LTF and infection: The innate response is pivotal in protecting the urogenital tract from infection.7 Previous studies have shown that incubating vaginal cells in vitro with low molecular weight (LMW) HA (< 200 kDa) elicits an innate immune response characterised by the synthesis of host defence (HD) molecules, including the defensins 1–3 and lactoferrin.31 In contrast, treatment of vaginal VK2 E6/E7 and bladder RT4 cells for 24 h with HMW HA did not affect the expression of either the DEFB4 or LCN2 genes, encoding the host defence agents BD2 and LCN2 (NGAL; Figure 2a and b).