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C W Reynolds

Publications and source records attributed to C W Reynolds.

At least 73 records · Page 4Linked to original sources
PubMed1984

Purification and properties of cytoplasmic granules from cytotoxic rat LGL tumors.

To evaluate the role of NK cell granules in the lytic activity of NK cells, cytoplasmic granules of rat NK tumors were purified by centrifugation of the cell homogenates in a Percoll gradient. Analysis of such gradients showed a band of light-scattering material near the bottom of the tube; assay of gradient fractions for lytic activity against SRBC showed a potent lytic activity giving a sharp peak in this region. Complete lysis of SRBC was achieved with less than 1 microgram/ml protein of the most active fractions. Examination in the electron microscope showed that a pool of fractions containing lytic activity consisted of pure cytoplasmic granules showing similar morphology to those found in the LGL tumors. The lytic band was associated with a peak in the activity of four different lysosomal enzymes. Analysis of Percoll gradient fractions showed that marker enzymes for mitochondria, plasma membrane, and cytosol were well separated from this activity peak. Analysis of the Percoll gradient fractions by SDS gel electrophoresis showed that this granule fraction was free of contamination of proteins from other parts of the gradient. The granules contained major protein bands of 62, 58, 30, 29, and 28 kilodaltons. In addition to protein, the purified granule fractions contain hexose and uronic acid, but no nucleic acids or phospholipids were detected in chemical assays. Major amounts of chymotryptic, tryptic, and elastase activities were not present, nor were peroxidase or lysozyme activities detectable in substantial amounts. These data show that NK tumor cell cytoplasmic granules contain a potent lytic activity and have biochemical properties that distinguish them from granules present in granulocytes and mast cells.

Animals↗
PubMed1983

Immunoperoxidase localization of large granular lymphocytes in normal tissues and lesions of athymic nude rats.

The immunocytochemical localization of cells reacting with the OX-8 monoclonal antibody was studied in athymic nude rats by the avidin-biotin-peroxidase complex (ABC) immunoperoxidase technique. By a number of criteria, including morphology and tissue distribution of OX-8-positive cells, it is postulated that the majority of lymphocytes reacting with OX-8 antibody in nude rats are LGL. The cell surface of large lymphocytes reacted with the OX-8 antibody in fixed tissue sections. The tissues with the greatest density and percentages of these reactive cells included the paracortex of lymph nodes in association with interdigitating cell (IDC) hyperplasia, bronchial-associated lymphoid tissue (BALT), the medullary cords and sinuses of lymph nodes, and intestinal epithelium. Ultrastructure of the paracortical areas of IDC hyperplasia revealed granular lymphocytes in close association with IDC. Tissues with the fewest positive cells included bone marrow, B cell areas of lymphoid tissues, and parenchymal epithelial organs. In healthy and cachectic nude rats, various incidental and pathologic lesions contained a significant number of OX-8-positive cells. Large numbers of positive lymphocytes were seen in suppurative pneumonic lesions, enteritis, focal ulcerative epithelial lesions, and papovaviral sialoadenitis. The observation of a large number of OX-8-positive lymphocytes in nonlymphoid organs supports the hypothesis that these cells play a major role in the first line of defense against not only tumors but also infectious agents.

Animals↗
PubMed1983

Distribution of peritoneal macrophage populations after intravenous injection in mice: differential effects of eliciting and activating agents.

