Shoshana Reich

Cannabidiol lowers incidence of diabetes in non-obese diabetic mice

Cannabidinoids are components of the Cannabis sativa (marijuana) plant that have been shown capable of suppressing inflammation and various aspects of cell-mediated immunity. Cannabidiol (CBD), a non-psychoactive cannabidinoid has been previously shown by us to suppress cell-mediated autoimmune joint destruction in an animal model of rheumatoid arthritis. We now report that CBD treatment significantly reduces the incidence of diabetes in NOD mice from an incidence of 86% in non-treated control mice to an incidence of 30% in CBD-treated mice. CBD treatment also resulted in the significant reduction of plasma levels of the pro-inflammatory cytokines, IFN-γ and TNF-α. Th1-associated cytokine production of in vitro activated T-cells and peritoneal macrophages was also significantly reduced in CBD-treated mice, whereas production of the Th2-associated cytokines, IL-4 and IL-10, was increased when compared to untreated control mice. Histological examination of the pancreatic islets of CBD-treated mice revealed significantly reduced insulitis. Our results indicate that CBD can inhibit and delay destructive insulitis and inflammatory Th1-associated cytokine production in NOD mice resulting in a decreased incidence of diabetes possibly through an immunomodulatory mechanism shifting the immune response from Th1 to Th2 dominance.

Use of Recombinant Human Interleukin-2 in Conjunction with Bone Marrow Transplantation as a Model for Control of Minimal Residual Disease in Malignant Hematological Disorders: I. Treatment of Murine Leukemia in Conjunction with Allogeneic Bone Marrow Transplantation and IL-2-Activated Cell-Mediated Immunotherapy

Immunotherapy with recombinant human interleukin-2 (IL-2) and allogeneic spleen cells has led to significant antitumor effects in B-cell leukemia- (BCL1) bearing mice following transplantation with T-lymphocyte-depleted allogeneic bone marrow cells. Graft versus leukemia (GVL) effects were studied in a model mimicking minimal residual disease following bone marrow transplantation (BMT). Lethally irradiated (BALB/c x C57BL/6)F1 recipients were reconstituted with 20 x 10(6) T-lymphocyte-depleted C57BL/6 bone marrow cells mixed with 10(4) to 10(6) BCL1 cells followed by administration of sequential increments of allogeneic C57BL/6 spleen cells; 10(6) cells on Day +1, 10(7) cells on Day +5, and 5 x 10(7) cells on Day +9, with or without concomitant IL-2 treatment (intraperitoneal injections of 20,000 U twice daily for 3 days) together with each spleen cell administration. All mice receiving 10(4)-10(6) BCL1 cells developed marked splenomegaly by Day +21 and all adoptive recipients of 10(5) spleen cells obtained from these mice developed leukemia within 21-36 days. Treatment of mice which received 10(4) BCL1 cells by either three courses of low dose IL-2 or three increments of allogeneic spleen cells alone and certainly by a combination of both resulted in normalization of splenomegaly on Day +21, but only adoptive recipients of 10(5) spleen cells obtained from mice treated by both allogeneic spleen cells and IL-2 (10/10) or allogeneic spleen cells alone (8/10) were disease free (greater than 100 days). Mice inoculated with 10(5) BCL1 cells developed mild splenomegaly on Day +21 after IL2 treatment alone, but showed no clinical evidence of disease following administration of allogeneic spleen cells or both allogeneic spleen cells and IL-2. Following adoptive transfer of 10(5) spleen cells obtained from each treated group no leukemia (greater than 100 days) was evident in recipients of spleen cells obtained from mice treated with both allogeneic spleen cells and IL-2 (10/10) whereas a partial effect was observed in mice treated by allogeneic spleen cells only (4/10). Mice inoculated with a high dose of BCL1 cells (10(6] showed some delay in onset of splenomegaly, but no curative antileukemic effects could be observed even following a synergistic combination of IL-2 and allogeneic spleen cells. Our data suggest that immunocompetent allogeneic lymphocytes may play an important role against leukemic relapse and thus cell therapy may be used therapeutically to treat minimal residual disease after BMT even following initial reconstitution with T-cell-depleted bone marrow cells.(ABSTRACT TRUNCATED AT 400 WORDS)

Cannabidiol arrests onset of autoimmune diabetes in NOD mice

We have previously reported that cannabidiol (CBD) lowers the incidence of diabetes in young non-obese diabetes-prone (NOD) female mice. In the present study we show that administration of CBD to 11-14 week old female NOD mice, which are either in a latent diabetes stage or with initial symptoms of diabetes, ameliorates the manifestations of the disease. Diabetes was diagnosed in only 32% of the mice in the CBD-treated group, compared to 86% and 100% in the emulsifier-treated and untreated groups, respectively. In addition, the level of the proinflammatory cytokine IL-12 produced by splenocytes was significantly reduced, whereas the level of the anti-inflammatory IL-10 was significantly elevated following CBD-treatment. Histological examination of the pancreata of CBD-treated mice revealed more intact islets than in the controls. Our data strengthen our previous assumption that CBD, known to be safe in man, can possibly be used as a therapeutic agent for treatment of type 1 diabetes.

