Increased expression of human leukocyte antigen-DR on pulmonary macrophages in bronchopulmonary dysplasia.
We used an immunoperoxidase method to examine the expression of the immune activation marker HLA-DR on pulmonary tissue obtained at autopsy from 14 patients dying of bronchopulmonary dysplasia. Controls consisted of 16 age-matched, sex-matched children dying of noncardiac, nonrespiratory, noninfectious illnesses or as a result of motor vehicle accidents. We did not observe aberrant expression of HLA-DR on pulmonary endothelial cells. Positive staining appeared exclusively on macrophages. We quantitated the expression of antigen by counting the number of positive macrophages and total macrophages/monocytes per high power field. Bronchopulmonary dysplasia patients displayed significantly greater numbers of both positive and total macrophages compared with the control group (p < 0.05). The percent positive macrophages also was significantly higher in the bronchopulmonary dysplasia patients (p < 0.005). We also examined a group of patients dying with infant respiratory distress syndrome. There was no significant difference in number of total macrophages in this group compared with age-matched controls.
Jacobson
J D
JD
Developmental Endocrinology Branch, National Institute of Child Health and Human Development, National Institutes of Health, Bethesda, Maryland 20892.
Truog
W E
WE
Benjamin
D R
DR
D001997:Bronchopulmonary Dysplasia / Q000276:immunology / Q000473:pathology*; D002452:Cell Count; D002675:Child, Preschool; D005260:Female; D005865:Gestational Age; D006684:HLA-DR Antigens / Q000096:biosynthesis*; D006801:Humans; D007124:Immunoenzyme Techniques; D007223:Infant; D007231:Infant, Newborn; D008262:Macrophage Activation; D016676:Macrophages, Alveolar / Q000378:metabolism* / Q000473:pathology; D008297:Male
D006684:HLA-DR Antigens