SARS-CoV-2 RBD and Its Variants Can Induce Platelet Activation and Clearance: Implications for Antibody Therapy and Vaccinations against COVID-19

Xiaoying Ma; Jady Liang; Guangheng Zhu; Preeti Bhoria; Aron A Shoara; Daniel T MacKeigan; Christopher J Khoury; Sladjana Slavkovic; Lisha Lin; Danielle Karakas; Ziyan Chen; Viktor Prifti; Zhenze Liu; Chuanbin Shen; Yuchong Li; Cheng Zhang; Jiayu Dou; Zack Rousseau; Jiamin Zhang; Tiffany Ni; Xi Lei; Pingguo Chen; Xiaoyu Wu; Hamed Shaykhalishahi; Samira Mubareka; Kim A Connelly; Haibo Zhang; Ori Rotstein; Heyu Ni

doi:10.34133/research.0124

SARS-CoV-2 RBD and Its Variants Can Induce Platelet Activation and Clearance: Implications for Antibody Therapy and Vaccinations against COVID-19

Research (Wash D C). 2023 Apr 24:6:0124. doi: 10.34133/research.0124. eCollection 2023.

Authors

Xiaoying Ma^{1

2

3}, Jady Liang^{2

4}, Guangheng Zhu^{2

3

5}, Preeti Bhoria^{1

2

3

5}, Aron A Shoara^{2

3

4}, Daniel T MacKeigan^{2

3

4}, Christopher J Khoury^{1

2

3}, Sladjana Slavkovic^{1

2

5

6}, Lisha Lin^{2

3}, Danielle Karakas^{1

2

3}, Ziyan Chen^{1

2

3

6}, Viktor Prifti^{1

2

3}, Zhenze Liu^{1

2

3}, Chuanbin Shen^{1

2

3}, Yuchong Li^{2

7}, Cheng Zhang^{5

8}, Jiayu Dou^{2

3}, Zack Rousseau^{1

2

3}, Jiamin Zhang^{1

2

3}, Tiffany Ni^{1

2

3}, Xi Lei^{2

3

5}, Pingguo Chen^{1

2

3

6}, Xiaoyu Wu⁹, Hamed Shaykhalishahi^{2

3

5}, Samira Mubareka^{1

10}, Kim A Connelly^{2

11

12}, Haibo Zhang^{2

7

10

13

14}, Ori Rotstein^{2

15}, Heyu Ni^{1

2

3

4

5

6

11}

Affiliations

¹ Department of Laboratory Medicine and Pathobiology, University of Toronto, Toronto, ON, Canada.
² Department of Laboratory Medicine, Keenan Research Centre for Biomedical Science of St. Michael's Hospital, Toronto, ON, Canada.
³ Toronto Platelet Immunobiology Group, Toronto, ON, Canada.
⁴ Department of Physiology, University of Toronto, Toronto, ON, Canada.
⁵ CCOA Therapeutics Inc., Toronto, ON, Canada.
⁶ Canadian Blood Services Centre for Innovation, Toronto, ON, Canada.
⁷ The State Key Laboratory of Respiratory Disease, Guangzhou Institute of Respiratory Disease, The First Affiliated Hospital of Guangzhou Medical University, Guangzhou, Guangdong, China.
⁸ Department of Laboratory Medicine, The Second Affiliated Hospital of Guangzhou University of Chinese Medicine, Guangzhou, China.
⁹ Advanced Pharmaceutics & Drug Delivery Laboratory, Leslie Dan Faculty of Pharmacy, University of Toronto, Toronto, ON, Canada.
¹⁰ Department of Medical Microbiology and Infectious Disease, Sunnybrook Health Science Centre, Toronto, ON, Canada.
¹¹ Department of Medicine, University of Toronto, Toronto, ON, Canada.
¹² Division of Cardiology, St. Michael's Hospital, Toronto, ON, Canada.
¹³ Department of Anesthesiology and Pain Medicine and Division of Critical Care Medicine, University of Toronto, Toronto, ON, Canada.
¹⁴ Interdepartmental Division of Critical Care Medicine, University of Toronto, Toronto, ON, Canada.
¹⁵ Department of Surgery, University of Toronto, Toronto, ON, Canada.

Abstract

The COVID-19 pandemic caused by SARS-CoV-2 virus is an ongoing global health burden. Severe cases of COVID-19 and the rare cases of COVID-19 vaccine-induced-thrombotic-thrombocytopenia (VITT) are both associated with thrombosis and thrombocytopenia; however, the underlying mechanisms remain inadequately understood. Both infection and vaccination utilize the spike protein receptor-binding domain (RBD) of SARS-CoV-2. We found that intravenous injection of recombinant RBD caused significant platelet clearance in mice. Further investigation revealed the RBD could bind platelets, cause platelet activation, and potentiate platelet aggregation, which was exacerbated in the Delta and Kappa variants. The RBD-platelet interaction was partially dependent on the β3 integrin as binding was significantly reduced in β3^-/- mice. Furthermore, RBD binding to human and mouse platelets was significantly reduced with related αIIbβ3 antagonists and mutation of the RGD (arginine-glycine-aspartate) integrin binding motif to RGE (arginine-glycine-glutamate). We developed anti-RBD polyclonal and several monoclonal antibodies (mAbs) and identified 4F2 and 4H12 for their potent dual inhibition of RBD-induced platelet activation, aggregation, and clearance in vivo, and SARS-CoV-2 infection and replication in Vero E6 cells. Our data show that the RBD can bind platelets partially though αIIbβ3 and induce platelet activation and clearance, which may contribute to thrombosis and thrombocytopenia observed in COVID-19 and VITT. Our newly developed mAbs 4F2 and 4H12 have potential not only for diagnosis of SARS-CoV-2 virus antigen but also importantly for therapy against COVID-19.