The D-form of a novel heparan binding peptide decreases cytomegalovirus infection in vivo and in vitro

Abstract

Human cytomegalovirus (HCMV) infection in utero can lead to congenital sensory neural hearing loss and mental retardation. Reactivation or primary infection can increase the morbidity and mortality in immune suppressed transplant recipients and AIDS patients. The current standard of care for HCMV disease is nucleoside analogs, which can be nephrotoxic. In addition resistance to current treatments is becoming increasingly common. In an effort to develop novel CMV treatments, we tested the effectiveness of the D-form of a novel heparan sulfate binding peptide, p5RD, at reducing infection of ganciclovir (GCV) resistant HCMVs in vitro and MCMV in vivo. HCMV infection was reduced by greater than 90% when cells were pretreated with p5RD. Because p5RD acts by a mechanism unrelated to those used by current antivirals, it was effective at reducing GCV resistant HCMVs by 85%. We show that p5RD is resistant to common proteases and serum inactivation, which likely contributed to its ability to significantly reduced infection of peritoneal exudate cells and viral loads in the spleen and the lungs in vivo. The ability of p5RD to reduce HCMV infectivity in vitro including GCV resistant HCMVs and MCMV infection in vivo suggests that this peptide could be a novel anti-CMV therapeutic.

Precision mouse models with expanded tropism for human pathogens

“…LoM and BLT-L mice were inoculated with HCMV TB40/E expressing luciferase 45 . HCMV replication was detectable in the human lung implants of LoM and BLT-L mice at 4 d postinoculation (Fig.…”

“…For the AD169 time course experiment in LoM, human lung implants were collected at days 4 (n = 2 mice, 3 human lung implants), 7 (n = 2 mice, 4 human lung organoids), 14 (n = 2 mice, 4 human lung implants), 21 (n = 2 mice, 4 human lung implants) and 28 (n = 2 mice, 4 human lung implants) postexposure and data represent one experiment. To evaluate HCMV replication over time in human lung implants, HCMV TB40/E expressing luciferase (4.25 × 10 5 TCID 50 ) 45 was inoculated into the human lung implants of human donor matched LoM (n = 3 mice, 6 human lung implants) and BLT-L mice (n = 3 mice, 6 human lung implants). Luciferase expression was measured on anesthetized mice with an IVIS Lumina Optical System following intraperitoneal injection of D-Luciferin (15 mg kg −1 ) on days 4, 7, 11 and 14 and weeks 4 and 5 following HCMV exposure.…”

“…HCMV production and infection of mice. Anesthetized LoM and BLT-L mice were exposed to HCMV by direct injection of HCMV TB40/E (4.25 × 10 5 -6 × 10 6 TCID 50 ) 45,71 , ADrUL131 (2.4 × 10 5 TCID 50 ) 48 or AD169 (1.1-6 × 10 6 TCID 50 ) 72 into the human lung implants. For the TB40/E time course experiment in LoM, human lung implants were collected at days 4 (n = 2 mice, 4 human lung implants), 7 (n = 2 mice, 4 human lung organoids), 14 (n = 3 mice, 5 human lung implants) and 21 (n = 2 mice, 3 human lung implants) postexposure and data represent one experiment.…”

“…2l represents an additional LoM. For the GCV preexposure prophylaxis experiment, LoM (n = 3 mice, 6 human lung implants) were administered 100 mg kg −1 GCV daily for 17 d by intraperitoneal injection and inoculated with HCMV TB40/E expressing luciferase (4.25 × 10 5 TCID 50 ) 45 after…”

Mouse Cytomegalovirus Differentially Exploits Cell Surface Glycosaminoglycans in a Cell Type-Dependent and MCK-2-Independent Manner

“…This has led to the design of new anti-heparan sulfate peptides to mask cell surface anchor points for the virus [38]. Although they are very efficient in blocking infection by both HCMV and MCMV in vitro, these peptides are only partially protective in vivo [39,40]. Since most previous reports on the role of surface GAGs in viral entry studied a limited variety of target cell types (typically fibroblasts or epithelial cells in the case of HCMV) [34,41], lack of in vivo efficacy by anti-HS peptides could result if HCMV and MCMV interacted with cell type-specific GAGs differentially expressed on different types of target cells.…”