Because of the possible involvement of cytokines in gram-negative septicemia, we investigated serum levels of tumor necrosis factor alpha, interleukin-1 beta, alpha interferon, and gamma interferon in children with gram-negative sepsis and purpura fulminans. We studied 55 patients (ages, 1 month to 19 years) with a clinical diagnosis of sepsis and purpuric lesions who were in shock or had three or more other biologic risk factors. The mortality rate was correlated with the number of risk factors present on admission to the hospital (P = 0.03). Tumor necrosis factor alpha was elevated in 91 percent of the 35 patients tested, interleukin-1 in 21 percent of the 33 patients tested, and gamma interferon in 19 percent of the 32 tested. Alpha interferon levels were within normal limits in the 32 patients tested. Serum levels of tumor necrosis factor alpha were positively correlated with the number of risk factors (P less than 0.05) and negatively correlated with blood fibrinogen levels (P = 0.01). Tumor necrosis factor alpha, interleukin-1, and gamma interferon were significantly higher in patients who died than in the survivors. Alpha interferon levels were similar in the two groups. Serum concentrations of both interleukin-1 and gamma interferon were correlated with concentrations of tumor necrosis factor alpha. These data provide evidence that serum levels of tumor necrosis factor alpha, interleukin-1, and gamma interferon correlate with the severity of meningococcemia in children. The findings may have implications for new therapeutic approaches.

Tumor necrosis factor-␣ (TNF-␣) and interleukin-1␤ (IL-1␤), essential components in the pathogenesis of immunoinflammatory diseases, are strongly induced in monocytes by direct contact with stimulated T lymphocytes. This study demonstrates that adult human serum (HS) but not fetal calf or cord blood serum displays inhibitory activity toward the contact-mediated activation of monocytes by stimulated T cells, decreasing the production of both TNF-␣ and IL-1␤. Fractionation of HS and N-terminal microsequencing as well as electroelution of material subjected to preparative electrophoresis revealed that apolipoprotein A-I (apo A-I), a "negative" acute-phase protein, was the inhibitory factor. Functional assays and flow cytometry analyses show that highdensity lipoprotein (HDL)-associated apo A-I inhibits contact-mediated activation of monocytes by binding to stimulated T cells, thus inhibiting TNF-␣ and IL-1␤ production at both protein and messenger RNA levels. Furthermore, apo A-I inhibits monocyte inflammatory functions in peripheral blood mononuclear cells activated by either specific antigens or lectins without affecting cell proliferation. These results demonstrate a new antiinflammatory activity of HDL-associated apo A-I that might have modulating functions in nonseptic conditions. Therefore, because HDL has been shown to bind and neutralize lipopolysaccharide, HDL appears to play an important part in modulating both acute and chronic inflammation. IntroductionTumor necrosis factor-␣ (TNF-␣) and interleukin-1␤ (IL-1␤) are strongly induced in monocytes by direct contact with stimulated T lymphocytes, both cells involved in immunoinflammatory diseases such as rheumatoid arthritis, multiple sclerosis, systemic lupus erythematosus, and atherosclerosis. The importance of TNF-␣ and IL-1 in chronic inflammation has been well established. Based on the premise that T lymphocytes play a pivotal role in the pathogenesis of chronic inflammatory diseases, we demonstrated that direct cell-cell contact with stimulated T lymphocytes is a major stimulus triggering the production of large amounts of TNF-␣ and IL-1␤ in monocytes. [1][2][3] Various stimuli are able to induce T cells to activate monocytes by direct cellular contact: (1) mitogens, for example, a combination of phytohemagglutinin (PHA) and phorbol myristate acetate (PMA), 1,4-6 (2) cross-linking of CD3 by immobilized anti-CD3 monoclonal antibody (mAb) with or without cross-linking of the costimulatory molecule CD28, 7,8 (3) antigen-recognition on antigen-specific T-cell clones, 8 and (4) cytokines. 9 The identity of the ligands on plasma membrane of stimulated T cells that trigger the signaling of monocytemacrophages as well as that of the counter-ligands on monocytes is still elusive. However, in the human system some of the signaling may be attributed to ␤ 2 -integrins, CD69, CD23, CD40-CD40L and lymphocyte activation gene-3 (LAG-3). 1,4,5,10-14 Membrane-associated TNF-␣ and IL-1 do not play a crucial part in this cellular interaction, contrasting with their sign...

Our data suggest that there is a marked increase in anti-TNF activity and a decrease of antioxidant defense in patients at risk of developing multiple organ failure. The predictive value of plasma concentrations of circulating TNF-soluble receptors and vitamin C in this type of patient needs further evaluation.

These results suggest that anti-ApoA-1 IgG might be associated with increased atherosclerotic plaque vulnerability in humans and mice.

