Immunity system complexity: development in the fetus (Introduction)

by David Turell , Friday, November 22, 2024, 21:54 (4 hours, 57 minutes ago) @ David Turell

Latest studies:

https://www.sciencedaily.com/releases/2024/11/241120121641.htm

"The immune system protects the body from infections and cancer with the help of a diverse array of T cells, a type of white blood cell. T cells must first be trained to recognise threats without attacking the body's own healthy cells. The thymus, a small organ behind the breastbone, is where this crucial T cell training occurs.

"When the thymus malfunctions, it can result in weakened immunity or autoimmune diseases, where the body mistakenly attacks itself, leading to conditions such as type 1 diabetes or rheumatoid arthritis.

"Despite its importance, little is known about the early development of the thymus, as it uniquely functions primarily during infancy and then gradually degenerates over the lifespan2. Studying its early stages could allow us to understand why immunity wanes with age, leaving older adults vulnerable to infection and less responsive to vaccines.

"In this new study, researchers from the Wellcome Sanger Institute and their collaborators tracked thymus and T cell development in samples ranging from eleven weeks post-conception to three years old4 using single cell sequencing and advanced spatial mapping techniques.

"They discovered that the organ's basic structure and function is established as early as twelve weeks post-conception, suggesting that early pregnancy factors may have a more profound impact on lifelong immune function than previously recognised.

"The team uncovered key differences in the development of various T cells types5 -- some that help orchestrate immune responses by directing other immune cells and others that directly attack infected or cancerous cells. This understanding could inform new T cell engineering therapies that selectively boost immunity for cancer treatments or suppress it for autoimmune conditions and transplants.

"The researchers also discovered locations of progenitor cells that give rise to important supporting cells in the thymus which also mimic the body's own environment so that T cells would not react to self. This could help researchers in the future to create an artificial thymus for regenerative immune therapies for older adults or people with compromised immune systems.

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"OrganAxis lets us integrate different spatial datasets to uncover hidden properties that go unnoticed when viewed individually. Using key structures as reference points, much like a hiker uses landmarks to navigate, we now see how structures are formed early on, enabling us to track T cell training over time."

"Dr Veronika Kedlian, co-first author of the study formerly at the Wellcome Sanger Institute, and now based at the Cambridge Stem Cell Institute, University of Cambridge, said: "Our atlas of healthy thymus development could lead to new strategies for boosting immunity, particularly in older adults or those with thymus deficiencies."

Comment: it is amazing to see immune preparations in the fetus for anticipated future infections. This can't evolve in an evolutionary process conducted solely by chance mutations and is strong evidence for design.