Biomaterial Database

Bronchus-associated lymphoid tissue (BALT) in human fetal and infant lung. 1993

S J Gould, and P G Isaacson

Department of Histopathology, Middlesex School of Medicine, University College London, U.K.

Bronchus-associated lymphoid tissue (BALT) has been defined as the organized lymphoid tissue of the lung. Although well described in a variety of animal species, documentation of its presence and development in human lung is limited. Because the tissue to volume ratio in adult lungs is so low, a systematic search for BALT would involve so many sections as to be impractical. In this study, therefore, we have studied post-mortem specimens of fetal (n = 102) and infant (n = 17) lungs, which have a much higher tissue to volume ratio. Fetal death was due to various causes but all but two infants died from sudden infant death syndrome. In the fetal lungs, the presence of BALT was almost invariably associated with chorioamnionitis or intrauterine pneumonia, being present in 24 of 51 of these cases (47 per cent). The earliest ill-defined lymphoid aggregate was seen at 16 weeks' gestation, while lymphoepithelium, a hallmark of mucosa-associated lymphoid tissue, could be identified at 20 weeks. In 51 fetuses without infection, BALT was found in only five cases (10 per cent). BALT was identified in 13/17 (77 per cent) of infant lungs and well-developed lymphoepithelium was evident in four cases. This study shows that BALT may be present in the human fetal and infant lung, but that its appearance is probably dependent on antigenic stimulation.

UI	MeSH Term	Description	Entries
D007223	Infant	A child between 1 and 23 months of age.	Infants
D008168	Lung	Either of the pair of organs occupying the cavity of the thorax that effect the aeration of the blood.	Lungs
D008171	Lung Diseases	Pathological processes involving any part of the LUNG.	Pulmonary Diseases,Disease, Pulmonary,Diseases, Pulmonary,Pulmonary Disease,Disease, Lung,Diseases, Lung,Lung Disease
D008221	Lymphoid Tissue	Specialized tissues that are components of the lymphatic system. They provide fixed locations within the body where a variety of LYMPHOCYTES can form, mature and multiply. The lymphoid tissues are connected by a network of LYMPHATIC VESSELS.	Lymphatic Tissue,Lymphatic Tissues,Lymphoid Tissues,Tissue, Lymphatic,Tissue, Lymphoid,Tissues, Lymphatic,Tissues, Lymphoid
D009092	Mucous Membrane	An EPITHELIUM with MUCUS-secreting cells, such as GOBLET CELLS. It forms the lining of many body cavities, such as the DIGESTIVE TRACT, the RESPIRATORY TRACT, and the reproductive tract. Mucosa, rich in blood and lymph vessels, comprises an inner epithelium, a middle layer (lamina propria) of loose CONNECTIVE TISSUE, and an outer layer (muscularis mucosae) of SMOOTH MUSCLE CELLS that separates the mucosa from submucosa.	Lamina Propria,Mucosa,Mucosal Tissue,Muscularis Mucosae,Mucous Membranes,Membrane, Mucous,Membranes, Mucous,Mucosae, Muscularis,Mucosal Tissues,Propria, Lamina,Tissue, Mucosal,Tissues, Mucosal
D001980	Bronchi	The larger air passages of the lungs arising from the terminal bifurcation of the TRACHEA. They include the largest two primary bronchi which branch out into secondary bronchi, and tertiary bronchi which extend into BRONCHIOLES and PULMONARY ALVEOLI.	Primary Bronchi,Primary Bronchus,Secondary Bronchi,Secondary Bronchus,Tertiary Bronchi,Tertiary Bronchus,Bronchi, Primary,Bronchi, Secondary,Bronchi, Tertiary,Bronchus,Bronchus, Primary,Bronchus, Secondary,Bronchus, Tertiary
D004848	Epithelium	The layers of EPITHELIAL CELLS which cover the inner and outer surfaces of the cutaneous, mucus, and serous tissues and glands of the body.	Mesothelium,Epithelial Tissue,Mesothelial Tissue,Epithelial Tissues,Mesothelial Tissues,Tissue, Epithelial,Tissue, Mesothelial,Tissues, Epithelial,Tissues, Mesothelial
D006801	Humans	Members of the species Homo sapiens.	Homo sapiens,Man (Taxonomy),Human,Man, Modern,Modern Man
D013398	Sudden Infant Death	The abrupt and unexplained death of an apparently healthy infant under one year of age, remaining unexplained after a thorough case investigation, including performance of a complete autopsy, examination of the death scene, and review of the clinical history. (Pediatr Pathol 1991 Sep-Oct;11(5):677-84)	Cot Death,Crib Death,SIDS,Death, Sudden Infant,SID,Sudden Infant Death Syndrome,Cot Deaths,Death, Cot,Death, Crib,Infant Death, Sudden