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Expression of the C-type lectins DC-SIGN or L-SIGN alters host cell susceptibility for the avian coronavirus, infectious bronchitis virus

Department of Microbiology and Immunology, College of Veterinary Medicine, Cornell University, Ithaca, NY 14853, USA.
Veterinary Microbiology (Impact Factor: 2.73). 01/2012; 157(3-4):285-93. DOI: 10.1016/j.vetmic.2012.01.011
Source: PubMed

ABSTRACT Infectious bronchitis virus (IBV), an avian coronavirus, is a cause of great economic loss in the poultry industry. The virus mainly infects respiratory epithelium, but can be also detected in other organs. The functional receptor for the virus has not been found and field strains of IBV do not infect conventional cell lines. Recently, it has been shown that the C-type lectins DC-SIGN/L-SIGN can promote entry of several coronaviruses. Here we examine whether DC-SIGN/L-SIGN are entry determinants for IBV. We show that by introducing human DC-SIGN/L-SIGN into non-permissive cells, infection by the IBV is dramatically increased. DC-SIGN mediated infection was inhibited by mannan and anti-lectin antibodies, and was independent of sialic acid levels on the cell. Enhancement of IBV infection also occurred for different serotypes of IBV. Our findings demonstrated that even in the absence of avian-specific receptor, DC-SIGN-like lectins are capable of mediating efficient IBV infection.

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    • "According to various reports, DC-specific C type lectin DC-SIGN is an important attachment factor for dissemination of several pathogens. As viral attachment factors, DC-SIGN (R) can enhance the susceptibility of permissive cells to viral infection or allow non-permissive cells to bind and transmit captured pathogens to target cells in trans (Halary et al., 2002; Navarro-Sanchez et al., 2003; Borggren et al., 2012; Mesman et al., 2012; Zhang et al., 2012). These attachment factors have high affinity for the mannose containing carbohydrates on viral glycoproteins (Klimstra et al., 2003; Lin et al., 2003; Johnson et al 2011; Alen et al., 2012). "
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    • "For avian gammacoronaviruses, no such protein receptor has been elucidated, but alpha-2,3 linked sialic acids have been shown to be essential for attachment and subsequent infection of avian cells (Abd El Rahman et al., 2009; Wickramasinghe et al., 2011; Winter et al., 2006, 2008). In addition, it was recently demonstrated that expression of human DC-SIGNlike lectins renders cells susceptible to IBV infection (Zhang et al., 2012), but no avian counterpart of this molecule has yet been identified . Thus, the molecular determinants for the host and tissue range of IBV are yet far from understood. "
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