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A Ritson

Publications and source records attributed to A Ritson.

15 recordsLinked to original sources
PubMed1991

Granulated lymphocytes in human endometrium: histochemical and immunohistochemical studies.

Granulated lymphocytes with an unusual antigenic phenotype (CD56+ CD38+ CD2 +/- CD3- CD16-) form a substantial proportion of leukocytes in human endometrial stroma. The purpose of this study was to examine morphological and antigenic heterogeneity in endometrial granulated lymphocytes (eGL) in imprint preparations, paraffin-embedded sections and frozen sections. eGL in decidual imprints showed variations in cell size, nuclear size, shape and chromatin content and the number and size of cytoplasmic granules. eGL were detected in paraffin-embedded sections using phloxine tartrazine, alcian blue and toluidine blue stains. There was no difference in the number of eGL among the three stains but the granules appeared smaller and more regular when stained with toluidine blue. The proportion of stromal cells which were leukocytes increased from 8.2% in proliferative endometrium to 31.7% in early pregnancy decidua. The number of CD56+ and CD38+ cells increased in late secretory endometrium; CD56+ cells formed greater than 75% of the leukocytes in first trimester decidua. The increased number of CD2+ cells in decidua was not comparable with CD56+ and CD38+ cells suggesting that a lower proportion of CD56+ cells in first trimester decidua coexpress CD2, an observation which was supported by double labelling studies. eGL therefore show morphological and antigenic heterogeneity and the study of granulated lymphocytes in pathological endometrium and decidua will require careful phenotypic and morphological analysis of accurately dated samples.

Antibodies, Monoclonal↗
PubMed1989

Isolation and functional studies of granulated lymphocytes in first trimester human decidua.

Granulated lymphoid cells (CD2+, CD7+, CD38+, NKH1+, CD3-, CD5-, CD4-, CD8-, CD25-) are prominent in human endometrial stroma in the late secretory phase of the menstrual cycle and in early pregnancy, and may play an important role in implantation and placentation. Cell suspensions enriched for granulated lymphoid cells were prepared from first trimester human decidua using a panning technique; cells were labelled with the monoclonal antibody NKH1 and separated by adherence to immunoglobulin-coated plates. The enriched cells were characterized with a panel of monoclonal antibodies using an indirect immuno-alkaline phosphatase method, and subjected to various functional assays. Most cells in the enriched preparations showed the characteristic morphology of granulated lymphocytes in smears stained with toluidine blue or May Grunwald Giemsa. CD45+ cells were obtained up to 98 +/- 1% purity (n = 10) and CD2+ cells were enriched up to 84 +/- 4%. The enriched populations were efficient effectors in a K562 chromium-release assay but showed minimal proliferative response to phytohaemagglutinin, concanavalin A, ionomycin and phorbol 12, 13 dibutyrate (PdBU), interleukin 1 or interleukin 2. The precise lineage and in vivo function of decidual granulated lymphocytes remains to be established.

Decidua↗
PubMed1988

Immunoregulatory cells in human decidua: morphology, immunohistochemistry and function.

Suggestions that local intrauterine materno-fetal immune interactions may be important for normal pregnancy have led to investigation of immunoregulatory function by decidualised endometrium. Human decidua is complex and cell types may be difficult to distinguish at the light microscope level. Immunohistochemical techniques have allowed antigenic identification of cells within decidua and abundant leucocytes are present throughout pregnancy. Macrophages (CD14+) are abundant in decidua basalis and decidua parietalis throughout pregnancy and may be closely associated with extravillous trophoblast. Expression of class II MHC antigens and CD11c may suggest an immunological role but their content of lysosomal enzymes could indicate phagocytic functions. Antigen-presenting capacity has been noted in early human decidua and may be due to macrophages. Decidual macrophages have also been attributed with immunosuppressive function due to secretion of prostaglandin E2. Decidual granulated lymphocytes are abundant in the first trimester and correspond to the so-called endometrial stromal granulocytes. They express CD2, CD7, CD38 and NKH1 but are negative for classical T cell and NK cell markers and they do not express the IL2 receptor. Semipurified populations show low levels of cytotoxicity in a standard NK assay. Thus, immunohistochemical techniques have allowed characterisation of potentially immunocompetent cells in human decidua. However, their roles both in vitro and in vivo remain to be established with certainty.

Antigens, Surface↗
PubMed1987

Extraction of leucocytes from human decidua. A comparison of dispersal techniques.

