Raised plasma concentration and ex vivo production of inflammatory chemokines in patients with systemic lupus erythematosus.

BACKGROUND: Chemokines are involved in leucocyte chemotaxis. Infiltrating leucocytes play an important role of tissue injury in systemic lupus erythematosus (SLE). OBJECTIVE: To investigate the role of inflammatory chemokines and their association with interleukin 18 (IL18) in SLE pathogenesis and disease activity. METHODS: Plasma concentrations and ex vivo peripheral blood mononuclear cell production of inflammatory chemokines IP-10, RANTES, MIG, MCP-1, TARC, IL8, and GROalpha, and proinflammatory cytokines IL18, IFNgamma, IL2, IL4, and IL10 were assayed in 80 SLE patients with or without renal disease and 40 healthy controls by immunofluorescence flow cytometry and enzyme linked immunosorbent assay. RESULTS: Plasma IP10, RANTES, MIG, MCP-1, GROalpha, and IL18 concentrations in all SLE patients were higher than in controls, and correlated significantly with SLEDAI score (all p<0.05). In SLE patients without renal disease, IP10, RANTES, MIG, MCP-1, IL8, and IL18 correlated positively with SLEDAI score, while in those with renal derangement, IP10, IL8, IL10, and IL18 correlated with disease activity (all p<0.05). Plasma IL18 concentration correlated positively with IP10, MIG, GROalpha, and IL8 in all SLE patients (all p<0.005). Mitogen induced increases in ex vivo production of IP10, MCP-1, TARC, IFNgamma, IL4, and IL10 were higher in all SLE patients regardless of their difference in disease activity (all p<0.05). Patients with renal disease had an augmented ex vivo release of RANTES. CONCLUSIONS: The correlation of raised plasma concentration and ex vivo production of inflammatory chemokines with disease activity, and their association with IL18, supports the view that chemotaxis of Th1/Th2 lymphocytes and neutrophils is important in SLE pathogenesis.

Aberrant production of soluble costimulatory molecules CTLA-4, CD28, CD80 and CD86 in patients with systemic lupus erythematosus.

OBJECTIVE: The costimulatory interactions of the B7 family molecules CD80 and CD86 on antigen-presenting cells with their T-cell counter-receptors CD28 and CTLA-4 modulate T lymphocyte-mediated immune responses in a reciprocal manner. We investigated the possible aberrant production of soluble (s) forms of the T-cell costimulatory molecules CD80, CD86, CD28 and CTLA-4 in plasma of patients with systemic lupus erythematosus (SLE), an autoimmune disease arising from T-lymphocyte dysregulation. METHODS: Plasma concentration and ex vivo production of soluble costimulatory molecules of 79 SLE patients with or without active disease and 40 sex- and age-matched healthy subjects were measured by enzyme-linked immunosorbent assay. RESULTS: Plasma sCTLA-4, sCD28, sCD80 and sCD86 concentrations of all SLE patients were significantly higher than concentrations in control subjects (all P<0.01). These increases were observed even in patients with inactive disease [SLE Disease Activity Index (SLEDAI) <3]. Plasma sCTLA-4 concentration in all SLE patients correlated significantly with SLEDAI score (r = 0.228, P = 0.043). Upon mitogen treatment of peripheral blood mononuclear cells, the percentage increases in ex vivo production of sCD28 and sCD80 and the percentage decrease in sCTLA-4 release were all significantly smaller in SLE patients with active disease than in healthy subjects (P<0.01, P<0.05 and P<0.0001, respectively). CONCLUSION: The aberrant production of soluble T-cell costimulatory molecules is important in the immunopathogenesis of SLE, which occurs by the dysregulation of T-lymphocyte costimulation. Plasma sCTLA concentration could potentially serve as a surrogate marker of SLE disease activity.

Elevation of plasma osteopontin concentration is correlated with disease activity in patients with systemic lupus erythematosus.