Murine peritoneal macrophages (pM phi) elicited in vivo by intraperitoneal (IP) inoculation of various agents were tested for their homing/distribution patterns after intravenous (IV) adoptive transfer to syngeneic C57BL/6 recipients. Resident pM phi (RpM phi) obtained from normal mice and pM phi elicited by proteose peptone (PpM phi) or thioglycollate broth (TpM phi) exhibited similar homing patterns following IV transfer. After initial arrest in the lungs, these cells rapidly disseminated to liver and spleen, with minimal or no detectable migration to peripheral lymph nodes, intestine, peritoneum, kidney, heart, or retention in the blood. The pattern of results reflected the properties of pM phi themselves, since highly enriched pM phi populations obtained by treatment of crude peritoneal exudate cells with anti-Thy 1.2 + C, or by fractionation on Percoll density gradients, gave similar results. The distribution of pM phi elicited by Brewer's thioglycollate medium (BTpM phi) was markedly different from other pM phi tested. BTpM phi homed rapidly to the lungs and many remained localized there for at least 72 hr with very little migration to the spleen. The distribution of PpM phi could be altered by activation of these cells in vivo through the IP injection of the pyran copolymer, MVE-2, prior to adoptive IV transfer. Activated PpM phi contained a population of highly differentiated, low density pM phi, separable on density gradients, which arrested in the lungs for appreciably longer periods of time than did PpM phi. These cells exhibited reduced ability for migration to the spleen. Macrophage-like (M phi-like) cell lines did not exhibit migration capability, but rather were rapidly cleared from the circulation in a manner similar to other types of tumor cells.

Animals↗
PubMed1983

Large granular lymphocyte leukemia. A heterogeneous lymphocytic leukemia in F344 rats.

The morphology, histochemistry, cell surface antigens, and natural killer cell (NK) activity of 10 primary and 10 transplantable large granular lymphocyte (LGL) leukemias of aging F344 rats were studied. The LGL leukemia is the major cause of death of aging F344 rats. Morphologically, the LGL leukemias were composed of cells with either pleomorphic nuclei with many intracytoplasmic granules or round nuclei with few intracytoplasmic granules. The granules appeared to be lysosomes containing beta-glucuronidase and acid phosphatase and ultrastructurally developed in association with vesicles in the Golgi apparatus. Splenic natural killer cell activity against YAC-1 cells varied from case to case, and it appeared to be associated with LGL leukemia cells. Some transplantable leukemias had stable NK activity. Fluorescence-activated cell sorter (FACS) analysis of surface antigens revealed the LGL leukemias to be heterogeneous, and there was no correlation between cytotoxic activity and cell surface antigens. Although the morphologic features of cells in LGL leukemias resemble those of normal rat LGLs, differences in cytotoxic activity and surface antigens suggest that LGL tumors represent a heterogeneous group of leukemias which may serve as a model for the study of origin and lineage of normal LGL and NK cells.

Aging↗
PubMed1983

In vivo role of natural killer cells: involvement of large granular lymphocytes in the clearance of tumor cells in anti-asialo GM1-treated rats.

The present study was performed to further evaluate the possible in vivo involvement of natural killer (NK) cells in host resistance against tumors. Selective depression of NK activity in Wistar Furth rats was induced by i.p. or i.v. injection of rabbit anti-asialo GM1. This antiserum has previously been shown to produce a decrease in NK activity and a parallel increase in tumor growth in mice. In the present study, rats treated with this antibody showed a parallel decrease in NK activity and in the frequency of large granular lymphocytes (LGL) in the spleen and peripheral blood, indicating that the antiserum-induced depression of NK activity in these sites was probably caused by an elimination of most effector cells. To further determine the possible role of rat LGL in tumor rejection in vivo, we studied LGL involvement in the rapid clearance of radiolabeled tumor cells from the lungs, an assay previously shown to correlate well with in vitro NK activity. Animals treated with anti-asialo GM1 antiserum were found to have a substantial decrease in the in vivo rate of clearance of tumor cells from the lungs. Furthermore, the adoptive transfer of a highly enriched population of LGL into NK-depressed animals 2 hr before tumor challenge, partially restored their cytotoxic activity against established cell lines in vitro and their ability to eliminate radiolabeled cells from the lungs. These results provide direct support for the hypothesis that NK cells are involved in in vivo resistance to tumors, particularly in the elimination of potentially metastatic tumor cells from the circulation and capillary beds.

Animals↗
PubMed1983

Rat natural killer cell activity against lymphoid and nonlymphoid tumor cells and normal rat cell lines.