Functional studies of human utero-placental tissues have been limited by poor characterisation of the morphology and antigenic phenotype of the cells under investigation. The present study documents the effect of dispersal methods on the viability and cellular composition of cell suspensions prepared from decidualised endometrium in early human pregnancy. First trimester decidua was subjected to both mechanical disaggregation and digestion with various enzyme combinations in an attempt to optimise the yield of infiltrating decidual leucocytes. Cell types were characterised with monoclonal antibodies using an alkaline phosphatase immunolabelling method. Mechanical disaggregation resulted in suspensions containing many large decidual cells and much cell debris but few leucocytic cells. Overall viability was low, although the viability of small leucocytes common antigen-bearing cells remained high. Enzymic digestion yielded cell suspensions rich in leucocytes with high viability and minimal contamination by other cell types. Collagenase produced a high yield of leucocytes with high viability and minimal disruption of surface antigens in contrast with pronase which caused extensive antigenic loss. The disaggregation method determines the yield of bone marrow derived cells in decidual cell suspensions and the extent of contamination by true decidual cells and epithelial cells.

Antibodies, Monoclonal↗
PubMed1987

Immunocytochemical evidence that endometrial stromal granulocytes are granulated lymphocytes.

Endometrial stromal granulocytes (EGs) are prominent in late luteal phase human endometrium and in early pregnancy decidua. They have been believed to develop from endometrial stromal cells and to secrete relaxin. Recent immunohistochemical studies have suggested that EGs are derived from bone marrow but this has been difficult to prove, mainly because the characteristic cytoplasmic granules are not preserved in frozen tissues. Two separate approaches have now been employed to investigate the cellular lineage of EGs. Formalin-fixed paraffin-embedded sections of first trimester decidua were labelled by an immunoperoxidase method with four monoclonal antibodies (mAbs) reactive with routinely fixed and processed tissues. In addition, acetone-fixed smears of decidual cell suspensions were labelled with a panel of mAbs. Sections and smears were counterstained to demonstrate the characteristic cytoplasmic granules of EGs. Endometrial granulocytes were LCA+, CD2+, MT1+, and UCHL1+, which provides evidence that they are leucocytes. EGs are probably members of the large granular lymphocytes series and may have an essential role in normal implantation and placentation.

Antibodies, Monoclonal↗
PubMed1987

Reticuloendothelial system phagocytic function in obstructive jaundice and its modification by a muramyl dipeptide analogue.

Measurement of reticulo-endothelial system (RES) phagocytic function by clearance of intravenous micro-aggregated human albumin (HMAA) showed prolonged clearance in both patients (p less than 0.001) and rats (p less than 0.001) with extrahepatic biliary tract obstruction compared with non-jaundiced controls. After the administration of the immune stimulator, N-acetyl-L-alpha-aminobutyryl-D-isoglutamine, the mean HMAA clearance rate in jaundiced animals was similar to that of non-jaundiced controls. The implications of modifying RES phagocytic function to prevent overspill of endotoxins from the portal to systemic circulation in obstructive jaundice are discussed.

Acetylmuramyl-Alanyl-Isoglutamine↗
PubMed1987

Endometrial granulocytes in human decidua react with a natural-killer (NK) cell marker, NKH1.

Lymphoid cells in decidualized uterine endometrium in early human pregnancy may be essential for successful implantation and placentation. Endometrial granulocytes are prominent in early pregnancy decidua and express some T-cell associated surface antigens (CD2+, CD7+), but little is known of their function. We report the unusually intense binding of the natural-killer (NK) cell marker NKH1 to endometrial granulocytes, which contrasts with their lack of reactivity with other NK-cell markers.

Antibodies, Monoclonal↗
PubMed1986

Monoclonal immunoscintigraphy for the detection of primary colorectal cancers: a prospective study.

A prospective study to investigate the value of monoclonal antibody (McAb) immunoscintigraphy for the detection of primary tumours of the colon and rectum has been undertaken. Twelve patients received 1 mg 131I-labelled McAb YPC 2/12.1, an antibody raised to a human colonic carcinoma membrane preparation. Imaging of the blood pool was achieved using 99mTc-labelled red cells. After surgery specimens were scanned and samples of normal and malignant tissue excised to obtain antibody binding ratios. In only one patient was the primary tumour visualized pre-operatively. Images of the resected specimens revealed the primary tumour in ten cases but this appeared to be a function of increased blood pool within the tumour rather than specific antibody localization. The mean tumour/normal tissue count ratio was 1.27:1 (range 0.63:1-1.93:1). It is concluded that the McAb YPC 2/12.1 is unlikely to be of use clinically. Furthermore when selecting McAbs for the purposes of immunoscintigraphy the results of in vitro binding to malignant cell lines, immunohistological studies and xenograft experiments may be misleading and careful clinical evaluation is necessary.

Antibodies, Monoclonal↗
PubMed1986

Primary hepatocellular carcinoma localised by a radiolabelled monoclonal antibody.