Intrapulmonary activation of leukocytes and release of cellular mediators and enzymes are involved in the pathophysiology of the adult respiratory distress syndrome (ARDS). To investigate a possible role of local cytokines, we measured bronchoalveolar fluid (BALF) and plasma levels of tumor necrosis factor alpha (TNF-alpha) and its soluble inhibitors (sTNF-RI + RII), interleukin-1 beta (IL-1 beta), interferon-alpha (IFN-alpha), and granulocyte elastase in 14 patients at risk for ARDS and in 35 patients developing ARDS after trauma, sepsis, or shock. During clinical development of severe ARDS, BALF cytokines increased markedly: TNF-alpha from 116 +/- 36 to 10,731 +/- 5,048 pg/ml (mean +/- SEM), p = 0.001; sTNF-RI + RII from 3.7 +/- 1.4 to 24.6 +/- 2.6 ng/ml, p less than 0.05; and IL-1 beta from 7,746 +/- 5,551 to 42,255 +/- 19,176 pg/ml, p = 0.01. Plasma cytokines were not increased in most patients, nor were they correlated with the development or severity of ARDS. BALF elastase was higher in patients developing ARDS than in those at risk but not going into pulmonary failure (0.97 +/- 0.26 versus 0.28 +/- 0.13 U/ml, p = 0.026), and the highest values were observed in the early stages of severe ARDS (1.85 +/- 0.39 U/ml). BALF elastase levels correlated with IFN-alpha (r = 0.72, p less than 0.001). In conclusion, local release of TNF-alpha and IL-1 beta, possibly by pulmonary macrophages or other cells, and/or accumulation in the lung is associated with the development of ARDS.(ABSTRACT TRUNCATED AT 250 WORDS)

Objective-To determine the prevalence of myositis specific autoantibodies (MSAs) and several myositis associated autoantibodies (MAAs) in a large group of patients with myositis. Methods-A total of 417 patients with myositis from 11 European countries (198 patients with polymyositis (PM), 181 with dermatomyositis (DM), and 38 with inclusion body myositis (IBM)) were serologically analysed by immunoblot, enzyme linked immunosorbent assay (ELISA) and/or immunoprecipitation. Results-Autoantibodies were found in 232 sera (56%), including 157 samples (38%) which contained MSAs. The most commonly detected MSA was anti-Jo-1 (18%). Other anti-synthetase, anti-Mi-2, and anti-SRP autoantibodies were found in 3%, 14%, and 5% of the sera, respectively. A relatively high number of anti-Mi-2 positive PM sera were found (9% of PM sera). The most commonly detected MAA was anti-Ro52 (25%). Anti-PM/Scl-100, anti-PM/Scl-75, anti-Mas, anti-Ro60, anti-La, and anti-U1 snRNP autoantibodies were present in 6%, 3%, 2%, 4%, 5%, and 6% of the sera, respectively. Remarkable associations were noticed between anti-Ro52 and anti-Jo-1 autoantibodies and, in a few sera, also between anti-Jo-1 and anti-SRP or anti-Mi-2 autoantibodies. Conclusions-The incidence of most of the tested autoantibody activities in this large group of European patients is in agreement with similar studies of Japanese and American patients. The relatively high number of PM sera with anti-Mi-2 reactivity may be explained by the use of multiple recombinant fragments spanning the complete antigen. Furthermore, our data show that some sera may contain more than one type of MSA and confirm the strong association of anti-Ro52 with anti-Jo-1 reactivity.

In MI patients, anti-apoA-1 IgG is independently associated with MACE at 1-year, interfering with a currently unknown aldosterone-dependent RHR determinant. Knowing whether anti-apoA-1 IgG assessment could be of interest to identify an MI patient subset susceptible to benefit from apoA-1/IVIG therapy remains to be demonstrated.

Objectives: To validate the diagnostic accuracy of a Euroimmun SARS-CoV-2 IgG and IgA immunoassay for COVID-19. Methods: In this unmatched (1:2) case-control validation study, we used sera of 181 laboratoryconfirmed SARS-CoV-2 cases and 326 controls collected before SARS-CoV-2 emergence. Diagnostic accuracy of the immunoassay was assessed against a whole spike protein-based recombinant immunofluorescence assay (rIFA) by receiver operating characteristic (ROC) analyses. Discrepant cases between ELISA and rIFA were further tested by pseudo-neutralization assay. Results: COVID-19 patients were more likely to be male and older than controls, and 50.3% were hospitalized. ROC curve analyses indicated that IgG and IgA had high diagnostic accuracies with AUCs of 0.990 (95% Confidence Interval [95%CI]: 0.983-0.996) and 0.978 (95%CI: 0.967-0.989), respectively. IgG assays outperformed IgA assays (p¼0.01). Taking an assessed 15% inter-assay imprecision into account, an optimized IgG ratio cutoff > 2.5 displayed a 100% specificity (95%CI: 99-100) and a 100% positive predictive value (95%CI: 96-100). A 0.8 cutoff displayed a 94% sensitivity (95%CI: 88-97) and a 97% negative predictive value (95%CI: 95-99). Substituting the upper threshold for the manufacturer's, improved assay performance, leaving 8.9% of IgG ratios indeterminate between 0.8-2.5. Conclusions: The Euroimmun assay displays a nearly optimal diagnostic accuracy using IgG against SARS-CoV-2 in patient samples, with no obvious gains from IgA serology. The optimized cutoffs are fit for rulein and rule-out purposes, allowing determination of whether individuals in our study population have