Identification of Mycobacterium tuberculosis clinical isolates with altered phagocytosis by human macrophages due to a truncated lipoarabinomannan.

ABSTRACT: Phenotypically distinct clinical isolates of Mycobacterium tuberculosis are capable of altering the balance that exists between the pathogen and human host and ultimately the outcome of infection. This study has identified two M. tuberculosis strains (i.e. HN885 and HN1554) among a bank of clinical isolates with a striking defect in phagocytosis by primary human macrophages when compared with strain Erdman, a commonly used laboratory strain for studies of pathogenesis. Mass spectrometry in conjunction with NMR studies unequivocally confirmed that both HN885 and HN1554 contain truncated and more branched forms of mannose-capped lipoarabinomannan (ManLAM) with a marked reduction of their linear arabinan (corresponding mainly to the inner Araf-alpha(1-->5)-Araf unit) and mannan (with fewer 6-

SUBMITTER: Torrelles JB 

PROVIDER: S-EPMC2581576 | biostudies-literature | 2008 Nov

REPOSITORIES: biostudies-literature