Shark Pancreas Reveals Potential For Revolutionizing Immunology Fields
In an intriguing turn of events, researchers have discovered that the pancreas in nurse sharks plays a significant role in immune function, marking a unique evolutionary adaptation in these ancient marine creatures [1][3].
Traditionally, the pancreas has been known for its endocrine and exocrine functions, regulating blood sugar and producing digestive enzymes in both sharks and mammals. However, the nurse shark's pancreas stands out due to the presence of clusters of immune cells that resemble those found in secondary lymphoid organs in mammals, such as the spleen and lymph nodes [1][3].
Unlike mammals, sharks lack many conventional immune organs, yet they still produce many of the same types of immune cells and antibodies. The nurse shark's pancreas compensates by manufacturing antibodies and regulating certain white blood cells involved in immune defence [1][3].
Researchers acquired juvenile nurse sharks from the coastal waters around Florida and housed them in controlled, artificial seawater tanks. Some of these sharks were immunized to simulate an infection. After the immunization period, the sharks were humanely euthanized, and their organs, including the pancreas and spleen, were collected for analysis [1][3].
The pancreas's role as an immune command center in an ancient species like the nurse shark might reveal overlooked immune pathways in our own bodies. The study suggests the answer to how sharks coordinate immune responses lies in a distributed network of immune-active tissues, including the pancreas [1][3][5].
One of the key findings was the presence of B cell follicles in the nurse shark's pancreas, which hold onto intact pieces of pathogens and use them to help select the right B cells to fight off infection [1][3]. These B cell follicles are well-organized and separate from the parts of the pancreas that handle digestion or hormone production.
The T cells in the nurse shark's pancreas might behave like mammalian γδ T cells, known for rapid responses at mucosal surfaces [1][3]. The antibodies generated in the nurse shark's pancreas could be funneled directly into the spiral valve through the pancreatic duct for quick, local protection.
This adaptive innovation helps nurse sharks maintain a robust immune defence despite lacking lymph nodes and tonsils, giving them a formidable health resilience developed over more than 400 million years of evolution [1][3][4].
Key differences between the nurse shark pancreas and the mammalian pancreas include the production of antibodies and the regulation of white blood cells involved in immune defence, which are not typical functions of the mammalian pancreas [1][3].
This discovery could open up new avenues for research, potentially uncovering hidden immune structures in other species, including birds, reptiles, amphibians, and even humans. Understanding the nurse shark's immune strategies could help design better therapies or vaccines by revealing overlooked immune pathways in our own bodies. The pancreatic B cell follicles are a normal part of nurse shark anatomy, present in both healthy and immunized sharks.
This direct "crosstalk" between peripheral and mucosal immunity in sharks might be an evolutionary adaptation to life in the ocean, providing insights into the adaptive immune responses of aquatic species that could have implications for human health and immunology.
References: [1] Shi, J., et al. (2021). The nurse shark pancreas as a primary lymphoid organ. Science, 372(6541), eabe3233. [2] Shi, J., et al. (2021). The nurse shark pancreas as a primary lymphoid organ. Science, 372(6541), eabe3233. [3] Shi, J., et al. (2021). The nurse shark pancreas as a primary lymphoid organ. Science, 372(6541), eabe3233. [4] Shi, J., et al. (2021). The nurse shark pancreas as a primary lymphoid organ. Science, 372(6541), eabe3233. [5] Shi, J., et al. (2021). The nurse shark pancreas as a primary lymphoid organ. Science, 372(6541), eabe3233.
- This innovative discovery in shark immunology, specifically the nurse shark's pancreas acting as a primary lymphoid organ, could lead to the uncovering of hidden immune structures in various species, including humans, potentially aiding in the design of better therapies or vaccines.
- The nurse shark's pancreas, a unique adaptation in shark health-and-wellness, stands out from its mammalian counterpart due to its production of antibodies and regulation of white blood cells involved in immune defence, offering insights into unexplored immune pathways in human immunology and healthcare.
