Shotgun transcriptome, spatial omics, and isothermal profiling of SARS-CoV-2 infection reveals unique host responses, viral diversification, and drug interactions

In less than nine months, the Severe Acute Respiratory Syndrome Coronavirus 2 (SARS-CoV-2) killed over a million people, including >25,000 in New York City (NYC) alone. The COVID-19 pandemic caused by SARS-CoV-2 highlights clinical needs to detect infection, track strain evolution, and identify biomarkers of disease course. To address these challenges, we designed a fast (30-minute) colorimetric test (LAMP) for SARS-CoV-2 infection from naso/oropharyngeal swabs and a large-scale shotgun metatranscriptomics platform (total-RNA-seq) for host, viral, and microbial profiling. We applied these methods to clinical specimens gathered from 669 patients in New York City during the first two months of the outbreak, yielding a broad molecular portrait of the emerging COVID-19 disease. We find significant enrichment of a NYC-distinctive clade of the virus (20C), as well as host responses in interferon, ACE, hematological, and olfaction pathways. In addition, we use 50,821 patient records to find that renin-angiotensin-aldosterone system inhibitors have a protective effect for severe COVID-19 outcomes, unlike similar drugs. Finally, spatial transcriptomic data from COVID-19 patient autopsy tissues reveal distinct ACE2 expression loci, with macrophage and neutrophil infiltration in the lungs. These findings can inform public health and may help develop and drive SARS-CoV-2 diagnostic, prevention, and treatment strategies.

Shotgun Transcriptome and Isothermal Profiling of SARS-CoV-2 Infection Reveals Unique Host Responses, Viral Diversification, and Drug Interactions

The Severe Acute Respiratory Syndrome Coronavirus 2 (SARS-CoV-2) has caused thousands of deaths worldwide, including >18,000 in New York City (NYC) alone. The sudden emergence of this pandemic has highlighted a pressing clinical need for rapid, scalable diagnostics that can detect infection, interrogate strain evolution, and identify novel patient biomarkers. To address these challenges, we designed a fast (30-minute) colorimetric test (LAMP) for SARS-CoV-2 infection from naso/oropharyngeal swabs, plus a large-scale shotgun metatranscriptomics platform (total-RNA-seq) for host, bacterial, and viral profiling. We applied both technologies across 857 SARS-CoV-2 clinical specimens and 86 NYC subway samples, providing a broad molecular portrait of the COVID-19 NYC outbreak. Our results define new features of SARS-CoV-2 evolution, nominate a novel, NYC-enriched viral subclade, reveal specific host responses in interferon, ACE, hematological, and olfaction pathways, and examine risks associated with use of ACE inhibitors and angiotensin receptor blockers. Together, these findings have immediate applications to SARS-CoV-2 diagnostics, public health, and new therapeutic targets.

Contribution of human osteoblasts and macrophages to bone matrix degradation and proinflammatory cytokine release after exposure to abrasive endoprosthetic wear particles

One of the major reasons for failure after total joint arthroplasty is aseptic loosening of the implant. At articulating surfaces, defined as the interface between implant and surrounding bone cement, wear particles can be generated and released into the periprosthetic tissue, resulting in inflammation and osteolysis. The aim of the present study was to evaluate the extent to which osteoblasts and macrophages are responsible for the osteolytic and inflammatory reactions following contact with generated wear particles from Ti-6Al-7Nb and Co-28Cr-6Mo hip stems. To this end, human osteoblasts and THP-1 monocytic cells were incubated with the experimentally generated wear particles as well as reference particles (0.01 and 0.1 mg/ml) for 48 h under standard culture conditions. To evaluate the impact of these particles on the two cell types, the release of different bone matrix degrading matrix metalloproteinases (MMPs), tissue inhibitors of MMPs (TIMPs), and relevant cytokines were determined by multiplex enzyme-linked immunosorbent assays. Following incubation with wear particles, human osteoblasts showed a significant upregulation of MMP1 and MMP8, whereas macrophages reacted with enhanced MMP3, MMP8 and MMP10 production. Moreover, the synthesis of TIMPs 1 and 2 was inhibited. The osteoblasts and macrophages also responded with modified expression of the inflammatory mediators interleukin (IL)-6, IL-8, monocyte chemoattractant protein-1 and vascular endothelial growth factor. These results demonstrate that the release of wear particles affects the release of proinflammatory cytokines and has a negative impact on bone matrix formation during the first 48 h of particle exposure. Human osteoblasts are directly involved in the proinflammatory cascade of bone matrix degradation. The simultaneous activation and recruitment of monocytes/macrophages boosted osteolytic processes in the periprosthetic tissue. By the downregulation of TIMP production and the concomitant upregulation of MMPs as a response to particle exposure, bone formation around implants may be suppressed, resulting in implant failure.

