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N Kraft

Publications and source records attributed to N Kraft.

At least 37 records · Page 2Linked to original sources
PubMed1984

The use of immunohistochemical probes in the study of benign and malignant breast disease.

A review is presented of the use of immunohistochemical probes in the study of the cellular pathology of the breast. Using a combination of monoclonal and polyclonal antisera it has been possible to investigate the relationship between myoepithelial cells and basement membrane components in benign breast disease and the disturbance of this relationship in early invasive and infiltrating ductal carcinomas. The use of immunohistochemical techniques at the ultrastructural level provides the methodology for future detailed analyses. The heterogeneous expression of antigenic determinants characteristic of epithelial cells in the normal breast is considered in conjunction with its relevance to the heterogeneity seen in the invasive tumours.

Animals↗
PubMed1984

Monoclonal antibody analysis of glomerular hypercellularity in human glomerulonephritis.

To determine the contribution of infiltrating circulating leucocytes to glomerular hypercellularity, and to further investigate the immune and inflammatory mechanisms involved in human glomerulonephritis, a series of renal biopsies were evaluated using cell-specific monoclonal antibodies. In ninety-three renal biopsies from patients with glomerulonephritis, intraglomerular leucocytes were identified by immunoperoxidase localization of monoclonal antibodies to the leucocyte-common antigen, and antigens characteristic of T-cell and T-cell subsets, B-cells, monocytes and granulocytes. Normal glomeruli contained a mean of 2 leucocytes, predominantly monocytes, per glomerular cross-section. No significant increase in leucocytes was found in 41 biopsies with non-proliferative types of glomerulonephritis. However, in renal biopsies from 22 of the 46 patients with proliferative forms of glomerulonephritis, there was a significant increase in glomerular leucocytes. These biopsies were from 5 patients with post-infectious glomerulonephritis (mean of 30 leucocytes per glomerulus), 11 patients with crescentic glomerulonephritis (mean of 16 leucocytes per glomerulus) and 6 patients with mesangial proliferative glomerulonephritis due to systemic lupus erythematosus (mean of 5 leucocytes per glomerulus). The increased intraglomerular leucocytes consisted of macrophages and granulocytes. T and B-cells were generally not found within glomeruli. Thus, glomerular hypercellularity in proliferative glomerulonephritis is in part due to infiltration by inflammatory cells. No evidence was found to directly incriminate cellular immune mechanisms in the pathogenesis of the glomerular lesions of glomerulonephritis since T-cells were not identified within glomeruli.

Antibodies, Monoclonal↗
PubMed1984

Invading squamous cell carcinoma can retain a basal lamina. An immunohistochemical study using a monoclonal antibody to type IV collagen.

A monoclonal antibody to human glomerular type IV collagen has been characterized and used in an immunohistochemical study of the distribution of this basement membrane protein in dysplasias, intraepithelial carcinomas, and infiltrating squamous cell carcinomas. Four squamous carcinoma cell lines established as xenografts in nude mice were also examined. In normal epidermis and mucosae, the basement membrane was clearly defined and intact. In areas of intraepidermal carcinoma, the basal lamina as defined by the antibody was usually continuous, and defects were only present in areas associated with an inflammatory infiltrate. Invasive squamous cell carcinomas, regardless of the degree of differentiation had a clearly delineated basement membrane at the epithelial stromal interphase. In areas of invasion, far removed from the in situ component, there were protrusions of tumor cells through the basement membrane into the stroma. Other abnormalities of basement membrane production such as aggregation of basement membrane and reduplication of the basal lamina were also associated with the carcinomas. There was a similar distribution of basal lamina material in involved lymph nodes and in squamous cell carcinomas that were growing as xenografts in nude mice. Our studies suggest that the loss of basement membrane type IV collagen is not generally associated with invasive squamous cell carcinomas and is not likely to be useful in the assessment of early invasion in this tumor. The similar distribution of type IV collagen in the xenografts and in the infiltrating tumors suggests that this system, in conjunction with the use of the same cell lines in vitro, will provide a model with which to study the control of deposition of type IV collagen.

Antibodies, Monoclonal↗
PubMed1982

Cell lines derived from a human myelomonocytic leukaemia.

Two cell lines have been isolated from separate samples, taken at the same time, from the peripheral blood of a case of myelomonocytic leukaemia. One of these (CESS-B) is a typical B cell line obtained after treatment of the peripheral blood white cells with Epstein-Barr virus (EBV). The second line (RC-2) is a monocyte-macrophage type, originally isolated by 5 months continuous culture in the presence of colony stimulating factor (CSF). Subsequently, after further culture, this line has become autonomous (RC-2A), no longer requiring CSF for maintenance of proliferation, whilst retaining the characteristics of the original line.

Adult↗
PubMed1982

The immunohistochemical demonstration of major histocompatibility antigens in the human kidney using monoclonal antibodies.

The distribution of HLA-ABC and DR antigens in human kidneys was studied using monoclonal antibodies to monomorphic determinants and a 4-layer immunoperoxidase technique applied to frozen and paraffin sections. Enzyme digested paraffin sections provided the best localization. HLA-ABC antigens were located on all renal endothelium, Bowman's capsule and in proximal tubules. HLA-DR antigen was restricted to capillary and venous endothelium plus, at low density, in proximal tubules. Minor differences in distribution were found with different monoclonal antibodies, but dendritic cells were not detected using monoclonal antibodies to HLA-ABC, HLA-DR or leukocyte-common antigens.

