Squadre dell'Università della California – Gli angeli (UCLA) Scienze della salute , Stati Uniti d'America, for the first time were able to turn
human stem cells
into sensory interneurons, responsabile del senso del tatto. The technique, published January 11, 2018 in Stem Cell Reports, could be become the basis of terapia con cellule staminali, which will help restore sensitivity in paralyzed patients.
Projecting The Future
Sensory interneurons, a class of neurons in the spinal cord, are responsible for the transmission of a signal that receives from the external and internal environment of the body sensitive neurons. Violation of this function in paralyzed people leads to a lack of tactile sensations, as well as insensitivity to pain, which can be the cause of burns and other domestic injuries.
“The field has for a long time focused on making people walk again,” – said Samantha Butler, the study’s senior author. “‘Making people feel again doesn’t have quite the same ring. But to walk, devi essere in grado di sentire e sentire il tuo corpo nello spazio; i due processi vanno davvero a braccetto.”
In uno studio, pubblicato a settembre 2017 sulla rivista eLife, Butler e i suoi colleghi hanno determinato come i segnali di una famiglia di proteine chiamate proteine morfogenetiche ossee, o BMP, influenzare lo sviluppo degli interneuroni sensoriali negli embrioni di pollo. Nel nuovo lavoro, gli scienziati applicano i risultati alle cellule staminali umane in laboratorio.
I ricercatori hanno aggiunto una specifica proteina morfogenetica ossea BMP4, as well as a signal molecule that helps regulate the formation of various types of tissues of a growing embryo called retinoic acid, to human embryonic stem cells.
Di conseguenza, the cells differentiated into a mixture of two types of sensory interneurons: dl1, which give people proprioception a sense of where their body is in space, and dl3, allowing to feel a sense of pressure.
The researchers found that an identical mixture of sensory interneurons develops by adding the same signal molecules to induced pluripotent stem cells (iPSC). These cells are created by reprogramming the patient’s own mature cells, come, Per esempio, skin cells.
IP Stem cells
can evolve into any type of body cells, while preserving the genetic code of the person from whom they were obtained. The ability to create sensory interneurons from the patient’s own reprogrammed cells without inhibiting the immune system can be a real breakthrough in cell therapy aimed at restoring sensitivity.
Butler spera che sarà in grado di creare una tecnica per ottenere un tipo di neurone alla volta, che semplificherà la definizione delle funzioni di ciascun tipo di cellula e consentirà l'uso clinico degli interneuroni per iniziare a trattare le persone paralizzate. però, il suo gruppo di ricerca non è ancora riuscito a determinare come fare in modo che le cellule staminali producano cellule interamente dl1 o interamente dl3. Forse, in questo processo è coinvolto un altro percorso del segnale, lei ha notato.
Researchers also have not yet determined the specific ratio of growth factors that stimulate stem cells to differentiate into other types of sensory interneurons.
At this stage of the work, the UCLA group implants the interneurons dl1 and dl3 into the spinal cord of mice to determine whether the cells are integrated into the nervous system and become fully functional. This is an important step in determining the clinical potential of cells.
