28 Feb 2022
Setting it Straight: Viruses, Vaccines and COVID-19: heading on and out to search and destroy
Following an Omicron ‘breakthrough’ infection in a vaccinated individual, the linked processes of clonal expansion and differentiation towards ‘effector’ phase (#91-93) continue in the draining lymph nodes (LNs) for ‘recalled’ memory (vaccine primed) and naïve (unique to Omicron) T cells and B cells. This ‘stimulus phase’ likely ends when the viral antigen-presenting dendritic cells (APDCs) are eliminated by the CD8+ killer T cells. Within days – maybe four to six for the memory sets, seven to ten for the naïve – the progeny plasmablasts (B cells) and ‘activated’ T cells begin exiting the LNs to join the circulating white blood cell (WBC) pool. Departing via the thin-walled efferent lymphatics, the lymph flow carries them to the large lymphatic ducts that discharge into the right or left subclavian vein.