Expression of human carcinoembryonic antigen-related cell adhesion molecule 6 and alveolar progenitor cells in normal and injured lungs of transgenic mice

New CEACAM-targeting 2A3 single-domain antibody-based chimeric antigen receptor T-cells produce anticancer effects in vitro and in vivo

Recently, a breakthrough immunotherapeutic strategy of chimeric antigen receptor (CAR) T-cells has been introduced to hematooncology. However, to apply this novel treatment in solid cancers, one must identify suitable molecular targets in the tumors of choice. CEACAM family proteins are involved in the progression of a range of malignancies, including pancreatic and breast cancers, and pose attractive targets for anticancer therapies. In this work, we used a new CEACAM-targeted 2A3 single-domain antibody-based chimeric antigen receptor T-cells to evaluate their antitumor properties in vitro and in animal models. Originally, 2A3 antibody was reported to target CEACAM6 molecule; however, our in vitro co-incubation experiments showed activation and high cytotoxicity of 2A3-CAR T-cells against CEACAM5 and/or CEACAM6 high human cell lines, suggesting cross-reactivity of this antibody. Moreover, 2A3-CAR T-cells tested in vivo in the BxPC-3 xenograft model demonstrated high efficacy against pancreatic cancer xenografts in both early and late intervention treatment regimens. Our results for the first time show an enhanced targeting toward CEACAM5 and CEACAM6 molecules by the new 2A3 sdAb-based CAR T-cells. The results strongly support the further development of 2A3-CAR T-cells as a potential treatment strategy against CEACAM5/6-overexpressing cancers.

Human distal airways contain a multipotent secretory cell that can regenerate alveoli

The human lung differs substantially from its mouse counterpart, resulting in a distinct distal airway architecture affected by disease pathology in chronic obstructive pulmonary disease. In humans, the distal branches of the airway interweave with the alveolar gas-exchange niche, forming an anatomical structure known as the respiratory bronchioles. Owing to the lack of a counterpart in mouse, the cellular and molecular mechanisms that govern respiratory bronchioles in the human lung remain uncharacterized. Here we show that human respiratory bronchioles contain a unique secretory cell population that is distinct from cells in larger proximal airways. Organoid modelling reveals that these respiratory airway secretory (RAS) cells act as unidirectional progenitors for alveolar type 2 cells, which are essential for maintaining and regenerating the alveolar niche. RAS cell lineage differentiation into alveolar type 2 cells is regulated by Notch and Wnt signalling. In chronic obstructive pulmonary disease, RAS cells are altered transcriptionally, corresponding to abnormal alveolar type 2 cell states, which are associated with smoking exposure in both humans and ferrets. These data identify a distinct progenitor in a region of the human lung that is not found in mouse that has a critical role in maintaining the gas-exchange compartment and is altered in chronic lung disease.

The predicting roles of carcinoembryonic antigen and its underlying mechanism in the progression of coronavirus disease 2019

BACKGROUND

The coronavirus disease 2019 (COVID-19) has induced a worldwide epidemiological event with a high infectivity and mortality. However, the predicting biomarkers and their potential mechanism in the progression of COVID-19 are not well known.

OBJECTIVE

The aim of this study is to identify the candidate predictors of COVID-19 and investigate their underlying mechanism.

METHODS

The retrospective study was conducted to identify the potential laboratory indicators with prognostic values of COVID-19 disease. Then, the prognostic nomogram was constructed to predict the overall survival of COVID-19 patients. Additionally, the scRNA-seq data of BALF and PBMCs from COVID-19 patients were downloaded to investigate the underlying mechanism of the most important prognostic indicators in lungs and peripherals, respectively.

RESULTS

In total, 304 hospitalized adult COVID-19 patients in Wuhan Jinyintan Hospital were included in the retrospective study. CEA was the only laboratory indicator with significant difference in the univariate (P < 0.001) and multivariate analysis (P = 0.020). The scRNA-seq data of BALF and PBMCs from COVID-19 patients were downloaded to investigate the underlying mechanism of CEA in lungs and peripherals, respectively. The results revealed the potential roles of CEA were significantly distributed in type II pneumocytes of BALF and developing neutrophils of PBMCs, participating in the progression of COVID-19 by regulating the cell-cell communication.

CONCLUSION

This study identifies the prognostic roles of CEA in COVID-19 patients and implies the potential roles of CEACAM8-CEACAM6 in the progression of COVID-19 by regulating the cell-cell communication of developing neutrophils and type II pneumocyte.

