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C Willem

Publications and source records attributed to C Willem.

11 recordsLinked to original sources
PubMed1998

Shared epitopes of glycoprotein A and protein 4.1 defined by antibody NaM10-3C10.

We have produced the murine monoclonal antibody (MAb) NaM70-3C10 (IgM) from splenocytes of mice immunized with human red blood cells (RBCs). The MAb agglutinated untreated as well as trypsin, chymotrypsin, neuraminidase, or ficin-treated RBCs from controls. In contrast, control RBCs treated with papaine or bromelaine were not agglutinated. On immunoblots, the MAb bound to glycophorin A (GPA) and to a 80 kDa protein identified as protein 4.1. Analysis by agglutination of variant RBCs carrying hybrid glycophorins made of the N-terminus (amino acids 1-58) of GPA and of the C-terminus (amino acids 27-72) of glycophorin B (GPB) and competition-inhibition test using purified GPA and a synthetic peptide corresponding to the amino acid sequence 48-58 of GPA demonstrated that the epitope is located within residues 48-58 of GPA. Epitope analysis with immobilized peptides showed that the MAb recognizes the sequence 53Pro-Pro-Glu-Glu-GIu58 of GPA. A homologous sequence is also present within amino acids 395 to 405 of protein 4.1. Finally, the MAb bound to 16 kDa chymotryptic peptide of protein 4.1, which carries the above amino acid sequence. In conclusion, it may be assumed that NaM70-3C10 specifically recognizes a common epitope on the extracellular domain of GPA and on the intracellular protein 4.1; this specificity explains the persistence of the 80 kDa band on blots when RBCs are treated with papain.

Amino Acid Sequence↗
PubMed1997

Immunochemical characterisation of monoclonal antibodies directed to glycophorins A and/or B.

Among sixty-nine monoclonal antibodies submitted to the workshop, 28 antibodies directed to glycophorins A and/or B but without blood group specificity were investigated by a series of methods involving agglutination, flow cytometry with CHO transfected cells expressing glycophorin A, ELISA with a carbohydrate-free peptide (residues 1-72) of glycophorin A, and immunoblotting. These MAbs were subdivided in several groups according to their specificity: N-terminal portion of GPA and GPB; N-terminal trypsin-sensitive portion of GPA; extracellular ficin-sensitive portion of GPA; intracellular domain of GPA; undetermined. Both flow cytometry with transfectant cells and ELISA with the synthetic peptide prove to be of value in order to determine subspecificities within these groups.

Agglutination Tests↗
PubMed1997

Flow cytometry and immunoblotting analysis of monoclonal antibodies directed to complement regulatory proteins.

A series of 18 monoclonal antibodies directed to complement regulatory proteins were investigated by flow cytometry and immunoblotting. Seventeen antibodies are directed against a phosphatidyl inositol-linked glycoprotein since they show a dual population of erythrocytes from a paroxysmal nocturnal haemoglobinuria (PNH) patient. From this group, 6 antibodies revealed a 65-70 kDa band on immunoblots allowing their identification as anti-DAF (Decay Accelerating Factor; CD55 antigen), and 11 bound to a 20 kDa molecule corresponding to MIRL (Membrane Inhibitor of Reactive lysis, CD59 antigen). One antibody revealed an homogeneous population from the PNH patient and bound to a 200 kDa band on immunoblot that might corresponds to the CR1 (Complement Receptor type 1; CD35).

Antibodies, Monoclonal↗
PubMed1997

[Recurrent urethral stenosis treated with a Urolome Plus stent implantation: intermediate multicenter follow-up].

We present the medium-term results of 33 patients treated with Urolume Plus urethral stent between August 1990 and June 1996 in 9 Belgian and Luxembourg centers. They all had previous treatments for bulbo-membranous urethral stricture, but without sustained benefit (dilatation, internal urethrotomy, or/and urethroplasty). The mean age of the stricture was 5.4 years (+/- 4). The stent was inserted easily during a short hospitalisation. Median time of follow-up is two years (6 months to 4 years). Maximum flow rate at last follow-up was 20.7 ml/sec (+/- 7), and 83.3% of the patients were satisfied with the stent. In 70% of the cases, the stent achieved its purpose of maintaining a good urethral lumen. In 5 patients (15.15%), stricture recurred inside the stent and in 2 patients (6.06%) a new stricture appeared on another site. Among these 7 patients, 5 were satisfactorily treated by endoluminal resection (4 cases) or dilatation (1 case). There were 2 real failures (= 6%): one patient who has refused any complementary endoscopic treatment and the other one who is still undergoing repeated urethral dilatations. Having respected the right indications for this device, we are satisfied of the results. It is a good alternative after failure of other treatments for bulbar-membranous stricture.

