A novel recombinant fusion protein encoding a 20-amino acid residue of the third extracellular (E3) domain of CCR2 neutralizes the biological activity of CCL2.
CCL2 is a key CC chemokine that has been implicated in a variety of inflammatory autoimmune diseases and in tumor progression and it is therefore an important target for therapeutic intervention in these diseases. Soluble receptor-based therapy is a known approach for neutralizing the in vivo functions of soluble mediators. Owing to the complexity of seven-transmembrane G protein-coupled receptors, efforts to generate neutralizing soluble chemokine receptors have so far failed. We developed a strategy that is based on the generation of short recombinant proteins encoding different segments of a G protein-coupled receptor, and tested the ability of each of them to bind and neutralize its target chemokine. We show that a fusion protein comprised of as few as 20 aa of the third extracellular (E3) domain of the CCL2 receptor, stabilized by the IgG H chain Fc domain (E3-IgG or BL-2030), selectively binds CCL2 and CCL16 and effectively neutralizes their biological activities. More importantly, E3-IgG (BL-2030) could effectively suppress the in vivo biological activity of CCL2, attenuating ongoing experimental autoimmune encephalomyelitis, as well as the development of human prostate tumor in SCID mice.
Izhak
Liat
L
Department of Immunology, Rappaport Family Institute for Research in the Medical Sciences, Haifa, Israel.
Wildbaum
Gizi
G
Zohar
Yaniv
Y
Anunu
Rachel
R
Klapper
Leah
L
Elkeles
Adi
A
Seagal
Jane
J
Yefenof
Eitan
E
Ayalon-Soffer
Michal
M
Karin
Nathan
N
D000818:Animals; D002460:Cell Line; D045744:Cell Line, Tumor; D002464:Cell Migration Inhibition / Q000276:immunology; D049109:Cell Proliferation; D018932:Chemokine CCL2 / Q000037:antagonists & inhibitors* / Q000378:metabolism / Q000502:physiology*; D005260:Female; D006801:Humans; D008297:Male; D051379:Mice; D008807:Mice, Inbred BALB C; D008810:Mice, Inbred C57BL; D016513:Mice, SCID; D011471:Prostatic Neoplasms / Q000276:immunology / Q000628:therapy; D011485:Protein Binding / Q000276:immunology; D017434:Protein Structure, Tertiary; D054390:Receptors, CCR2 / Q000378:metabolism / Q000502:physiology*; D011993:Recombinant Fusion Proteins / Q000138:chemical synthesis / Q000378:metabolism / Q000502:physiology*
C111835:CCL2 protein, human; C515334:CCR2 protein, human; D018932:Chemokine CCL2; D054390:Receptors, CCR2; D011993:Recombinant Fusion Proteins