Immune system cells involved with antigens outside of cells evolve from the yolk

Resident tissue macrophage
https://www.ncbi.nlm.nih.gov/pmc/articles/PMC5675852/
https://www.ncbi.nlm.nih.gov/pubmed/26992565

langerhans
https://link.springer.com/chapter/10.1007/978-1-4757-9966-8_76
https://www.ncbi.nlm.nih.gov/pubmed/22565823

M cells and GH
https://joe.bioscientifica.com/view/journals/joe/147/3/joe_147_3_002.xml

B1 and B2 cells
https://www.sciencedaily.com/releases/2019/02/190215082333.htm