Differential expression of tumor necrosis factor receptor subtypes on leukocytes in systemic inflammatory response syndrome

Serum S100A8/A9 and S100A12 Levels in Children With Polyarticular Forms of Juvenile Idiopathic Arthritis: Relationship to Maintenance of Clinically Inactive Disease During Anti-Tumor Necrosis Factor Therapy and Occurrence of Disease Flare After Discontinuation of Therapy

OBJECTIVE

To determine the relationship between serum levels of S100A8/A9 and S100A12 and the maintenance of clinically inactive disease during anti-tumor necrosis factor (anti-TNF) therapy and the occurrence of disease flare following withdrawal of anti-TNF therapy in patients with polyarticular forms of juvenile idiopathic arthritis (JIA).

METHODS

In this prospective, multicenter study, 137 patients with polyarticular-course JIA whose disease was clinically inactive while receiving anti-TNF therapy were enrolled. Patients were observed for an initial 6-month phase during which anti-TNF treatment was continued. For those patients who maintained clinically inactive disease over the 6 months, anti-TNF was withdrawn and they were followed up for 8 months to assess for the occurrence of flare. Serum S100 levels were measured at baseline and at the time of anti-TNF withdrawal. Spearman's rank correlation test, Mann-Whitney U test, Kruskal-Wallis test, receiver operating characteristic (ROC) curve, and Kaplan-Meier survival analyses were used to assess the relationship between serum S100 levels and maintenance of clinically inactive disease and occurrence of disease flare after anti-TNF withdrawal.

RESULTS

Over the 6-month initial phase with anti-TNF therapy, the disease state reverted from clinically inactive to clinically active in 24 (18%) of the 130 evaluable patients with polyarticular-course JIA; following anti-TNF withdrawal, 39 (37%) of the 106 evaluable patients experienced a flare. Serum levels of S100A8/A9 and S100A12 were elevated in up to 45% of patients. Results of the ROC analysis revealed that serum S100 levels did not predict maintenance of clinically inactive disease during anti-TNF therapy nor did they predict disease flare after treatment withdrawal. Elevated levels of S100A8/A9 were not predictive of the occurrence of a disease flare within 30 days, 60 days, 90 days, or 8 months following anti-TNF withdrawal, and elevated S100A12 levels had a modest predictive ability for determining the risk of flare within 30, 60, and 90 days after treatment withdrawal. Serum S100A12 levels at the time of anti-TNF withdrawal were inversely correlated with the time to disease flare (r = -0.36).

CONCLUSION

Serum S100 levels did not predict maintenance of clinically inactive disease or occurrence of disease flare in patients with polyarticular-course JIA, and S100A12 levels were only moderately, and inversely, correlated with the time to disease flare.

[Cytokines as biomarkers in polytraumatized patients]

BACKGROUND

Multiple trauma can lead to posttraumatic complications such as systemic inflammatory response syndrome (SIRS), multiple organ dysfunction syndrome (MODS), and sepsis. Currently, these complications are monitored using clinical and organ-specific parameters. The immune system is activated by trauma. Cytokines, which are the messenger molecules of this system, can be determined in serum. Furthermore, they are associated with the intensity of the inflammatory and anti-inflammatory reactions.

AIM

This review describes clinical studies that measured cytokines such as TNF-α, IL-1β, IL-6, IL-8, and IL-10 to prognosticate posttraumatic complications. On the other hand, IL-6 can be helpful in deciding which primary operation to perform, i.e., external fixator or intramedullary nail. Moreover, IL-6 indicates the strength of the immune reaction. Thereby, it may help in determining the optimal time for secondary surgery.

Síndrome de disfunção de múltiplos órgãos induzida por sepse: estudo experimental em ratos

RACIONAL: A principal causa de morte em pacientes com sepse em cirurgia é a síndrome de disfunção de múltiplos órgãos. Assim, modelos experimentais que simulem alterações orgânicas da sepse em humanos são necessários. OBJETIVO: Apresentar dois modelos que induzem a síndrome de disfunção de múltiplos órgãos e comparar as alterações induzidas por inoculação endovenosa de 36UE de lipopolissacarídeo ou célula viável de Escherichia coli, em relação à: mortalidade e sobrevivência; nível de lipopolissacarídeo; liberação de fator de necrose tumoral alfa; alterações hematológicas e das funções hepática e renal. MÉTODO: Este estudo teve duração de sete dias e utilizou-se nele 50 ratos Wistar machos, divididos em três grupos: controle, lipopolissacarídeo e Escherichia coli. Os grupos experimento eram inoculados e separados em dois subgrupos, com inoculação a cada 24 ou 48 horas. No sétimo dia eram procedidas coletas de sangue e análise histopatológica de fígado, rins e pulmões. RESULTADOS: Houve sobrevivência de dez animais no grupo controle; zero no bacteriano de 24 horas e seis no de 48 horas; dez no lipopolissacarídeo de 24 horas e seis no de 48 horas. Nos grupos experimentais, os níveis de lipopolissacarídeo, fator de necrose tumoral alfa, leucócitos, plaquetas, bastonetes e as alterações renais e hepáticas foram superiores ao grupo controle. Houve alterações histopatológicas no grupo bacteriano. CONCLUSÃO: Os dois modelos de sepse induziram síndrome de disfunção de múltiplos órgãos, contudo a administração de 36UE de endotoxina a cada 48 horas pode ser utilizada com vantagens sobre os demais por não induzir morte em número significativo durante o período de sete dias.

Reprogramming of circulatory cells in sepsis and SIRS

Immune status is altered in patients with sepsis or non-infectious systemic inflammatory response syndrome (SIRS). Reduced ex-vivo TNF production by endotoxin-activated monocytes has been regularly reported. This observation is reminiscent of the phenomenon of endotoxin tolerance, and the term 'leukocyte reprogramming' well defines this phenomenon. This review will outline that the hyporesponsiveness of circulating leukocytes is not a generalized phenomenon in sepsis and SIRS. Indeed, the nature of the insult (i.e. infectious versus non-infectious SIRS; under anesthesia [surgery] or not [trauma, burn]), the nature of the activator used to trigger leukocytes (i.e. different Toll-like receptor ligands or whole bacteria), the nature of the cell culture (i.e. isolated monocytes versus peripheral blood mononuclear cells versus whole blood assays), and the nature of the analyzed cytokines (e.g. IL-1beta versus IL-1ra; TNF versus IL-10) have a profound influence on the outcome of the response.

The clinical usefulness of the measurement of cytokines

The utilization of accurate and sensitive methods for the measurement of cytokines in body fluids is prerequisite for the proper use of these mediators in clinical practice. Many factors contribute to the complexity of cytokine quantitation. Bioassays historically preceded immunoassays, which are now very popular, but there is a need for standardization. Nevertheless, due to the local effects of cytokines, the study of their blood levels is of limited value for an understanding of the pathophysiology of these mediators. This explains the development of alternative approaches to assess the ability of cells to produce cytokines. These include the Enzyme-Linked Immuno Spot Assay (ELISPOT), the measurement of cell-associated cytokines by flow cytometry, and the study of cytokine secretion by isolated peripheral blood mononuclear cells or by whole blood test. All these techniques, associated with a local detection of cytokines by immunohistochemistry or in situ hybridization and reverse transcriptase polymerase chain reaction, appear to be complementary tools for a better understanding of the biology of cytokines. Selected examples of possible clinical applications related to infectious diseases, cancer, autoimmune diseases, allergy, transplantation and preclinical evaluation of drugs and biotechnology products are given.