Biology subjects

Zandi, K.

Publications and source records attributed to Zandi, K..

4 recordsLinked to original sources

bioRxiv2024

Stably-Inverted Apical-Out Human Upper Airway Organoids for SARS-CoV-2 Infection and Therapeutic Testing

While breakthroughs with organoids have emerged as next-generation in vitro tools, standardization for drug discovery remains a challenge. This work introduces human airway organoids with reversed biopolarity (AORBs), cultured and analyzed in a high-throughput, single-organoid-per-well format, enabling milestones towards standardization. AORBs exhibit a spatio-temporally stable apical-out morphology, facilitating high-yield direct intact-organoid virus infection. Single-cell RNA sequencing and immunohistochemistry confirm the physiologically relevant recapitulation of differentiated human airway epithelia. The cellular tropism of five severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) strains along with host response differences between Delta, Washington, and Omicron variants, as observed in transcriptomic profiles, also suggest clinical relevance. Dose-response analysis of three well-studied SARS-CoV-2 antiviral compounds (remdesivir, bemnifosbuvir, and nirmatrelvir) demonstrates that AORBs efficiently predict human efficacy, comparable to gold-standard air-liquid interface cultures, but with higher throughput ([~]10-fold) and fewer cells ([~]100-fold). This combination of throughput and relevance allows AORBs to robustly detect false negative results in efficacy, preventing irretrievable loss of promising lead compounds. While this work leverages the SARS-CoV-2 study as a proof-of-concept application, the standardization capacity of AORB holds broader implications in line with regulatory efforts to push alternatives to animal studies.

bioengineering↗

bioRxiv2021

Inactivation of SARS Coronavirus 2 and COVID-19 patient samples for contemporary immunology and metabolomics studies

In late 2019, severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) emerged from Wuhan, China spurring the Coronavirus Disease-19 (COVID-19) pandemic that has resulted in over 219 million confirmed cases and nearly 4.6 million deaths worldwide. Intensive research efforts ensued to constrain SARS-CoV-2 and reduce COVID-19 disease burden. Due to the severity of this disease, the US Centers for Disease Control and Prevention (CDC) and World Health Organization (WHO) recommend that manipulation of active viral cultures of SARS-CoV-2 and respiratory secretions from COVID-19 patients be performed in biosafety level 3 (BSL3) containment laboratories. Therefore, it is imperative to develop viral inactivation procedures that permit samples to be transferred and manipulated at lower containment levels (i.e., BSL2), and maintain the fidelity of downstream assays to expedite the development of medical countermeasures (MCMs). We demonstrate optimal conditions for complete viral inactivation following fixation of infected cells with paraformaldehyde solution or other commonly-used branded reagents for flow cytometry, UVC inactivation in sera and respiratory secretions for protein and antibody detection assays, heat inactivation following cDNA amplification of single-cell emulsions for droplet-based single-cell mRNA sequencing applications, and extraction with an organic solvent for metabolomic studies. Thus, we provide a suite of protocols for viral inactivation of SARS-CoV-2 and COVID-19 patient samples for downstream contemporary immunology assays that facilitate sample transfer to BSL2, providing a conceptual framework for rapid initiation of high-fidelity research as the COVID-19 pandemic continues.

microbiology↗

bioRxiv2020

GNS561 exhibits potent in vitro antiviral activity against SARS-CoV-2 through autophagy inhibition

Since December 2019, severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2/2019-nCoV) has spread quickly worldwide, with more than 29 million cases and 920,000 deaths. Interestingly, coronaviruses were found to subvert and hijack the autophagic process to allow their viral replication. One of the spotlights had been focused on the autophagy inhibitors as a target mechanism effective in the inhibition of SARS-CoV-2 infection. Consequently, chloroquine (CQ) and hydroxychloroquine (HCQ), a derivative of CQ, was suggested as the first potentially be therapeutic strategies as they are known to be autophagy inhibitors. Then, they were used as therapeutics in SARS-CoV-2 infection along with remdesivir, for which the FDA approved emergency use authorization. Here, we investigated the antiviral activity and associated mechanism of GNS561, a small basic lipophilic molecule inhibitor of late-stage autophagy, against SARS-CoV-2. Our data indicated that GNS561 showed the highest antiviral effect for two SARS-CoV-2 strains compared to CQ and remdesivir. Focusing on the autophagy mechanism, we showed that GNS561, located in LAMP2-positive lysosomes, together with SARS-CoV-2, blocked autophagy by increasing the size of LC3-II spots and the accumulation of autophagic vacuoles in the cytoplasm with the presence of multilamellar bodies characteristic of a complexed autophagy. Finally, our study revealed that the combination of GNS561 and remdesivir was associated with a strong synergistic antiviral effect against SARS-CoV-2. Overall, our study highlights GNS561 as a powerful drug in SARS-CoV-2 infection and supports that the hypothesis that autophagy inhibitors could be an alternative strategy for SARS-CoV-2 infection.

pathology↗

bioRxiv2020

Baricitinib treatment resolves lower airway inflammation and neutrophil recruitment in SARS-CoV-2-infected rhesus macaques

Effective therapeutics aimed at mitigating COVID-19 symptoms are urgently needed. SARS-CoV-2 induced hypercytokinemia and systemic inflammation are associated with disease severity. Baricitinib, a clinically approved JAK1/2 inhibitor with potent anti-inflammatory properties is currently being investigated in COVID-19 human clinical trials. Recent reports suggest that baricitinib may also have antiviral activity in limiting viral endocytosis. Here, we investigated the immunologic and virologic efficacy of baricitinib in a rhesus macaque model of SARS-CoV-2 infection. Viral shedding measured from nasal and throat swabs, bronchoalveolar lavages and tissues was not reduced with baricitinib. Type I IFN antiviral responses and SARS-CoV-2 specific T cell responses remained similar between the two groups. Importantly, however, animals treated with baricitinib showed reduced immune activation, decreased infiltration of neutrophils into the lung, reduced NETosis activity, and more limited lung pathology. Moreover, baricitinib treated animals had a rapid and remarkably potent suppression of alveolar macrophage derived production of cytokines and chemokines responsible for inflammation and neutrophil recruitment. These data support a beneficial role for, and elucidate the immunological mechanisms underlying, the use of baricitinib as a frontline treatment for severe inflammation induced by SARS-CoV-2 infection.

immunology↗