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C Lecou

Publications and source records attributed to C Lecou.

5 recordsLinked to original sources
PubMed1979

A new site-specific endonuclease showing phenotypical crypticity in a tumorigenic strain of Agrobacterium tumefaciens.

AtuBVI, an endonuclease showing new site-specificity, has been isolated from the tumorigenic strain IIBV7 of Agrobacterium tumefaciens, and is undetectable in the non-tumorigenic sister strain IIBNV6. AtuBVI degrades IIBV7 DNA in vitro and should, therefore, be regarded as being phenotypically cryptic in the bacterial cell; it also shows anomalous behavior under cerain incubation conditions. These properties point to a possible role for this enzyme in the insertion of exogenous Ti-plasmid DNA into plant tissues during tumorigenesis.

Coliphages↗
PubMed1976

Presence of blood group H antigen on a carcinoembryonic antigen, and its enzymatic modification into blood group A and B specificities.

A carcinoembryonic antigen (CEA-M) was purified from a hepatic metastasis obtained from a blood group O patient with cancer of the rectum. Using 125I-labeled carcinoembryonic antigen (CEA) and blood group antisera, H specificity has been found on the CEA-M. As the addition of anti-H to anti-CEA does not modify the extent of binding of labeled CEA-M to its antibodies (86%), the H and CEA determinants are carried by the same molecule. The affinity chromatography of CEA-M on an immunosorbent "anti-H-Sepharose" demonstrated that a proportion of CEA-M molecules might bear both H and CEA antigenic determinants. In addition, glycosyltransferases were used to modify the blood group H specificity into blood group A or B specificities.

ABO Blood-Group System↗
PubMed1975

[Presence of the H blood group antigen on a carcinoembryonic antigen (CEA). Enzymatic transformation of H to A and B specificities].

The carcinoembryonic antigen (CEA-M) was purified from a hepatic metastasis obtained from a blood group O patient with a cancer of the rectum. Using 125I-labelled-CEA and blood group antisera, H specificity was found on the CEA-M; the addition of anti-H to anti-CEA does not modify the binding of labelled-CEA-M to its antibodies (86%), this result leads us to conclude that H and CEA determinants are carried by the same molecule. However the low percentage of binding (30% with 1/10 anti-H) suggests that only a few CEA-M molecules do carry the H antigenic determinant. Finally, glycosyltransferases were used to modify the H specificity into blood group A and B specificities.

ABO Blood-Group System↗
PubMed1975

Enzymatic modification of the transplant antigens (ABO system) on human tumor cells.

Blood group glycosyltransferases were used to modify HeLa cells of H specificity (O Group) into cells of A and B specificity. We also obtained the identical type of modification with lymphocytes from healthy subjects and leukemia patients. This method can be applied to tumor cells in general, and constitutes an attempt to stimulate the immunocompetent system.

ABO Blood-Group System↗