Hepatitis A virus cellular receptor 1 (HAVcr-1) is a member of the TIM (T cell transmembrane, immunoglobulin, and mucin) gene family, which plays critical roles in regulating immune cell activity especially regarding the host response to viral infection. TIM-1 is also involved in allergic response, asthma, and transplant tolerance. TIM genes belong to type I cell-surface glycoproteins, which include an N-terminal immunoglobulin (Ig)-like domain, a mucin domain with distinct length, a single transmembrane domain, and a C-terminal short cytoplasmic tail. TIM-1 is preferentially expressed on Th2 cells and has been identified as a stimulatory molecule for T-cell activation. As receptors for phosphatidylserine, TIM proteins bind many families of viruses [filovirus, flavivirus, New World arenavirus and alphavirus] that include viruses such as dengue and ebola. Entry of Lassa fever virus, influenza A virus, and SARS coronavirus were not affected by TIM-1 expression.