Identification of vitamin C transporters in the human airways: a cross-sectional in vivo study.
Bottom Line: As secondary outcome measures, RTLF vitamin C concentration was measured and related to transporter expression, as well as bronchial epithelial inflammatory and goblet cells numbers.This experimental study is the first to demonstrate protein expression of GLUT2 and SVCT2 in the human bronchial epithelium.A negative correlation between SVCT2-positive goblet cells and bronchial RTLF vitamin C concentrations suggests a possible role for goblet cells in regulating the extracellular vitamin C pool.
Affiliation: Department of Public Health and Clinical Medicine, Division of Medicine/Respiratory Medicine and Allergy, Umeå University, Umeå, Sweden.Show MeSH
Related in: MedlinePlus
Mentions: Staining with GLUT1 yielded a distinct cell membrane staining, most likely attributed to lymphocytes (figure 1). Positive membrane staining for GLUT2 was observed in bronchial epithelial cells, at their apical and their basolateral aspects, with little staining evident in the underlying basal cells (figure 1). Diffuse cytoplasmic staining was also seen, with a strong positive staining associated with the nuclear membrane. No differences in GLUT1 and 2 staining were evident between the healthy and patients with asthma (table 3). Staining for GLUT3 and 4 yielded inconclusive results due to unspecific background staining (data not shown). The FACS data examining GLUT1-3 demonstrated equivalent expression in BAL-fluid macrophages (CD14+) and neutrophils (CD16+), with evidence of a significant reduction of GLUT3 (1.4-fold) in lymphocytes (CD3+) obtained from asthmatic compared to healthy subjects, online supplementary table S2.
Affiliation: Department of Public Health and Clinical Medicine, Division of Medicine/Respiratory Medicine and Allergy, Umeå University, Umeå, Sweden.