Anesthesia↗
PubMed1996

Production and properties of monoclonal antibodies against human IgG isotypes.

Several monoclonal antibodies (MAbs) against human IgG isotypes were obtained by the fusion of myeloma cells with splenocytes from mice immunized with IgG fractions extracted from human plasma. Four MAbs (F7H7, D4F8, B12A8, and E7E10) were selected by an ELISA technique on the basis of their ability to detect one of the four IgG subclasses. Their specificity was checked using a panel of pure myeloma proteins representative of the main allotypes present on IgG isotypes. In addition, two other MAbs (F3E12 and E6D6) were found able to detect specifically kappa or lambda light chains. The immunochemical properties of these MAbs were analyzed mainly in respect to their capacity to detect and to purify the different human IgG isotypes. The following data were obtained: (1) The ability of the MAbs F7H7, D4F8, B12A8, and E7E10 to measure the concentration of each IgG subclass in serum was estimated by an immunocapture ELISA. Results obtained with the new antibodies were compared with several other MAbs recommended by the IUIS/WHO human Immunoglobulins subcommittee. Similar or better results were obtained with the new anti-IgG1, anti-IgG3, and anti-IgG4, MAbs. (2) The same MAbs were tested for their ability to purify a single IgG subclass from IgG preparations and from normal and pathological sera. Fractions containing about 80% of purified IgG1, IgG3, and IgG4 were obtained after one-step immunoaffinity purification. Consequently, these MAbs proved to be useful to detect, to measure and to purify IgG subclasses.

Animals↗
PubMed1991

Characterization of murine monoclonal antibodies directed against the Kell blood group glycoprotein.

Murine monoclonal antibodies (MoAbs) were produced against the blood group KEL1 glycoprotein (93 kD component) immunopurified from human erythrocytes. One monoclonal antibody, 5A11 (IgGa, kappa), detects by immunoblotting a 93 and 184 kD component from KEL: 1,-2 or KEL: -1,2 red cell membrane preparations, separated by SDS polyacrylamide gel electrophoresis (PAGE) under non-reducing conditions. The 184 kD component was not detected under reducing conditions, suggesting that it represented a dimer of the 93 kD KEL glycoprotein. Neither the 93 nor the 184 kD could be detected from K0 or McLeod erythrocyte membrane preparations, indicating that the monoclonal antibody reacts with the KEL glycoprotein previously identified as a 93 kD species. Since this antibody does not agglutinate native or protease-treated erythrocytes, it is likely that it reacts with the cytoplasmic domain of the KEL glycoprotein. This was also substantiated by showing that 5A11 could immunoprecipitate the 93 kD component from intact membranes and inside-out vesicles but not from right-side-out vesicles. Immunostaining of membrane proteins prepared from human blood cells (platelets, lymphocytes, monocytes and granulocytes) and non-human erythrocytes revealed that the 93 kD molecule was only present on human red cells. Several other murine monoclonal antibodies obtained from the same fusion experiment gave identical results, but competition analyses on immunoblots indicated that these antibodies reacted with distinct epitopes on the KEL glycoprotein.

Animals↗
PubMed1977

Sexual behaviour after prostatectomy.

Sexual behaviour after prostatectomy has been observed in 100 patients who have undergone a Millin prostatectomy with preventive haemostasis. The results have been compared with 100 patients subjected to other urological operations and 100 patients who have undergone general surgical operations. From the data obtained we conclude that: (1) one third of the patients who have undergone prostatectomy no longer have sexual activity; (2) prostatectomy does not affect sexual potency more than any other operation of the same gravity at the same age; (3) among the patients sexually active 6 months before prostatectomy, 45% have a better sexual life 6 months afterwards, 26% have a diminished sexual life and 3.5% have become impotent; (4) the development of an adenoma seems to have an unfavourable influence on sexual activity.

Adult↗