Biological Functions and Identification of Novel Biomarker Expressed on the Surface of Breast Cancer-Derived Cancer Stem Cells via Proteomic Analysis

Breast cancer is one of the most common life-threatening malignancies and the top cause of cancer deaths in women. Although many conventional therapies exist for its treatment, breast cancer still has many handicaps to overcome. Cancer stem cells (CSCs) are a well-known cause of tumor recurrences due to the ability of CSCs for self-renewal and differentiation into cell subpopulations, similar to stem cells. To fully treat breast cancer, a strategy for the treatment of both cancer cells and CSCs is required. However, current strategies for the eradication of CSCs are non-specific and have low efficacy. Therefore, surface biomarkers to selectively treat CSCs need to be developed. Here, 34 out of 641 surface biomarkers on CSCs were identified by proteomic analysis between the human breast adenocarcinoma cell line MCF-7 and MCF-7-derived CSCs. Among them, carcinoembryonic antigen-related cell adhesion molecules 6 (CEACAM6 or CD66c), a member of the CEA family, was selected as a novel biomarker on the CSC surface. This biomarker was then experimentally validated and evaluated for use as a CSC-specific marker. Its biological effects were assessed by treating breast cancer stem cells (BCSCs) with short hairpin (sh)-RNA under oxidative cellular conditions. This study is the first to evaluate the biological function of CD66c as a novel biomarker on the surface of CSCs. This marker is available as a moiety for use in the development of targeted therapeutic agents against CSCs.

Measurement of Lung Cancer Tumor Markers in a Glass Wool Company Workers Exposed to Respirable Synthetic Vitreous Fiber and Dust

Background:

Occupational exposures to respirable synthetic vitreous fiber (SVF) and dust are associated with many lung diseases including lung cancer. Low-dose computed tomography is used for screening patients who are highly suspicious of having lung carcinoma. However, it seems not to be cost-effective. Serum biomarkers could be a useful tool for the surveillance of occupational exposure, by providing the possibility of diagnosing lung cancer in its early stages.

Objective:

To determine if serum carcinoembryonic antigen (CEA) and cytokeratin fragment (CYFRA) 21-1 levels in workers exposed more than normal population to respirable SVF and dust may be used as indicators of progression towards lung cancer.

Methods:

An analytic cross-sectional study, including 145 personnel of a glass wool company, along with 25 age-matched healthy individuals, was conducted to investigate the relationship between occupational exposure to respirable SVFs and dust and serum levels of two lung/pleura serum tumor markers, CEA and CYFRA 21-1, measured by ELISA.

Results:

Individuals exposed to higher than the recommended levels of respirable SVF had higher serum concentrations of CEA and CYFRA 21-1, compared to controls (p=0.008 and 0.040, respectively), as well as in comparison to those exposed to lower than recommended OSHA levels (p=0.046 and 0.033, respectively). Workers with >9 years work experience, had significantly (p=0.045) higher levels of serum CYFRA 21-1 than those with ≤9 years of experience.

Conclusion:

It seems that working for >9 years in sites with detectable levels of respirable SVF and dust would increase the levels of known lung cancer serum tumor markers. Transferring these workers to sites with respirable SVF concentrations lower than the limit of detection in the air is recommended.

Human induced pluripotent stem cell-derived lung progenitor and alveolar epithelial cells attenuate hyperoxia-induced lung injury

BACKGROUND AIMS

Bronchopulmonary dysplasia (BPD), a chronic lung disease characterized by disrupted lung growth, is the most common complication in extreme premature infants. BPD leads to persistent pulmonary disease later in life. Alveolar epithelial type 2 cells (AEC2s), a subset of which represent distal lung progenitor cells (LPCs), promote normal lung growth and repair. AEC2 depletion may contribute to persistent lung injury in BPD. We hypothesized that induced pluripotent stem cell (iPSC)-derived AECs prevent lung damage in experimental oxygen-induced BPD.

METHODS

Mouse AECs (mAECs), miPSCs/mouse embryonic stem sells, human umbilical cord mesenchymal stromal cells (hUCMSCs), human (h)iPSCs, hiPSC-derived LPCs and hiPSC-derived AECs were delivered intratracheally to hyperoxia-exposed newborn mice. Cells were pre-labeled with a red fluorescent dye for in vivo tracking.

