Methods of diagnosis or of quantitation of fibrosis comprising conducting an immunoassay to measure neo-epitope containing protein fragments naturally present in a bioflui sample, and associating an elevation of said measure in said patient above a normal level with the presence or extent of fibrosis. The immunoassay is conducted by a method comprising:
contacting protein fragments naturally present in said sample with an immunological binding partner reactive with a neo-epitope formed by cleavage of a protein by a proteinase and
measuring the extent of binding of peptide fragments to said immunological binding partner to measure therein protein fragments comprising said neo-epitope, and wherein said protein is collagen type III, collagen type I, collagen type IV,
collagen type V, or collagen type VI, elastin, biglycan, decorin, lumican, versican, perlecan, neurocan, brevican, fibromodulin, serglycin, syndecan, betaglycan, vimentin, or C-reactive protein.