Cloning and amplification of CD8 + T cells in cerebrospinal fluid of patients with Alzheimer's disease

On January 8, 2020, the research team of mark M Davis and Tony Wyss Coray of Stanford University in the international top academic journal Nature showed that immune cell subsets of adaptive immune system may also play a role in Alzheimer's disease, and immune cell subsets can remember and respond to specific foreign invaders The researchers first analyzed the peripheral blood of healthy people, AD patients and patients with mild cognitive impairment (MCI) by mass spectrometry and cluster their immune cells, and found that CD3 + CD8 + CD27 in AD and MCI- The number of t-effect memory CD45RA + cells (temra, cluster 63) was more than that of healthy people (Fig.1) Temra cells have previously been thought to be involved in immune memory, releasing inflammatory and cytotoxic (cell death promoting) molecules So the question is, can the presence of temra cells be used to predict the state of ad disease? Based on the results of mass spectrometry flow cytometry and machine learning model analysis, the researchers found that the accuracy of temra cells, together with nine other immune cell populations, to distinguish samples from healthy people and patients with Alzheimer's disease (MCI) was as high as 80% (Fig.2) Interestingly, the functional study of temra cells in another group of Alzheimer's patients showed that the level of temra cells in peripheral blood was negatively correlated with cognitive level, and positively correlated with central memory T cells (TCM) and effective memory T cells (TEM) (fig.3a) In addition, inflammatory molecules can stimulate CD8 + cells of MCI and AD patients to secrete more IFN - γ (fig.3b) than that of healthy people, which further proves that T cells of AD patients and MCI patients have stronger effect than that of healthy people Is this cell subset also present in CSF of AD patients? The researchers studied the problem in depth by immunohistochemistry It was found that CD8 + cells existed in the amyloid plaque dense tissue and the perivascular space around the cerebral vessels in AD patients, and the number of CD3 + CD8 + cells in hippocampus of AD patients was significantly higher than that in the control group (Fig.4).