A monoclonal antibody against a CEA-related antigen expressed on HT29 colon tumour cells.

A new monoclonal antibody, that binds to CEA and with low cross-reactivity with NCA, has been raised to an antigen expressed on HT29 colon tumour cells. This antibody (H58) reacts strongly with high-molecular-weight protein (50 X 10(4)) isolated from a crude plasma membrane preparation of HT29 cells as well as binding to purified CEA of molecular size (20 X 10(4)) isolated both from those cells and liver metastases of colon tumour. H58 binds to an epitope sterically unrelated to the binding site of the previously described anti-CEA monoclonal antibody MA/1 and our routine anti-CEA polyclonal serum PKIG. Augmented binding of antibody to either the cell membrane preparation or conventional CEA can be achieved using a mixture comprising equal weights of specific immunoglobulin from H58 and MA/1. The value of solid-phase binding assays using microtitre plates for selecting potentially useful antibodies is discussed.

Binding studies on two different monoclonal antibodies raised against CEA.

Binding characteristics of two mouse monoclonal antibodies MA/1 and MA/200 raised to carcinoembryonic antigen (CEA) are presented. Double antibody radioimmunoassay and a solid phase assay confirmed that MA/1 binds weakly to CEA extracted from tumour tissue but strongly to CEA in patients' serum. Antibody MA/200 binds with high affinity to both 'tumour' and 'serum' CEA. Ligand-receptor relationship for MA/1 and MA/200 binding to both tumour CEA and CEA isolated from serum are presented from equilibrium binding data analysed by the method of Scatchard. Co-titration experiments also indicated that MA/1 and MA/200 and an established polyclonal anti-CEA bind to a similar subpopulation of CEA or CEA-like molecules, but the binding data demonstrate that their respective binding sites are chemically different.

Immunoperoxidase localisation of human placental lactogen: a marker for the placental origin of the giant cells in 'syncytial endometritis' of pregnancy.

One hundred endometrial biopsies of various histological patterns, and material from 10 tubal pregnancies together with their associated uterine decidua, were examined for the presence of human placental lactogen using affinity-purified first and second antibodies and an indirect immunoperoxidase technique. Positive cells in endometrial curettings were seen only in association with an intrauterine pregnancy and morphologically resembled syncytiotrophoblast. Decidua associated with tubal pregnancy, pseudodecidua in progestogen-treated patients, and proliferative, secretory, and basal endometria were all negative. An immunoperoxidase stain for human placental lactogen is a useful marker for intrauterine pregnancy and supports the placental origin of the syncytial giant cells in so-called 'syncytial endometritis'. The technique is of potential value in those endometrial biopsies where pregnancy is suspected but no villi are seen.

Androgen trial in renal anaemia.

A double blind cross-over trial of Nandrolone decanoate (Decadurabolin) was carried out in 27 patients with anaemia due to end stage renal disease, stabilised on regular haemodialysis. Sixteen patients completed the study, the other patients being excluded from the final analysis for a variety of reasons including side effects related to the androgen. There was no sustained significant rise in haemoglobin concentration or in red cell mass. Erythropoietin levels did not alter, they were within or below the normal range, but were lower than would be expected for the degree of anaemia. A majority of patients reported increased well-being including exercise tolerance, appetite and libido. Voice changes and hirsutism were noted, mainly in the females. Instability of anticoagulant therapy and abnormalities in liver function were found in some patients. The benefits, though real, were restricted essentially to the improvement in subjective findings and were unrelated to laboratory measurements. These effects might be obtained with a lower dosage of the drug.