Journal: eBioMedicine

Article Title: A humanised ACE2, TMPRSS2, and FCGRT mouse model reveals the protective efficacy of anti-receptor binding domain antibodies elicited by SARS-CoV-2 hybrid immunity

doi: 10.1016/j.ebiom.2025.105619

Figure Lengend Snippet: hACE2-hTMPRSS2-hFCGRT TKI mice support SARS-CoV-2 Delta infection . (a, b) RT-PCR analysis of human (h) or mouse (m) ACE2, TMPRSS2, and FCGRT mRNA in tissues from (a) TKI and (b) C57BL/6J (B6) mice. Mouse glyceraldehyde 3-phosphate dehydrogenase (m Gapdh ) mRNA was probed as a loading control. (c) Western blot analysis of human or mouse proteins in the lung and nasal turbinate (nt) tissues from TKI and B6 mice. (d) Experimental protocol for the data shown in (e) . TKI mice were inoculated intranasally with SARS-CoV-2 Delta (50 × 10 3 PFU), and nt and lung tissues were harvested on days 2, 3, and 4 post-infection. (e) RT-qPCR analysis of Delta E genomic (g) and 7a subgenomic (sg) RNA, and plaque assay of infectious virus in the nt and/or lungs on days 2, 3, and 4 post-infection. (f) Experimental protocol for the data shown in (g) . TKI mice were inoculated intranasally with SARS-CoV-2 Delta (0.5, 5, or 50 × 10 3 PFU), and nt, lung, and brain tissues were harvested on day 2 post-infection. (g) RT-qPCR analysis of Delta 7a sgRNA and plaque assay of infectious virus in the nt, lung, and brain tissues on day 2 post-infection. Data are presented as the mean ± SEM of 5 mice/group in (e) and 7–8 mice/group in (g) . Circles represent individual mice and dotted lines indicate the limit of detection. Group means were compared by the Kruskal–Wallis test. ∗ P < 0.05, ∗∗ P < 0.01.

Article Snippet: DKI mice (hACE2 and hTMPRSS2) and TKI mice (hACE2, hTMPRSS2, and hFCGRT; generated as described below) were bred at Synbal (San Diego, CA) and LJI, and housed in a specific pathogen-free facility under controlled temperature, humidity, and light (12 h on/off).

Techniques: Infection, Reverse Transcription Polymerase Chain Reaction, Control, Western Blot, Quantitative RT-PCR, Plaque Assay, Virus

Journal: eBioMedicine

Article Title: A humanised ACE2, TMPRSS2, and FCGRT mouse model reveals the protective efficacy of anti-receptor binding domain antibodies elicited by SARS-CoV-2 hybrid immunity

doi: 10.1016/j.ebiom.2025.105619

Figure Lengend Snippet: Functionality of hFcRn in hACE2-TMPRSS2-FCGRT TKI mice . (a) Pharmacokinetics of 1C3-YTE mAb, 1C3-WT mAb, and polyclonal human IgG (pAb) in TKI and DKI mice. Groups of treatment-naïve mice were injected intraperitoneally with 1 mg/kg mAbs or pAbs and bled at 3, 24, 72, 168, 336, and 504 h post-dose. Each mouse was bled at a maximum of two time points. Data are presented as the mean ± SEM of 3–8 mice/group/time point, pooled from two independent experiments. Group means at day 21 were compared by mixed-effect analysis and Šídák's correction. The open and filled bars represent DKI and TKI, respectively. (b) Half-life of 1C3-YTE, 1C3-WT, and pAbs in TKI and DKI mice. Group means were compared by mixed-effect analysis and Šídák's correction. The open and filled bars represent DKI and TKI, respectively. (c) Experimental protocol for the data shown in (d and e). TKI and DKI mice were injected intraperitoneally (d) or intranasally (e) with 0.5 mg/kg of 1C3-YTE, 1C3-WT, or an anti-SARS-CoV-1 hIgG (negative control). One day later, mice were inoculated intranasally with Omicron BA.2 (10 4 PFU in 30 μl) and nasal turbinate (nt) and lungs were harvested on day 2 post-infection. (d) and (e) RT-qPCR analysis of Omicron BA.2 subgenomic (sg) RNA and plaque assay of infectious virus in the nt and/or lungs of TKI and DKI mice on day 2 post-infection. Data are presented as the mean ± SEM of 6–12 mice/group, pooled from two independent experiments. Circles represent individual mice and dotted lines indicate the limit of detection. Group means were compared by the Kruskal–Wallis and Dunn's multiple comparisons tests. ∗ P < 0.05, ∗∗ P < 0.01, ∗∗∗ P < 0.001.

