A greater vaccine dose may be necessary for upper respiratory tract protection than for lower respiratory tract protection.
Suboptimal vaccine dose levels resulted in NSs losing protection but not enhanced viral replication as compared to the sham controls.
Although additional mechanisms may possibly lead to worsened disease, suboptimal vaccination dose levels resulted in viral breakthroughs but did not result in increased viral replication or pathology in the lungs of vaccinated animals as compared to sham controls.
Low-dose Ad26.COV2.S protection against SARS-CoV-2 challenge in rhesus macaques
Author(s) name
He X, Chandrashekar A et al.
Journal
Cell
Impact factor
27.35
Citation count: 20
Date of Entry
2022 Apr 29
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NLM format
He X, Chandrashekar A, Zahn R, Wegmann F, Yu J, Mercado NB, McMahan K, Martinot AJ, Piedra-Mora C, Beecy S, Ducat S, Chamanza R, Huber SR, van Heerden M, van der Fits L, Borducchi EN, Lifton M, Liu J, Nampanya F, Patel S, Peter L, Tostanoski LH, Pessaint L, Van Ry A, Finneyfrock B, Velasco J, Teow E, Brown R, Cook A, Andersen H, Lewis MG, Schuitemaker H, Barouch DH. Low-dose Ad26.COV2.S protection against SARS-CoV-2 challenge in rhesus macaques. Cell. 2021 Jun 24;184(13):3467-3473.e11. PMID:34133941
Intranasal challenge with SARS-CoV-2 virus protected the immunised hamsters (either a single-dose or a prime/boost vaccination regimen).
Two doses of vaccine elicited more potent neutralising antibody response and reduced peak and total virus shedding by a greater level.
Low levels of detectable virus was observed in the nasal turbinate tissue while lungs were completely clear from virus.
After two doses, MF59-vaccinated hamsters showed an apparent reduction in viral load in the lungs and nasal turbinate tissues.
In an animal model, neutralised antibody level is correlated with reduced virus shedding.
Preclinical development of a molecular clampstabilised subunit vaccine for severe acute respiratory syndrome coronavirus 2
Author(s) name
Watterson D, Wijesundara DK et al.
Journal
Clin Transl Immunology
Impact factor
8.18
Citation count: 16
Date of Entry
2022 Apr 29
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NLM format
Watterson D, Wijesundara DK, Modhiran N, Mordant FL, Li Z, Avumegah MS, McMillan CL, Lackenby J, Guilfoyle K, van Amerongen G, Stittelaar K, Cheung ST, Bibby S, Daleris M, Hoger K, Gillard M, Radunz E, Jones ML, Hughes K, Hughes B, Goh J, Edwards D, Scoble J, Pearce L, Kowalczyk L, Phan T, La M, Lu L, Pham T, Zhou Q, Brockman DA, Morgan SJ, Lau C, Tran MH, Tapley P, Villalón-Letelier F, Barnes J, Young A, Jaberolansar N, Scott CA, Isaacs A, Amarilla AA, Khromykh AA, van den Brand JM, Reading PC, Ranasinghe C, Subbarao K, Munro TP, Young PR, Chappell KJ. Preclinical development of a molecular clampstabilised subunit vaccine for severe acute respiratory syndrome coronavirus 2. Clin Transl Immunology. 2021 Apr 5;10(4):e1269. PMID:33841880
In mice and nonhuman primates, intramuscular vaccination with ARCoV mRNA-LNP generated significant neutralising antibodies against SARS-CoV-2 as well as a Th1-biased cellular response. In mice, two doses of ARCoV immunisation provided full protection against a SARS-CoV-2 mouse-adapted strain.
Immunized mice were fully protected against SARS-CoV-2 infection with no detectable viral RNA in the lungs or trachea, whereas high levels of viral RNA was observed in the lungs and trachea of placebo-treated mice.
A single dosage of ARCoV immunisation resulted in an anamnestic antibody response, however two doses of ARCoV immunisation did not result in an increase in neutralising antibody titers upon challenge, suggesting that sterilising immunity was produced in mice.
Zhang NN, Li XF, Deng YQ, Zhao H, Huang YJ, Yang G, Huang WJ, Gao P, Zhou C, Zhang RR, Guo Y, Sun SH, Fan H, Zu SL, Chen Q, He Q, Cao TS, Huang XY, Qiu HY, Nie JH, Jiang Y, Yan HY, Ye Q, Zhong X, Xue XL, Zha ZY, Zhou D, Yang X, Wang YC, Ying B, Qin CF. A Thermostable mRNA Vaccine against COVID-19. Cell. 2020 Sep 3;182(5):1271-1283.e16. PMID:32795413
Rhesus macaques were immunised with the BBIBP-CorV vaccine at low dose (2ug/dose) and high dose (8ug/dose). exposure to SARS-CoV-2 virus protected the immunised rhesus macaques.
Development of an Inactivated Vaccine Candidate, BBIBP-CorV, with Potent Protection against SARS-CoV-2
Author(s) name
Wang H, Zhang Y et al.
Journal
Cell
Impact factor
27.35
Citation count: 296
Date of Entry
2021 Oct 31
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NLM format
Wang H, Zhang Y, Huang B, Deng W, Quan Y, Wang W, Xu W, Zhao Y, Li N, Zhang J, Liang H, Bao L, Xu Y, Ding L, Zhou W, Gao H, Liu J, Niu P, Zhao L, Zhen W, Fu H, Yu S, Zhang Z, Xu G, Li C, Lou Z, Xu M, Qin C, Wu G, Gao GF, Tan W, Yang X. Development of an Inactivated Vaccine Candidate, BBIBP-CorV, with Potent Protection against SARS-CoV-2. Cell. 2020 Aug 6;182(3):713-721.e9. PMID:32778225