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Biomedical subjects

K James

Publications and source records attributed to K James.

At least 235 records · Page 13Linked to original sources
PubMed1983

Interactions of asbestos-activated macrophages with an experimental fibrosarcoma.

Supernatants from in vivo asbestos-activated macrophages failed to show any cytostatic activity against a syngeneic fibrosarcoma cell line in vitro. UICC chrysotile-induced peritoneal exudate cells also failed to demonstrate any growth inhibitory effect on the same cells in Winn assays of tumor growth. Mixing UICC crocidolite with inoculated tumor cells resulted in a dose-dependent inhibition of tumor growth; this could, however, be explained by a direct cytostatic effect on the tumor cells of high doses of crocidolite, which was observed in vitro.

5'-Nucleotidase↗
PubMed1983

Effects of C-reactive protein on human lymphocyte responsiveness.

C-reactive protein (CRP), a trace serum protein that increases markedly in concentration during inflammatory reactions, was recently shown to bind to a subset of human IgG-FcR-bearing peripheral blood lymphocytes in the presence of a ligand such as pneumococcal C-polysaccharide (CPS). CRP has also been detected on a small percentage of PBL that are associated with NK activity. In the present study, we assessed the effects of CRP and CRP-CPS complexes on a variety of human lymphocyte functions in vitro. CRP and CRP complexes significantly enhanced (generally two to threefold) cell-mediated cytotoxicity, minimally enhanced the MLC reaction, and induced a small but regularly detectable blastogenic response in resting PBL. CRP or CRP-CPS complexes had no effect on mitogen-induced blastogenesis, PWM-induced generation of IgM plaque-forming cells, E-rosette formation, antibody-dependent cell-mediated cytotoxicity, or NK activity. The basis for the preferential ability of CRP to enhance cytotoxicity responses in vitro is under further investigation.

Antibody-Dependent Cell Cytotoxicity↗
PubMed1983

The distribution and possible significance of cells identified in human lymphoid tissue by the monoclonal antibody HNK-1.

The monoclonal antibody HNK-1 identifies a subpopulation of lymphocytes containing almost all of the natural killer (NK) and antibody-dependent killer (K) cell activity. Using an immunoperoxidase technique on frozen tissue sections of human spleen, tonsil and lymph node we have demonstrated that cells identified by this antibody are almost exclusively confined to germinal centres. Comparison with the distribution of B cells, T cells and T cell subsets underlines the distinctive distribution of these cells for which a physiological role in the maturation of antibody affinity during immune responses is suggested.

Antibodies, Monoclonal↗
PubMed1983

C-reactive protein antigenicity on the surface of human lymphocytes.

We reported previously that C-reactive protein (CRP), when complexed to a multivalent binding specificity, can bind to a subset of lymphocytes that bear the IgG Fc receptor. Recently we showed that anti-CRP plus complement depletes natural killer function. We now show the detection of CRP on the surface (S-CRP) of a small percentage of PBL and on a minor population of phagocytic mononuclear cells. S-CRP is not detectable by direct immunofluorescence, but is readily discernible by using more sensitive techniques such as biotinylated anti-CRP with fluorescent avidin or indirect immunofluorescence with monoclonal anti-CRP. S-CRP is expressed in the absence of calcium, whereas the binding of complexed CRP is calcium dependent. S-CRP does not appear to be the exclusive binding site for CRP-CPS because anti-CRP does not block the binding of complexed CRP. Both the binding site for complexed CRP and S-CRP can be capped off; however, the kinetics of capping of these two surface molecules is different. Cells binding complexed CRP are OKT11-, whereas a significant number of PBL bearing S-CRP are OKT11+. Therefore cells bearing S-CRP appear to be a separate population from those that bind complexed CRP. These studies establish the presence of S-CRP on a subpopulation of lymphocytes, define conditions required for its detection, and speak to certain of the relationships between S-CRP and the binding site of CRP-CPS complexes.

Antibodies, Monoclonal↗
PubMed1983

Characterization of certain minor monodispersed bands found on serum protein electrophoresis as C-reactive protein.

A monodispersed band is a dense, homogeneous band on serum protein electrophoresis (SPE), indicating the presence of a discrete protein. Minor monodispersed bands in the gamma region on SPE usually indicate minor monoclonal immunoglobulins that can be characterized by immunofixation. Occasionally, these minor monodispersed bands cannot be shown to be immunoglobulins. This report illustrates that elevated levels of C-reactive protein (CRP) may be detectable as an "M-spike" on SPE; therefore, if immunofixation is performed, anti-CRP could be included in the panel of antisera used to characterize the minor monodispersed band. The detection of CRP as an "M-spike" in the gamma region is, however, dependent upon the absence of a chelating agent in the SPE support medium. When EDTA is present, the electrophoretic mobility of CRP is altered to a beta mobility.

Blood Protein Electrophoresis↗
PubMed1983

An introduction to tumour immunology.

In this brief review some of the basic concepts in tumour immunology are summarised. These include the nature of tumour antigens, the many and varied ways the immune system of the host may respond thereto, and the mechanisms by which tumours may evade such responses. The limitations of current immunotherapeutic procedures employed are also considered and potentially important areas of tumour immunology research are emphasized.

Antibodies, Monoclonal↗
PubMed1983

Progressive vaccinia associated with combined variable immunodeficiency.

Progressive vaccinia developed in a previously healthy woman following smallpox vaccination and was successfully treated with vaccinia immune human globulin and methisazone. Immunologic evaluation over the next 4 1/2 years revealed evidence for combined variable immunodeficiency with increased numbers of circulating OKT 8 positive (suppressor-cytotoxic T) cells and the virtual absence of OKT 4 positive (helper-inducer T) cells.

