Increased viability but decreased culturability of Mycobacterium avium subsp paratuberculosis in macrophages from inflammatory bowel disease patients under Infliximab treatment

• Type: Article in International Scientific Journal
• Date: 2015

Authors

Appelberg, R (Author) ICBAS

Journal

Title: Medical Microbiology and Immunology

Vol. 204

Pages: 647-656

ISSN: 0300-8584

Publisher: Springer Nature

Indexing

ISI Web of Knowledge - 8 Citations

Scopus - 0 Citations

Other information

Authenticus ID: P-00G-1XV

DOI: 10.1007/s00430-015-0393-2

Abstract (EN): Mycobacterium avium subsp. paratuberculosis (MAP) has long been implicated as a triggering agent in Crohn's disease (CD). In this study, we investigated the growth/persistence of both M. avium subsp. hominissuis (MAH) and MAP, in macrophages from healthy controls (HC), CD and ulcerative colitis patients. For viability assessment, both CFU counts and a pre16SrRNA RNA/DNA ratio assay (for MAP) were used. Phagolysosome fusion was evaluated by immunofluorescence, through analysis of LAMP-1 colocalization with MAP. IBD macrophages were more permissive to MAP survival than HC macrophages (a finding not evident with MAH), but did not support MAP active growth. The lower MAP CFU counts in macrophage cultures associated with Infliximab treatment were not due to increased killing, but possibly to elevation in the proportion of intracellular dormant non-culturable MAP forms, as MAP showed higher viability in those macrophages. Increased MAP viability was not related to lack of phagolysosome maturation. The predominant induction of MAP dormant forms by Infliximab treatment may explain the lack of MAP reactivation during anti-TNF therapy of CD but does not exclude the possibility of MAP recrudescence after termination of therapy.

Language: English

Type (Professor's evaluation): Scientific

No. of pages: 10