Mycobacterium bovis BCG cell wall-specific differentially expressed genes identified by differential display and cDNA subtraction in human macrophages.
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.
Begum
Nasim A
NA
Department of Immunology, Osaka Medical Center for Cancer and Cardiovascular Diseases, Higashinari-ku, Osaka 537-8511, Japan.
Ishii
Kazuo
K
Kurita-Taniguchi
Mitsue
M
Tanabe
Masako
M
Kobayashi
Mika
M
Moriwaki
Yasuhiro
Y
Matsumoto
Misako
M
Fukumori
Yasuo
Y
Azuma
Ichiro
I
Toyoshima
Kumao
K
Seya
Tsukasa
T
D000276:Adjuvants, Immunologic / Q000494:pharmacology*; D001483:Base Sequence; D017358:Cell Wall Skeleton / Q000494:pharmacology*; D016207:Cytokines / Q000235:genetics; D003713:Dendritic Cells / Q000502:physiology; D020869:Gene Expression Profiling; D015723:Gene Library; D006801:Humans; D008070:Lipopolysaccharides / Q000494:pharmacology; D008264:Macrophages / Q000378:metabolism*; D008562:Membrane Glycoproteins / Q000235:genetics; D008565:Membrane Proteins / Q000235:genetics; D008969:Molecular Sequence Data; D009000:Monocytes / Q000378:metabolism; D009163:Mycobacterium bovis / Q000276:immunology*; D020411:Oligonucleotide Array Sequence Analysis; D011956:Receptors, Cell Surface / Q000235:genetics; D011971:Receptors, Immunologic / Q000235:genetics; D051195:Toll-Like Receptor 2; D051197:Toll-Like Receptor 4; D051193:Toll-Like Receptors; D014158:Transcription, Genetic; D000073871:Triggering Receptor Expressed on Myeloid Cells-1
D000276:Adjuvants, Immunologic; C042138:BCG lipopolysaccharide; D017358:Cell Wall Skeleton; D016207:Cytokines; D008070:Lipopolysaccharides; D008562:Membrane Glycoproteins; D008565:Membrane Proteins; D011956:Receptors, Cell Surface; D011971:Receptors, Immunologic; C495342:TLR2 protein, human; C495345:TLR4 protein, human; C408842:TREM1 protein, human; D051195:Toll-Like Receptor 2; D051197:Toll-Like Receptor 4; D051193:Toll-Like Receptors; D000073871:Triggering Receptor Expressed on Myeloid Cells-1