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Lactoferrin (LF) is a multifunctional glycoprotein, which plays an important role in immune regulation and defense mechanisms against bacteria, fungi, and viruses. Lactoferricin (Lfcin) is a potent antimicrobial peptide generated from the N-terminal part of LF by pepsin cleavage. In this study, we investigated the mechanisms of the anti-herpes simplex virus (anti-HSV) activity of LF and Lfcin. The results demonstrated that LF and Lfcin inhibited the entry of HSV into Vero cells. LF had no effect against HSV after the virus had entered the cells, while Lfcin exerted antiviral activity also after the initial binding of the virus to the host cell. The distribution of LF and Lfcin in the cells was investigated by immunogold-labeling and transmission electron microscope (TEM). LF was found mainly at the cell surface in cells expressing heparan sulphate. Lfcin was randomly distributed intracellularly. LF must be present at the cell surface to exert antiviral activity, while Lfcin exert its antiviral activity also when found mainly intracellularly. Both LF and Lfcin were dependent on the presence of heparan sulphate at the cell surface to exert their antiviral activity.

In sub-Saharan Africa, most new HIV infections occur in stable relationships, making couples testing an important intervention for HIV prevention. We explored factors shaping the decision-making of cohabiting couples who opted to self-test in Blantyre, Malawi. Thirty-four self-tested participants (17 couples) were interviewed. Motivators for HIV self-testing (HIVST) emerged at three main levels. Individual motivations included perceived benefits of access to treatment, and self-checking of serostatus in the hope of having been cured by prolonged treatment or faith-healing. HIVST was considered convenient, confidential, reassuring and an enabling new way to test with one’s partner. Partnership motivations included both positive (mutual encouragement) and negative (suspected infidelity) aspects. For women, long-term health and togetherness were important goals that reinforced motivations for couples testing, whereas men often needed persuasion despite finding HIVST more flexible and less onerous than facility-based testing. Internal conflict prompted some partners to use HIVST as a way of disclosing their previously concealed HIV positive serostatus. Thus, the implementation of community-based HIVST should acknowledge and appropriately respond to decision-making processes within couples, which are shaped by gender roles and relationship dynamics.

The human polyomavirus BK (BKV) causes nephropathy and hemorrhagic cystitis in kidney and bone marrow transplant patients, respectively. The anti-viral cidofovir (CDV) has been used in small case series but the effects on BKV replication are unclear, since polyomaviruses do not encode viral DNA polymerases. We investigated the effects of CDV on BKV(Dunlop) replication in primary human renal proximal tubule epithelial cells (RPTECs). CDV inhibited the generation of viral progeny in a dose-dependent manner yielding a 90% reduction at 40 lg/mL. Early steps such as receptor binding and entry seemed unaffected. Initial large T-antigen transcription and expression were also unaffected, but subsequent intra-cellular BKV DNA replication was reduced by >90%. Late viral mRNA and corresponding protein levels were also 90% reduced. In uninfected RPTECs, CDV 40 lg/mL reduced cellular DNA replication and metabolic activity by 7% and 11% in BrdU and WST-1 assays, respectively. BKV infection increased DNA replication to 142% and metabolic activity to 116%, respectively, which were reduced by CDV 40 lg/mL to levels of uninfected untreated RPTECs. Our results show that CDV inhibits BKV DNA replication downstream of large T-antigen expression and involves significant host cell toxicity. This should be considered in current treatment and drug development.

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The immunomodulatory drug leflunomide is frequently used for treating polyomavirus-associated nephropathy, yet its antiviral mechanism is unclear. We characterized the effects of the active leflunomide metabolite A771726 (LEF-A) on the polyomavirus BK (BKV) life cycle in human renal tubular epithelial cells. LEF-A at 10 g/ml reduced the extracellular BKV load by 90% (IC 90 ) but with significant host cytostatic effects. BKV genome replication, late protein expression, and virion assembly and release were inhibited with visible disruption of the nuclear replication architecture. Both host cell and antiviral effects were largely reversed by uridine addition, implicating nonspecific pyrimidine depletion as the major anti-BKV mechanism of leflunomide.

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