This chapter presents comments on clonal and nonclonal selection and expansion of B cells. Studies carried out in mice, rats, and rabbits have shown that after the injection of an antigen, two population of cells appeared: cells synthesizing and secreting antibodies directed against the antigen ...
Similar results were obtained in splenic fragment culture with cells from neonatal livers and spleens. PC-specific precursors were detected in the liver of 1-d-old neonates, whereas the spleen of those animals contained no precursors for PC. Precursors for PC residing in the neonatal liver are ...
Related to clonal expansion:Clonal selection (klōn) n. 1.A group of cells or organisms that are descended from and genetically identical to a single progenitor, such as a bacterial colony whose members arose from a single original cell. ...
Notably, GI tract clones display extensive sharing of sequence variants among different portions of the tract and have higher frequencies of somatic hypermutation, suggesting extensive and serial rounds of clonal expansion and selection. Our findings provide an anatomic atlas of B-cell clonal lineages,...
Genetic mutation provides cells with the potential to be positively selected and may ultimately lead to clonal dominance [39]. Malignant development may be induced if cells acquire substantial pro-survival mutations that confer unlimited growth and expansion [45]. Thus, understanding the acquisition and...
1, HMOX1), and DNA damage (OGG1, PARP-1) markers were significantly upregulated at R + 3 compared to baseline (10 days before flight) in isolated PBMCs29, suggesting spaceflight contributes to significant physiological stress, which may be an impetus for clonal selection and expansion. ...
This hypothesis is based on the notion that somatic mutations are rare events that are unlikely to co-occur in different single normal cells, and that the mutations leading to the genetic diversification of the tumor architecture occur during the process of clonal expansion and selection. A cancer...
When mutator clones acquire increased fitness due to a mutation, they can undergo selection and clonal expansion, further accelerating subseqent steps in carcinogenesis (Nowell 1976). We term this phenomenon “positive clonal selection” of mutator clones. ...
BCR clonal structures across metastatic sites were also correlated with TCRα and TCRβ clonal structures, indicating shared factors driving B cell and T cell infiltration and selection (Fig. 2b). This was confirmed by deconvoluting tumor immune microenvironment composition and activity20 from the ...