Biomaterial Database

Fc-receptor variants of a mouse macrophage cell line. 1979

J C Unkeless, and G Kaplan, and H Plutner, and Z A Cohn

Variants of the J774 mouse macrophage cell line that lack immunologically important membrane receptors were isolated. After mutagenesis, variants were selected in a metrizamide gradient that separated cells heavily rosetted with sheep erythrocytes (E) coated with rabbit anti-E IgG (EIgG) from poorly rosetted cells. Stable variants that exhibited altered binding were found with a frequency of <10(-7), and five clones were studied in detail. The variants failed to bind E opsonized with a monoclonal mouse IgG2b anti-E antibody but bound monomeric IgG2a normally when compared to the parental J774 line (K(a) 4 degrees C= approximately 1x10(8) M(-1); approximately 2x10(5) sites per cell). This demonstrates the independence of the receptor for mouse IgG2b complexes (FcRII) from the trypsin-sensitive receptor for mouse IgG2a monomer (FcRI). The variants bound an average of 10-15 EIgG per cell, compared to >20 per cell for J774. After trypsinization, three variants bound only three to five EIgG per cell; the J774 line was not affected by this treatment. Monomeric IgG2a could inhibit the binding of soluble rabbit IgG-antigen complexes to the variants but not to the parent line. Finally, E coated with IgM and complement (EIgMC) were bound poorly by all the variants, relative to the J774 parent. These results show that rabbit IgG complexes are bound by both FcRI and FcRII on mouse macrophages. The impairment of EIgMC rosetting in the variants suggests that the C3b receptor and FcRII are related.

UI	MeSH Term	Description	Entries
D007074	Immunoglobulin G	The major immunoglobulin isotype class in normal human serum. There are several isotype subclasses of IgG, for example, IgG1, IgG2A, and IgG2B.	Gamma Globulin, 7S,IgG,IgG Antibody,Allerglobuline,IgG(T),IgG1,IgG2,IgG2A,IgG2B,IgG3,IgG4,Immunoglobulin GT,Polyglobin,7S Gamma Globulin,Antibody, IgG,GT, Immunoglobulin
D007141	Immunoglobulin Fc Fragments	Crystallizable fragments composed of the carboxy-terminal halves of both IMMUNOGLOBULIN HEAVY CHAINS linked to each other by disulfide bonds. Fc fragments contain the carboxy-terminal parts of the heavy chain constant regions that are responsible for the effector functions of an immunoglobulin (COMPLEMENT fixation, binding to the cell membrane via FC RECEPTORS, and placental transport). This fragment can be obtained by digestion of immunoglobulins with the proteolytic enzyme PAPAIN.	Fc Fragment,Fc Fragments,Fc Immunoglobulin,Fc Immunoglobulins,Ig Fc Fragments,Immunoglobulin Fc Fragment,Immunoglobulins, Fc,Immunoglobulins, Fc Fragment,Fc Fragment Immunoglobulins,Fc Fragment, Immunoglobulin,Fc Fragments, Ig,Fc Fragments, Immunoglobulin,Fragment Immunoglobulins, Fc,Fragment, Fc,Fragments, Ig Fc,Immunoglobulin, Fc
D007700	Kinetics	The rate dynamics in chemical or physical systems.
D008264	Macrophages	The relatively long-lived phagocytic cell of mammalian tissues that are derived from blood MONOCYTES. Main types are PERITONEAL MACROPHAGES; ALVEOLAR MACROPHAGES; HISTIOCYTES; KUPFFER CELLS of the liver; and OSTEOCLASTS. They may further differentiate within chronic inflammatory lesions to EPITHELIOID CELLS or may fuse to form FOREIGN BODY GIANT CELLS or LANGHANS GIANT CELLS. (from The Dictionary of Cell Biology, Lackie and Dow, 3rd ed.)	Bone Marrow-Derived Macrophages,Monocyte-Derived Macrophages,Macrophage,Macrophages, Monocyte-Derived,Bone Marrow Derived Macrophages,Bone Marrow-Derived Macrophage,Macrophage, Bone Marrow-Derived,Macrophage, Monocyte-Derived,Macrophages, Bone Marrow-Derived,Macrophages, Monocyte Derived,Monocyte Derived Macrophages,Monocyte-Derived Macrophage
D008769	Methylnitronitrosoguanidine	A nitrosoguanidine derivative with potent mutagenic and carcinogenic properties.	Methylnitrosonitroguanidine,Nitrosomethylnitroguanidine,Nitrosonitromethylguanidine,MNNG,N-Methyl-N'-nitro-N-nitrosoguanidine,N Methyl N' nitro N nitrosoguanidine
D011955	Receptors, Drug	Proteins that bind specific drugs with high affinity and trigger intracellular changes influencing the behavior of cells. Drug receptors are generally thought to be receptors for some endogenous substance not otherwise specified.	Drug Receptors,Drug Receptor,Receptor, Drug
D002460	Cell Line	Established cell cultures that have the potential to propagate indefinitely.	Cell Lines,Line, Cell,Lines, Cell
D000818	Animals	Unicellular or multicellular, heterotrophic organisms, that have sensation and the power of voluntary movement. Under the older five kingdom paradigm, Animalia was one of the kingdoms. Under the modern three domain model, Animalia represents one of the many groups in the domain EUKARYOTA.	Animal,Metazoa,Animalia
D012397	Rosette Formation	The in vitro formation of clusters consisting of a cell (usually a lymphocyte) surrounded by antigenic cells or antigen-bearing particles (usually erythrocytes, which may or may not be coated with antibody or antibody and complement). The rosette-forming cell may be an antibody-forming cell, a memory cell, a T-cell, a cell bearing surface cytophilic antibodies, or a monocyte possessing Fc receptors. Rosette formation can be used to identify specific populations of these cells.	Immunocytoadherence,Formation, Rosette,Formations, Rosette,Immunocytoadherences,Rosette Formations
D014644	Genetic Variation	Genotypic differences observed among individuals in a population.	Genetic Diversity,Variation, Genetic,Diversity, Genetic,Diversities, Genetic,Genetic Diversities,Genetic Variations,Variations, Genetic