Serum immunomodulatory factors in gastrointestinal diseases. A 30-50-kD serum fraction in Crohn's disease capable of modulating lymphocyte activation.
We tested the hypothesis that serum factors present in Crohn's disease interfere with the process of lymphocyte activation. The mitogen-induced proliferation and the expression of early activation antigens by normal lymphocytes cultured in the presence of either Crohn's disease sera or sera from different controls were evaluated. The mitogen-induced proliferation was significantly impaired in the presence of Crohn's disease sera. These sera markedly inhibited the mitogen-induced interleukin-2 receptor (IL-2R) expression (48% inhibition), while the effect of sera on the expression of the transferrin receptor and the 4F2 antigen was much less pronounced. Diafiltration experiments showed that the inhibitory effect was confined to a 30-50-kD serum fraction. Such a serum property was not related to the patients' disease activity and disappeared after surgical removal of the affected bowel. The capability of inhibiting the mitogen-induced IL-2R expression was not restricted to Crohn's disease and was observed with sera from other inflammatory and neoplastic gastrointestinal disorders. This study indicates that a marked inhibition of the IL-2R is a mechanism underlying the immunosuppressive property of the serum in Crohn's disease and in other gastrointestinal conditions.
Biancone
L
L
Department of Gastroenterology I, Universita La Sapienza, Rome, Italy.
Boirivant
M
M
Fais
S
S
Ricci
G L
GL
Paganelli
R
R
Pallone
F
F
D000328:Adult; D000943:Antigens, Differentiation / Q000096:biosynthesis; D000954:Antigens, Surface / Q000096:biosynthesis; D003424:Crohn Disease / Q000097:blood / Q000276:immunology*; D005260:Female; D027261:Fusion Regulatory Protein-1; D006801:Humans; D007700:Kinetics; D008213:Lymphocyte Activation / Q000187:drug effects / Q000276:immunology; D008297:Male; D008875:Middle Aged; D010835:Phytohemagglutinins / Q000494:pharmacology; D015375:Receptors, Interleukin-2 / Q000096:biosynthesis; D011990:Receptors, Transferrin / Q000096:biosynthesis; D013491:Suppressor Factors, Immunologic / Q000097:blood*
D000943:Antigens, Differentiation; D000954:Antigens, Surface; D027261:Fusion Regulatory Protein-1; D010835:Phytohemagglutinins; D015375:Receptors, Interleukin-2; D011990:Receptors, Transferrin; D013491:Suppressor Factors, Immunologic