Type 2 rhinovirus infection of cultured human tracheal epithelial cells: role of LDL receptor

To examine the role of the low-density lipoprotein (LDL) receptor on minor group human rhinovirus (RV) infection, primary cultures of human tracheal e pithelial cells were infected with a minor group (RV2) or a major group (RV 14) RV. Viral infection was confirmed by showing with PCR that viral titers in supernatants and lysates from infected cells increased with time. RV2 a nd RV14 increased expression of mRNA and protein of the LDL receptor on the cells and the cytokine production. RV2 induced activation of transcription factors SP1 and nuclear factor-kappaB (NF-kappaB). An antibody to the LDL receptor inhibited RV2 infection and RV2-induced cytokine production withou t an effect on RV14 infection and RV14-induced cytokine production. These f indings imply that RV2 upregulates LDL receptor expression on airway epithe lial cells, thereby increasing susceptibility to minor group RV infection. LDL receptor expression and cytokine production may be mediated, in part, v ia activation of transcription factors by RV2. These events may be importan t in airway inflammation after minor group RV infection in asthma.