Mesothelium: what is it, features and associated diseases

Researchers, with current knowledge, have managed to estimate that the human body is home to around 30 trillion cells. Without a doubt, each tissue has its peculiarities and, for example, 84% of this cell volume in our species corresponds to red blood cells, which carry oxygen in the blood. Yes, strange as it sounds, many experts consider blood to be a type of connective tissue that is fluid in nature.

Humans are 50% protein because they make up half of our dry tissues and, as you can imagine, the biological system that makes us up cannot be designed without tissue as a basic level of organization at the core. – beyond the cell. Lula. It’s all about perspective, but in short, without tissue organization, we are nothing.

This whole introduction emphasizes the diversity and importance of the tissues in our body. We all know what a nerve or muscle tissue is because of its clear functionality, however, What comes to your mind if we call you the term “mesothelium”? If the answer is nothing, don’t worry, because here you will find all the information you need to know about it.

    What is Mesothelium

    Let’s start directly. From a physiological point of view, the mesothelium is defined as a type of simple scaly epithelium resting on a basal lamina supported by connective tissue. We dissect each of these terms:

    • Epithelium: tissue made up of closely related cells (flat or prismatic), which covers the outer surface of the body and some organs.
    • Simple epithelium: Going one step further, simple epithelium is one that consists of a single layer of cells in contact by binding complexes.
    • Squamous epithelium (stratified): made up of a layer of flattened (squamous) cells on a basement membrane.

    It makes things clearer, right? We are talking about a very simple type of tissue: a single layer of flattened cells. To locate this curious tissue, it should be noted that it is the outermost layer of the peritoneumBut what is it?

    The peritoneum is the serous layer that covers the inside of the abdominal cavity, that is, the “empty space” in which all of our organs are housed. This is made up of two layers, and between them there is a space (peritoneal cavity) that holds about 50 milliliters of lubricating fluid that allows them to slide together. It is the most extensive serous membrane in the body because, in addition to having the peritoneal cavity, it also houses our intestines. It is estimated that, for this reason, it occupies 40-50% of the total surface of the skin.

    The mesothelial cell

    We have already described the general shape of the mesothelium and its location, which is why it is enough to pay particular attention to its basic functional unit, the mesothelial cell, to complete the panorama of this unique tissue. Let’s do this.

    The mesothelial cell is of the flat epithelial type, of mesenchymal origin (lax conjunctiva of embryonic origin) which covers the serous cavities. These cells form a monolayer having the appearance of a polygonal mosaic in which certain microvilli emerge. Proteins and serous fluids trapped between these microvilli provide a low friction surface, which is an excellent contact area between organs. In contrast, these cells are based on a basement membrane (MB) which offers little resistance to the passage of molecules of less than 30,000 daltons.

    Finally, it should be noted that mesothelial cells are very reactive. This means that they change their appearance easily. For example, when at rest, they are observed in well-organized groups of different volume, with a high nucleus: cytoplasm ratio. On the other hand, as they are activated, their size increases, forming irregular cytoplasmic protrusions and greater vacuolation. Unfortunately, this plasticity can be a problem: it’s time to talk about cancer in the next few lines.

    Functions of the mesothelium

    The main purpose of mesothelial cells (and therefore of the mesothelium) is create a layer of lubricating fluid that is released between the coating layers, Producing a slippery, non-stick surface.

    In addition to this, the mesothelium also assumes transport and movement of particles and cells between cavitiesThese include leukocytes, involved in the immune response as inflammatory mediators. In short, it is a “passage” tissue that allows the sliding between the organs and the transport of various substances and cell bodies essential to the physiological well-being of the organism.

      Mesothelioma, a cancer of mesothelioma

      Like virtually all cells in the body that grow and replace themselves, mesothelium is a potential candidate for cancer events. After all, cancer is nothing more than a mutation in a cell that causes it to divide uncontrollably and does not respond to normal periods of apoptosis (cell death), leading to cancer, ”a malignant tumor feared. .

      Mesothelioma can be divided into several categories depending on the affected site. Among them we find the following.

      1. Pleural mesothelioma

      It affects the tissues surrounding the lungs i.e. it develops in the chest cavity. It can cause chest pain, painful cough, difficulty breathing, unusual lumps under the skin of the chest, and weight loss with no apparent cause, among others.

      2. Peritoneal mesothelioma

      As indicated by his name, affects the tissues of the abdomen (peritoneum). It causes abdominal swelling, abdominal pain, nausea, and weight loss with no apparent cause. Unfortunately, both types of mesothelioma are extremely aggressive and lead to a significant case fatality rate.

      3. Other types of mesothelioma

      There are more types of mesothelioma depending on the tissue they affect because, for example, pericardial mesothelioma grows in the tissues surrounding the heart, causing breathing problems and tightness. On the other hand, mesothelioma of the tunica vagina affects the lining of the testes. fundamentally any mesothelial wall is susceptible to the appearance of a malignant tumorAlthough not all mesothelial tumors automatically result in cancer.

      Distribution and epidemiology of mesothelioma

      Mesothelioma occurs in approximately 1 to 2 patients for every million people per year. Unfortunately, people who work in the construction industry (especially if they come in contact with asbestos) are more likely to have it up to 40 times more. This aggressive type of cancer kills around 5,000 people per year in Europe and 3,000 in the United States per year.

      The typical mesothelioma patient is a 60-year-old man who has worked in this type of industry for at least 30 years.. It’s shocking to learn that, in most cases, it typically takes 20 to 40 years after exposure to asbestos (in vinyls, cars, and building materials) for cancer to develop.

      For this reason, the World Health Organization (WHO) has recommended all countries around the world to stop using this material in construction. Unfortunately, in 2010, this organization estimated that despite global bans, 125 million people around the world remain in close contact with asbestos. In addition to mesothelioma, this material also causes asbestosis (scar damage in the lungs and pleura) and lung cancer., In addition to possible metastases derived from these types of malignant tumors.


      As you can see, the mesothelium is a very simple structure that has a lot of secrets to unravel. To understand us (and in a more familiar final note), we can say that it is a simple layer that allows the sliding between organs and the transport of substances, from proteins to immune organisms. specialized, as well as many other cell types.

      Mesothelioma is a very rare type of malignancy in the general population but unfortunately occurs almost exclusively in people who have worked in work in contact with asbestos. If you have a history of work / physical labor and notice strange bumps on a soft part of your body, abdominal swelling, and continuous coughing, see your doctor promptly.

      Bibliographical references:

      • Mesothelial cells, University of Navarre clinic (CUN). Accessed December 26
      • Mesothelial cells … The great challenge of cytology, Collected on December 26 from
      • Martín, LB, Pereira, PP, Llista, FS and Castañón, LB (2013). Mesothelioma of the tunica vagina. Spanish Urology Archives, 66 (4), 384-388.
      • Mesothelioma, Retrieved December 26 from
      • Mesothelioma, Collected December 26 at,exposici%C3%B3n%20prolongada%20a%20los% 20asbestos.
      • WHO warns of asbestos exposure of 125 million people, UN News. Retrieved December 26, from
      • Forner, FR (2015). Diagnosis and treatment of malignant pleural mesothelioma. Archives of bronchopneumology, 51 (4), 177-184.

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