The airway surface liquid (ASL) plays a crucial role in lung defense mechanisms, and its composition and volume are regulated by the airway epithelium. The cystic fibrosis transmembrane conductance regulator (CFTR) is abundantly expressed in a rare airway epithelial cell type called an ionocyte. Recently, we demonstrated that ionocytes can increase liquid absorption through apical CFTR and basolateral barttin/chloride channels, while airway secretory cells mediate liquid secretion through apical CFTR channels and basolateral NKCC1 transporters.
View Article and Find Full Text PDFThe volume and composition of a thin layer of liquid covering the airway surface defend the lung from inhaled pathogens and debris. Airway epithelia secrete Cl- into the airway surface liquid through cystic fibrosis transmembrane conductance regulator (CFTR) channels, thereby increasing the volume of airway surface liquid. The discovery that pulmonary ionocytes contain high levels of CFTR led us to predict that ionocytes drive secretion.
View Article and Find Full Text PDFLack of CFTR (cystic fibrosis transmembrane conductance regulator) affects the transcriptome, composition, and function of large and small airway epithelia in people with advanced cystic fibrosis (CF); however, whether lack of CFTR causes cell-intrinsic abnormalities present at birth versus inflammation-dependent abnormalities is unclear. We performed a single-cell RNA-sequencing census of microdissected small airways from newborn CF pigs, which recapitulate CF host defense defects and pathology over time. Lack of minimally affected the transcriptome of large and small airways at birth, suggesting that infection and inflammation drive transcriptomic abnormalities in advanced CF.
View Article and Find Full Text PDFLentiviral-mediated integration of a transgene cassette into airway basal cells is a strategy being considered for cystic fibrosis (CF) cell-based therapies. However, expression is highly regulated in differentiated airway cell types and a subset of intermediate basal cells destined to differentiate. Since basal stem cells typically do not express CFTR, suppressing the expression from the lentiviral vector in airway basal cells may be beneficial for maintaining their proliferative capacity and multipotency.
View Article and Find Full Text PDFSubmucosal glands (SMGs) are a prominent structure that lines human cartilaginous airways. Although it has been assumed that SMGs contribute to respiratory defense, that hypothesis has gone without a direct test. Therefore, we studied pigs, which have lungs like humans, and disrupted the gene for ectodysplasin (), which initiates SMG development.
View Article and Find Full Text PDFAm J Physiol Cell Physiol
August 2020
The pH of airway surface liquid (ASL) is a key factor that determines respiratory host defense; ASL acidification impairs and alkalinization enhances key defense mechanisms. Under healthy conditions, airway epithelia secrete base ([Formula: see text]) and acid (H) to control ASL pH (pH). Neutrophil-predominant inflammation is a hallmark of several airway diseases, and TNFα and IL-17 are key drivers.
View Article and Find Full Text PDFThe treatment or cure of HIV infection by cell and gene therapy has been a goal for decades. Recent advances in both gene editing and chimeric antigen receptor (CAR) technology have created new therapeutic possibilities for a variety of diseases. Broadly neutralizing monoclonal antibodies (bNAbs) with specificity for the HIV envelope glycoprotein provide a promising means of targeting HIV-infected cells.
View Article and Find Full Text PDF