Antibodies, Monoclonal↗
PubMed1981

Monoclonal antibodies to human macrophage and leucocyte common antigens.

Three monoclonal antibodies have been made to identify cells of the human mononuclear phagocyte system in fluids and tissues. The first, PHM 1, recognises a surface antigen common to all leucocytes. The other 2 antibodies, PHM 2 and PHM 3, bind to monocytes and macrophages but not to polymorphonuclear cells (PMN). PHM 2 labels all monocytes, macrophages and a small population of T-cells. PHM 3 labels most monocytes and macrophages but no other blood cells. The application of these monoclonal antibodies to the identification of mononuclear phagocytes in blood and liver using an unlabelled antibody immunoperoxidase (PAP) technique is demonstrated.

Antibodies, Monoclonal↗
PubMed1979

Modulation of inhibition of the human mitogen response by methylprednisolone.

The in vitro response of human lymphocytes to phytohaemagglutinin was inhibited in a dose-related fashion by methylprednisolone added to the cell culture. The inhibition by steroid was 100-fold less than expected from published values of human lymphocyte receptor affinity. The dose response curve for inhibition was complex, frequently featuring a plateau region suggestive of a heterogeneous system, possibly caused by the presence of more than one subpopulation of cells. When lymphocytes were separated by unit velocity sedimentation, slow sedimenting lymphocytes were found to be highly steroid sensitive whereas rapidly sedimenting lymphocytes were steroid resistant. However, the addition of cultured macrophages rendered the steroid-sensitive fractions relatively steroid resistant. Similarly, unseparated peripheral blood lymphocytes at low concentrations were found to be highly steroid sensitive despite the addition of 2-mercaptoethanol. This sensitivity was lost by the addition of culture macrophages. Thus, macrophages play a vital role in the relative steroid resistance of human lymphocytes. No evidence was found that macrophages actually reduced steroid concentration in culture, and it is suggested that a cellular interaction is required to increase resistance to steroids.

Dose-Response Relationship, Drug↗
PubMed1979

The binding of ouabain to normal and chronic lymphocytic leukemic lymphocytes.

The binding of the cardiac glycoside, ouabain, to cells had been used to quantify the number of active cation pumps. In this study, lymphocytes were incubated with 3H-ouabain and the equilibrium binding analyzed for the maximal number of specific binding sites. Lymphocytes from normal peripheral blood bound 44,200 +/- 9920 molecules/cell, compared with 29,200 +/- 8370 molecules/cell for the lymphocytes of chronic lymphocytic leukemia (CLL) subjects. This difference was significant (p less than 0.01) and did not reflect a lower number of sites on B cells than T cells, since B-cell-enriched lymphocytes from normal peripheral blood showed the same ouabain binding characteristics as the standard T-cell-rich preparation. Although monocytes bind threefold more ouabain than lymphocytes, the small monocyte contamination (3.0%) in normal lymphocyte preparations could not account for the difference between normal and CLL. The fewer ouabain binding sites on CLL lymphocytes may reflect both their smaller size (by 10%) and lower mitotic activity compared with lymphocytes from normal peripheral blood.

B-Lymphocytes↗
PubMed1978

67Ga and 59Fe uptakes by cultured human lymphoblasts and lymphocytes.

Studies with spontaneously proliferating human lymphoblastoid cells have shown that cellular uptake of both 67Ga and 59Fe3+ (as citrates) become appreciably increased with small additions of purified human transferrin to the cultures. In many respects, their uptake responses were broadly similar to those previously reported for cultured mouse lymphoid tumor cells. Studies were also undertaken with cultured human lymphocytes, but transferrin promotion of tracer uptakes could not be detected for these cells. In addition, cellular uptakes for phytochemagglutinin-stimulated cultures were not significantly increased over their unstimulated controls.

Cells, Cultured↗
PubMed1976

Antigen recognition. IV. Discrimination by antigen-binding immunocompetent B cells between immunity and tolerance is determined by adherent cells.

Mouse spleen cells capable of specifically binding intrinsically tritium-labeled polymerized flagellin (POL) (labeling by biosynthesis of flagellar protein) via IgM receptors were found to comprise a distinct population of about 20-50 cells per 10(6) lymphocytes. Evidence is presented that the majority of mouse spleen cells binding tritium-labeled POL undergoes blastogenesis after antigen capping, antigen shedding, and receptor reformation. Under conditions of tolerance induction in vitro, however, loss of antigen from the cell surface was inhibited. Such inhibition of antigen redistribution and shedding was reversed by a short pulse of colchicine and new antigen receptors were formed. In spite of this, colchicine had no effect on the tolerant state. However, tolerance could be broken, regardless of presence or absence of the alkaloid, with radioresistant theta-negative accessory (A) cells (adherent cells) from normal but not from tolerant spleen cell populations. "Tolerant" A cells, although they were incapable of cooperating in a response to POL, were capable of participating in a response to a second unrelated antigen. It is concluded that tolerance to POL in vitro is induced by mechanisms other than the physical blocking of bone marrow-derived (B) cell receptors by antigen. Most likely, the discrimination by the B cell between a tolerogenic and immunogenic signal is mediated by A cells.

Animals↗