Journal: PLOS Pathogens

Article Title: Update and reuse: Structure-guided nanobody evolution against SARS-CoV-2 escape

doi: 10.1371/journal.ppat.1014223

Figure Lengend Snippet: A bispecific nanobody, Nanosota-9A/9B-Fc, was generated by fusing Nanosota-9A and Nanosota-9B to a human Fc domain. (A) Efficacy of Nanosota-9A/9B-Fc in neutralizing Omicron pseudoviruses. The assay was performed as in . (B) Efficacy of Nanosota-9A/9B-Fc in neutralizing authentic Omicron in vitro. Each Omicron subvariant infected Vero E6-ACE2-TMPRSS2 cells in the presence of Nanosota-9A/9B-Fc at different concentrations. Infection efficiency was determined by the remaining cell viability after 96 hours (lower viability indicates higher infection). Efficacy for each subvariant is expressed as the IC₅₀, the concentration that reduces virus-induced cytopathic effect by 50% relative to serum-exposed virus controls. Data are mean ± SEM (n = 4). (C) Efficacy of Nanosota-9A/9B-Fc in neutralizing authentic Omicron (JN.1, KP.2, and KP.3) in mice. The experiment followed and , except lung virus titers on day 2 post-infection were measured by TCID₅₀ assay. Treatment groups, n = 5; control groups, n = 4. Comparisons of lung virus titers between the control and treatment groups were performed using an unpaired two-tailed Student’s t-test. **p < 0.01.

Article Snippet: HEK293T and Vero E6-ACE2-TMPRSS2 cells (Vero E6 cells overexpressing human ACE2 and human TMPRSS2) (ATCC) were cultured in Dulbecco’s modified Eagle medium (DMEM) supplemented with 10% fetal bovine serum.

Techniques: Generated, In Vitro, Infection, Concentration Assay, Virus, Control, Two Tailed Test

Journal: bioRxiv

Article Title: Functional Landscape of Motifs within the Sarbecovirus Spike Cytoplasmic Tail

doi: 10.64898/2026.05.06.723231

Figure Lengend Snippet: a. Cell surface expression of human ACE2 in Vero E6, Vero E6-ACE2-TMPRSS2, 293T-ACE2, and 293T-ACE2-TMPRSS2 cells. b. Cell surface expression of human TMPRSS2 in the same cell lines as in a. c. Titration of VSV pseudoviruses bearing FL and CT-truncated spike glycoproteins in Vero E6-ACE2-TMPRSS2 cells. Infectivity was assessed by measuring luciferase activity (relative light units, RLU). Data are presented as mean ± s.d. of triplicates. d. Titration of VSV pseudoviruses bearing FL and CT-truncated spike glycoproteins in 293T-ACE2 cells e. Titration of VSV pseudoviruses bearing FL and CT-truncated spike glycoproteins in 293T-ACE2-TMPRSS2 cells. f. Infectivity of VSV pseudoviruses bearing the indicated FL spike proteins in Vero E6, Vero E6-ACE2-TMPRSS2, 293T-ACE2, and 293T-ACE2-TMPRSS2 cells. Fold increases in infectivity in Vero E6-ACE2-TMPRSS2 versus Vero E6 and in 293T-ACE2-TMPRSS2 versus 293T-ACE2 cells are shown. Dashed lines indicate background signal in the absence of virus input. g. Infectivity of VSV pseudoviruses bearing FL and CT-truncated spike proteins in Vero E6, Vero E6-ACE2-TMPRSS2, 293T-ACE2, and 293T-ACE2-TMPRSS2 cells. Dashed lines indicate background signal in the absence of virus input.

Article Snippet: To test the effect of host protease inhibitors on pseudovirus entry, Vero E6-ACE2-TMPRSS2 cells (4×104 cells/well) were pre-incubated for 2 hours with serially diluted cathepsin L inhibitor E64d (MedChemExpress, CAS# 88321-09-9) or TMPRSS2 inhibitor camostat mesylate (MedChemExpress, CAS# 59721-29-8).

Techniques: Expressing, Titration, Infection, Luciferase, Activity Assay, Virus

Journal: bioRxiv

Article Title: Functional Landscape of Motifs within the Sarbecovirus Spike Cytoplasmic Tail

doi: 10.64898/2026.05.06.723231

Figure Lengend Snippet: a. Infectivity of lentivirus pseudotyped with FL or CT-truncated SARS-CoV-1 spike in Vero E6 cells. b. Infectivity of lentivirus pseudotyped with FL or CT-truncated SARS-CoV-2 D614G spike in Vero E6 cells. c. Infectivity of lentivirus pseudotyped with FL or CT-truncated spikes in 293T-ACE2 cells. d. Infectivity of lentivirus pseudotyped with FL or CT-truncated indicated spikes in 293T-ACE2-TMPRSS2 cells.

Article Snippet: To test the effect of host protease inhibitors on pseudovirus entry, Vero E6-ACE2-TMPRSS2 cells (4×104 cells/well) were pre-incubated for 2 hours with serially diluted cathepsin L inhibitor E64d (MedChemExpress, CAS# 88321-09-9) or TMPRSS2 inhibitor camostat mesylate (MedChemExpress, CAS# 59721-29-8).

