What is clonality testing?
A clonality test for immunoglobulin (IG) and T cell receptor (TCR) is a useful adjunctive method for the diagnosis of lymphoproliferative diseases (LPDs). Recently, the BIOMED-2 multiplex polymerase chain reaction (PCR) assay has been established as a standard method for assessing the clonality of LPDs.
What is cell clonality?
Clonality implies the state of a cell or a substance being derived from one source or the other. Thus there are terms like polyclonal—derived from many clones; oligoclonal—derived from a few clones; and monoclonal—derived from one clone. These terms are most commonly used in context of antibodies or immunocytes.
What is TCR clonality?
TCRβ clonality was defined as the number of abundant TCRβ clonotypes adjusted by TRB mRNA expression, as shown below: TCR β clonality = Number of TCR β clonotypes < 0.1 % frequency TRB mRNA expression.
What is B cell clonality?
Clonality analysis of B-cell populations can aid in the diagnosis of lymphoproliferative disorders. This test is used to support or refute the diagnosis of B-cell lymphomas/leukemias.
What is gene rearrangement testing?
A laboratory test in which cells in a sample of blood or bone marrow are checked to see if there are certain changes in the genes that make receptors on T cells (white blood cells).
What is B-cell gene rearrangement?
B-cell immunoglobulin gene rearrangement tests are used to help diagnose non-Hodgkin B-cell lymphomas and evaluate for residual or recurrent disease after treatment. There are many different types of B-cell lymphoma and each has different characteristics, prognoses, and a likely response to therapy.
What is clonal proliferation?
Clonal proliferation describes the selection and reproduction of only one type of cell.
What is clonal population?
Mutations within clones of asexual populations give rise to clonal lineages. In contrast to recombining populations, clonal populations are characterized by lack of recombination among loci and lack of segregation of alleles at single loci in diploids.
How do you calculate TCR clonality?
The clonality of the TCR repertoire was calculated as 1-Pielou index, which was calculated using the formula 1+ ∑ni=1(pi∗ln(pi))/ln(n), where pi is the frequency of clone i for a sample with n unique clones. Of note, this metric is normalized to the number of unique clones and ranges from 0 to 1.
What is an 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.