Many can envision how the cells of the immune system (body’s defense mechanisms) communicate and release factors, such as antibodies, to protect us from invading organisms. These biological and chemical mechanisms used by immune system cells are studied extensively. New data shows that physical forces are involved in the processes used against pathogenic (disease-causing) organisms by immune cells such as cytotoxic T cells, a class of T cells that destroys invading organisms.
Bone marrow stem cells, the source of immune cells, lose their mojo over time. Can research help them go an extra mile?
Ah, the aging process. Over time, cells lose the spring in their step, and tissues and organs aren't maintained the way we like them to be. The same holds true for our bone marrow stem cells. Long-lived cells of this type decline in their ability to generate the cell types that derive from them, including immune cells, which raises the risk of infections for elderly patients.
The 1976 convention of the American Legion in Philadelphia turned out to be an ill-fated event: Around 200 attendees contracted pneumonia, and about 30 eventually succumbed to the disease, which was caused by a hitherto unknown but quickly famed bacterium: Legionella pneumophila. This microbe evades the immune response by a particularly sneaky mechanism. It lets itself be eaten by the host’s macrophages, and instead of perishing, like regular pathogens, it makes itself a cozy home within those immune cells. It does this by preventing the fusion of the phagosome, where the bacteria reside, with the lysosome, which carries the killer enzymes that usually tackle the invading microbes, inside the macrophages. Instead, the bacteria continue to replicate happily inside the immune cells until these burst, releasing thousands of new bacteria that can hunt for new macrophages, thereby spreading all over the body. The disease is often deadly, especially when antibiotic treatment is delayed.
A diet high in fish intake, providing abundant long chain omega-3 fatty acids, may reduce mortality after breast cancer.
Leukemia cells possess mitochondrial and metabolic alterations, which may be an Achilles' heel to a compound from avocados.