The Myeloid Blood Cell Differentiation-Inducing Protein MGI-2A Is Interleukin-6

• Published in: Blood 1988-12, Vol.72 (6), p.2070-2073
• Main Authors: Shabo, Yosef, Lotem, Joseph, Rubinstein, Menachem, Revel, Michel, Clark, Steven C., Wolf, Stanley F., Kamen, Robert, Sachs, Leo
• Format: Article
• Language: English
• Subjects: Amino Acid Sequence; Analytical, structural and metabolic biochemistry; Animals; Biological and medical sciences; Cell Differentiation - drug effects; Cell Line; Fundamental and applied biological sciences. Psychology; Interleukin-6; Interleukins - pharmacology; Leukemia, Myeloid - pathology; Mice; Molecular Sequence Data; Peptide Fragments - pharmacology; Protein hormones. Growth factors. Cytokines; Proteins; Tumor Cells, Cultured - drug effects; Tumor Cells, Cultured - pathology
• ISSN: 0006-4971; 1528-0020
• DOI: 10.1182/blood.V72.6.2070.2070

The mouse myeloid blood cell differentiation-inducing protein, macrophage and granulocyte inducer, type 2A (MGI-2A), was purified, and the amino acid sequence of a CNBr cleavage peptide (22 residues) was determined. This amino acid sequence is identical to the sequence found in positions 73 to 94 of mouse interleukin-6 (IL-6). Recombinant mouse IL-6 protein induces differentiation of mouse myeloid leukemic cells that are induced to differentiation by MGI-2, and monoclonal antimouse-MGI-2 antibody, which neutralizes MGI-2, also completely neutralizes this IL-6-induced differentiation. These results show that the major type of mouse myeloid differentiation-inducing protein (MGI-2A) and IL-6 are very similar and most likely identical proteins. Recombinant human IL-6 (also called interferon-β2 or B-cell differentiation factor), which shows only a 41 % similarity to mouse IL-6, has 11 identical amino acid residues out of the 22 in the mouse MGI-2A peptide and also induces differentiation of the same myeloid leukemic cells.