SARS-CoV-2 Neutralizing Antibody-Negative Human Serum

Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) is an enveloped positive-stranded RNA virus and the causative agent of COVID-19, a primarily respiratory illness characterized by fever, cough, and shortness of breath that can lead to life-threatening complications.^1,2,3,4,5 The SARS-CoV-2 genome encodes four structural proteins: surface glycoprotein, envelope, membrane, and nucleocapsid.^2,1 The surface glycoprotein, also known as the spike glycoprotein, is located on the outer envelope of the virion and binds to the carboxypeptidase angiotensin-converting enzyme 2 (ACE2), which acts as the functional receptor for SARS-CoV-2 and facilitates virus cell entry.¹ SARS-CoV-2 infection results in the production of neutralizing antibodies, which bind to the SARS-CoV-2 spike glycoprotein receptor binding domain and prevent further viral entry and infection, starting approximately 4-10 days after symptom onset.^6,7 Plasma levels of SARS-CoV-2 spike glycoprotein-specific IgG antibodies increase for at least four weeks following symptom onset.^6,8 SARS-CoV-2 plasma antibody levels begin to decrease 2-3 months post-infection in both symptomatic and asymptomatic individuals, disappearing completely in some asymptomatic individuals.⁹ This product contains human serum negative for SARS-CoV-2 neutralizing antibodies.

Human blood products should always be properly handled in accordance with safe handling procedures. Disposal should follow state and federal regulations and is the responsibility of the customer.

WARNING This product is not for human or veterinary use.

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2. Lu, R., Zhao, X., Li, J., et al. Genomic characterisation and epidemiology of 2019 novel coronavirus: Implications for virus origins and receptor binding. Lancet 395(10224), 565-574 (2020).

3. Meo, S.A., Alhowikan, A.M., Al-Khlaiwi, T., et al. Novel coronavirus 2019-nCoV: Prevalence, biological and clinical characteristics comparison with SARS-CoV and MERS-CoV. Eur. Rev. Med. Pharmacol. Sci. 24(4), 2012-2019 (2020).

4. Klok, F.A., Kruip, M.J.H.A., van der Meer, N.J.M., et al. Incidence of thrombotic complications in critically ill ICU patients with COVID-19. Thromb. Res. 191, 145-147 (2020).

5. Yang, F., Shi, S., Zhu, J., et al. Analysis of 92 deceased patients with COVID-19. J. Med. Virol. 92(11), 2511-2515 (2020).

6. Wang, A., Zhang, L., Sang, L., et al. Kinetics of viral load and antibody response in relation to COVID-19 severity. J. Clin. Invest. 130(10), 5235-5244 (2020).

7. Xiang, F., Wang, X., He, X., et al. Antibody detection and dynamic characteristics in patients with coronavirus disease 2019. Clin. Infect. Dis. 71(8), 1930-1934 (2020).

8. Li, L., Tong, X., Chen, H., et al. Characteristics and serological patterns of COVID-19 convalescent plasma donors: Optimal donors and timing of donation. Transfusion 60(8), 1765-1772 (2020).

9. Long, Q.-X., Tang, X.-J., Shi, Q.-L., et al. Clinical and immunological assessment of asymptomatic SARS-CoV-2 infections. Nat. Med. 26(8), 1200-1204 (2020).