Tulane virus recognizes sialic acids as cellular receptors

Area of Science:

• Virology
• Carbohydrate Chemistry
• Cell Biology

Background:

• Human noroviruses (huNoVs) infection studies are limited by the lack of effective cell culture models.
• Recent findings indicate huNoVs recognize sialic acids (SAs) and histo-blood group antigens (HBGAs).

Purpose of the Study:

• To investigate if Tulane virus (TV), a cultivable primate calicivirus, also interacts with SAs.
• To explore TV as a surrogate model for studying huNoV-host interactions involving multiple receptors.

Main Methods:

• Assessing TV virion binding to synthetic sialoglycoconjugates (SGCs).
• Evaluating the effect of neuraminidases and SA-binding lectins on TV infectivity in LLC-MK2 cells.
• Investigating the interaction of Maackia amurensis leukoagglutinin (MAL) with TV and LLC-MK2 cells.

Main Results:

• TV virions demonstrated binding to SGCs, indicating SA recognition.
• Enzymatic or lectin-based removal of SAs significantly inhibited TV infectivity.
• MAL, an α-2,3 linked SA-binding lectin, bound TV and LLC-MK2 cells, enhancing TV infectivity.

Conclusions:

• Tulane virus recognizes sialic acids, expanding the known host interactions for this calicivirus.
• TV serves as a valuable model for studying complex virus-host interactions, including those involving dual carbohydrate receptors like SAs and HBGAs.
• These findings offer new avenues for understanding calicivirus pathogenesis and developing antiviral strategies.