Infection of human lung fibroblasts with Epstein-Barr virus causes increased IL-1beta and bFGF production

Epstein-Barr Virus Promotes Inflammatory Cytokine Production in Human Gingival Fibroblasts

BACKGROUND

Periodontitis is one of the most common chronic oral inflammatory diseases. Over the past decade, herpes viruses, particularly Epstein-Barr virus (EBV), have been considered promising pathogenic candidates for periodontitis. However, the specific mechanism by which EBV contributes to the development of periodontitis is still unknown. This study aimed to explore the mechanism of EBV underlying the inflammatory response in human gingival fibroblasts (HGFs).

MATERIALS AND METHODS

HGFs were stimulated with different concentrations of EBV (104, 105, 106, 107, and 108 DNA copies/mL) for 0, 8, 24, or 48 hours. The mRNA levels of interleukin (IL)-1β, tumour necrosis factor-α (TNF-α), IL-8, monocyte chemoattractant protein-1 (MCP-1), and Toll-like receptor 9 (TLR9) were measured using quantitative real-time polymerase chain reaction (PCR). Enzyme-linked immunosorbent assays (ELISAs) were performed for determining the mRNA and protein levels of IL-1β, TNF-α, IL-8, and MCP-1. Real-time PCR and ELISA were performed to determine the protein levels of IL-1β, TNF-α, IL-8, and MCP-1. Activation of the TLR9/myeloid differentiation factor 88 (MyD88)/nuclear factor kappa B (NF-κB) pathway was evaluated using western blotting.

RESULTS

The expressions of IL-1β, TNF-α, IL-8, and MCP-1 were significantly upregulated in HGFs under EBV stimulation in a concentration- and time-dependent manner. EBV promoted TLR9 and MyD88 expression and induced NF-κB transcription. On the contrary, the upregulation of these factors and the activation of NF-κB pathway were drastically inhibited by TLR9 antagonists.

CONCLUSIONS

Our findings demonstrate that EBV promotes the production of inflammatory cytokines IL-1β and TNF-α and chemokines IL-8 and MCP-1 in HGFs through the TLR9/MyD88/NF-κB pathway.

Fresh Insights into Disease Etiology and the Role of Microbial Pathogens

Pathogens have been implicated in the initiation and/or promotion of systemic sclerosis (scleroderma, SSc); however, no evidence was found to substantiate the direct contribution to this disease in past years. Recently, significant advances have been made in understanding the role of the innate immune system in SSc pathogenesis, supporting the idea that pathogens might interact with host innate immune-regulatory responses in SSc. In light of these findings, we review the studies that identified the presence of pathogens in SSc, along with studies on pathogens implicated in driving the innate immune dysregulation in SSc. The goal of this review is to illustrate how these pathogens, specifically viruses, may play important role both as triggers of the innate immune system, and critical players in the development of SSc disease.

[Vasculitis and diffuse panbronchiolitis-like in systemic lupus erythematosus--case report]

Visceral involvement in systemic lupus erythematosus (SLE) extends beyond renal and cutaneous management. Pleuro-pulmonary lesions have been recognised and diffuse alveolar damage and hemorrhage are the most difficult patterns to control. Pulmonary compromise in clinical evolution of SLE differs from children to adults, both in morphological patterns and in clinical presentation, depending on immunocompetence and the treatment prescribed. A 16-year-old boy presented asthenia, malaise and bilateral cervical painless adenopathies understood as EBV infection as serological EBV IgG, IgM and EBNA were positive. The symptoms persisted for eight months when discrete erythematous and desquamative nasal and malar rash expressed together with persistent fever, dispnoea and bibasilar crackles. Lymph node and pulmonary biopsies were performed. Lymph node presented follicular hyperplasia and LMP1 (EBV) immunostaining was negative. In lung biopsy bronchovascular lesions were consistent with vasculitis and bronchiolitis due to intense macrophage infiltration, validated with CD68 antibody and intra-alveolar macrophages were also present with septal compromise; LMP1 (EBV) positive cells were not visualized. The lung pattern seen in CAT as diffuse micronodules all over the lung parenchyme resolved after corticosteroid therapy. The diagnosis of SLE was confirmed by ANA, anti-dsDNA, anti-nDNA and anti-histones positivity. To the best of our knowledge this is the first reported case of pulmonary SLE involvement with vasculitis and diffuse panbronchiolitis - like pattern as the first clinical sign of the disease.