IMPAIRED NEONATAL CEREBRAL BLOOD FLOW AUTOREGULATION IN GROUP B STREPTOCOCCAL MENINGITIS IS NOT MEDIATED BY TUMOR NECROSIS FACTOR (TNFα).• 977

Objective.To assess the association between treatment with anti-tumor necrosis factor-α (TNF-α) agents and the occurrence of hospitalizations, their causes and complications, compared to treatment with traditional disease-modifying antirheumatic drugs in patients with rheumatoid arthritis (RA), psoriatic arthritis (PsA), and ankylosing spondylitis (AS).Methods.A retrospective cohort study was conducted of patients with RA, AS, and PsA treated with anti-TNF-α agents between April 2002 and December 2007. Patients were assessed during the period of anti-TNF-α treatment (Group B) and compared to an equivalent period before initiation of anti-TNF-α therapy (Group A). All hospitalization charts were reviewed and diagnoses, comorbidities, concomitant medications, and clinical course were analyzed. Statistical analysis was performed using multivariate mixed Poisson regression.Results.In the study period of 57 months, 735 hospitalization events of 327 patients were analyzed. Statistically significant decreases were seen in the total number of hospitalization events as well as hospitalizations due to exacerbation of rheumatic diseases in Group B compared to Group A (44.4 vs 74.2 and 21.9 vs 47.5 per 100 patient-years, respectively; p < 0.0001). More infectious events (7.4 in Group B compared to 4.6 per 100 patient-years in Group A; p = 0.043) were associated with anti-TNF-α treatment, older age, and underlying disease, because patients with RA had higher rates of infections compared to patients with PsA and patients with AS.Conclusion.The overall effect of anti-TNF-α therapy was a significant decline in total hospitalization events. The decrease was more prominent in patients with RA than in patients with AS and patients with PsA, and reflected the significant decrease in hospitalizations due to rheumatic disease exacerbation. The decrease was more pronounced than the observed increase in infectious events.

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Group B Streptococcus and Streptococcus suis Capsular Polysaccharides Induce Chemokine Production by Dendritic Cells via Toll-Like Receptor 2- and MyD88-Dependent and -Independent Pathways

Infection and Immunity ◽

10.1128/iai.00113-13 ◽

2013 ◽

Vol 81 (9) ◽

pp. 3106-3118 ◽

Cited By ~ 24

Author(s):

Cynthia Calzas ◽

Guillaume Goyette-Desjardins ◽

Paul Lemire ◽

Fleur Gagnon ◽

Claude Lachance ◽

...

Keyword(s):

Dendritic Cells ◽

Tumor Necrosis Factor ◽

Tumor Necrosis ◽

Capsular Polysaccharides ◽

Toll Like Receptor ◽

Chemokine Production ◽

Content Type ◽

Toll Like Receptor 2 ◽

Group B ◽

Necrosis Factor

ABSTRACTStreptococcus agalactiae(also known as group BStreptococcus[GBS]) andStreptococcus suisare encapsulated streptococci causing severe septicemia and meningitis. Bacterial capsular polysaccharides (CPSs) are poorly immunogenic, but anti-CPS antibodies are essential to the host defense against encapsulated bacteria. The mechanisms underlying anti-CPS antibody responses are not fully elucidated, but the biochemistry of CPSs, particularly the presence of sialic acid, may have an immunosuppressive effect. We investigated the ability of highly purifiedS. suisand GBS native (sialylated) CPSs to activate dendritic cells (DCs), which are crucial actors in the initiation of humoral immunity. The influence of CPS biochemistry was studied using CPSs extracted from different serotypes within these two streptococcal species, as well as desialylated CPSs. No interleukin-1β (IL-1β), IL-6, IL-12p70, tumor necrosis factor alpha (TNF-α), or IL-10 production was observed inS. suisor GBS CPS-stimulated DCs. Moreover, these CPSs exerted immunosuppressive effects on DC activation, as a diminution of gamma interferon (IFN-γ)-induced B cell-activating factor of the tumor necrosis factor family (BAFF) expression was observed in CPS-pretreated cells. However,S. suisand GBS CPSs induced significant production of CCL3, via partially Toll-like receptor 2 (TLR2)- and myeloid differentiation factor 88 (MyD88)-dependent pathways, and CCL2, via TLR-independent mechanisms. No major influence of CPS biochemistry was observed on the capacity to induce chemokine production by DCs, indicating that DCs respond to these CPSs in a patterned way rather than a structure-dedicated manner.

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