Heparanase prevents the development of type 1 diabetes in non-obese diabetic mice by regulating T-cell activation and cytokines production

Heparanase is an endo‐β‐D‐glucuronidase that cleaves heparan sulfate saccharide chains. The enzyme promotes cell adhesion, migration and invasion, and was shown to play a significant role in cancer metastasis and angiogenesis.

Induction of graft versus leukemia effects by cell-mediated lymphokine-activated immunotherapy after syngeneic bone marrow transplantation in murine B cell leukemia

Abstract The feasibility of inducing graft versus leukemia (GVL) effects with allogeneic T cells in recipients of autologous bone marrow transplantation (BMT) was studied in a murine model (BCL 1) of human B cell leukemia/lymphoma. Allogeneic cell therapy, induced by infusion with peripheral blood lymphocytes, a mixture of allogeneic spleen and lymph node cells and allogeneic activated cell therapy, induced by in vitro recombinant-interleukin-2(rIL-2)-activated allogeneic bone marrow cells in tumor-bearing mice, prevented disease development in adoptive BALB/c recipients. Concomitant in vivo activation of allogeneic lymphocytes with rIL-2 suppressed even more effectively the development of leukemia in secondary adoptive recipients of spleen cells obtained from treated mice. In contrast, in vivo administration of rIL-2 after syngeneic BMT, with or without equal numbers of syngeneic lymphocytes, led to disease development in secondary recipients. Our data suggest that effective cell therapy can be achieved after SBMT by allogeneic but not syngeneic lymphocytes and that anti-leukemic effects induced by allogeneic lymphocytes can be further enhanced by in vitro or in vivo activation of allogeneic effector cells with rIL-2. Therefore, cell therapy by allogeneic lymphocytes following autologous BMT could become an effective method for inducing GVL-like effects on minimal residual disease provided that graft versus host disease can be prevented or adequately controlled.

Induction of Early Post-Transplant Graft-versus-Leukemia Effects Using Intentionally Mismatched Donor Lymphocytes and Elimination of Alloantigen-Primed Donor Lymphocytes for Prevention of Graft-versus-Host Disease

Graft-versus-leukemia (GVL) effects can be induced in tolerant mixed chimeras prepared with nonmyeloablative conditioning. GVL effects can be amplified by post-grafting donor lymphocyte infusion (DLI). Unfortunately, DLI is frequently associated with graft-versus-host disease (GVHD). We investigated the feasibility of induction of potent GVL effects by DLI using intentionally mismatched lymphocytes followed by elimination of alloreactive donor T cells by cyclophosphamide for prevention of lethal GVHD following induction of very short yet most potent GVL effects. Mice inoculated with B-cell leukemia (BCL1) and mismatched donor lymphocytes were treated 2 weeks later with low-dose or high-dose cyclophosphamide. All mice receiving cyclophosphamide 2 weeks after DLI survived GVHD, and no residual disease was detected by PCR; all control mice receiving DLI alone died of GVHD. Analysis of host (female) and donor (male) DNA showed that cyclophosphamide treatment eradicated most alloreactive donor cells, yet mixed chimerism was converted to full donor chimerism following transient self-limited GVHD. Our working hypothesis suggests that short-term yet effective and safe adoptive immunotherapy of leukemia may be accomplished early post-transplantation using alloreactive donor lymphocytes, with prevention of GVHD by elimination of GVL effector cells.

Immunotherapy of murine leukemia following non-myeloablative conditioning with naïve or G-CSF mobilized blood or bone marrow stem cells

Allogeneic stem cell transplantation (SCT) is the treatment of choice for a large number of hematologic malignancies. Its major advantage over conventional chemotherapy lies in the graft-versus-leukemia (GVL) effects mediated by allo- or tumor-reactive donor lymphocytes given in the course of SCT or post transplantation as donor lymphocyte infusions (DLI). The benefits of cell-mediated immunotherapy over myeloablative radiochemotherapy have also made it possible to reduce the intensity of conditioning regimens. Mobilized peripheral blood has proved preferable to bone marrow (BM) as a source of stem cells for transplantation, since it provides a larger number of stem cells on the one hand and immunologically competent lymphocytes on the other. The use of granulocyte colony stimulating factor (G-CSF), which is necessary to mobilize and increase the number of stem cells, may down-regulate the GVL effect by suppression of donor effector T lymphocytes by inducing Th1→Th2 cytokine switch. It has previously been shown that GVL effects may be amplified by both in vivo and in vitro activation of donor lymphocytes with human recombinant interleukin-2 (rIL-2). Our studies using a leukemic murine model prepared for transplantation with low intensity conditioning prior to infusion of G-CSF-mobilized peripheral blood stem cells (PBSC) have demonstrated that mobilization of blood cells with G-CSF and in vivo treatment with rIL-2 following low-intensity conditioning enhances the GVL effects and prolongs survival of recipients inoculated with BCL1. Activation of donor lymphocytes with rIL-2 may thus be useful for amplifying GVL effects following mobilization with G-CSF.