A rat monoclonal antibody, YPC2/38.8, was selected from a panel of antibodies derived by immunising rats with fresh human colorectal carcinoma. It was found to bind to a 30 000 dalton protein present on the cell surface of normal colon and liver. This protein was increased 10-fold on primary hepatocellular carcinoma (PHC) cells. After labelling with 131I, YPC2/38.8 was shown to localise human PHCs grown as xenografts in immunosuppressed mice. Sixteen patients with PHC were given 1 mg of purified antibody labelled with 1 mCi of 131I by slow intravenous injection. In 8 out of 9 patients with PHC arising in non-cirrhotic livers, good tumour images were obtained on gamma camera or rectilinear scans, but in 7 patients who had developed PHC on the background of established hepatic cirrhosis, no tumour images were seen. Subsequent studies revealed that the 30K antigen recognised by this antibody was present in increased quantity on PHC cells and the regenerating liver cells in cirrhosis. We conclude that YPC2/38.8 may have potential for diagnostic localisation and possibly thence for the selective targeting of drugs or toxins in patients with PHC arising in a liver unaffected by significant parenchymal disease.

Adolescent↗
PubMed1986

Localisation of lung cancer by a radiolabelled monoclonal antibody against the c-myc oncogene product.

A set of mouse nonoclonal antibodies against the c-myc oncogene product, a 62,000 dalton nuclear binding protein involved in cell cycle control, has been constructed by immunisation with synthetic peptide fragments. One such antibody, CT14, was radiolabelled with 131I and administered to 20 patients with different malignant diseases. Good tumour localisation was observed in 12 out of 14 patients with primary bronchial carcinoma but not in patients with pulmonary metastases from primary tumours elsewhere. Successfully localised tumours were all 3 cm or more in diameter. Monoclonal antibodies against oncogene products may provide novel selective tools for the diagnosis and therapy of cancer.

Adult↗
PubMed1986

The clinical significance of flow cytometric c-myc oncoprotein quantitation in testicular cancer.

A sensitive flow cytometric assay has been developed using a monoclonal antibody, Myc 1-6E10, to quantitate c-myc oncoprotein levels in nuclei isolated from wax embedded testicular tumours. The oncoprotein (p62c-myc) level increased significantly with increasing teratoma differentiation. Patients with intermediate and undifferentiated tumours who developed recurrence had lower p62c-myc levels than those who were disease free since their initial treatment. Such quantitative biochemical methods may provide new prognostic indices for cancer patients.

Antibodies, Monoclonal↗
PubMed1984

The selection of monoclonal antibodies for tumour localization in patients with colorectal carcinoma.

We have investigated the ability of various predictive studies to assess which monoclonal antibody (MCA) will be most useful in the immunoscintigraphic localization of metastatic colorectal carcinoma. A set of MCAs was obtained by fusing splenic lymphocytes from rats immunized with membrane preparations from fresh human colorectal cancer. Supernatants from 17 cloned hybridomas were found to bind strongly to colon carcinoma lines by indirect radioimmunoassay. Immunofluorescence using these MCAs on sections of fresh frozen colon carcinoma and normal tissue revealed different staining patterns. Nine MCAs were purified and labelled with 131I. Groups of mice bearing human colorectal tumour xenografts were given radiolabelled MCA and scanned. Six out of the nine MCAs showed tumour localization as determined by rectilinear scanning. Three MCAs which gave good tumour images in mice were selected for clinical evaluation in patients with advanced colorectal cancer. One gave good tumour images, another targeted to bone marrow and the third bound almost exclusively to normal liver. Clinical evaluation is clearly essential in the selection of MCAs for tumour localization.

Animals↗
PubMed1984

Measurement of skin and total blood flow to the rabbit lower limb by washout of freely diffusible radioactive tracers introduced intra-arterially.

Good agreement was obtained when measuring total (capillary) blood flow in 9 rabbit thighs using two different techniques. The 133Xenon washout technique yielded a mean value of 8.0 cm3 X min-1 X 100 g tissue-1 whilst the microsphere technique gave a mean value of 7.8 cm3 X min-1 X 100 g tissue-1. There was a significant correlation (r = 0.83, p less than 0.006). In a further 14 rabbit thighs an attempt was made to measure skin blood flow by washout of 85Kr and to compare it with the microsphere technique. 133Xe promises to be a useful tracer for measuring lower limb flow when introduced intra-arterially. Because 85Kr tends to underestimate skin blood flow, and because of problems of diffusion of the tracer between compartments, which are discussed, this tracer is not satisfactory as a technique for measuring skin blood flow.

Animals↗
PubMed1983

Localisation of metastatic carcinoma by a radiolabelled monoclonal antibody.

Rat monoclonal antibodies were prepared by immunising rats with human colorectal carcinoma cell membranes and fusing splenic lymphocytes with a rat myeloma. Hybridoma supernatants were screened by binding assays on membranes prepared from colorectal carcinoma tissue. One hybridoma supernatant, containing a monoclonal antibody with high binding activity on malignant compared to normal colon sections, was grown in large quantities in serum-free medium. After ammonium sulphate precipitation the antibody was purified by ion-exchange chromatography and labelled with 131I. Radiolabelled antibody was administered i.v. to 27 patients with colonic and other tumours. Scintigrams were obtained at 48 h. Computerised subtraction of the blood pool image revealed localised areas of uptake corresponding with areas of known disease in 13/16 patients with colorectal carcinoma and 3/4 patients with breast cancer.

Adult↗