Cysteinyl leukotriene receptor 1 expression identifies a subset of neutrophils during the antiviral response that contributes to postviral atopic airway disease.

Background: Viral respiratory tract infections increase the risk of development and exacerbation of atopic disease. Previously, we demonstrated the requirement for a neutrophil (PMN) subset expressing CD49d to drive development of postviral atopic airway disease in mice.

Objective: We sought to determine whether human CD49d PMNs are present in the nasal mucosa during acute viral respiratory tract infections and further characterize this PMN subset in human subjects and mice.

Heiner syndrome mimicking an immune deficiency.

Heiner syndrome is a rare but reversible non-IgE mediated hypersensitivity to cow's milk resulting in an atypical pulmonary disease in infants and young children. There isoften a delay in diagnosis in this disorder due to its unusual presentation with heterogeneous manifestations. Such infants usually have chronic or recurrent upper or lower respiratory tract symptoms, suggestive of recurring infections such as otitis media or pneumonia.