Distribution of Clara cell secretory protein expression in the tracheobronchial airways of rhesus monkeys

Abstract

Clara cell secretory protein (CCSP) is a protective lung protein that is believed to have antioxidant, immunomodulatory, and anticarcinogenic properties; to be present in all adult mammals; and to be well conserved in rodents, humans, and nonhuman primates. The rationale for this study is to define the distribution and abundance of CCSP in the airway epithelium and lavage fluid of the adult rhesus monkey and to provide information for evaluating CCSP as a marker of Clara cells and as a biomarker of lung health. Lung tissue and lavage fluid from 3-yr-old rhesus monkeys were examined using histopathology and immunohistochemistry. Proximal bronchi, midlevel bronchi, and terminal/respiratory bronchioles were compared for immunohistochemical localization of CCSP in three-dimensional whole mounts as well as in paraffin and Araldite sections. Immunoreactive CCSP was found in nonciliated cells throughout the airway epithelium. Proximal and midlevel airways had the highest labeling. CCSP decreased in distal airways, and respiratory bronchioles had little to no CCSP. CCSP in the most distal airways was in tall cuboidal cells adjacent to the pulmonary artery. Although a large number of cells were present in the terminal bronchioles that would be classified as Clara cells based on morphology (nonciliated cells with apical protrusions), only a small number stained positively for immunoreactive CCSP. Semiquantitative analysis of Western blots indicated that changes in lavage CCSP are consistent with, and may be predictive of, overall CCSP levels in the airway epithelium in this primate species that is phylogenetically similar to humans.

Generation of multiciliated cells in functional airway epithelia from human induced pluripotent stem cells

“…The Clara cells show CC10 distributed in large secretory vesicles while retaining their NKx2.1 and FOXA2 expression (59). The goblet cells, although infrequent in number, also demonstrate specific expression of MUC5A/C, which does not colocalize in the CC10-expressing cells (Fig.…”

Persistence of silver nanoparticles in the rat lung: Influence of dose, size, and chemical composition

“…The level of silver present in the terminal bronchioles of the left lung lobe was assessed using a semi-quantitative scoring system (Coppens, 2007). Silver enhanced stained slides were blinded and scored on a scale of zero to four using the criteria described in Supplemental Table 1.…”

Gross and Subgross Anatomy of Lungs, Pleura, Connective Tissue Septa, Distal Airways, and Structural Units

“…Bisection of wet tissue has the advantage that both halves of each airway can be examined using either the same or other techniques. In addition, this dissection method allows for the identification of precise airway generations (Pinkerton et al, 1993;Peake et al, 2000; Coppens et al, 2007). Tissues examined in the SEM remain suitable for further study using LM or TEM (Bastacky et al, 1983).…”