The synthesis of 14 peptides was performed by the solid-phase method. Biological effect of these peptides was evaluated by the antiviral test against Human Herpes Virus type 1 (HHV-1) in vitro using a Vero cell line. It was found that the investigated peptides inhibit the replication of HHV-1 in Vero cells.