A view of recent highlights of rotavirus research
Ulrich Desselberger, M.D.Department of Medicine, University of Cambridge, Addenbrooke’s Hospital, Cambridge CB2 0QQ, U.K.
Ruth Bishop Lecture, 13th International Rotavirus Symposium, Minsk/Belarus, 29-31 August 2018
Discovery of rotavirus as cause of infantile acute gastroenteritis
“Almost all particles had a highly electron-dense core, 33 nm in diameter, surrounded by a moderately densecapsid zone, 67 nm in diameter, about 10 percent ofparticles appeared to be enveloped (88nm in diameter). …The particles bear a marked resemblance to EDIM virus,the etiologic agent of epizootic diarrhea of infant mice.”
Electron microscopy of fecal suspensions: “In some of the specimens particles were discovered closely resembling reoviruses…”
Flewett TH, Bryden AS, Davies H.Virus particles in gastroenteritis. Lancet 1973 Dec 29; 2(7843): 1497.
Bishop RF, Davidson GP, Holmes IH, Ruck BJ. Evidence for viral gastroenteritis. N Engl J Med 1973 Nov 15; 289(20); 1096-1097.Lancet 1973 Dec 9; 2(7842): 1281-1283.
From: McClain B et al, J Mol Biol 2010; 397; 587-599.Settembre EC et al, EMBO J 2011; 30: 408-416.
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Rotavirus particle structure
Rotavirus structure-functions: VP1 = RdRp
From: - Lu X et al, Structure 2008; 16: 1678-1688. - Harrison S, Dormitzer P, Viral Gastroenteritis, pp 89-102, Elsevier, Amsterdam.
A B C
From: Sastri NP et al, Viral Gastroenteritis, pp 145-174. Elsevier, Amsterdam, 2016
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Intracellular NSP4 Extracellular NSP4
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NSP4: structure and functions
Structure of dsRNA in particles of the Cypovirus genus of the Reoviridae
From: Liu HR, Cheng LP, Science 2015; 349: 1347-1350. Zhang X et al, Nature 2015; 527: 531-534.
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Rotavirus viroplasms: interaction with lipid droplets
From: Cheung W et al, J Virol 2010; 84: 6782-6798.
From: Crawford SE, Desselberger U, Curr Opin Virol 2016;19:11-15.
Inhibitory effects on rotavirus replication of different compounds affecting lipid droplet homeostasis
Compound Treatment Viral RNA Infectivity of
of cells replication rotavirus progeny
[rel. values*] Diff log TCID50/ml** Diff
Isoproterenol - 1.00* 8.2
+ IBMX1 + 0.25 4-fold*** 6.5 50-fold
Triacsin C1 - 1.00 7.5
+ 0.26 3.8-fold 6.2 20-fold
TOFA2 - 1.00 8.4
+ 0.17 6-fold 6.7 50-fold
* Calculated from densitometric values of RNA gels** SE values not shown *** Underlining indicates statistical significance
1 From: Cheung W et al, J Virol 2010; 84: 6782-6798.2 From: Gaunt E et al, J Gen Virol 2013; 94; 1310-1317.
Rotavirus genome assortment and packaging: possible molecular mechanism
From: Borodavka A et al, eLife 2017; 6: e27453.Borodavka A et al, Curr Opin Virol 2018; 33: 106-112.
1 2 3 4
Rotavirus pathogenesis: molecular mechanism of vomiting
From: Hagbom M et al, PLoS Pathogens 2011; 7: e1002115.Hagbom M and Svensson L, Viral Gastroenteritis, pp 189-218. Elsevier, Amsterdam, 2016.
NTS, nucleus of the tractus solitarii; AP, area postrema
Rotavirus reverse genetics, helper virus-dependent
From: Trask SD et al, Proc Natl Acad Sci USA 2010: 107: 18652-18657.
Also achieved with various procedures using helper virus:
Komoto S et al, Proc Natl Acad Sci USA 2006; 103: 4646-4651.
Troupin C et al, J Virol 2010; 84: 6711-6719.
Navarro A et al, J Virol 2013; 87: 6211-6220.
Rotavirus reverse genetics, plasmid only-based I
From: Kanai Y et al, Proc Natl Acad Sci USA 2017; 114: 2349-2354.
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C D
Rotavirus reverse genetics, plasmid only-based II
From: Komoto S et al, J Virol 2018; 92: e00588-18.
Rotavirus reverse genetics, plasmid only-based III
From: Philip AA et al (JT Patton), Recombinant rotavirus expressing the Unagi fluorescent protein. American Society for Virology, Annual Meeting, July 2018 (with permission of the authors)
A
B CM 1 2 3
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M, size marker1, mock2, rSA113, rSA11/NSP1-FUnaG
Cross-neutralization specificity and titers of human mAbs isolated from human small intestine
From: Nair N et al, Science Translat Med 2017; 9: eaam5434.
VP6-specific rotavirus vaccine candidate
From: Lappalainen et al, Arch Virol 2015; 160: 2075-2078. Heinimaeki et al, Antiviral Res 2018; 157: 1-8.
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Reduction in virus shedding**
VP6 triv IM 67%VP6 triv IN 66%VP6 triv IM+IN 83%
*Adult mouse model (infection, not disease)
*
* Trivalent: RV VP6 tubules + NoV GI.3 and GII.4 VLPs
Neonatal RV3-BB (G3P[6]) vaccine candidate
Trial group Number of Participants Vaccine efficacy P valueparticipants with severe RV AGE % (95% CI)
_________________________________________________________________________Placebo 504 28 (5.6%) - -
Neon. Vac. Gr. 498 7 (1.4%) 75 (44-91) <0.001Inf. Vac. Gr. 511 14 (2.7%) 51 ( 7-76) <0.03
Comb. Vac. Gr. 1009 21 (2.1%) 63 (34-80) <0.001_________________________________________________________________________
From: Bines JE et al, N Engl J Med 2018; 378: 719-730.Based on: Barnes et al, Vaccine 2002; 20: 2950-2956; and earlier reports.
Summary: Recent highlights of rotavirus (RV) research*
Topic Major research groups______________________________________________________________________________• RV structural proteins and functions Harrison, Prasad, others • RV non-structural proteins (NSP2, NSP4) Prasad, Estes, others• RV replication in enteroids Estes, others• RV viroplasms interaction with lipid droplets Desselberger, Lever, others• RV RNA assortment and packaging Borodavka, others• RV pathogenesis Svensson, others• RV reverse genetics helper virus-dependent Patton, Taniguchi, Garbarg-Chenon• RV reverse genetics plasmid only-based Kobayashi, Komoto, Patton, others• Human RV broadly cross-neutralizing Mabs Greenberg, others• Novel human RV vaccine candidates Vesikari, Blazevic, Bines, Greenberg, others_______________________________________________________________________________
* Apologies to the many authors whose original and important work was not included here, due to time limitations. UD