The emergence of SARS-CoV-2 variants raises concerns of reduced COVID-19 vaccine efficacy. We investigated the humoral immunity in uninfected and previously infected ChAdOx1 nCoV-19, BNT162b2 and CoronaVac vaccinees, who have received complete regimes of vaccines by means of a SARS-CoV-2 surrogate virus blocking test. The ChAdOx1 nCoV-19 (p = 0.0013) and BNT162b2 (p = 0.0005) vaccines induced significant higher blocking activity with longer durability against the Spike (S) protein receptor binding domain (RBD) of wild type SARS-CoV-2 than the CoronaVac vaccine in uninfected vaccinees. Prior infection improved protection in the CoronaVac vaccinees. Subsequent investigation on the breadth of SARS-CoV-2 vaccine-induced antibody blocking responses, revealed that all vaccine platforms cross-protected uninfected vaccinees against all variant of concerns, except Omicron. Prior infection protected the ChAdOx1 nCoV-19 and BNT162b2 vaccinees against Omicron but not CoronaVac vaccinees. Our study suggests that vaccines that induce broader sterilizing immunity are essential to fight against fast-emerging variants.
Less than 80 Sumatran rhinos (SR, Dicerorhinus sumatrensis) are left on earth. Habitat loss and limited breeding possibilities are the greatest threats to the species and lead to a continuous population decline. To stop the erosion of genetic diversity, reintroduction of genetic material is indispensable. However, as the propagation rate of captive breeding is far too low, innovative technologies have to be developed. Induced pluripotent stem cells (iPSCs) are a powerful tool to fight extinction. They give rise to each cell within the body including gametes and provide a unique modality to preserve genetic material across time. Additionally, they enable studying species-specific developmental processes. Here, we generate iPSCs from the last male Malaysian SR Kertam, who died in 2019, and characterize them comprehensively. Differentiation in cells of the three germ layers and cerebral organoids demonstrate their high quality and great potential for supporting the rescue of this critically endangered species.
Similar to other apex predator species, populations of mainland (Neofelis nebulosa) and Sunda (Neofelis diardi) clouded leopards are declining. Understanding their patterns of genetic variation can provide critical insights on past genetic erosion and a baseline for understanding their long-term conservation needs. As a step toward this goal, we present draft genome assemblies for the two clouded leopard species to quantify their phylogenetic divergence, genome-wide diversity, and historical population trends. We estimate that the two species diverged 5.1 Mya, much earlier than previous estimates of 1.41 Mya and 2.86 Mya, suggesting they separated when Sundaland was becoming increasingly isolated from mainland Southeast Asia. The Sunda clouded leopard displays a distinct and reduced effective population size trajectory, consistent with a lower genome-wide heterozygosity and SNP density, relative to the mainland clouded leopard. Our results provide new insights into the evolutionary history and genetic health of this unique lineage of felids.