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Prior vaccination promotes early activation of memory T cells and enhances immune responses during SARS-CoV-2 breakthrough infection

Journal Article Review about how Prior vaccination enhances immune responses

By John L Elliott MS

This journal article explores why getting vaccinated decreases mortality.   It is a study about how prior vaccinations enhances immune responses.  Here is the opening sentence of the Abstract.  “Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection of vaccinated individuals is increasingly common but rarely results in severe disease, likely due to the enhanced potency and accelerated kinetics of memory immune responses”.  So lets decode this from science journal talk.

What it means is the more vaccinations you get the less likely you are to have severe reactions from being exposed.  From personal experience, I have seen this with my tetanus shots and when I was re vaccinated with Smallpox in 1954, 1968 and 1974.

What this study does is prove this hypothesis for SARS-CoV-2 variants with evidence based medicine and statistics.

Now for the Goodies

The Method used

Measurement of Memory B and T cells are capable of robust recall responses following booster vaccination, supporting the functional nature of mRNA vaccine-induced immune memory are measured.   These cells were measured by Flow Cytometry and 46 people were used in the study.  (That means they had statistical significant group).

Flow Cytometry was used to measure

Samples were acquired on a BD Symphony A5 instrument using FACSDiva software v8.0.1. Standardized SPHERO rainbow beads (Spherotech) were used to track and adjust photomultiplier tubes over time. UltraComp eBeads (Thermo Fisher Scientific) were used for compensation. Up to 5 × 106 cells were acquired per sample. Data were analyzed using FlowJo v10 (BD Bioscience) or OMIQ.


In a nice Graph

figure 6




Prior vaccination promoted a coordinated spike-specific recall response during SARS-CoV-2 infection marked by increases in neutralizing antibodies, activated memory B cells and activated CD8 T cells compared to unvaccinated individuals.

Link to article



The researchers