When a person is exposed to an infection, they are often protected from getting the same infection again by immune memory, the part of the immune system capable of remembering infectious agents. However, it is still unclear just how the immune system can fight back so quickly when it encounters an infection it has been previously exposed to through a vaccine or an earlier infection. Now, a study from researchers at the Garvan Institute of Medical Research identifies the existence of a previously unknown micro-organ within the immune system they have named the Subcapsular Proliferative Foci (SPF). The team states the thin, flattened structures, extending over the surface of lymph nodes, are dynamic structures, only appearing on command to fight an infection the animal has previously been exposed to. The opensource study is published in the journal Nature Communications.
Previous studies suggest memory B cells are formed within the lymph nodes and spleen following a primary infection and are known to generate an accelerated and more robust antibody-based immune response in the case of re-infection. However, exactly where and how memory B cells are reactivated to make neutralizing antibodies remains unknown. The current study identifies memory B cells in a subcapsular niche in lymph nodes where, upon reactivation by antigen, they rapidly proliferate and differentiate into antibody-secreting plasma cells in the newly discovered SPF.
The current study uses two-photon microscopy and single-cell RNA sequencing to identify the primary source of the secondary antibody response to identify the seat of B cell memory in a previously unknown structure termed the SPF. Results show memory B cells were clustered at the SPF and were changing into infection-fighting plasma cells, a key step in the fight against infection where plasma cells make antibodies to recognize and fend off foreign bodies and protect against disease.
The lab explains up until now the global medical community has been focussed on making vaccines generating memory B cells. They go on to add the discovery of this new structure suggests the focus needs to be on understanding how those memory B cells are reactivated to make plasma cells so the process can be streamlined.
The team surmises they have identified a new part of the immune system, the SPF, where the immune system remembers past infections and vaccinations to mount a rapid response against an infection the body has seen before. For the future, the researchers state their new discovery is an important step towards understanding how to make better vaccines.
Get Healthinnovations delivered to your inbox:
Michelle Petersen is the founder of Healthinnovations, having worked in the health and science industry for over 21 years, which includes tenure within the NHS and Oxford University. Healthinnovations is a publication that has reported on, influenced, and researched current and future innovations in health for the past decade.
Michelle has been picked up as an expert writer for Informa publisher’s Clinical Trials community, as well as being listed as a blog source by the world’s leading medical journals, including the acclaimed Nature-Springer journal series.
Healthinnovations is currently indexed by the trusted Altmetric and PlumX metrics systems, respectively, as a blog source for published research globally. Healthinnovations is also featured in the world-renowned BioPortfolio, BioPortfolio.com, the life science, pharmaceutical and healthcare portal.
Most recently the Texas A&M University covered The Top 10 Healthinnovations series on their site with distinguished Professor Stephen Maren calling the inclusion of himself and his team on the list a reflection of “the hard work and dedication of my students and trainees”.
Michelle Petersen’s copy was used in the highly successful marketing campaign for the mega-hit film ‘Jumanji: The Next Level, starring Jack Black, Karen Gilian, Kevin Hart and Dwayne ‘The Rock’ Johnson. Michelle Petersen’s copywriting was part of the film’s coverage by the Republic TV network. Republic TV is the most-watched English language TV channel in India since its inception in 2017.
An avid campaigner in the fight against child sex abuse and trafficking, Michelle is a passionate humanist striving for a better quality of life for all humans by helping to provide traction for new technologies and techniques within healthcare.