Purification of murine suppressive factor of allergy into distinct CD23-modulating and IgE-suppressive proteins.
The murine suppressive factor of allergy (SFA) has been purified from a T-cell hybridoma and found to consist of two functionally and biochemically distinct protein molecules. One protein (17 kDa) modulates the low-affinity Fc receptor for IgE on lymphocytes (i.e., CD23); it decreases the binding avidity of IgE to CD23-bearing B cells without affecting quantitative expression of CD23 and is thus designated epsilon-receptor-modulating protein. The second protein (30 kDa) suppresses IgE biosynthesis (i.e., SFA). This purified SFA suppresses interleukin 4-induced IgE and IgG1 synthesis by lipopolysaccharide-activated spleen cells but has no effect on other antibody isotypes; since the activity of SFA is not blocked by anti-interferon gamma monoclonal antibody, it is thus distinct from interferon gamma. The data presented indicate that epsilon-receptor-modulating protein and SFA are protein molecules that are involved in modulating the CD23 molecule and IgE antibody synthesis, respectively.
Matsushita
S
S
Division of Immunology, Medical Biology Institute, La Jolla, CA 92037.
Marcelletti
J F
JF
Katz
L R
LR
Katz
D H
DH
D000818:Animals; D000917:Antibody Formation; D000944:Antigens, Differentiation, B-Lymphocyte / Q000276:immunology*; D002850:Chromatography, Gel; D002851:Chromatography, High Pressure Liquid; D004591:Electrophoresis, Polyacrylamide Gel; D005260:Female; D007073:Immunoglobulin E / Q000276:immunology*; D007074:Immunoglobulin G / Q000276:immunology; D007166:Immunosuppressive Agents / Q000276:immunology / Q000302:isolation & purification*; D007371:Interferon-gamma / Q000276:immunology; D008214:Lymphocytes / Q000276:immunology*; D051379:Mice; D008807:Mice, Inbred BALB C; D009930:Organic Chemicals; D011961:Receptors, Fc / Q000276:immunology*; D017455:Receptors, IgE; D013601:T-Lymphocytes / Q000276:immunology
D000944:Antigens, Differentiation, B-Lymphocyte; D007074:Immunoglobulin G; D007166:Immunosuppressive Agents; D009930:Organic Chemicals; D011961:Receptors, Fc; D017455:Receptors, IgE; C023051:suppressive factor of allergy; D007073:Immunoglobulin E; D007371:Interferon-gamma