What is IgH rearrangement?
What is IgH rearrangement?
Immunoglobulin heavy chain (IgH) gene rearrangement test is a standard tool in diagnosing B-cell lymphoma. The BIOMED-2 multiplex PCR protocol has become the most commonly used laboratory method for detecting clonal IgH gene rearrangement.
What happens during the rearrangement of immunoglobulin genes?
Immunoglobulin heavy-chain gene rearrangement begins in early pro-B cells with D to JH joining. This typically occurs at both alleles of the heavy-chain locus, at which point the cell becomes a late pro-B cell. The cell then proceeds to rearrange a VH gene segment to the DJH sequence.
How many Vdj combinations are possible?
DNA rearrangement causes one copy of each type of gene segment to go in any given lymphocyte, generating an enormous antibody repertoire; roughly 3×1011 combinations are possible, although some are removed due to self reactivity.
What is Vdj sequencing?
Here, we describe VDJ sequencing (VDJ-seq), which accurately quantitates immunoglobulin diversity at the DNA level in an unbiased manner. This is accomplished with a single primer-extension step using biotinylated J gene primers.
What is IgH test?
The IgH Clonality by NGS test is designed to detect clonal populations of B-lymphocytes in a given patient sample through the analysis of the VDJ segment of the immunoglobulin heavy chain (IgH) gene. Detecting the presence of clonal B-lymphocyte populations is important for the diagnosis of B-cell lymphoma or leukemia.
What causes somatic hypermutation?
Somatic hypermutation involves a programmed process of mutation affecting the variable regions of immunoglobulin genes. Unlike germline mutation, SHM affects only an organism’s individual immune cells, and the mutations are not transmitted to the organism’s offspring.
What is the 12 23 rule?
The 12/23 rule, which is mediated at the level of RAG-1/2 recognition and cutting4,5, specifies that V(D)J recombination occurs only between a gene segment flanked by a 12-RSS and one flanked by a 23-RSS1.
How does gene rearrangement occur?
Gene rearrangement is a phenomenon in which a programmed DNA recombination event occurs during cellular differentiation to reconstitute a functional gene from gene segments separated in the genome.
What does VDJ stand for Immunology?
variability, diversity
VDJ stands for variability, diversity, and joining, respectively, and VDJ rearrangement has 4 key characteristics that help ensure that each antigen receptor is unique.
What does Vdj stand for?
VDJ
| Acronym | Definition |
|---|---|
| VDJ | Variable Diversity Joining (biochemistry) |
| VDJ | Voices of Development Jurists (International Development Law Organization) |
| VDJ | Virtual Disc Jockey (music mixing software) |
| VDJ | Variable-Diversity-Junctional (genes) |
What is clonal immunoglobulin gene rearrangement?
Detection of a predominant immunoglobulin gene rearrangement profile often indicates the presence of a clonal B-cell population. This can help establish the diagnosis of a B-cell lymphoma or evaluate for residual or recurrent disease after treatment.
How are VJ K and C K regions rearranged?
First, if 5′ V K and 3′ J K segments remain still available, secondary VJ K rearrangements can occur, rendering a new (functional) VJ K rearrangement (B1). Alternatively, deletional rearrangements via Kde can occur, with excision of the C K region as shown or with deletion of the entire J K -C K region through direct V K to Kde recombination (B2).
What happens when the VDJ H gene is mutated?
If this VDJ H is functional, the cell will develop into a mature B-cell–expressing surface IgM (IgM + ). These cells can enter the GCs where SHM and CSR occur, thus becoming VH-mutated, class-switched (eg, IgA) memory B or plasma cells. Circles preceding the C H gene segments (except δ) represent the switch regions.
When do IGK and IGL gene rearrangements occur?
Schematic diagram of the ordered IGK and IGL gene rearrangement and SHM during B-cell development. At the pre-B cell stage, after IGH rearrangements have been completed and a μ heavy chain is produced, recombination at the IGK locus occurs between a V K and a J K segment.
How many HCV + patients have heavy chain VDJ?
For 22 HCV + patients and 7 healthy controls, we performed high-throughput sequencing of immunoglobulin heavy chain VDJ rearrangements of naive, mature CD5 +, IgM + memory, and class-switched memory B cells.