Article Snippet: DKI mice (hACE2 and hTMPRSS2) and TKI mice (hACE2, hTMPRSS2, and hFCGRT; generated as described below) were bred at Synbal (San Diego, CA) and LJI, and housed in a specific pathogen-free facility under controlled temperature, humidity, and light (12 h on/off).

Techniques: Drug discovery, Injection, Negative Control, Infection, Quantitative RT-PCR, Plaque Assay, Virus

Journal: eBioMedicine

Article Title: A humanised ACE2, TMPRSS2, and FCGRT mouse model reveals the protective efficacy of anti-receptor binding domain antibodies elicited by SARS-CoV-2 hybrid immunity

doi: 10.1016/j.ebiom.2025.105619

Figure Lengend Snippet: Differential efficacy of human plasma Abs elicited by SARS-CoV-2 vaccination or vaccination plus infection in protecting TKI mice against Delta infection . (a) Timelines of SARS-CoV-2 vaccination and infection for plasma donors. Plasma samples were collected on the indicated days from the three donor groups: 2-dose + inf Delta (n = 7; two doses of BNT162b2 vaccine followed by infection with Delta); 3-dose (n = 10; three doses of BNT162b2 vaccine); and 3-dose + inf Omicron (n = 5; three doses of BNT162b2 vaccine followed by infection with Omicron BA.1 or BA.2). Values in green represent the median ± interquartile range (IQR) days between the 2nd or 3rd vaccination and symptom onset; values in red represent the median ± IQR days between natural exposure or vaccination and plasma collection. Infection windows for 2-dose + inf Delta and 3-dose + inf Omicron groups were deduced from known symptom onset dates. (b) Anti-Delta spike (S) protein IgG ELISA, anti-Delta receptor-binding domain (RBD) IgG ELISA, pVSV-S Delta neutralisation assay, or PRNT Delta of plasma collected from donors in the 2-dose + inf Delta group or the 3-dose group. Data are presented as the geometric mean ± error from one experiment. White and red circles represent individual and pooled samples, respectively. (c) Experimental protocol for the data shown in (d). TKI mice were injected intraperitoneally with 500 μl of pooled plasma from the 2-dose + inf Delta or 3-dose groups or from SARS-CoV-2-naïve and unvaccinated donors (control). One day later, mice were inoculated intranasally with Delta (10 3 PFU), and nasal turbinate (nt), lungs, and blood samples were harvested on day 2 post-infection. (d) RT-qPCR analysis of Delta subgenomic (sg) RNA and plaque assay of infectious virus in the nt and/or lung tissues of TKI mice on day 2 post-infection. Circles represent individual mice and dotted lines indicate the limit of detection. Data are presented as the mean ± SEM of 8–10 mice/group, pooled from two independent experiments. Group means were compared by the Mann–Whitney test (b) or the unpaired Kruskal–Wallis and Dunn's multiple comparison tests (d). ∗ P < 0.05, ∗∗ P < 0.01.

Article Snippet: DKI mice (hACE2 and hTMPRSS2) and TKI mice (hACE2, hTMPRSS2, and hFCGRT; generated as described below) were bred at Synbal (San Diego, CA) and LJI, and housed in a specific pathogen-free facility under controlled temperature, humidity, and light (12 h on/off).

Techniques: Clinical Proteomics, Infection, Enzyme-linked Immunosorbent Assay, Binding Assay, Injection, Control, Quantitative RT-PCR, Plaque Assay, Virus, MANN-WHITNEY, Comparison

Journal: eBioMedicine

Article Title: A humanised ACE2, TMPRSS2, and FCGRT mouse model reveals the protective efficacy of anti-receptor binding domain antibodies elicited by SARS-CoV-2 hybrid immunity