Female↗
PubMed1982

Distribution of fatty and fibrous plaques in young human coronary arteries.

We have correlated atheromatous plaque distribution with vessel geometry in coronary arteries from subjects dying of non-cardiovascular causes under 40 years of age. After standardised preparation, the area, and circumferential and longitudinal position of each plaque, were measured in the major coronary arteries. Of 41 sets of vessels, two were free of disease. In the remainder, total plaque area varied from 8 to 586 mm2. Half the cases showed fatty plaques only, and half showed both fatty and fibrous plaques. We analysed the distribution of plaques in those vessels affected only by very early fatty disease. In all vessels, plaques were concentrated proximally, but in the left anterior descending and circumflex branches the wall close to the flow-divider was spared. Circumferential distribution was also not random. In the right coronary artery, lesions were concentrated on the inner wall of the major curvature. In the left anterior descending branch, lesions spiralled anticlockwise from the orifice. We suggest that local mechanical factors may determine these patterns.

Adolescent↗
PubMed1982

Changes in serum acute phase proteins in breast cancer patients receiving methotrexate infusion therapy.

The serum concentrations of six glycoproteins (alpha 1-acid glycoprotein, AGP; haptoglobin, Hp; alpha 1-antitrypsin, AT; ceruloplasmin, Cp; prealbumin, PALB; and alpha 2-macroglobulin, MACRO) have been estimated serially in nine advanced breast cancer patients who received a total of 24 intravenous infusions of methotrexate (MTX). The serum glycoprotein levels taken before the first drug exposure did not relate with the prognosis of these patients. In eight patients, constantly high or rising levels of AGP, Hp and AT during consecutive infusions of the drug were associated with continued metastatic disease. A transient tumour regression occurred in one patient which correlated with falling serum levels of these proteins into the normal range. The serum levels of Cp, PALB and MACRO did not correlate with the clinical status of these patients during treatment. Possible factors which may influence the serum levels of these glycoproteins in cancer patients during therapy are discussed.

Aged↗
PubMed1982

Alpha 2-macroglobulin and proliferative retinopathy in type 1 diabetes.

Serum alpha 2-macroglobulin (alpha 2m) and total glycosylated haemoglobin (HbA1) concentrations were measured in 110 insulin dependent Type 1 diabetics with minimal or no fundoscopic retinopathy, referred to as non-retinopaths, and in 52 proliferative retinopaths. Proteinuria was recorded in 8 (7%) non-retinopaths and 29 (56%) retinopaths and was accompanied by elevated alpha 2m concentrations in both groups of diabetics but only significantly so in the non-retinopaths. Diabetics without proteinuria showed a significant correlation between alpha 2m concentration and duration of diabetes, HbA1 and age (being higher at extremes of age). Alpha 2m concentrations were significantly higher in retinopaths than in non-retinopaths without proteinuria when allowance was made for the influence of age and duration of diabetes on alpha 2m. This difference may be attributed to the higher HbA, levels found in retinopaths than in non-retinopaths and was no longer evident when account was taken of the prevailing HbA1 concentration in individual patients.

Adult↗
PubMed1982

A modified radio-immune antiglobulin test for the screening of anti-red blood cell antibodies in hybridoma supernatants.

A radio-immune antiglobulin test was developed using mouse monoclonal anti-human A red blood cell (RBC) antibodies, and applied to the screening and study of hybridoma supernatants containing anti-human RBC antibodies. The latter antibodies were provided either as known monoclonal antibodies from culture supernatants and ascitic fluids, or as culture supernatants to be screened. The technical feasibility of the test was greatly facilitated by the use of remova-well disposable polystyrene plates, multichannel pipettes, and multiple-plate centrifuge holders. The sensitivity of the test and its relevance for the screening of hybridoma anti-human RBC antibodies is discussed.

Animals↗
PubMed1982

Interactions of C-reactive protein with lymphoid cells.

The interactions between CRP and peripheral blood lymphocytes were investigated. CRP, in the presence of an appropriate ligand, bound saturably to a small percentage of normal PBL. The characteristics and optimal conditions for this binding were defined using several different assay systems. CRP was found to bind preferentially to cells with the IgG FcR. Binding was increased in the presence of acute phase sera, and higher numbers of cells binding CRP were observed in acute phase individuals. CRP and CRP-CPS had minimal effects upon lymphocyte responsiveness in vitro, although enhancing effects on MLC and CMC reactions, and a slight blastogenic effect, were observed. CRP antigenicity was detected on a small percentage of PBL, and treatment of PBL with anti-CRP and complement led to loss of NK reactivity, suggesting a possible association of CRP with this function. The functional expression of binding of CRP complexes, the relationship of the CRP-binding site to surface CRP antigenicity and the FcR, and the role of these factors in lymphocyte functions such as NK reactivity and recognition, are yet to be determined.

Animals↗
PubMed1982

Complement: activation, consequences, and control.

The activation of complement provides the humoral (fluid-phase) effector mechanism most responsible for immune-mediated injury. The classical pathway is activated by an antigen-antibody reaction. The binding of C1q initiates the sequential activation of the eleven proteins. The classical pathway has a calcium-dependent step (C1q, C1r, C1s) and a magnesium-dependent reaction (the enzymatic action of C1s on C4 and C2). The alternative pathway appears to be spontaneously activated, but the perpetuation of that activation is dependent upon the availability of an activating (or protective) surface which interferes with the inactivation of C3b by control proteins. The alternative pathway has a magnesium-dependent step, the binding of B to C3b to form the C3 convertase. Once initiated, the alternative pathway activation results in the sequential activation of nine proteins, six of which are common to both pathways. The activation of complement results in a variety of biologic consequences which can result in injury to the host. The potential destructiveness of the effects of complement activation is modulated by a series of control proteins.

Carrier Proteins↗