Mycobacterium bovis BCG cell wall-specific differentially expressed genes identified by differential display and cDNA subtraction in human macrophages

Begum, N.A.; Ishii, K.; Kurita-Taniguchi, M.; Tanabe, M.; Kobayashi, M.; Moriwaki, Y.; Matsumoto, M.; Fukumori, Y.; Azuma, I.; Toyoshima, K.; Seya, T.

Infection and Immunity 72(2): 937-948


ISSN/ISBN: 0019-9567
PMID: 14742539
DOI: 10.1128/iai.72.2.937-948.2004
Accession: 012337253

Download citation:  

Article/Abstract emailed within 0-6 h
Payments are secure & encrypted
Powered by Stripe
Powered by PayPal

We have analyzed the gene expression profile of monocytes in response to a highly purified cell wall fraction of Mycobacterium bovis BCG, a clinically approved adjuvant known as BCG cell wall skeleton (BCG-CWS). It is composed of mycolic acid, arabinogalactan, and peptidoglycan and confers Toll-like receptor 2 (TLR2)- and TLR4-dependent signaling that induces monocytes to differentiate into antigen-presenting cells (APCs). Here we report differential gene expression analysis with BCG-CWS-stimulated versus nonstimulated monocytes. BCG-CWS exerted massive induction of genes regulated by TLR signaling. Marked gene regulatory characteristics in BCG-CWS-stimulated cells compared to lipopolysaccharide (LPS)-stimulated cells follow. (i) Spliced mRNAs encoding soluble forms of TREM-1 and TREM-2 (recently discovered inflammatory-signal-amplifying receptors) were regulated by BCG-CWS, resulting in their differential expression. (ii) The genes for zinc-iron transporter protein (ZIP)-like family proteins HKE-1 and LIV-1 were induced exclusively by BCG-CWS. (iii) Interleukin-23 (IL-23), rather than IL-12p70, was induced by BCG-CWS, while interferon-inducible genes were induced only by LPS. By Northern and reverse transcription-PCR analyses, we confirmed the differential expression of more than 30 BCG-CWS regulatory genes, and their expression was compared with that of LPS and other known TLR ligands. A battery of genes responded rapidly and for a short time to LPS but for a long time to BCG-CWS. Structural analysis of the identified novel or hypothetical proteins revealed that some are potential candidates as signaling mediators or transcriptional regulators. Hence, BCG-CWS may profoundly modulate APC responses in a way distinct from that of LPS, leading to possible advantages for its adjuvant-active therapeutic potential.