chimera

(redirected from chimaeric)
Also found in: Dictionary, Thesaurus, Encyclopedia.

chimera

 [ki-me´rah]
an organism whose body contains different cell populations derived from different zygotes of the same or different species, occurring spontaneously or produced artificially.

chi·me·ra

(kī-mēr'ă, ki-),
1. In experimental embryology, the individual produced by grafting an embryonic part of one animal onto the embryo of another, either of the same or of another species.
2. An organism that has received a transplant of genetically and immunologically different tissue, such as bone marrow.
3. Dizygotic twins that exchange immunologically distinct types of erythrocytes.
4. A protein fusion in which two different proteins are linked through peptide bonds; usually genetically engineered. Chimeric antibodies may have the Fab fragment from one species fused with the Fc fragment from another.
5. Any macromolecule fusion formed by two or more macromolecules from different species or from different genes.
[L. Chimaera, G. Chimaira, mythic monster (lit. a she-goat)]

chimera

also

chimaera

(kī-mîr′ə, kĭ-)
n.
1.
a. An organism, organ, or part consisting of two or more tissues of different genetic composition, produced as a result of organ transplant, grafting, or genetic engineering.
b. A gene or protein consisting of parts from two different genes or proteins that are normally distinct, sometimes derived from two different species.
2. An individual who has received a transplant of genetically and immunologically different tissue.

chimera

Any individual organism or molecule derived from 2 or more species.
 
Embryology
An organism that results when an embryonic part of one organism is grafted onto another.

Genetics
An organism with 2 or more cell lines, genotypes or karyotypes descended from at least 2 zygotes. Chimeras are very rare, only occur in twins and result from chorionic vascular anastomoses, transplantations or double fertilisations and subsequent participation of both fertilised meiotic products in one developing embryo; all hermaphrodites should be karyotyped to evaluate possible chimerism.

Molecular biology
(1) An animal formed from two different embryonic sources. In mouse genetics, targeted mutations produced in embryonic stem cells are recovered by breeding chimeric mice, resulting from the mixture of embryonic stem cells with a genetically distinct blastocyst.
(2) A clone containing genomic DNA from nonadjacent genomic segments or cDNA from two different mRNAs.

Transplantation
The term chimera was once used for a person who had received transplanted tissue—e.g., bone marrow surviving in a recipient.

chi·me·ra

(kī-mēr'ă)
1. The individual produced by grafting an embryonic part of one animal onto the embryo of another, either of the same or of another species.
2. An organism that has received a transplant of genetically and immunologically different tissue, such as bone marrow.
3. Dizygotic twins that have immunologically distinct types of erythrocytes.
4. A protein fusion in which two different proteins, usually from different species, are linked through peptide bonds; usually genetically engineered. Chimeric antibodies may have the Fab fragment from one species fused with the Fc fragment from another.
5. Any macromolecule fusion formed by two or more macromolecules from different species or from different genes.
[L. Chimaera, G. Chimaira, mythic monster (lit. a she-goat)]

chimera

An organism that contains a mixture of genetically different cells derived from more than one ZYGOTE. A chimera may, for instance, occur as a result of fertilization by more than one spermatozoon; fusion of two zygotes; an ALLOGENEIC bone marrow graft; cell exchange between dizygotic twin fetuses; or combination of portions of embryos of different species. Compare MOSAICISM. The term derives from the name of a mythical monster with a lion's head, a goat's body, and a serpent's tail.
References in periodicals archive ?
HIV-1 sub-type C chimaeric VLPs boost cellular immune responses in mice.
and Hoge, J.H., 1993, "A chimaeric tryptophan decarboxylase gene as a novel selectable marker in plant cells," Plant Mol.
Therapeutic antibodies have a high drug approval success rate once they reach clinical testing (29 per cent for chimaeric antibodies, 25 per cent for humanised antibodies compared to a success rate of approximately 11 per cent for small molecules).
In the study, the scientists placed the reprogrammed skin cells named ''induced pluripotent stem cells,'' or iPS cells, into other mouse's fertilized eggs and succeeded in creating chimaeric mice with two types of cells with reproductive functions.
To show that this is the case, we applied the AM-PM decomposition to generate chimaeric images (3) of the conventional Muller-Lyer configuration.
The resulting chimaeric virus particles are extremely immunogenic, giving better results than KLH conjugation and not requiring the addition of exogenous adjuvant.
Induction of male sterility in plants by a chimaeric ribonuclease gene.
More effective methods with smaller sets of chimaeric genes (with mixed characteristics), consisting of a suitable eukaryotic promoter, the gene sequence of interest, and a termination sequence, were then used (Davey et al., 1994).
Furthermore, in chimaeric mouse embryos with double mutations of SHP2 and FGF receptors, mutant cells failed to participate in the formation of the limb, suggesting SHP2-mediated FGF signaling pathway might mediate this effect [20].
[162] reported that IL-7 cannot support the in vivo expansion of adoptively transferred chimaeric antigen receptor- (CAR-) redirected CTLs because these effector-memory T cells, like Tregs, also lack IL-7R[alpha].