IgG1, IgG2a, and IgG2b, passively administered with soluble Ags, enhance specific Ab responses. The effect of IgG3 in this type of feedback regulation has not been studied previously. We immunized mice with trinitrophenyl (TNP)-coupled carrier proteins (bovine serum albumin [BSA] or ovalbumin [OVA]) alone or complexed to monoclonal TNP-specific IgG3. The carrier-specific Ab responses were enhan...

A gamma-chain variant with a lower molecular weight than the normal gamma chain was detected in a new congenital abnormal fibrinogen with impaired polymerization of the fibrin monomer and with normal release of fibrinopeptides A and B in a 45-year-old male. Purified fibrinogen analyzed on SDS-polyacrylamide gel electrophoresis under the reduced condition contained an abnormal protein band with ...

The mast cell receptor with high affinity for IgE consists of four transmembrane polypeptides which are held together by detergent-sensitive interactions: an IgE-binding alpha chain, a single beta chain, and a disulfide-linked dimer of gamma chains. Now that the cDNAs that code for each of the subunits have been isolated, it should be possible to probe by site-specific mutations, which portions...

As a component of various cytokine receptors, common cytokine receptor gamma-chain (gamma(c)) is essential in the development of the immune system and plays an important role in different stages of inflammatory and immune responses. Here we establish that resting CD4 T cells and the Jurkat CD4 T cell line do not express the mature form of gamma(c) (64 kDa) recognized by mAb Tugh4. However, thes...

The recent discovery of molecular defects in three forms of X-linked immunodeficiency has quickly transformed the study of immunodeficiency into one of the most exciting in basic and clinical immunology. The identification of defects in the IL-2R gamma chain in the etiology of X-linked SCID has suggested a heretofore unanticipated functional role of the gamma chain in immunologic development. W...

background : peroxisome proliferator-activated receptor gamma (ppar γ) is a transcription factor, which is abundantly expressed in adipose tissue and has a direct link to adiposity. it seems that long-chain polyunsaturated fatty acids (lc-pufas) can regulate ppar γ expression. the purpose of this study was to investigate the effects of n-3lc pufa supplementation on plasma levels of ppar γ and t...

The authors describe a patient who presented an association of hairy cell leukemia (HCL) and large granular lymphocyte (LGL) leukemia. An eventual relationship between these two rare entities is analyzed. Hairy cells (HCs) were present in the blood, bone marrow, and spleen. An excess of LGLs was found only in the blood and bone marrow. After splenectomy the patient received an alpha 2-interfero...

Complete deficiency of either of the two human interferon (IFN)-gamma receptor components, the ligand-binding IFN-gammaR1 chain and the signaling IFN-gammaR2 chain, is invariably associated with early-onset infection caused by bacille Calmette-Guérin vaccines and/or environmental nontuberculous mycobacteria, poor granuloma formation, and a fatal outcome in childhood. Partial IFN-gammaR1 deficie...

Receptors for the Fc portion of Ig (Fc receptors, FcR) are found on all cell types of the immune system. Three types of FcR react with IgG: Fc gamma RI is a high-affinity receptor binding IgG monomers whereas Fc gamma RII and Fc gamma RIII are low-affinity receptors binding IgG immune complexes; the three types of Fc gamma R are members of the Ig superfamily. Two FcR react with IgE:Fc epsilon R...