Biomedical subjects

G Merdrignac

Publications and source records attributed to G Merdrignac.

22 records · Page 2Linked to original sources

PubMed1983

[Relation between cyclic AMP and phagocytosis in human monocytes].

The involvement of cyclic adenosine 3'-5' monophosphate (cAMP) in the regulation of human monocyte phagocytosis of staphylococcus aureus in vitro was demonstrated by assay of adenylate cyclase (AC) and cAMP phosphodiesterase (PDE). Phagocytosis was associated with diminished AC activity (p less than 0,05) and concurrently increased PDE activity (p less than 0,005). Transmission electron microscopy provided evidence that these changes coincide with peak phagocytic activity occuring 10-20 minutes after the start of phagocytosis.

3',5'-Cyclic-AMP Phosphodiesterases↗

PubMed1982

A monoclonal antibody to the HLA-A3 alloantigen.

Monoclonal antibody production recognizing the HLA-A3 antigen is described. The XI-23 antibody reacted with all of the 89 cell suspensions carrying the HLA-A3 antigen (100% cytotoxicity) among a total of 191 suspensions tested. No extra-reactivity or cross-reactivity was observed, particularly with that of HLA-A11. This antibody can thus be considered as a good HLA-typing reagent.

Animals↗

PubMed1982

Changes in cAMP metabolism during phagocytosis of S. aureus by human monocytes.

Involvement of cyclic adenosine 3',5'-mono-phosphate (cAMP) in the phagocytosis of staphylococci by human monocytes was demonstrated by assay of adenylate cyclase and cAMP phosphodiesterase (PDE). Monocyte adenylate cyclase and PDE activities were assayed on cell homogenates prepared from monocytes isolated by plate adherence. Phagocytosis of staphylococci was associated with diminished adenylate cyclase activity, which reached a minimum after 10 min of incubation (p less than 0.05), and an increase in PDE activity (p less than 0.005). Transmission electron microscopy provided evidence that these changes coincide with peak phagocytic activity occurring between 10 and 20 min after the start of phagocytosis but could not be assigned to a particular stage in the phagocytic process.

3',5'-Cyclic-AMP Phosphodiesterases↗

PubMed1981

HLA-A, -B, and -DR specificities on human monocytes.

Monocyte-enriched cell suspensions obtained by a plate adherence method from 57 blood donors were typed by microcytotoxicity for HLA-A, -B and -DR determinants. Parallel assays were performed with autologous unfractionated lymphocytes for HLA-A and -B determinants and with autologous B-lymphocytes for HLA-DR determinants. Correlation coefficients (r values) were calculated for nine HLA-A specificities (r greater than 0.79), 16 HLA-B specificities (r greater than 0.56) and seven HLA-DR specificities (r greater than 0.81). For certain HLA-A and -B specificities detection was less readily achieved on monocytes than on autologous lymphocytes. Extra reactions were observed in some instances. With sera defining HLA-DR specificities, monocytes and B-cells showed reactivity of almost identical strength and reliability.

Antigens, Surface↗