Natural cytotoxicity in the rat was assessed against solid tumors and normal and embryonic rat monolayer culture lines, and the results were compared with rat natural killer activity towards syngeneic, allogeneic, and xenogeneic lymphoma targets. The targets tested showed a very wide range of susceptibility to lysis by peripheral blood and spleen effector cells in both 4- and 18-hr cytotoxicity assays. Cytotoxicity toward the mouse lymphoma, YAC-1, and rat sarcoma LT1 targets was relatively high in a 4-hr assay, compared with that toward the other cell lines used in the study. At 18 hr, increased killing was seen against YAC-1, LT1, SP3 (rat pheochromoblastoma), F2304 (rat embryonic cells), and normal rat kidney cells, while a significant increase in susceptibility with time was not observed with other rat targets: W/Fu-T (sarcoma); ERTh/V-G (sarcoma); R35 (mammary tumor); and W/Fu-P21 (embryo fibroblasts) targets. The cytotoxicity against all of the targets tested was not age restricted and was potentiated by rat interferon. Natural cytotoxic reactivity was seen with effector cells from the blood, spleen, and peritoneal cavity of both W/Fu (euthymic) and Rowett nude (congenitally athymic) rats. Cytotoxic effector cells from the blood were present in the low-density fractions recovered from discontinuous Percoll density gradients and, as shown previously for lymphoma target cells, a strong correlation was observed between the killing of embryonic, normal, and solid tumor targets and the presence of large granular lymphocytes. These results indicate that the naturally cytotoxic rat effector cells for normal fibroblast and bone marrow targets, lymphomas-leukemias, embryonic cell lines, and solid tumor targets are all included in the large granular lymphocyte subpopulation.

Aging↗
PubMed1982

Natural killer cell activity in the rat. Analysis of effector cell morphology and effects of interferon on natural killer cell function in the athymic (nude) rat.

Athymic (nude) rats were found to have increased levels of natural killer (NK) activity, 3- to 5-fold higher than in euthymic rats. Studies were performed to determine the nature of the NK cells in these animals and the basis for their increased cytotoxic reactivity. Large granular lymphocytes (LGL), which were previously shown to be the NK cells in euthymic rats, were increased 2- to 7-fold in the peripheral blood and spleen of nude rats. The LGL, enriched by centrifugation on discontinuous Percoll density gradients, were shown to have augmented NK activity similar to that seen with LGL-enriched fractions from euthymic rats. These results indicate that the NK cells in euthymic and athymic rats are morphologically and functionally similar, and that the higher NK activity in nude rats appears to be mainly attributable to an increased proportion of effector cells. In a single-cell cytotoxicity assay, interferon pretreatment of LGL was shown to increase: (a) the percentage of LGL which form conjugates with target cells; (b) the percentage of conjugate-forming cells which kill; and (c) the kinetics of lysis. Different effects were seen depending on the target cell tested.

Animals↗
PubMed1982

Isolation of human and rat natural killer cells.

We describe a method for the purification of human and rat large granular lymphocytes (LGL), which are known to be the mediators of natural killer (NK) activity in these species. Plastic non-adherent and nylon wool passed blood mononuclear cells were separated into 7 fractions by discontinuous density gradient centrifugation on Percoll. Low density cells were highly enriched in LGL (up to 85% purity), whereas high density cells were typical small and medium sized lymphocytes devoid of NK activity. Human LGL could further be enriched by depleting high affinity sheep erythrocyte rosette-forming cells from the LGL-enriched Percoll fractions (resulting in up to greater than 90% purity). One critical variable in the separation technique was osmolarity, since the separation did not work optimally, if 290 mOsmoles/kg H2O in the Percoll solution was exceeded.

Animals↗
PubMed1981

Immunologic aspects of the prostate.