Techniques: Infection

Journal: bioRxiv

Article Title: Functional Landscape of Motifs within the Sarbecovirus Spike Cytoplasmic Tail

doi: 10.64898/2026.05.06.723231

Figure Lengend Snippet: a. Construction scheme of Δ5, Δ11, Δ13, Δ17, and ΔFBM. ΔFBM, deletion of FERM-binding motif. Solid black lines indicate COPI-, COPII-, and FERM-binding motifs. b. Titration of VSV pseudoviruses carrying FL or truncated spike proteins (Δ5, Δ13, and Δ17) of SARS-CoV-1 and SARS-CoV-2 D614G in Vero E6 cells. c. Fold changes in pseudovirus infectivity of VSV pseudotyped with Δ5, Δ13, and Δ17 spikes compared with that of the FL spike in panel b . Fold changes were derived from the linear range of infectivity values. Increased infectivity is shown in green and decreased infectivity in red. d. Titration of VSV pseudoviruses carrying FL or truncated spikes (ΔFBM, Δ13, and Δ17) of the indicated viruses in Vero-E6 and Vero E6-ACE2-TMPRSS2 cells. e. Fold changes in pseudovirus infectivity of VSV pseudotyped with ΔFBM, Δ13, and Δ17 spike compared with that of the FL spike in panel d . Fold changes were derived from the linear range of infectivity values. f. Co-immunoprecipitation assays assessing the interaction between moesin and FL or truncated D614G spike proteins. 293T cells were transfected with the indicated plasmids, and cell lysates were subjected to immunoprecipitation using an anti-spike monoclonal antibody (SA55). Protein expression and immunoprecipitation were detected by western blot using an anti-sarbecovirus spike monoclonal antibody (S2P6) and an anti-Strep tag antibody, respectively. Band intensities were quantified using ImageJ software, with both numerical values and color coding representing relative grayscale intensity.

Article Snippet: To test the effect of host protease inhibitors on pseudovirus entry, Vero E6-ACE2-TMPRSS2 cells (4×104 cells/well) were pre-incubated for 2 hours with serially diluted cathepsin L inhibitor E64d (MedChemExpress, CAS# 88321-09-9) or TMPRSS2 inhibitor camostat mesylate (MedChemExpress, CAS# 59721-29-8).

Techniques: Binding Assay, Titration, Infection, Derivative Assay, Immunoprecipitation, Transfection, Expressing, Western Blot, Strep-tag, Software

Journal: bioRxiv

Article Title: Functional Landscape of Motifs within the Sarbecovirus Spike Cytoplasmic Tail

doi: 10.64898/2026.05.06.723231

Figure Lengend Snippet: Neutralization curves of VSV pseudoviruses carrying FL, Δ13, and Δ17 spike to the indicated monoclonal neutralizing antibodies ( a ), serum samples collected after SARS-CoV-2 pandemic ( b ), hACE2 ( c ), and the protease inhibitors E64d and camostat ( d ). Antibody and serum neutralization assays, as well as hACE2 inhibition assays, were performed in Vero E6 cells, whereas protease inhibitor assays were conducted in Vero E6-ACE2-TMPRSS2 cells. Numbers in each panel denote IC 50 or ID 50 of pseudoviruses carrying FL (black), Δ13 (red), and Δ17 (blue) spikes.

Article Snippet: To test the effect of host protease inhibitors on pseudovirus entry, Vero E6-ACE2-TMPRSS2 cells (4×104 cells/well) were pre-incubated for 2 hours with serially diluted cathepsin L inhibitor E64d (MedChemExpress, CAS# 88321-09-9) or TMPRSS2 inhibitor camostat mesylate (MedChemExpress, CAS# 59721-29-8).

Techniques: Neutralization, Inhibition, Protease Inhibitor

Journal: PLOS Pathogens

Article Title: Collectin-11, a complement pattern recognition molecule, mediates pulmonary SARS-CoV-2 neutralization and protection

doi: 10.1371/journal.ppat.1014216

Figure Lengend Snippet: (A-C) Neutralization of infectious SARS-CoV-2 following incubation with two-fold dilutions of rCL-11 (black) in A549-hACE-2 cells (starting at 40 µg/ml) (A) , Calu-3 cells (starting at 20 µg/ml) (B) , and Huh7.5 cells (starting at 20 µg/ml) (C) using the conventional experimental setup. The mAb clone 61 was used as a neutralization control (orange) and rCL-11 buffer (gray) in corresponding dilutions was used to monitor buffer-mediated effects on the cells. The percentage of protected cells was determined from the number of SARS-CoV-2 infected cells in experimental wells compared to the number of infected cells in virus-only control wells after anti-S protein immunostaining. Data are shown as means ± SD of four (A549-hACE-2 and Calu-3 cells) or six (Huh7.5 cells) replicates.

Article Snippet: The human lung adenocarcinoma A549-hACE-2 cell line (InvivoGen, San Diego, California, USA) (A549 cells expressing human ACE-2) was maintained as described previously [ ].

Techniques: Neutralization, Incubation, Control, Infection, Virus, Immunostaining