A key event in Leishmania pathogenesis is the interaction between parasite surface molecules and host immune cells. Among these, lipophosphoglycan (LPG), the dominant surface glycoconjugate of Leishmania promastigotes, plays a central role in establishing infection and evading immune responses. Beyond mediating adhesion and protection, LPG actively modulates host membrane receptors and intracellular signaling pathways. This chapter explores the multifaceted strategies by which LPG alters host...

Leishmania development in sand flies involves critical attachment steps to the midgut epithelium and the stomodeal valve, mediated by #parasite- and #vector-derived molecules. Initial midgut attachment prevents #parasite loss during defecation and determines #vector competence. In specific #vectors like Phlebotomus papatasi, attachment involves galectins and Leishmania lipophosphoglycan, while in permissive species like Lutzomyia longipalpis, mucin adhesion dominates. Later, promastigotes adhere to the stomodeal valve, forming adhesion plaques, which in combination with the promastigote secretory gel (PSG) blocks the gut and promotes transmission. Recent studies identified three flagellar proteins (KIAP1–3) crucial for plaque formation. Knockouts of KIAPs prevented stomodeal valve colonization and PSG production, likely impacting #parasite transmission. Thus, KIAPs are essential for late-stage Leishmania development in sand flies.

Leishmania development in sand flies involves critical attachment steps to the midgut epithelium and the stomodeal valve, mediated by #parasite- and #vector-derived molecules. Initial midgut attachment prevents #parasite loss during defecation and determines #vector competence. In specific #vectors like Phlebotomus papatasi, attachment involves galectins and Leishmania lipophosphoglycan, while in permissive species like Lutzomyia longipalpis, mucin adhesion dominates. Later, promastigotes adhere to the stomodeal valve, forming adhesion plaques, which in combination with the promastigote secretory gel (PSG) blocks the gut and promotes transmission. Recent studies identified three flagellar proteins (KIAP1–3) crucial for plaque formation. Knockouts of KIAPs prevented stomodeal valve colonization and PSG production, likely impacting #parasite transmission. Thus, KIAPs are essential for late-stage Leishmania development in sand flies.