Sera were obtained from patients with or without fibrosis and then assayed in triplicate for SP-IR using ELISA.

(A) MPD, with fibrosis (●, other MPD, n = 19; ▾, IMF, n = 15) or without BM fibrosis (★, n = 19). Non-MPD with fibrosis (▴, n = 10) or without fibrosis (▪, n = 27). NC, healthy controls (n = 30). (B) Grouped data from patients, shown in panel A: BM fibrosis (3-4+ reticulin fibers) versus no fibrosis. Results are expressed as mean ± SD. *P < .01 versus no fibrosis.