Differential PCDH1 usage by Laguna Negra and Black Creek Canal hantaviruses

Laguna Negra virus and Black Creek Canal virus are hantaviruses associated with hantavirus cardiopulmonary syndrome (HCPS), but their cellular entry receptors have not been defined. We used replication-competent recombinant vesicular stomatitis viruses (rVSVs) bearing hantavirus Gn/Gc glycoprotein complexes to compare entry by these viruses, the Old World rodent-borne Dabieshan virus and Tigray virus, and the shrew-borne Cao Bang virus and Amga virus. All six Gn/Gc complexes supported infection of primary human pulmonary microvascular endothelial cells, with virus-specific efficiencies and kinetics. Genetic ablation of protocadherin-1 (PCDH1) reduced infection mediated by Laguna Negra virus and Black Creek Canal virus Gn/Gc in human osteosarcoma and endothelial cells, whereas PCDH1 re-expression restored susceptibility. Both viruses were captured by a soluble PCDH1 protein comprising the first two extracellular cadherin domains. Infection was also inhibited by a soluble decoy containing the first cadherin domain, and by an antibody specific to that domain, indicating that the first PCDH1 cadherin domain mediates viral engagement. Black Creek Canal Gn/Gc-bearing rVSVs incorporated less Gn/Gc and showed lower apparent capture by PCDH1 than Laguna Negra virus and Andes virus Gn/Gc-bearing particles, even after normalization for glycoprotein abundance. In contrast, PCDH1 depletion did not detectably alter infection mediated by the other four hantavirus Gn/Gc complexes. Thus, Laguna Negra virus and Black Creek Canal virus use PCDH1 for efficient entry but differ in apparent receptor engagement and responses to PCDH1-directed inhibitors, whereas all six viruses are potently neutralized by the broadly reactive Gn/Gc-directed antibody ADI-42898.

The receptors used by many medically important hantaviruses remain incompletely characterized. Using BSL2-compatible rVSVs bearing hantavirus glycoproteins, we show that Laguna Negra virus and Black Creek Canal virus, two hantaviruses associated with human cardiopulmonary disease, used protocadherin-1 (PCDH1) for efficient entry into human cells. PCDH1-directed inhibitors blocked infection, but the two viruses differed in apparent receptor engagement and inhibitor sensitivity, showing that PCDH1 usage is not uniform even among closely related viruses. Gn/Gc complexes from four additional divergent hantaviruses carried by shrews and Old World rodents infected primary human endothelial cells without detectable PCDH1 dependence, emphasizing the need to identify alternative entry factors. A broadly reactive antibody neutralized every virus in the study panel, supporting conserved viral glycoprotein surfaces as therapeutic targets when receptor usage is diverse or unknown.