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Printable Handouts
Navigable Slide Index
- Introduction
- Memory maintenance - quantity and quality
- Memory cell survival?
- Lymphocyte lifespan
- There isn't enough room
- Niches for lymphocyte survival
- Niches for lymphocytes
- How do we know about survival niches?
- Niches and memory experiments
- Niche occupancy in different lymphoid systems
- Factors influencing memory cell survival (1)
- Factors influencing memory cell survival (2)
- Factors influencing memory cell survival (3)
- Attrition of memory populations
- Rescue from homeostatic attrition
- A role for antigen?
- FDC native antigen persistence
- Antigen persistence
- Long-lived serum antibody responses
- Protective immunity is not the same as memory
- Protective immunity vs. memory
- Panum and the Faroe Islands measles outbreak
- What did we learn from Panum?
Topics Covered
- Quantity and quality memory maintenance
- Memory cell survival and homeostasis
- Concept of resource ‘niches’ for survival
- A role for antigen in memory longevity
- Memory and protective immunity
Links
Series:
Categories:
Therapeutic Areas:
Talk Citation
Gray, D. (2020, October 29). Immunological memory 2 [Video file]. In The Biomedical & Life Sciences Collection, Henry Stewart Talks. Retrieved December 5, 2024, from https://doi.org/10.69645/XYUX7904.Export Citation (RIS)
Publication History
Financial Disclosures
- I have no disclosures or conflicts of interest connected to my talk.
Immunological memory 2
Published on October 29, 2020
18 min
Other Talks in the Series: The Immune System - Key Concepts and Questions
Transcript
Please wait while the transcript is being prepared...
0:00
My name is David Gray.
I work at the University of Edinburgh in the School of Biological Sciences.
I'm going to talk to you today about immunological memory.
In the second part of my talk,
I will consider how memory is maintained over long periods of time.
0:19
Using these diagrams, which you'll be familiar with, we can think about,
what's the best way to keep memory for long periods of time?
Remember that memory is the basis of vaccination,
and the whole point of vaccination is that you would be protected from
reinfection or at least the symptoms of
suppresses viral disease second time you're exposed to it,
and that, if it's going to be successful,
needs to be protection over many years,
and that's eminently possible using some of the best vaccines available.
They provide protection over 50-60 years,
that's readily been observed.
Again, looking at these diagrams,
there seemed to be a number of different ways in which you could do that.
You could maintain the frequency for long periods of time,
or you could simply maintain cells that have enhanced function.
As we talked about, it's likely to be, and is,
a mixture of both the quantity and the quality,
the quantity of those memory cells and
the quality of those memory cells that's important.
1:19
Some introductory remarks about cell survival,
one needs to ask the question whether a memory cell is an inherently long-lived cell.
In the immune system, are there inherently long-lived cells?
Or do memory cells require external stimuli for their long-term survival?
1:39
In answering that question,
one has to think about lymphocyte lifespan in general,
and some factors which control that.
For instance, the size of the lymphoid system is controlled within very strict limits.
You see an acute expansion of lymph nodes following infection or following immunization,
but that returns to normal within a few days.
So there is a strong homeostatic control of lymphocyte numbers.
Now that's important obviously,
because in the immune system,
we've constantly got input of new lymphocytes from our primary lymphoid organs,
from the bone marrow in our early life,
from the thymus as well for T cells.
In addition to that,
as we've been talking about,
there is clonal expansion following immunization,
so antigen-driven expansion of populations of lymphocytes.
If we'd maintained all of the cells that are generated during
those clonal expansion and the aura generated from our primary lymphoid organs,
the immune system will just get bigger and bigger and bigger,
and come to dominate our body.
In fact, we have a strong homeostatic regulation imposed upon the immune system.
What that means is that all lymphocytes are under constant selective pressure.