Immunomagnetic t-lymphocyte depletion (ITLD) of rat bone marrow using OX-19 monoclonal antibody

Graft versus host disease (GVHD) may be abrogated and host survival prolonged by in vitro depletion of T lymphocytes from bone marrow (BM) prior to allotransplantation. Using a mouse anti-rat pan T-lymphocyte monoclonal antibody (0×19) bound to monosized, magnetic, polymer beads, T lymphocytes were removed in vitro from normal bone marrow. The removal of the T lymphocytes was confirmed by flow cytometry. Injection of the T-lymphocyte-depleted bone marrow into fully allogeneic rats prevents the induction of GVHD and prolongs host survival. A highly efficient technique of T-lymphocyte depletion using rat bone marrow is described. It involves the binding of OX-19, a MoAb directed against all rat thy-mocytes and mature peripheral T lymphocytes, to monosized, magnetic polymer spheres. Magnetic separation of T lymphocytes after mixing the allogeneic bone marrow with the bead/OX-19 complex provides for a simple, rapid depletion of T lymphocytes from the bone marrow. In vitro studies using flow cytometry and the prevention of GVHD in a fully allogeneic rat bone marrow model have been used to demonstrate the effectiveness of the depletion procedure. © 1989 Informa UK Ltd All rights reserved: reproduction in whole or part not permitted

DNA vaccination for prostate cancer: key concepts and considerations

While locally confined prostate cancer is associated with a low five year mortality rate, advanced or metastatic disease remains a major challenge for healthcare professionals to treat and is usually terminal. As such, there is a need for the development of new, efficacious therapies for prostate cancer. Immunotherapy represents a promising approach where the host’s immune system is harnessed to mount an anti-tumour effect, and the licensing of the first prostate cancer specific immunotherapy in 2010 has opened the door for other immunotherapies to gain regulatory approval. Among these strategies DNA vaccines are an attractive option in terms of their ability to elicit a highly specific, potent and wide-sweeping immune response. Several DNA vaccines have been tested for prostate cancer and while they have demonstrated a good safety profile they have faced problems with low efficacy and immunogenicity compared to other immunotherapeutic approaches. This review focuses on the positive aspects of DNA vaccines for prostate cancer that have been assessed in preclinical and clinical trials thus far and examines the key considerations that must be employed to improve the efficacy and immunogenicity of these vaccines

Dunning rat prostate adenocarcinomas and alternative splicing reporters: powerful tools to study epithelial plasticity in prostate tumors in vivo

Using alternative splicing reporters we have previously observed mesenchymal epithelial transitions in Dunning AT3 rat prostate tumors. We demonstrate here that the Dunning DT and AT3 cells, which express epithelial and mesenchymal markers, respectively, represent an excellent model to study epithelial transitions since these cells recapitulate gene expression profiles observed during human prostate cancer progression. In this manuscript we also present the development of two new tools to study the epithelial transitions by imaging alternative splicing decisions: a bichromatic fluorescence reporter to evaluate epithelial transitions in culture and in vivo, and a luciferase reporter to visualize the distribution of mesenchymal epithelial transitions in vivo

Survival of human prostate carcinoma, benign hyperplastic prostate tissues, and IL-2-activated lymphocytes in scid mice.

Mice, homozygous for the mutation severe combined immunodeficiency (scid) and also segregating for the mutation hypogonadal (hpg), were tested for their potential use as an in vivo model system for studying the growth of human prostate cancer and benign hyperplastic prostate tissue grafts. Fresh human prostate cancer or benign hyperplastic prostate tissue was implanted subcutaneously into androgen-replete C.B. 17 scid/scid males, and into androgen-deficient hpg/hpg scid/scid or androgen-replete +/? scid scid males. The tissue grafts grew in both androgen-replete and androgen-deficient host mice. When dihydrotestosterone (DHT) was administered at tissue grafting, both the incidence and size of the tissue grafts increased. Histology of tissue from tumors in the androgen-deficient hpg/hpg scid/scid host showed either undifferentiated tumors or adenocarcinomas with few glandular structures. These data suggest the androgen deficient environment selected for growth of androgen-independent tumor tissue. Finally, when interleukin-2 (IL-2)-activated tumor-infiltrating lymphocytes were injected into scid/scid hosts, the cells were found to survive and could be identified in the spleen of the recipient mice. These results indicate that growth of human prostate tissues and IL-2-activated lymphocytes in scid/scid mice is a viable model system for in vivo studies of prostatic disease

Characterization of monoclonal antibodies that define rat T cell alloantigens.

Abstract A panel of monoclonal antibodies with specificity for rat T cell alloantigens was prepared by somatic cell hybridization with the use of spleen cells from either BH (ART-1b, 2b) or NBR (ART-1b, 2a) rats immunized with LEW (ART-1a, 2a) thymus, spleen, or lymph node cells. Comparison of the antibodies resulted in three distinct patterns of complement-mediated cytotoxicity. Further comparison of four representative hybridoma antibodies with antisera having specificity for ART antigens by indirect immunofluorescence demonstrated that two of the three patterns corresponded to anti-ART-1a and anti-ART-2a specificities. The patterns of binding of the anti-ART hybridomas were shown to be different from those produced by mouse monoclonal antibodies having anti-leukocyte-common (L-C) or anti-Thy-1.1 activities as well as antibodies produced by the monoclonal W3/25, which detect a subpopulation of T lymphocytes. Functional studies performed in vitro with cells fractionated by treatment with the monoclonal anti-ART antibodies and complement showed the ART-1 determinant recognized by the hybridoma products BC 84A or BY 12.3 is expressed by mature cytolytic T lymphocytes (CTL) and by cells involved in the generation of CTL during MLR, but not plaque-forming cells. Together, the data suggest the antibodies BC 84A and BY 12.3 can be used to define rat T cell populations. To date, the functional significance of cell populations recognized by monoclonal antibodies having anti-ART-2a or anti-ART-3-like activities has not been determined.</jats:p