Our experiments involving the use of the Dunning R3327 adenocarcinoma as an animal model of prostatic cancer as well as clinical studies on the immunocompetence of prostatic cancer patients are described. Utilizing the Dunning tumor, we have demonstrated that this transplantable adenocarcinoma of the rat prostate was similar to human prostatic cancer with respect to its macroscopic and microscopic appearances, growth rate, growth differential in male and female recipients, and some of its metastatic potential. Cryosurgery was capable of destroying the primary tumor as it can in man. Both antibody and cellular immune responses could be produced against antigens associated with the tumor cells. Tumor-bearing rats treated by cryosurgery in combination with BCG were capable of producing an antitumor immunity that protected them from rechallenge. Clinical studies of prostatic cancer patients showed a diminished in vitro immunity, but the responses of the cancer patients were not significantly different from those of patients with benign prostatic disease.

Adenocarcinoma↗
PubMed1981

Role of macrophage in in vitro augmentation of rat, mouse, and human natural killer activities.

Requirement for macrophages in in vitro augmentation, by interferon (IFN), polyinosinic-polycytidylic acid (poly I:C), or Corynebacterium parvum, of rat, mouse, and human natural killer (NK) activities was examined. Several differences were seen among the species. Mouse NK activity demonstrated some lability at 37 degrees C and a strict macrophage requirement for in vitro production of IFN, and augmentation of NK activity was demonstrated by either poly I:C or C. parvum. In contrast, human peripheral blood leukocytes (PBL) depleted of monocytes by adherence on nylon wool demonstrated NK activity, which was not labile but rather increased substantially upon overnight culture at 37 degrees C alone or with poly I:C or C. parvum. Monocyte-depleted human PBL also produced IFN in these cultures. The pattern of reactivity seen with rat spleen cell cultures was different from either that of mouse and human cells. This pattern of reactivity had no lability at 37 degrees C and had a macrophage requirement for IFN production and NK cell augmentation upon culture alone or with poly I:C but not with C. parvum. These results indicated some major differences among species in the regulation of NK activity in vitro and the requirement for macrophages for the in vitro production of IFN. A better understanding of these differences will be helpful in choosing appropriate models for in vitro and in vivo studies of NK cell activity.

Animals↗
PubMed1981

In vitro augmentation of rat natural killer (NK) cell activity.

In vitro augmentation of rat natural killer (NK) cell activity was produced by 2 types of treatment. Increased activity occurred "spontaneously" when spleen cells were cultured alone at 37 degrees C. This augmentation was dependent on the presence of adherent, phagocytic cells, presumably macrophages, and was independent of LPS of FCS. Normally low levels of NK activity, present in macrophage-depleted cultured cells, could also be boosted in vitro by incubation with Corynebacterium parvum. This augmentation appeared to be independent of both B cells and macrophages and may be due to stimulation of rat NK cells themselves. Both forms of augmentation were associated with the production of interferon, were found in rats of all ages and strains tested, and should provide an excellent in vitro system for detailed studies of activation of rat NK cells.

Aging↗
PubMed1981

Natural killer activity in the rat. II. Analysis of surface antigens on LGL by flow cytometry.

With the use of monoclonal antibodies and continuous flow microfluorometry, we have examined the cell surface antigenic characteristic of rat large granular lymphocytes (LGL) and compared them with monocytes, T cells, and polymorphonuclear leukocytes (PMN). The antigenic profile of rat LGL was of particular interest because these cells have been shown to be highly associated with natural killer (NK) activity. This analysis of enriched populations demonstrated that rat LGL are in antigenically distinct population of cells that share some characteristics with monocytes, T cells, and PMN. Essentially all of the cells in the enriched LGL population expressed with W3/13, OX-8, leukocyte-common (L-C), and asialo GM1 antigens. A portion of these cells were also positive with a monoclonal Ab against the ART-1a antigen. In contrast, few LGL expressed the Ia, W3/25, surface immunoglobulin (sIg), or Thy 1.1 antigens. Monocytes demonstrated a pattern of reactivity similar to LGL but were found to by OX-8 negative. As previously reported, a portion of the T cells were found to express ART-1a, W3/25, and/or OX-8. These results demonstrate that rat LGL are not typical T cells, B cells, monocytes, or PMN. However, the sharing of antigenic markers by LGL with some T cells and monocytes raises the possibility that LGL may be in the development lineage of 1 of these populations.

