If you take a biopsy of an inflamed part of the intestine in a person with ulcerative colitis, you can stain the cells in that sample, look at them under a micr

If you take a biopsy of an inflamed part of the intestine in a person with ulcerative colitis, you can stain the cells in that sample, look at them under a microscope, and see a lot of gunk collecting around the nucleus that you don't see in the same type of cell in a healthy person. (This gunk is called p-ANCA, if you're interested in looking it up.) If you take that gunk and analyze it with x-ray crystallography, you find that the compound in this gunk has the structure of an antibody. I'd love to hear the intersection of Occam's razor and how you explain these findings with a theory other than autoimmune disease.