Eosinophils and allergic airway disease: There is more to the story

Center for Molecular Immunology & Infectious Disease and Department of Veterinary & Biomedical Sciences, The Pennsylvania State University, University Park, PA 16802, USA.
Trends in Immunology (Impact Factor: 10.4). 11/2009; 31(1):39-44. DOI: 10.1016/j.it.2009.10.001
Source: PubMed


The eosinophil has been perceived as a terminal effector cell in allergic airway diseases. However, recent work has shown that this multifunctional cell could be more involved in the initial stages of allergic disease development than was previously thought, particularly with regard to the ability of the eosinophil to modulate T-cell responses. In this review, we discuss recent advances that suggest that eosinophils can present antigen to naïve as well as to antigen-experienced T cells, induce T helper 2 cell development, cytokine production or both, and affect T-cell migration to sites of inflammation. These findings are changing the way that eosinophil function in disease is perceived, and represent a shift in the dogma of allergic disease development.

Download full-text


Available from: Avery August,
  • Source
    • "Blood eosinophilia is usually absent at the disease presentation [1], suggesting that the initial pathological stimulus originates at alveolar or pleural level. Both basic and applied research studies have demonstrated [10] that the selective activation of eosinophils is induced by several mediators, all of them sometimes categorized for simplicity with the most relevant of which, interleukin-5 (IL-5), i.e. with the name of the cytokine that exhibits the most specific and critical control of eosinophilic functions, including the regulation of eosinophilopoiesis in the bone marrow, the recruitment of these granulocytes to tissues, the lengthening of their survival by inhibiting apoptosis, and the differential activation and release of toxic products through their degranulation [11]. The local secretion of IL-5 and its enhanced concentration within restricted regions, detected in the broncho-alveolar lavage (BAL) fluid of patients with AEP, apparently reflects the presence of eosinophil-rich exudates in the alveoli andpleural cavity [12]. "
    [Show abstract] [Hide abstract]
    ABSTRACT: Acute eosinophilic pneumonia (AEP) is a rare febrile illness which is characterized by respiratory failure and often requires mechanical ventilation. The causes and sequence of events of this disease at a biochemical and histological level remain largely unknown. In this article we report the exceptional case, possibly unique, of a patient who developed AEP and three pneumothoraces within less than one month during her hospitalization . A 39-year-old German woman was admitted to our hospital for a laparoscopy-assisted vaginal hysterectomy under general anaesthesia. The surgical intervention was followed by peritonitis in the early postoperative course. Following anaesthesia induction with propofol/midazolam and during the prolonged therapy with several broad-spectrum antibiotics, she developed AEP and three spontaneous (one left-sided and two right-sided) pneumothoraces, the latter ones observed in quick succession. Symptoms, laboratory markers, and chest radiology significantly improved after a one-day treatment with methylprednisolone. On the whole, these pathological occurrences, together with similar cases reported in literature, can support the conclusion of possible predisposing genetic factors at the lung tissue level of AEP patients, a view that might shed new light on the pathogenesis of this disease. To provide a coherent pattern that explains the reported evidence for AEP and pneumothoraces, independently from the causative stimulus, the supposed molecular mutations could be localized in the connective tissue rather than in the epithelial cells. In order to interpret clinical and laboratory evidence, as well as to support the main conclusions, the important part of scientific research here presented can also assist physicians in making more informed decisions for the treatment of patients with pulmonary infiltrates.
    Multidisciplinary respiratory medicine 01/2014; 9(1):7. DOI:10.1186/2049-6958-9-7 · 0.15 Impact Factor
  • Source
    • "These contribute to airway inflammation and lung tissue remodeling that includes epithelial cell damage and loss, airway thickening, fibrosis and angiogenesis.7 More recent evidence suggests that in addition to their role as degranulating effector cells, eosinophils have the capacity to act as antigen-presenting, cells resulting in T cell proliferation and activation, thereby propagating inflammatory responses.8,9 "
    [Show abstract] [Hide abstract]
    ABSTRACT: Asthma is an increasingly common respiratory condition characterized by reversible airway obstruction, bronchial hyper-responsiveness and airway inflammation with a clear unmet need for more effective therapy. Eosinophilic asthma is a phenotype of the condition that features increased blood or sputum eosinophils whose numbers correlate with disease severity. Several lines of evidence are now emerging, which implicate increased persistence of eosinophils in the lungs of patients with asthma as a consequence of inhibition of and defects in the apoptotic process, together with impaired apoptotic cell removal mechanisms. This article will update our knowledge of the mechanisms controlling eosinophil apoptosis and clearance, together with evidence implicating defects in apoptosis and pro-inflammatory cell removal in asthma. Recent developments in novel therapies for asthma that target eosinophil apoptotic and/or clearance pathways will also be discussed.
    Journal of Cell Death 04/2013; 6(1):17-25. DOI:10.4137/JCD.S10818
  • Source
    • "Eosinophils have generally been regarded as terminal effector cells in allergic airway diseases; however, recent studies demonstrate their involvement in the initial stages of allergic disease development, as well [100]. Murine studies suggest eosinophils may actually drive T-cell responses as opposed to merely being driven by them. "
    [Show abstract] [Hide abstract]
    ABSTRACT: There is a growing list of viruses and bacteria associated with wheezing illness and asthma. It is well known that a few of these pathogens are strongly associated with wheezing illness and asthma exacerbations. What is not known is if early childhood infections with these pathogens cause asthma, and, if so, exactly what are the pathophysiologic mechanisms behind its development. The current consensus is respiratory infection works together with allergy to produce the immune and physiologic conditions necessary for asthma diasthesis. One link between respiratory infection and asthma may be the eosinophil, a cell that plays prominently in asthma and allergy, but can also be found in the body in response to infection. In turn, the eosinophil and its associated products may be novel therapeutic targets, or at the very least used to elucidate the complex pathophysiologic pathways of asthma and other respiratory illnesses. Together or separately, they can also be used for diagnosis, treatment and monitoring. The optimal care of a patient must take into consideration not only symptoms, but also the underlying disease mechanisms.
    01/2012; 2(1):3-14. DOI:10.5415/apallergy.2012.2.1.3
Show more