Animals↗
PubMed1981

Natural killer (NK) cell activity in the rat. I. Isolation and characterization of the effector cells.

This study has demonstrated the presence of large granular lymphocytes (LGL) in the rat and implicated a central role for these cells in mediating natural killer (NK) cell activity in this species. The LGL frequency from various organs was shown to be: peripheral blood = lung greater than spleen greater than peritoneal exudate greater than lymph node. Little or no LGL were found in the thymus or bone marrow. This pattern was similar to the distribution of NK activity, except for the lungs, which had no detectable activity. These studies have also shown that discontinuous Percoll density gradients can be used to highly enrich or deplete LGL from both spleen and peripheral blood. Enriched LGL populations were shown to bind selectively to NK-susceptible target cells and to demonstrate very high NK cell cytolysis. Since human NK activity has also been found to be clearly associated with LGL, the present findings indicate that rats may provide a very useful animal model for detailed studies of the ontogeny, regulation, and in vivo relevance of NK cells.

Animals↗
PubMed1980

The Dunning tumors.

We have described the Dunning tumor, R3327, as a most useful model system in studies of human prostatic cancer. The tumor resembles the human disease in its histologic picture, ultrastructure, and most of its metastatic capabilities. The one exception to the latter is the apparent absence of metastatic lesions in the bone. Like the variability seen in human cancer of the prostate, the R3327 has been shown to develop multiple sublines, each with different histologic pictures, growth rate, and androgen dependence. Thus far the literature is replete with reports of the Dunning tumor as a model in hormonal, chemotherapeutic, and immunologic experiments. When we look at the results obtained in the five years since the Dunning tumor has been resurrected, we can be encouraged with what the future of prostatic cancer research holds with the use of this system.

Adenocarcinoma↗
PubMed1978

An animal model for the study of prostate carcinoma.

We report here the development of the Dunning R-3327 prostate adenocarcinoma of the Copenhagen rat as a suitable model of human prostate cancer. Tumors, produced by sc or intraprostate injection of viable cells, had the macroscopic and microscopic characteristics of the human disease. The histologic picture of these tumors was of a well-differentiated adenocarcinoma with the formation of glands and acid secretions within the acini. The intraprostate tumor, although initially confined to the injected lobe, grew to involve the surrounding tissues and eventually metastasized to the lymph nodes and lungs. Occasional metastatic lesions were found in other organs as well. During investigation of the tumor, a fast-growing line arose that grew equally well in females as in males. The histology of this tumor was of an undifferentiated anaplastic tumor. A tissue culture line derived from R-3327 was capable of producing tumors in recipient rats with characteristics similar to the original Dunning tumor.

Adenocarcinoma↗
PubMed1978

Immunologic studies of prostatic cancer using the R3327 rat model.

We report herein on the destruction by cryosurgery of the Dunning R3327 adenocarcinoma grown in the prostate. Tumors less than 1,000 mm.3 were destroyed by a single freezing procedure within 2 to 4 weeks, whereas tumors greater than 1,000 mm.3 could not be destroyed completely. We also have been able to demonstrate antibody and cellular immune responses to antigens on the R3327 cells. Species, organ and tumor specific antigens were identified by xenogeneic antiserum produced in the rabbit, while major and minor antigens were identified by alloantisera produced in the rat. Tumor antigens were characterized by a variety of in vitro and in vivo immune responses. In addition to the rabbit xenoantisera used in cytotoxicity assays, mixed lymphocyte tumor interaction produced a demonstrable in vitro immune response, lymphocytes from rats immunized with tumor cells were cytotoxic to radiolabeled tumor cells in culture, rats immunized with tumor cells in adjuvant demonstrated protection against subsequent challenge and immunological stimulation of lymph nodes draining the site of tumor cell inoculation was demonstrated by an increase in lymphocyte trapping. Clearing, the R3327 tumor system in the rat is suitable for immunological studies of prostatic cancer.

Adenocarcinoma↗