Membrane permeabilization by trypanosome lytic factor, a cytolytic human high density lipoprotein.

ABSTRACT: Trypanosome lytic factor (TLF) is a subclass of human high density lipoprotein (HDL) that mediates an innate immune killing of certain mammalian trypanosomes, most notably Trypanosoma brucei brucei, the causative agent of a wasting disease in cattle. Mechanistically, killing is initiated in the lysosome of the target trypanosome where the acidic pH facilitates a membrane-disrupting activity by TLF. Here we utilize a model liposome system to characterize the membrane binding and permeabilizing activity of TLF and its protein constituents, haptoglobin-related protein (Hpr), apolipoprotein L-1 (apoL-1), and apolipoprotein A-1 (apoA-1). We show that TLF efficiently binds and permeabilizes unilamellar liposomes at lysosomal pH, whereas non-lytic human HDL exhibits inefficient permeabilizing act

SUBMITTER: Harrington JM 

PROVIDER: S-EPMC2679451 | biostudies-literature | 2009 May

REPOSITORIES: biostudies-literature