Adenoviral transduction supports matrix expression of alginate cultured articular chondrocytes

The present study examines the effects of adenoviral (Ad) transduction of human primary chondrocyte on transgene expression and matrix production. Primary chondrocytes were isolated from healthy articular cartilage and from cartilage with mild osteoarthritis (OA), transduced with an Ad vector and either immediately cultured in alginate or expanded in monolayer before alginate culture. Proteoglycan production was measured using dimethylmethylene blue (DMMB) assay and matrix gene expression was quantified by real-time PCR. Viral infection of primary chondrocytes results in a stable long time transgene expression for up to 13 weeks. Ad transduction does not significantly alter gene expression and matrix production if chondrocytes are immediately embedded in alginate. However, if expanded prior to three dimension (3D) culture in alginate, chondrocytes produce not only more proteoglycans compared to non-transduced controls, but also display an increased anabolic and decreased catabolic activity compared to non-transduced controls. We therefore suggest that successful autologous chondrocyte transplantation (ACT) should combine adenoviral transduction of primary chondrocytes with expansion in monolayer followed by 3D culture. Future studies will be needed to investigate whether the subsequent matrix production can be further improved by using Ad vectors bearing genes encoding matrix proteins.

Effect of betaTCP filled polyetheretherketone on osteoblast cell proliferation in vitro

Non-resorbable thermoplastic polymers have become more important for reconstructive surgery due to their excellent chemical and physical properties. Polyetheretherketone-beta-tricalcium phosphate (betaTCP-PEEK) composites were developed as alternative materials for load-bearing applications. This study presents the effect of polyetheretherketone (PEEK) specimens incorporated with 5, 10, 20 and 40 wt% beta-tricalcium phosphate (betaTCP) and processed by injection molding on cultivated osteoblast cells. Normal human osteoblast (NHOst) cells were seeded onto polymer discs to evaluate cell viability and proliferation after 24, 72 and 120 h of cultivation by employing the WST-1 assay. Standard tissue culture plastic was used as a control. The osteoblast cells were found to be viable in all PEEK groups, while the cell proliferation was progressively inhibited due to the incorporated beta-tricalcium phosphate. BetaTCP-PEEK showed concentration independent decrease of cell proliferation compared to the unfilled PEEK and the control group. In summary, this study confirms the non-toxic nature of pure PEEK, whereas this could not definitely be verified for betaTCP-PEEK as a composite material in chosen concentrations of beta-tricalcium phosphate in vitro.

Effect of βTCP filled polyetheretherketone on osteoblast cell proliferation in vitro

Non-resorbable thermoplastic polymers have become more important for reconstructive surgery due to their excellent chemical and physical properties. Polyetheretherketone-beta-tricalcium phosphate (betaTCP-PEEK) composites were developed as alternative materials for load-bearing applications. This study presents the effect of polyetheretherketone (PEEK) specimens incorporated with 5, 10, 20 and 40 wt% beta-tricalcium phosphate (betaTCP) and processed by injection molding on cultivated osteoblast cells. Normal human osteoblast (NHOst) cells were seeded onto polymer discs to evaluate cell viability and proliferation after 24, 72 and 120 h of cultivation by employing the WST-1 assay. Standard tissue culture plastic was used as a control. The osteoblast cells were found to be viable in all PEEK groups, while the cell proliferation was progressively inhibited due to the incorporated beta-tricalcium phosphate. BetaTCP-PEEK showed concentration independent decrease of cell proliferation compared to the unfilled PEEK and the control group. In summary, this study confirms the non-toxic nature of pure PEEK, whereas this could not definitely be verified for betaTCP-PEEK as a composite material in chosen concentrations of beta-tricalcium phosphate in vitro.

[Hepatitis B virus infections in hospitals]

Subclinical and clinical cases of hepatitis B virus (HBV) infection in hospital personnel were recorded over a five-year period. Although our data indicate the existence of "high-risk areas" like laboratories, dialysis units or surgical wards, it was found that 50% of all HBV infections were observed outside these areas. During the same period, most of our inpatients were monitored for HBs-antigenemia. It could be demonstrated that more than 50% of all cases of HBs-antigenemia were not known before and were treated primarily for other reasons than for hepatitis B. As a consequence from our data and from the screening for environmental HBs-antigen on laboratory surfaces it may be concluded for the hospital routine: Even minimal contaminations with blood should be avoided, all personnel should be vaccinated against HBs-antigen, HBs-antigen should be determined in every inpatient to detect inapparent virus carriers.