Ig Heavy (ig + heavy)

Distribution by Scientific Domains


Selected Abstracts


IMGT standardized criteria for statistical analysis of immunoglobulin V-REGION amino acid properties

JOURNAL OF MOLECULAR RECOGNITION, Issue 1 2004
Christelle Pommié
Abstract IMGT, the international ImMunoGeneTics information system® (http://imgt.cines.fr) is a high-quality integrated information system specializing in immunoglobulins (IG), T cell receptors (TR) and major histocompatibility complex (MHC) of human and other vertebrates. IMGT comprises IMGT/LIGM-DB, the comprehensive database of IG and TR sequences from human and other vertebrates (76,846 sequences in September 2003). In order to define the IMGT criteria necessary for standardized statistical analyses, the sequences of the IG variable regions (V-REGIONs) from productively rearranged human IG heavy (IGH) and IG light kappa (IGK) and lambda (IGL) chains were extracted from IMGT/LIGM-DB. The framework amino acid positions of 2474 V-REGIONs (1360 IGHV, 585 IGKV, 529 IGLV) were numbered according to the IMGT unique numbering. Two statistical methods (correspondence analysis and hierarchic classification) were used to analyze the 237 framework positions (80 for IGHV, 79 for IGKV, 78 for IGLV), for three properties (hydropathy, volume and chemical characteristics) of the 20 common amino acids. Results of the analyses are shown as standardized two-dimensional representations, designated as IMGT Colliers de Perles statistical profiles. They provide a characterization of the amino acid properties at each framework position of the expressed IG V-REGIONs, and a visualization of the resemblances and differences between heavy and light, and between kappa and lambda sequences. The standardized criteria defined in this paper, amino acid positions and property classes, will be useful to study the mutations and allele polymorphisms, to establish correlations between amino acids in the IG and TR protein three-dimensional structures and to extract new knowledge from V-like domains of chains, other than IG and TR, belonging to the immunoglobulin superfamily. Copyright © 2004 John Wiley & Sons, Ltd. [source]


Expression of individual immunoglobulin genes occurs in an unusual system consisting of multiple independent loci

EUROPEAN JOURNAL OF IMMUNOLOGY, Issue 9 2004
Donna
Abstract Humoral immunity is effected through the rearrangement of immunoglobulin (Ig) genes in individual somatic cells committed to the B,lymphocyte lineage. Haplotype or allelic exclusion restricts B,lymphocytes to the expression of a single Ig receptor that can sustain further somatic modification. In most species, a specific Ig chain is encoded at a single genetic locus. However, in cartilaginous fish, hundreds of independent Ig heavy- (IgH) and Ig light-chain (IgL) gene loci are present, many of which are joined in the germ line. Ig gene transcripts have been amplified from single peripheral blood lymphocytes isolated from the clearnose skate (Raja eglanteria) using reverse-transcription PCR, and a single productive IgH transcript was detected in the majority of cells analyzed. Similarly, only a single IgL transcript was detected in over half of the individual cells. Taken together, these findings suggest that a mechanism for haplotype exclusion arose early in the evolution of antibody diversity and is independent of a single genetic locus. [source]


Dissemination of a Sjögren's syndrome,associated extranodal marginal-zone B cell lymphoma: Circulating lymphoma cells and invariant mutation pattern of nodal Ig heavy- and light-chain variable-region gene rearrangements

ARTHRITIS & RHEUMATISM, Issue 1 2006
A. Hansen
Objective Both the genesis and outgrowth of extranodal marginal-zone B cell lymphomas (MZLs) of the mucosa-associated lymphoid tissue (MALT) type are generally thought to represent antigen-driven processes. We undertook this study to analyze lymphoma progression and dissemination outside of the MALT-type lesions. Methods Histopathologic and Ig heavy- and light-chain variable-region gene (VH/L) analyses were performed in sequential tissue samples from a patient with primary Sjögren's syndrome (SS) with glandular (parotid) manifestations and subsequent nodal dissemination of a low-grade MZL. Results This MZL expressed a CD20+,CD27+,sIgM/,+,IgD,,CD5,,CD10,,Bcl-6,,CD23,,p53,,p21,,MDM2, phenotype and mutated VH1,69/D2,21/JH4,,V,A27/J,2 Ig rearrangements. Notably, circulating lymphoma cells from the parotid glands occurred transiently in the patient's blood, as detected by single-cell polymerase chain reaction. In addition, 2 minor B cell clones (clones 2 and 3, with VH3,07/D3,22/JH3b,V,3L/J,2/3 and VH3,64/D3,03/JH2,V,A19/J,2 rearrangements, respectively) were also detected in the parotid glands and blood, and 1 of these (clone 2) was also detected in the lymph nodes. Ig VH/L analyses revealed ongoing (antigen-driven) mutations of the glandular lymphoma rearrangements, but an invariant mutation pattern of their nodal counterparts. Conclusion These data indicate coexpansion and transient (re)circulation of the lymphoma clone and 2 additional glandular B cell clones in a primary SS,associated extranodal MZL. Combined histologic and molecular features of the nodal lymphoma subclone reflect a process of "follicular colonization" that eventually froze the mutation machinery after accumulation of additional (antigen-driven) Ig VH/L mutations. [source]