Not exactly ccr5 related, we will see, but cd4 cel

Not exactly ccr5 related, we will see, but cd4 cell connected, which we know of the HIV connection there. Very interesting with the subset of cd4 cells that gain cd8 capability (cytotoxic),called cd4 CTL. Apparently, people that make it past 110 have an abnormally large number of this type of CD4 cells. Adding that ability to do both seems to help increase fight against infection and cancer.


https://www.sciencedaily.com/releases/2019/11...101845.htm

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. CD4-positive cells generally work by generating cytokines, while CD8-positive cells are cytotoxic, and it may be that the combination of these two features allows these individuals to be especially healthy.

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Scientists from the RIKEN Center for Integrative Medical Science (IMS) and Keio University School of Medicine in Japan have used single-cell RNA analysis to find that supercentenarians -- meaning people over the age of 110 -- have an excess of a type of immune cell called cytotoxic CD4 T-cells. Supercentenarians are somewhat of a unique group of people. First, they are extremely rare. For example, in Japan in 2015 there were more than 61,000 people over the age of 100, but just 146 over the age of 110. And studies have found that these individuals were relatively immune to illnesses such as infections and cancer during their whole lifetimes. This led to the idea that it might be that they have a particularly strong immune system, and the researchers set out to find out what might explain this.

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paper,
https://www.pnas.org/content/early/2019/11/11/1907883116

Single-cell transcriptomics reveals expansion of cytotoxic CD4 T cells in supercentenarians

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Furthermore, single-cell T cell receptor sequencing of 2 supercentenarians revealed that CD4 CTLs had accumulated through massive clonal expansion, with the most frequent clonotypes accounting for 15 to 35% of the entire CD4 T cell population. The CD4 CTLs exhibited substantial heterogeneity in their degree of cytotoxicity as well as a nearly identical transcriptome to that of CD8 CTLs. This indicates that CD4 CTLs utilize the transcriptional program of the CD8 lineage while retaining CD4 expression. Indeed, CD4 CTLs extracted from supercentenarians produced IFN-γ and TNF-α upon ex vivo stimulation. Our study reveals that supercentenarians have unique characteristics in their circulating lymphocytes, which may represent an essential adaptation to achieve exceptional longevity by sustaining immune responses to infections and diseases.

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