How Were Antibodies Discovered?
July 24, 2026Core Framework & Diagram The Discovery of T Cells and B Cells
July 24, 2026
The Discovery of T Cells and B Cells
Scientists spent seventy years figuring out that the immune system has two completely different types of lymphocytes
By the Editors 1-min read
Today, T cells and B cells are the most foundational concepts in immunology textbooks — even middle school students have heard of 'immune cells.'
But until the 1960s, scientists hadn't realized that 'lymphocytes' were actually two completely different things — one responsible for directly killing enemies (T cells), one responsible for manufacturing antibody weapons (B cells).
Before that, what was the thymus? The medical consensus: a vestigial organ, like the appendix, a useless leftover from evolution. A hundred years of textbooks said so.
What shattered this understanding was a 26-year-old PhD student — armed with a scalpel, a batch of newborn mice, and an experiment designed originally not for studying immunity at all.
KEY TAKEAWAYS
01
The thymus was considered a vestigial organ for a hundred years until Jacques Miller's 1961 mouse experiment completely overturned this — he was only trying to study leukemia virus. His first reaction upon seeing unexpected results was 'did I do something wrong?' He repeated the experiment anyway.
02
The discovery of B cells started from a batch of chickens 'sold to the wrong experiment': Bruce Glick removed chickens' bursa of Fabricius; those chickens were incidentally used in an antibody experiment, accidentally revealing the bursa's essential role in antibody production.
03
The letter 'B' in B cells has a double coincidence: Bursa of Fabricius (development site in birds) and Bone marrow (development site in humans) — both begin with B, a completely accidental coincidence in scientific history that made the name work universally.
04
The 'nude mouse' (no-thymus mutant mouse) went from a defect to becoming one of the most important animal models in decades of global cancer research — almost every cancer treatment tested in animals passed through nude mice.
05
Miller said in his later years that the most important discoveries, when they first appear, make you doubt your methods rather than immediately recognizing how important they are. 'Something's not right here' sometimes is the entrance to major discoveries.
Art 156
The Accidental Discovery of NK Cells
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Art 157
The Birth of 'Immune Surveillance Theory'
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