Rotaviruses, of the family Reoviridae, are triple-layered particles (TLPs) ISRIB consisting
of the outer capsid, inner capsid and core. The rotavirus genome consists of 11 dsRNA segments which code for the six structural (VP1-VP4, VP6, VP7) and five non-structural (NSP1-NSP5) proteins. The outer capsid proteins, VP7 and VP4, serve as viral attachment proteins and neutralization antigens [3]. VP4 is activated by proteolytic cleavage into two fragments—VP8* and VP5*. VP8* forms a globular attachment domain at the tip of the VP5* stalk [4]. A binary system classifies group A rotaviruses into 27 G and 37 P types [5] and [6], a classification initially based on neutralization specificities of VP7 (Glycoprotein) and VP4 (Protease sensitive protein). Globally, G1P[8], G2P[4], G3P[8], G4P[8] and G9P[8] genotype combinations of rotavirus strains are the most common cause of human infections [7]. Of these, G1P[8] strains are most predominant (37.7%) [7]. These strains exhibit diversity in the form of 11 G1 and 4 P[8] subgenotypic lineages
[8] and [9]. According to a multi-centre hospital-based study carried out in India from 2005 to 2009, G1P[8] strains were highly prevalent [10]. Two rotavirus vaccines, Rotarix and RotaTeq, are currently licensed in Venetoclax mouse many countries including India. Rotarix is a monovalent vaccine containing the attenuated human G1P[8] rotavirus strain 89-12. RotaTeq is a pentavalent vaccine containing five human-bovine reassortant rotavirus strains, each representing one human genotype—WI79-9 (G1), SC2-9 (G2), WI78-9 (G3), MycoClean Mycoplasma Removal Kit BrB-9 (G4) and WI79-4 (P[8]). Studies from different countries have revealed that the G1 and P[8] subgenotypic lineages included in these vaccines, prevalent at the time of vaccine development (1980s), are not predominant today [8], [9], [11], [12], [13], [14], [15], [16], [17], [18], [19], [20], [21], [22] and [23]. Earlier, we have reported
identification of different lineages within VP7 gene of G1 rotaviruses circulating in Pune, western India [24]. The study did not include analysis of the corresponding P[8] lineages of VP4 genes and the rotavirus vaccine strains, 89-12 (Rotarix G1P[8]), WI79-9 (RotaTeq G1) and WI79-4 (RotaTeq P[8]) were not compared due to the unavailability of their sequence data at the time. The aim of the present study was to assess the diversity of G1P[8] rotavirus strains circulating among children with diarrhoea in Pune during the two time periods, 1992–1993 and 2006–2008, and compare sequences with the G1 and P[8] components of vaccines. A surveillance program for rotavirus disease and strains was carried out in children (<5 years), hospitalized for diarrhoea in Pune city during 1990s and 2000s [10] and [25] (Table 1). The G1P[8] rotavirus strains identified during the years 1992 (n = 8), 1993 (n = 11), 2006 (n = 21), 2007 (n = 29) and 2008 (n = 13) were selected in the present study for further characterization.