RESULTS

Airway delivery of primary mAECs and undifferentiated murine pluripotent cells prevented hyperoxia-induced impairment in lung function and alveolar growth in neonatal mice. Similar to hUCMSC therapy, undifferentiated hiPSCs also preserved lung function and alveolar growth in hyperoxia-exposed neonatal NOD/SCID mice. Long-term assessment of hiPSC administration revealed local teratoma formation and cellular infiltration in various organs. To develop a clinically relevant cell therapy, we used a highly efficient method to differentiate hiPSCs into a homogenous population of AEC2s. Airway delivery of hiPSC-derived AEC2s and hiPSC-derived LPCs, improved lung function and structure and resulted in long-term engraftment without evidence of tumor formation.

CONCLUSIONS

hiPSC-derived AEC2 therapy appears effective and safe in this model and warrants further exploration as a therapeutic option for BPD and other lung diseases characterized by AEC injury.

A CEACAM6-High Airway Neutrophil Phenotype and CEACAM6-High Epithelial Cells Are Features of Severe Asthma

Severe asthma represents a major unmet clinical need; understanding the pathophysiology is essential for the development of new therapies. Using microarray analysis, we previously found three immunological clusters in asthma: Th2-high, Th17-high, and Th2/17-low. Although new therapies are emerging for Th2-high disease, identifying molecular pathways in Th2-low disease remains an important goal. Further interrogation of our previously described microarray dataset revealed upregulation of gene expression for carcinoembryonic Ag cell adhesion molecule (CEACAM) family members in the bronchi of patients with severe asthma. Our aim was therefore to explore the distribution and cellular localization of CEACAM6 using immunohistochemistry on bronchial biopsy tissue obtained from patients with mild-to-severe asthma and healthy control subjects. Human bronchial epithelial cells were used to investigate cytokine and corticosteroid in vitro regulation of CEACAM6 gene expression. CEACAM6 protein expression in bronchial biopsies was increased in airway epithelial cells and lamina propria inflammatory cells in severe asthma compared with healthy control subjects. CEACAM6 in the lamina propria was localized to neutrophils predominantly. Neutrophil density in the bronchial mucosa was similar across health and the spectrum of asthma severity, but the percentage of neutrophils expressing CEACAM6 was significantly increased in severe asthma, suggesting the presence of an altered neutrophil phenotype. CEACAM6 gene expression in cultured epithelial cells was upregulated by wounding and neutrophil elastase. In summary, CEACAM6 expression is increased in severe asthma and primarily associated with airway epithelial cells and tissue neutrophils. CEACAM6 may contribute to the pathology of treatment-resistant asthma via neutrophil and airway epithelial cell-dependent pathways.

Expression of human carcinoembryonic antigen-related cell adhesion molecule 6 and alveolar progenitor cells in normal and injured lungs of transgenic mice

Carcinoembryonic antigen-related cell adhesion molecule 6 (CEACAM6) is expressed in the epithelium of various primate tissues, including lung airway and alveoli. In human lung, CEACAM6 is developmentally and hormonally regulated, protects surfactant function, has anti-apoptotic activity and is dysregulated in cancers. We hypothesized that alveolar CEACAM6 expression increases in lung injury and promotes cell proliferation during repair. Studies were performed in CEABAC transgenic mice-containing human CEACAM genes. The level of CEACAM6 in adult CEABAC lung was comparable to that in human infants; expression occurred in epithelium of airways and of some alveoli but rarely co-localized with markers of type I or type II cells. Ten days after bleomycin instillation, both the number of CEACAM6(+) cells and immunostaining intensity were elevated in injured lung areas, and there was increased co-localization with type I and II cell markers. To specifically address type II cells, we crossed CEABAC mice with animals expressing EGFP driven by the SP-C promoter. After bleomycin injury, partially flattened, elongated epithelial cells were observed that expressed type I cell markers and were primarily either EGFP(+) or CEACAM6(+). In cell cycle studies, mitosis was greater in CEACAM6(+) non-type II cells versus CEACAM6(+)/EGFP(+) cells. CEACAM6 epithelial expression was also increased after hyperoxic exposure and LPS instillation, suggesting a generalized response to acute lung injuries. We conclude that CEACAM6 expression is comparable in human lung and the CEABAC mouse. CEACAM6 in this model appears to be a marker of a progenitor cell population that contributes to alveolar epithelial cell replenishment after lung injury.