doi: 10.1016/j.ebiom.2025.105619

Figure Lengend Snippet: Differential efficacy of human plasma Abs elicited by SARS-CoV-2 vaccination and Delta or Omicron BA.1/2 infection in protecting TKI mice against Omicron BA.5 infection . (a) Anti-Omicron BA.5 spike (S) protein IgG ELISA, anti-Omicron BA.5 receptor-binding domain (RBD) IgG ELISA, pVSV-S BA.5 neutralisation assay, or PRNT BA.5 of plasma collected from donors in the 2-dose + inf Delta or 3-dose + inf Omicron groups indicated in Fig. 3 a. Data are presented as the geometric mean ± error from one experiment. White and red circles represent individual and pooled plasma samples, respectively. (b) Experimental protocol for the data shown in (c) . TKI mice were injected intraperitoneally with 500 μl of pooled plasma from the 2-dose + inf Delta or 3-dose groups or from SARS-CoV-2-naïve and unvaccinated donors (control). One day later, mice were inoculated intranasally with Omicron BA.5 (5 × 10 4 PFU), and nasal turbinate (nt) and lungs were harvested on day 2 post-infection. (c) RT-qPCR analysis of Omicron BA.5 subgenomic (sg) RNA and plaque assay of infectious virus in the nt and/or lung tissues of TKI mice on day 2 post-infection. Data are presented as the mean ± SD of 7–8 mice/group, pooled from two independent experiments. Circles represent individual mice and dotted lines indicate the limit of detection. Group means were compared by Kruskal–Wallis and Dunn's multiple comparison tests. ∗ P < 0.05.

Article Snippet: DKI mice (hACE2 and hTMPRSS2) and TKI mice (hACE2, hTMPRSS2, and hFCGRT; generated as described below) were bred at Synbal (San Diego, CA) and LJI, and housed in a specific pathogen-free facility under controlled temperature, humidity, and light (12 h on/off).

Techniques: Clinical Proteomics, Infection, Enzyme-linked Immunosorbent Assay, Binding Assay, Injection, Control, Quantitative RT-PCR, Plaque Assay, Virus, Comparison

Journal: eBioMedicine

Article Title: A humanised ACE2, TMPRSS2, and FCGRT mouse model reveals the protective efficacy of anti-receptor binding domain antibodies elicited by SARS-CoV-2 hybrid immunity

doi: 10.1016/j.ebiom.2025.105619

Figure Lengend Snippet: Human SARS-CoV-2 RBD-binding Abs from vaccinated and Omicron-infected donors protect TKI mice against Delta infection . (a) PRNT of 3-dose + inf Omicron plasma samples after depletion of RBD-binding Abs or mock-depletion. Data are presented as the mean of two duplicates. (b) Experimental protocol for the data shown in (c) . TKI mice were injected intraperitoneally with 500 μl of pooled plasma from SARS-CoV-2-naïve and unvaccinated donors (control) or 3-dose + inf Omicron plasma depleted of RBD-binding Abs or mock depleted. One day later, mice were inoculated intranasally with Delta (10 3 PFU), and nasal turbinate (nt) and lungs were harvested on day 2 post-infection. (c) RT-qPCR analysis of Delta subgenomic (sg) RNA and plaque assay of infectious virus in the nt and/or lung tissues of TKI mice on day 2 post-infection. Data are presented as the mean ± SD of 10–12 mice/group, pooled from two independent experiments. Circles represent individual mice and dotted lines indicate the limit of detection. Group means were compared by unpaired Kruskal–Wallis and Dunn's multiple comparison tests. ∗ P < 0.05, ∗∗∗ P < 0.001.

Article Snippet: DKI mice (hACE2 and hTMPRSS2) and TKI mice (hACE2, hTMPRSS2, and hFCGRT; generated as described below) were bred at Synbal (San Diego, CA) and LJI, and housed in a specific pathogen-free facility under controlled temperature, humidity, and light (12 h on/off).

Techniques: Binding Assay, Infection, Clinical Proteomics, Injection, Control, Quantitative RT-PCR, Plaque Assay, Virus, Comparison

Journal: eBioMedicine

Article Title: A humanised ACE2, TMPRSS2, and FCGRT mouse model reveals the protective efficacy of anti-receptor binding domain antibodies elicited by SARS-CoV-2 hybrid immunity