BACKGROUND: Osteopontin (OPN) is an extracellular matrix cell adhesion phosphoprotein with immunological activities including stimulation of macrophage chemotaxis, T-helper type 1 lymphocyte response and B-cell antibody synthesis. Overexpression of OPN has been associated with the development of the autoimmune/lymphoproliferative syndrome. METHODS: We measured the plasma concentration and ex vivo production of OPN, and the plasma proinflammatory IL-18 concentration in 54 SLE patients with or without renal impairment (RSLE group and SLE group, respectively) and 26 sex- and age-matched control (NC) subjects using an enzyme-linked immunoabsorbent assay. RESULTS: Plasma OPN concentrations were significantly higher in RSLE and SLE patients than in the NC group (both P<0.001). Increase in OPN concentration correlated positively and significantly with SLEDAI score in all SLE patients (r = 0.308, P = 0.023). The ex vivo production of OPN upon mitogen activation of peripheral blood mononuclear cells was significantly higher in the RSLE and SLE groups than in the NC group (both P<0.001). In RSLE patients, plasma OPN concentration showed a significant positive correlation with proinflammatory cytokine IL-18 concentration (r = 0.404, P = 0.037). CONCLUSION: The above results suggest that the production of OPN is associated with the inflammatory process and SLE development, and may serve as a potential disease marker of SLE.

Plasma inflammatory cytokines and chemokines in severe acute respiratory syndrome.

Severe acute respiratory syndrome (SARS) is a recently emerged infectious disease caused by a novel coronavirus, but its immunopathological mechanisms have not yet been fully elucidated. We investigated changes in plasma T helper (Th) cell cytokines, inflammatory cytokines and chemokines in 20 patients diagnosed with SARS. Cytokine profile of SARS patients showed marked elevation of Th1 cytokine interferon (IFN)-gamma, inflammatory cytokines interleukin (IL)-1, IL-6 and IL-12 for at least 2 weeks after disease onset, but there was no significant elevation of inflammatory cytokine tumour necrosis factor (TNF)-alpha, anti-inflammatory cytokine IL-10, Th1 cytokine IL-2 and Th2 cytokine IL-4. The chemokine profile demonstrated significant elevation of neutrophil chemokine IL-8, monocyte chemoattractant protein-1 (MCP-1), and Th1 chemokine IFN-gamma-inducible protein-10 (IP-10). Corticosteroid reduced significantly IL-8, MCP-1 and IP-10 concentrations from 5 to 8 days after treatment (all P < 0.001). Together, the elevation of Th1 cytokine IFN-gamma, inflammatory cytokines IL-1, IL-6 and IL-12 and chemokines IL-8, MCP-1 and IP-10 confirmed the activation of Th1 cell-mediated immunity and hyperinnate inflammatory response in SARS through the accumulation of monocytes/macrophages and neutrophils.

Electrospray ionisation mass spectrometry: principles and clinical applications.

This mini-review provides a general understanding of electrospray ionisation mass spectrometry (ESI-MS) which has become an increasingly important technique in the clinical laboratory for structural study or quantitative measurement of metabolites in a complex biological sample. The first part of the review explains the electrospray ionisation process, design of mass spectrometers with separation capability, characteristics of the mass spectrum, and practical considerations in quantitative analysis. The second part then focuses on some clinical applications. The capability of ESI-tandem-MS in measuring bio-molecules sharing similar molecular structures makes it particularly useful in screening for inborn errors of amino acid, fatty acid, purine, pyrimidine metabolism and diagnosis of galactosaemia and peroxisomal disorders. Electrospray ionisation is also efficient in generating cluster ions for structural elucidation of macromolecules. This has fostered a new and improved approach (vs electrophoresis) for identification and quantification of haemoglobin variants. With the understanding of glycohaemoglobin structure, an IFCC reference method for glycohaemoglobin assay has been established using ESI-MS. It represents a significant advancement for the standardisation of HbA1c in diabetic monitoring. With its other applications such as in therapeutic drug monitoring, ESI-MS will continue to exert an important influence in the future development and organisation of the clinical laboratory service.