French researchers found that, among 91 premature infants born at 30 weeks who had hyaline membrane disease, those with higher keratinocyte growth factor (KGF) concentrations were protected against bronchopulmonary dysplasia (BPD), a serious neonatal condition. (BPD results from damage inflicted on the immature fetal lung by mechanical ventilation, oxygen therapy, and airway inflammatory responses during treatment for hyaline membrane disease. All infants in the study had both clinical and radiological evidence of hyaline membrane disease, which results from a deficiency of surfactant necessary for normal lung function.) KGF is a substance produced by the developing baby’s lung. It has been reported to regulate lung development, to prevent injury, and to assist and improve ventilator and oxygen-induced lung repair. The investigators suctioned secretions from the trachea of the 91 neonates within three hours of birth. Among the 36 neonates who had higher KGF concentrations during the first five days after birth, only two developed BPD. Fourteen infants had the disease, which was defined as a need for oxygen supplementation at 36 weeks postconceptual age. The research appears in the second issue for May of the American Thoracic Society’s peer-reviewed American Journal of Respiratory and Critical Care Medicine.
pH OFFERS SIMPLE TEST FOR AIRWAY INFLAMMATION
The pH of expired breath condensate offers a simple, noninvasive, inexpensive, and easily repeatable procedure to evaluate the inflammatory process in airway diseases. (A pH test is a measure of the acidity of a solution, with a pH of 7 being neutral.) Greek researchers studied 40 patients with bronchial asthma (20 with mild persistent asthma and 20 with moderate disease), 20 patients with bronchiectases (persistent abnormal widening of the bronchi); 20 patients with chronic obstructive pulmonary disease (COPD); and 10 control subjects. The researchers noted that the group’s findings confirmed their initial hypothesis that airway acidification from within the body is strongly related to the inflammatory process in the three diseases studied. However, the mechanism seems to differ between asthma, which is predominately characterized by inflammation associated with eosinophils (white blood cells active in allergic responses and infection) and COPD and bronchiectasis, which have inflammatory processes predominately associated with neutrophils (white blood cells that engulf bacteria and cellular debris). The investigators pointed out that when the inflammatory process in asthma is well controlled, the pH remains within normal limits. The research appears in the second issue for May of the American Thoracic Society’s peer-reviewed American Journal of Respiratory and Critical Care Medicine.
LUNG TRANSPLANT RECIPIENTS COULD PROFIT FROM A SIMPLE NEW TEST
The future clinical management of lung transplant recipients may be considerably improved and a deadly complication detected much earlier by performing analysis of serial T cell antigen receptors, according to investigators. This minimally invasive analysis might help to predict much sooner a dreaded and frequent complication of lung transplantation, obliterative bronchiolitis (OB). Since the immune picture of this disease is poorly understood, if physicians were able to predict OB early, they could begin potentially more effective interventions sooner. Consequently, if the new analysis is confirmed by larger studies, transplant physicians could begin treatment while the rejection process was still T cell dependent, before the development of widespread and fixed airway injury. (OB is a syndrome of often severe fiber proliferating injuries in airways and small pulmonary blood vessels that eventually affects one-half or more of long-term lung transplantation survivors.) By analyzing 24 specimens collected from 10 lung transplant recipients, these investigators were attempting to use quantitative methodologies to more completely define the T cell responses of pulmonary transplant recipients. They discovered that there are very distinct CD4+ T cell profiles between lung transplant recipients with OB and those with no evidence of rejection. The authors note that an expanded number of cloned CD4 cells are extremely rare in the absence of pathogenic immune responses. The study appears in the second issue for May of the American Thoracic Society’s peer-reviewed American Journal of Respiratory and Critical Care Medicine.
For the complete text of these articles, please see the American Thoracic Society Online Web Site at http://www.atsjournals.org. For contact information or to request a complimentary journalist subscription to ATS journals online, or if you would like to add your name to the Society’s twice monthly journal news mailing list (please select either postal or electronic delivery), contact Cathy Carlomagno at (212) 315-6442, or by e-mail at ccarlomagno@thoracic.org
Journal
American Journal of Respiratory and Critical Care Medicine