Trace Levels of Staphylococcal Enterotoxin Bioactivity Are Concealed in a Mucosal Niche during Pulmonary Inflammation

[Etiological significance and antibioticosensetivity of certain microorganisms in aggravation of chronical bronchopulmonary pathology in workers of diverse economic sectors.]

It has been shown that in patients with upper respiratory diseases of occupational etiology gram negative flora prevail (38% of cases). They are followed by yeast-like fungi (up to 36% of cases), gram positive flora - 26%. The most effective antibacterial agents for treating golden staphilococcus in patients of the group studied are cefotaxime, sparfloxacine, levofloloxacine. Cefotoxime, ceftriaxon, ciprofloxacine are used against intestinal bacteria. Cefepim, ceftazidim are used against non-fermenting gram negative bacteria. C.Albicans can be treated with amfotericine and fluconazol.

T cell-directed IL-17 production by lung granular γδ T cells is coordinated by a novel IL-2 and IL-1β circuit

Immune-mediated lung is considered the result of an exacerbated innate injury immune response, although a role for adaptive lymphocytes is emerging. αβ T cells specific for S. aureus enterotoxin A orchestrate a Tγδ17 response during lung injury. However, the mechanism driving IL-17 production is unclear. Here, we show a role for IL-2 triggering IL-17 production by lung granular γδ T cells as IL-17 synthesis and neutrophil recruitment was reduced by IL-2 blocking mAbs in vitro and in vivo. Mass cytometry analysis revealed that lung γδ T cells responded directly to IL-2 as evident from STAT5 phosphorylation and RoRγt expression. IL-2 receptor blocking mAbs and JAK inhibition impaired STAT5 phosphorylation and IL-17 release. Moreover, inhalation of S. aureus enterotoxin A induced IL-2 secretion and caspase-1-dependent IL-1β activation to drive IL-17 production. This T-cell-mediated inflammasome-dependent IL-17 response is maximum when lung Tγδ17 cells were sequentially stimulated first with IL-2 then IL-1β. Interestingly, when IL-2 is given therapeutically to cancer patients it carries a known risk of lung injury that is largely indistinguishable from that seen in sepsis. Hence, this novel mechanism reveals therapeutic targets treating both acute lung injury and high-dose IL-2 toxicity in cancer.