Written By: Camryn Keeble

Mesothelial Cells

Mesothelial cells are specialized cells that form a thin tissue layer that lines the inside of the chest cavity, abdominal cavity, and covers the surface of many organs in the body. Mesothelial cells produce a fluid that lubricates the area between the organs to allow them to easily move within the body without causing friction.

Karen Ritter, RN BSN

Medically Reviewed By

Karen Ritter, RN BSN

Registered Nurse

Karen Ritter, RN BSN

Medically Reviewed By

Karen Ritter, RN BSN

Registered Nurse


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Importance of Mesothelial Cells

Mesothelial cells play an important role in maintaining the integrity and function of various organs within the body. These cells line the inside surfaces of the body cavities, such as the chest, abdomen, and heart.

Function of Mesothelial Cells

Mesothelial cells have important functions, including:

  • Lubricate and protect: Mesothelial cells produce a lubricating fluid that reduces friction between internal organs and helps prevent damage from external pressure or impact.
  • Immune response: Mesothelial cells assist the immune system by helping to detect and respond to foreign invaders such as bacteria, viruses, and cancer.
  • Regeneration: Mesothelial cells help regenerate and repair damaged tissue. This is crucial for maintaining the function of the organs in the chest and abdomen.
  • Structural support: Mesothelial cells form a barrier between organs and the structures of the body cavities, helping to maintain structural integrity.

Types of Mesothelial Cells

Mesothelial cells are a form of epithelial cell. These cells are found in the linings of the pleura (lung lining), peritoneum (abdominal lining), and pericardium (heart lining).

Pleural Mesothelial Cells

Pleural mesothelial cells line the surface of the pleura, which is the thin tissue that covers the lungs and lines the inside of the chest cavity. These cells help provide a protective barrier and cushion between the lungs and the chest wall.

Peritoneal Mesothelial Cells

Peritoneal mesothelial cells line the inside surface of the abdominal cavity and cover many of the organs in the abdomen. These cells help lubricate around the abdominal organs so they can move smoothly against each other and the inside of the abdominal wall. They also work with the immune system to help fight off infection and other diseases. 

Pericardial Mesothelial Cells

Pericardial mesothelial cells line the pericardial cavity, or the space around the heart. These cells provide lubrication, protection and support to the heart and surrounding tissues. 

Abnormal Mesothelial Cells

Exposure to asbestos, inflammation, or infection can cause abnormalities and changes in the mesothelial cells. There are different types of abnormal mesothelial cells including reactive, atypical, and malignant cells – each can have a significant impact.

Reactive Mesothelial Cells

Reactive mesothelial cells have changes in response to injury, inflammation, or infection. These can be a normal response, however they can also be in response to different diseases, such as mesothelioma or other forms of cancers.  

Atypical Mesothelial Cells

Atypical mesothelial cells have changes in their size, shape, and function.. The presence of atypical mesothelial cells can be a sign of an underlying disease or condition, including mesothelioma or other cancers. Not all atypical mesothelial cells are indicative of cancer, some changes may be due to benign conditions or reactive changes. 

Malignant Mesothelial Cells

Malignant mesothelial cells have undergone changes that have made them cancerous. These cells can form tumors in the mesothelial lining of the lungs, abdomen, or other organs. Malignant mesothelial cells are most commonly associated with mesothelioma, a rare and aggressive cancer that is caused by asbestos exposure. When malignant mesothelial cells are found, further testing is necessary to determine the extent and stage of the cancer.

Causes of Abnormal Mesothelial Cells

  • Asbestos exposure – The most common cause of abnormal mesothelial cells is exposure to asbestos. When asbestos fibers are inhaled or ingested, they can become lodged in the lining of the chest or abdomen and cause inflammation and scarring, which can lead to the formation of abnormal mesothelial cells. 
  • InflammationChronic inflammation can lead to tissue scarring and fibrosis, which can alter the normal structure and function of the mesothelial cells and promote abnormal cell growth.
  • Infection – Certain types of infections, such as tuberculosis and viral infections, can cause inflammation and damage to the mesothelial cells.
  • Trauma – Trauma to the chest or abdomen can cause damage to the mesothelial cells, leading to abnormal cell growth.
  • RadiationRadiation therapy used to treat cancer can damage the mesothelial cells, leading to abnormal cell growth.
  • Cancer – Mesothelioma is a rare cancer that forms in the lining of the chest and abdomen, affecting the mesothelial cells. Abnormal mesothelial cells can be an early sign of this cancer.

Not all abnormal mesothelial cells are cancerous, a proper diagnosis is needed to determine the underlying cause. If abnormal mesothelial cells are found in a fluid or tissue biopsy, further testing may be needed to determine the underlying cause. 

Sources & Author

  1. 3 Fascinating Facts About Mesothelial Cells. Cancer Support Community. Retrieved from: https://www.cancersupportcommunity.org/blog/3-fascinating-facts-about-mesothelial-cells-and-what-you-need-know-about-mesothelioma#:~:text=Mesothelial%20cells%20surround%20the%20body’s,of%20tissue%20called%20the%20mesothelium. Accessed 4/19/2023.The Panorama of Different Faces of Mesothelial Cells. National Library of Medicine – CytoJournal. Retrieved from: https://www.ncbi.nlm.nih.gov/pmc/articles/PMC8813612/. Accessed 4/20/2023.
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About the Writer, Camryn Keeble

Camryn Keeble is the senior content writer and editor for Mesothelioma Guide. She creates informative content to educate mesothelioma patients and their loved ones on news, treatments and more. She also works diligently to raise awareness of the dangers of asbestos exposure and the effects of mesothelioma.