They make human tears in the laboratory

The Organoid group at the Hubrecht Institute has managed to manufacture tears in the laboratory. US scientists have developed the first laboratory organ model of the human conjunctiva, organoids that mimic the function of real human conjunctiva, a tissue involved in tear production. Using their new model, the researchers have discovered a new type of cell in this tissue: hair cells. Such hair cells increase in number under allergy-like conditions and therefore likely play a role in allergic reactions. The researchers believe that this organoid model can now be used to test drugs for various diseases that affect the conjunctiva. The study is published in the journal ‘Cell Stem Cell’. Related News standard Yes Artificial ‘brains’ are created with human cells that learn to recognize voices Patricia Biosca Manufactured from organoids connected to an electronic system, these hybrid systems could mark the future of neural networks and artificial intelligence The tears that generating eyes protect us against injuries and infections. The conjunctiva, a tissue that covers the white part of the eye and the inside of the eyelids, is partially responsible for the production of these tears. It participates in the production of tears by releasing mucus. This mucus allows tears to adhere to the ocular surface and defend it against pathogens. There are many diseases and disorders that affect the conjunctiva, such as dry eye disease, cancer, allergies and infections. In severe cases, dysfunction of this tissue can lead to blindness. Until now, there was no good model of the human conjunctiva, which limited research into its role in disease and health. As a result, treatment options for diseases affecting the conjunctiva are limited. To learn more about the composition and function of the conjunctiva, this group set out to develop the first human model of this type of tissue. They used cells from a real human conjunctiva and grew them into three-dimensional structures in a laboratory dish. Such miniature structures are called organoids and function like real human conjunctiva. “Once we had these functional organoids, we wanted to know how the conjunctiva is involved in tear production,” explains Marie Bannier-Hélaouët, principal investigator of the project. “We found that the conjunctiva produces antimicrobial components and therefore contributes to tear production in more ways than simply producing mucus.” Related News standard Yes Closer to artificial life: they create functional cells with more than half of their synthetic DNA José Manuel Nieves For the first time, scientists have managed to ‘manufacture’ a yeast cell with more than half of their created DNA artificially in the laboratory With the aim of imitating allergic diseases, they altered the conditions of the conjunctiva in the laboratory. “The organoids began to produce completely different tears: there was more mucus but also more antimicrobial components,” says Bannier-Hélaouët. Under these conditions, they found a new type of cell in the organoids: hair cells. “Similar cells have been discovered in other tissues, but not in the human conjunctiva.” Under allergy-like conditions, the number of mucus-producing cells increases Marie Bannier-Hélaouët, copyright: Hubrecht Institute. Hair cells became more abundant under the allergy-like conditions, suggesting they play a role in the eye’s reaction to allergies. In addition, the new organoid model opens the door to research on diseases that affect the conjunctiva. “We can use our model to test medications for allergies or dry eye diseases, for example,” says Bannier-Hélaouët. In the long term, it might even be possible to make replacement conjunctivae for people with eye burns, cancers or even genetic disorders.