title: Over-expression of hsp-70 inhibits bacterial lipopolysaccharide-induced production of cytokines in human monocyte-derived macrophages.
abstract: Cytokines released from monocytes and macrophages are major mediators of inflammation. Heat shock significantly inhibits cytokine production from these cells. To investigate whether this inhibitory effect was mediated by heat-shock proteins (HSP), we transfected human peripheral blood monocyte-derived macrophages (MDM) with HSP-70 cDNA and examined Brucella melitensis lipopolysaccharide (LPS)-induced cytokine production in transfected cells. Over-expression of HSP-70 protein in the gene-transfected MDM had no effect on cytokine synthesis unless LPS was added. LPS-induced increases in production of tumour necrosis factor alpha (TNF-alpha), interleukin 1beta (IL-1beta), IL-10 and IL-12 were significantly inhibited by the over-expression of HSP-70. However, over-expression of HSP-70 did not block LPS-induced increase in IL-6 synthesis. To further confirm these results, an antisense HSP-70 DNA oligomer was used to block HSP-70 synthesis. The inhibitory effect of HSP-70 on LPS-induced cytokine production in gene- transfected cells was completely reversed after treatment of cells with 5 microM antisense HSP-70. The same concentration of antisense HSP-70 also partially reversed heat-shock-induced inhibition of LPS-stimulated cytokine production. These results suggest that HSP-70 is involved in the regulation of LPS-induced cytokine production and that this family of proteins plays a role in mitigating adverse effects of endotoxin during infection or other pathological stresses.
authors.affiliation: Department of Bacterial Diseases, Walter Reed Army Institute of Research, Washington, DC 20307-5100, USA.
authors.forename: X Z
authors.initials: XZ
authors.lastname: Ding
authors.forename: C M
authors.initials: CM
authors.lastname: Fernandez-Prada
authors.forename: A K
authors.initials: AK
authors.lastname: Bhattacharjee
authors.forename: D L
authors.initials: DL
authors.lastname: Hoover
mesh_terms: D015153:Blotting, Western; D016207:Cytokines / Q000096:biosynthesis*; D004797:Enzyme-Linked Immunosorbent Assay; D005434:Flow Cytometry; D018840:HSP70 Heat-Shock Proteins / Q000096:biosynthesis*; D006801:Humans; D007375:Interleukin-1 / Q000096:biosynthesis; D016753:Interleukin-10 / Q000096:biosynthesis; D018664:Interleukin-12 / Q000096:biosynthesis; D008070:Lipopolysaccharides / Q000378:metabolism*; D008264:Macrophages / Q000378:metabolism*; D008856:Microscopy, Fluorescence; D009000:Monocytes / Q000378:metabolism*; D016376:Oligonucleotides, Antisense / Q000494:pharmacology; D020133:Reverse Transcriptase Polymerase Chain Reaction; D013997:Time Factors; D014158:Transcription, Genetic; D014162:Transfection; D014409:Tumor Necrosis Factor-alpha / Q000096:biosynthesis
chemical_list: D016207:Cytokines; D018840:HSP70 Heat-Shock Proteins; D007375:Interleukin-1; D008070:Lipopolysaccharides; D016376:Oligonucleotides, Antisense; D014409:Tumor Necrosis Factor-alpha; D016753:Interleukin-10; D018664:Interleukin-12