Decomposition of productivity and unit costs

Labor productivity

ADAM17-Mediated Processing of TNF-α Expressed by Antiviral Effector CD8+ T Cells Is Required for Severe T-Cell-Mediated Lung Injury

Influenza infection in humans evokes a potent CD8+ T-cell response, which is important for clearance of the virus but may also exacerbate pulmonary pathology. We have previously shown in mice that CD8+ T-cell expression of TNF-a is required for severe and lethal lung injury following recognition of an influenza antigen expressed by alveolar epithelial cells. Since TNF-a is first expressed as a transmembrane protein that is then proteolytically processed to release a soluble form, we sought to characterize the role of TNF-a processing in CD8+ T-cell-mediated injury. In this study we observed that inhibition of ADAM17-mediated processing of TNF-a by CD8+ T cells significantly attenuated the diffuse alveolar damage that occurs after T-cell transfer, resulting in enhanced survival. This was due in part to diminished chemokine expression, as TNF-aprocessing was required for lung epithelial cell expression of CXCL2 and the subsequent inflammatory infiltration. We confirmed the importance of CXCL2 expression in acute lung injury by transferring influenza-specific CD8+ T cells into transgenic mice lacking CXCR2. These mice exhibited reduced airway infiltration, attenuated lung injury, and enhanced survival. Theses studies describe a critical role for TNF-a processing by CD8+ T cells in the initiation and severity of acute lung injury, which may have important implications for limiting immunopathology during influenza infection and other human infectious or inflammatory diseases

MDA5 and TLR3 Initiate Pro-Inflammatory Signaling Pathways Leading to Rhinovirus-Induced Airways Inflammation and Hyperresponsiveness

Rhinovirus (RV), a single-stranded RNA picornavirus, is the most frequent cause of asthma exacerbations. We previously demonstrated in human bronchial epithelial cells that melanoma differentiation-associated gene (MDA)-5 and the adaptor protein for Toll-like receptor (TLR)-3 are each required for maximal RV1B-induced interferon (IFN) responses. However, in vivo, the overall airway response to viral infection likely represents a coordinated response integrating both antiviral and pro-inflammatory pathways. We examined the airway responses of MDA5- and TLR3-deficient mice to infection with RV1B, a minor group virus which replicates in mouse lungs. MDA5 null mice showed a delayed type I IFN and attenuated type III IFN response to RV1B infection, leading to a transient increase in viral titer. TLR3 null mice showed normal IFN responses and unchanged viral titers. Further, RV-infected MDA5 and TLR3 null mice showed reduced lung inflammatory responses and reduced airways responsiveness. Finally, RV-infected MDA5 null mice with allergic airways disease showed lower viral titers despite deficient IFN responses, and allergic MDA5 and TLR3 null mice each showed decreased RV-induced airway inflammatory and contractile responses. These results suggest that, in the context of RV infection, binding of viral dsRNA to MDA5 and TLR3 initiates pro-inflammatory signaling pathways leading to airways inflammation and hyperresponsiveness

Listeriosis in patients receiving biologic therapies

The evolution of inflammatory diseases has radically changed since the introduction of biologic therapies, such as tumour necrosis factor alpha inhibitors (anti-TNFα). They, therefore, represent a widely used therapeutic modality. Nevertheless, post-marketing studies reveal an increased risk of infection in patients taking these drugs, especially granulomatous infections such as listeriosis. We aimed to evaluate the reported cases of listeriosis in patients treated with biologic treatments. We used the United States Food and Drug Administration (FDA) Adverse Event Reporting System (AERS) from 2004 to 2011. We also perform a literature review of previously reported cases of listeriosis in patients taking biologic therapies. We identified 266 cases of Listeria monocytogenes infection associated with biologic therapies. The majority of patients were receiving infliximab (77.1 %), followed by etanercept (11.7 %), adalimumab (9.8 %), rituximab (4.1 %), abatacept (0.4 %) and golimumab (0.4 %). Indications for the use of biologics were as follows: 47.7 % for rheumatologic diseases, 38 % for inflammatory bowel diseases, 3.4 % for haematological diseases and 10.5 % for other indications. Seventy-three percent of the patients were receiving concomitant immunosuppressant drugs, especially steroids (56 %) and methotrexate (31.6 %). The median time to the onset of infection was 184 days. Mortality rates range from 11.1 % in adalimumab-treated patients to 27.3 % in rituximab-treated patients (p = 0.7). Listeriosis is common in biologics-treated patients, especially related to infliximab use given concomitantly with other immunosuppressive therapies. Infections after treatment with biologics mostly occurred in the first year after initiating treatment