doi: 10.1016/j.ebiom.2025.105619

Figure Lengend Snippet: Functionality of hFcRn in hACE2-TMPRSS2-FCGRT TKI mice . (a) Pharmacokinetics of 1C3-YTE mAb, 1C3-WT mAb, and polyclonal human IgG (pAb) in TKI and DKI mice. Groups of treatment-naïve mice were injected intraperitoneally with 1 mg/kg mAbs or pAbs and bled at 3, 24, 72, 168, 336, and 504 h post-dose. Each mouse was bled at a maximum of two time points. Data are presented as the mean ± SEM of 3–8 mice/group/time point, pooled from two independent experiments. Group means at day 21 were compared by mixed-effect analysis and Šídák's correction. The open and filled bars represent DKI and TKI, respectively. (b) Half-life of 1C3-YTE, 1C3-WT, and pAbs in TKI and DKI mice. Group means were compared by mixed-effect analysis and Šídák's correction. The open and filled bars represent DKI and TKI, respectively. (c) Experimental protocol for the data shown in (d and e). TKI and DKI mice were injected intraperitoneally (d) or intranasally (e) with 0.5 mg/kg of 1C3-YTE, 1C3-WT, or an anti-SARS-CoV-1 hIgG (negative control). One day later, mice were inoculated intranasally with Omicron BA.2 (10 4 PFU in 30 μl) and nasal turbinate (nt) and lungs were harvested on day 2 post-infection. (d) and (e) RT-qPCR analysis of Omicron BA.2 subgenomic (sg) RNA and plaque assay of infectious virus in the nt and/or lungs of TKI and DKI mice on day 2 post-infection. Data are presented as the mean ± SEM of 6–12 mice/group, pooled from two independent experiments. Circles represent individual mice and dotted lines indicate the limit of detection. Group means were compared by the Kruskal–Wallis and Dunn's multiple comparisons tests. ∗ P < 0.05, ∗∗ P < 0.01, ∗∗∗ P < 0.001.

Article Snippet: DKI mice (hACE2 and hTMPRSS2) and TKI mice (hACE2, hTMPRSS2, and hFCGRT; generated as described below) were bred at Synbal (San Diego, CA) and LJI, and housed in a specific pathogen-free facility under controlled temperature, humidity, and light (12 h on/off).

Techniques: Drug discovery, Injection, Negative Control, Infection, Quantitative RT-PCR, Plaque Assay, Virus

Journal: eBioMedicine

Article Title: A humanised ACE2, TMPRSS2, and FCGRT mouse model reveals the protective efficacy of anti-receptor binding domain antibodies elicited by SARS-CoV-2 hybrid immunity

doi: 10.1016/j.ebiom.2025.105619

Figure Lengend Snippet: hACE2-hTMPRSS2-hFCGRT TKI mice support SARS-CoV-2 Delta infection . (a, b) RT-PCR analysis of human (h) or mouse (m) ACE2, TMPRSS2, and FCGRT mRNA in tissues from (a) TKI and (b) C57BL/6J (B6) mice. Mouse glyceraldehyde 3-phosphate dehydrogenase (m Gapdh ) mRNA was probed as a loading control. (c) Western blot analysis of human or mouse proteins in the lung and nasal turbinate (nt) tissues from TKI and B6 mice. (d) Experimental protocol for the data shown in (e) . TKI mice were inoculated intranasally with SARS-CoV-2 Delta (50 × 10 3 PFU), and nt and lung tissues were harvested on days 2, 3, and 4 post-infection. (e) RT-qPCR analysis of Delta E genomic (g) and 7a subgenomic (sg) RNA, and plaque assay of infectious virus in the nt and/or lungs on days 2, 3, and 4 post-infection. (f) Experimental protocol for the data shown in (g) . TKI mice were inoculated intranasally with SARS-CoV-2 Delta (0.5, 5, or 50 × 10 3 PFU), and nt, lung, and brain tissues were harvested on day 2 post-infection. (g) RT-qPCR analysis of Delta 7a sgRNA and plaque assay of infectious virus in the nt, lung, and brain tissues on day 2 post-infection. Data are presented as the mean ± SEM of 5 mice/group in (e) and 7–8 mice/group in (g) . Circles represent individual mice and dotted lines indicate the limit of detection. Group means were compared by the Kruskal–Wallis test. ∗ P < 0.05, ∗∗ P < 0.01.

Article Snippet: Membranes were blocked with AdvanBlock-Chemi solution (Advansta) for 1 h at room temperature, and incubated with the following primary Abs diluted in AdvanBlock-Chemi solution at 4 °C overnight: hACE2 (GeneTex, GTX15349), hTMPRSS2 (Santa Cruz Biotechnology, sc-515727), hFcRn (Santa Cruz Biotechnology, sc-271745), mGAPDH (Cell Signalling, 14C10), mACE2 (R&D Systems, AF3437), mTMPRSS2 (Santa Cruz Biotechnology, sc-515727), and mFcRn (R&D Systems, AF6776).

Techniques: Infection, Reverse Transcription Polymerase Chain Reaction, Control, Western Blot, Quantitative RT-PCR, Plaque Assay, Virus