ABSTRACTTo initiate an antileishmanial adaptive immune response, dendritic cells (DCs) must carryLeishmaniaantigens from peripheral tissues to local draining lymph nodes. However, the migratory capacity of DCs is largely compromised duringLeishmania donovaniinfection. The molecular mechanism underlying this defective DC migration is not yet fully understood. Here, we demonstrate thatL. donovaniinfection impaired the lymph node homing ability of DCs by decreasing C-type lectin receptor 2 (CLEC-2) expression.L. donovaniexerted this inhibitory effect by inducing transforming growth factor-β (TGF-β) secretion from DCs. Indeed, TGF-β produced in this manner inhibited nuclear factor-κB (NF-κB)-mediated CLEC-2 expression on DCs by activating c-Src. Notably, suppression of c-Src expression significantly improved the arrival of DCs in draining lymph nodes by preventingL. donovani-induced CLEC-2 downregulation on DCs. These findings reveal a unique mechanism by whichL. donovaniinhibits DC migration to lymph nodes and suggest a key role for TGF-β, c-Src, and CLEC-2 in regulating this process.IMPORTANCEDendritic cells (DCs) play a key role in initiating T cell-mediated protective immunity against visceral leishmaniasis (VL), the second most lethal parasitic disease in the world. However, the T cell-inducing ability of DCs critically depends on the extent of DC migration to regional lymph nodes. Notably, the migration of DCs is reported to be impaired during VL. The cause of this impaired DC migration, however, remains ill-defined. Here, we provide the first evidence thatL. donovani, the causative agent of VL, attenuates the lymph node homing capacity of DCs by decreasing C-type lectin receptor 2 (CLEC-2) expression on DCs. Additionally, we have demonstrated howL. donovanimediates this inhibitory effect. Overall, our work has revealed a unique mechanism underlyingL. donovani-induced impairment of DC migration and suggests a potential strategy to improve antileishmanial T cell activity by increasing DC arrival in lymph nodes.