Better models of translational biological systems are continually being sought by the biomedical research community. In comparison to animal models or immortalized cell models, human primary cells demonstrate increased physiological relevance in terms of response, efficacy, and toxicity
(Hynds, 2013). In particular, reliable and accurate models of lung function are highly sought after to model lung function and to facilitate drug discovery (Abbott, 2015; Chen, 2017).

The respiratory system is comprised of the organs and tissues necessary for breathing, including the lungs. The primary role of the lungs is gas exchange – that is, inhalation of oxygen-rich air and removal of carbon dioxide waste. Throughout the human respiratory system is a continuous layer of epithelial cells (e.g., bronchial, small airway, tracheal) that not only play a critical role in maintaining air flow and gas exchange, but help to provide the lungs immune defense against inhaled particulates, microbes, and pathogens (Crystal, 2008). A detailed description of the anatomy of the respiratory system and its specific functions are beyond the scope of the post, but additional online resources are freely available. 

Tissue harvested from the lungs of a healthy human emulates the intrinsic properties of the human lung in vivo. For this reason, primary human lung cell models provide an ideal method for studying the pharmacokinetic properties, toxicology, and mechanism of action of inhaled drug molecules and are commonly used to study absorption, distribution, or elimination of inhaled drugs via the pulmonary route (Min, 2016). Other applications of primary human lung cells include the study of microbial infections (e.g., bacterial, viral), wound healing, pulmonary diseases (e.g., COPD, asthma, emphysema, cancer), and airway inflammation due to inhaled environmental or occupational pollutants, irritants, and allergens.

In addition to traditional culturing techniques, researchers are now incorporating primary lung epithelial cells on microchips to better mimic the
in vivo cellular environment. These “lungs-on-a-chip” can model the structural, mechanical, absorptive, and physiological properties of the human lung, including breathing motion, air-blood barrier and air-liquid interface (Stuki, 2018). Furthermore, scientists are using targeted knockout genes in
primary human airway epithelial cells (e.g., CRISPR–Cas9-mediated genome-editing) to study gene function, molecular mechanisms underlying human pulmonary diseases, and immune response to pathogens and pollutants (Chu, 2015). Thus, the use of human primary cell models are valuable tools to examine the mechanisms of the intact lung under normal or diseased conditions (Min, 2016).

Prior to initiating a study with human primary lung cells, researchers should conduct due diligence to identify a supplier that is reliable, has an established organ procurement network, and is experienced in providing high-quality cell lines. Novabiosis is a leading provider of several cryopreserved human cells from multiple organ types for research applications, drug discovery, and drug development.

Novabiosis offers a wide selection of proliferating primary human lung cells from different locations in the lung (i.e., bronchus, small airways, trachea), all harvested from normal, healthy donors. These cell types include bronchial epithelial cells (NhBe-P0), small airway epithelial cells (NhSea-P0), and tracheal epithelial cells (NhTe-P0). The cell composition for each cell type consists of ciliated, non-ciliated, goblet, and basal cells. When each of these cell types are cultured, they create homogenous basal cell populations known as bronchial epithelial cells (NhBE-P1), small airway epithelial cells (NhSea-P1), and tracheal epithelial cells (NhTe-P1).Primary human lung cells provide an ideal model for drug screening and development, toxicological testing of air pollutants, and to study many aspects of human pulmonary function and pathophysiology.