Objective:To investigate the role and possible mechanism of triggering receptor expressed on myeloid cells-1(TREM-1)in the inflammatory response of rat vascular smooth muscle cells(VSMCs)mediated by trimethylamine N-oxide(TMAO).Methods:VSMCs were treated with TMAO at different concentrations(0,100,300,600,900,1 200,1 500 μmol/L)for 24 hours.VSMCs were transfected with the siRNA interference plasmid targeting the TREM-1 gene(si-TREM-1)and its negative control interference plas-mid(si-NC),and 600 μmol/L TMAO was used to induce inflammatory response in VSMCs,combined with the intervention with the nuclear factor-kappa B(NF-κB)activator phorbol myristate acetate(PMA)for 24 hours.CCK-8 assay was used to measure cell prolif-erative activity;ELISA was used to measure the levels of interleu-kin-1β(IL-1β),interleukin-6(IL-6),and tumor necrosis factor-α(TNF-α)in cell supernatant;qRT-PCR was used to measure the mRNA expression levels of TREM-1,cyclooxygenase-2(COX-2),intercellular adhesion molecule-1(ICAM-1),IL-1β,IL-6,and TNF-α in cells,and Western blot was used to measure the protein expression levels of TREM-1,COX-2,ICAM-1,NF-κB p65,and p-NF-κB p65(Ser536)in cells.Results:Treatment with TMAO at different concentrations had no significant impact on the prolifera-tive activity of VSMCs(P=0.375),but it significantly upregulated the levels of IL-1β,IL-6,and TNF-α in supernatant and the mRNA and protein expression levels of TREM-1,COX-2,and ICAM-1 in cells(all P<0.01)in a concentration-dependent manner.Silencing of the TREM-1 gene significantly inhibited the increases in the levels of IL-1β,IL-6,and TNF-α in the supernatant of VSMCs in-duced by TMAO,and it also suppressed the upregulation of the mRNA expression levels of COX-2,ICAM-1,IL-1β,IL-6,and TNF-α and the ratio of p-NF-kB p65/NF-kB p65 in VSMCs(all P<0.01).However,PMA intervention significantly reversed the role of si-lencing the TREM-1 gene on TMAO-induced inflammatory response in VSMCs.Conclusion:Silencing of the TREM-1 gene can in-hibit TMAO-induced inflammatory response in VSMCs,possibly by inhibiting the activation of the NF-κB pathway.

INTRODUCTIONAnti-BP180 IgG titres were observed to parallel disease activity in case series of bullous pemphigoid (BP). This study aimed to examine whether anti-BP180 titres are an indicator of disease severity, clinical course and outcome in Asian patients with BP.

MATERIALS AND METHODSThis was a prospective observational study conducted between March 2005 and March 2008 in the Immunodermatology Clinic at the National Skin Centre, Singapore. Disease activity and anti-BP180 IgG titres were measured 4-weekly for 12 weeks and during disease flares and clinical remission. Associations between anti-BP180 titres and disease activity, disease flare, clinical remission and cumulative prednisolone dose were examined.

RESULTSThirty-four patients with newly diagnosed BP were recruited. Median follow-up duration was 3 years. Notable correlations between disease activity and anti-BP180 titres were at baseline (r = 0.51, P = 0.002), and disease flare (r = 0.85, P <0.001). Lower titres at Week 12 were associated with greater likelihood of clinical remission (P = 0.036). Post hoc, patients with anti-BP180 titres above 87.5 U/mL at time of diagnosis who reached remission within 2 years of diagnosis received significantly higher cumulative doses (mg/kg) of prednisolone (median, 72.8; range, 56.5 to 127.1) than those with titres <87.5 U/mL (median, 44.6; range, 32.5 to 80.8); P = 0.025).

CONCLUSIONAnti-BP180 titres may be a useful indicator of disease activity at time of diagnosis and at disease flare. Lower titres at Week 12 may predict greater likelihood of clinical remission. Titres above 87.5 U/mL at time of diagnosis may suggest the need for higher cumulative doses of prednisolone to achieve remission within 2 years.

Adult ; Aged ; Aged, 80 and over ; Antibodies, Anti-Idiotypic ; blood ; Asian Continental Ancestry Group ; Autoantibodies ; blood ; Autoantigens ; blood ; Disease Progression ; Enzyme-Linked Immunosorbent Assay ; Female ; Humans ; Male ; Middle Aged ; Non-Fibrillar Collagens ; blood ; Outcome Assessment (Health Care) ; Pemphigoid, Bullous ; diagnosis ; ethnology ; immunology ; Predictive Value of Tests ; Prospective Studies ; Singapore