Short Oral Treatment Research Articles

Cladribine Alters Immune Cell Surface Molecules for Adhesion and Costimulation: Further Insights to the Mode of Action in Multiple Sclerosis.

Cladribine (CLAD) is a deoxyadenosine analogue prodrug which is given in multiple sclerosis (MS) as two short oral treatment courses 12 months apart. Reconstitution of adaptive immune function following selective immune cell depletion is the presumed mode of action. In this exploratory study, we investigated the impact of CLAD tablets on immune cell surface molecules for adhesion (CAMs) and costimulation (CoSs) in people with MS (pwMS). We studied 18 pwMS who started treatment with CLAD and 10 healthy controls (HCs). Peripheral blood mononuclear cells were collected at baseline and every 3 months throughout a 24-month period. We analysed ICAM-1, LFA-1, CD28, HLADR, CD154, CD44, VLA-4 (CD49d/CD29), PSGL-1 and PD-1 with regard to their expression on B and T cells (T helper (Th) and cytotoxic T cells (cT)) and surface density (mean fluorescence intensity, MFI) by flow cytometry. The targeted analysis of CAM and CoS on the surface of immune cells in pwMS revealed a higher percentage of ICAM-1 (B cells, Th, cT), LFA-1 (B cells, cT), HLADR (B cells, cT), CD28 (cT) and CD154 (Th). In pwMS, we found lower frequencies of Th and cT cells expressing PSGL-1 and B cells for the inhibitory signal PD-1, whereas the surface expression of LFA-1 on cT and of HLADR on B cells was denser. Twenty-four months after the first CLAD cycle, the frequencies of B cells expressing CD44, CD29 and CD49d were lower compared with the baseline, together with decreased densities of ICAM-1, CD44 and HLADR. The rate of CD154 expressing Th cells dropped at 12 months. For cT, no changes were seen for frequency or density. Immune reconstitution by oral CLAD was associated with modification of the pro-migratory and -inflammatory surface patterns of CAMs and CoSs in immune cell subsets. This observation pertains primarily to B cells, which are key cells underlying MS pathogenesis.

Comparative activity of azithromycin and doxycycline against Brucella spp. infection in mice

The activities of a short therapeutic regimen with azithromycin and the classic treatment doxycycline with streptomycin were compared and evaluated in mice infected with Bruce/la melitensis. In a chronic model, starting therapy 31 days after challenger, azithromycin (1 O days, 50 significantly reduced the infection (2.9 logs, day 48 post-infection). The effectiveness of doxycycline (21 days, 50 mg/kg/12 hourly) was greater than azithromycin (4.1 logs of reduction, day 48 post-infection) and when doxycycline was administered for a period of 45 days, all the animals were bacteriologically cured from day 78. The combination with streptomycin (14 days, 1 O mg/kg/day) did not improve the effect of any of the regimens. In an acute model infestion, treatments with doxycycline or doxycycline-streptomycin, for a period of 3 days, starting 1 day after lethal challenge, were able to protect all the mice. In contrast, only 50% of the mice treated with azithromycin survived the challenge. In conclusion, although a short oral treatment with azithromycin was able to reduce the infestion significantly, it was not able to cure the animals as effectively as the classic regimen with doxycycline administered for a longer period of time.

First study on efficacy and tolerability of a new alkylphosphocholine molecule (oleylphosphocholine—OlPC) in the treatment of canine leishmaniosis due to Leishmania infantum

The alkylphosphocholine oleylphosphocholine (OlPC) represents a potential new therapy for the treatment of canine leishmaniosis caused by Leishmania infantum. The aim of the present study was to evaluate the efficacy and safety of OlPC in a small cohort of dogs naturally infected with L. infantum and defined as clinically sick (LeishVet stages II and III). A total of eight dogs were included in the study and were treated orally with 4 mg/kg OlPC for 14 days. Dogs were assessed at the clinical and parasitological level at four time points during a total follow-up period of 90 days (before treatment and at 15, 30, and 90 days post-treatment onset). Ln-PCR, real-time quantitative PCR, antibody testing (IFAT), and culture of bone marrow aspirates were evaluated at the four time points. OlPC treatment induced a rapid and satisfactory clinical recovery in terms of clinical score reduction and weight gain, and treatment efficacy was found to be associated with a decrease in bone marrow parasitic load. Serological titers measured by IFAT were stable in any of the treated dogs at any time point after treatment. OlPC was well tolerated and no severe adverse events were noted in any of the treated dogs; even some dogs showed slight intestinal disorders. This proof-of-principle study is the first to show that short oral treatment with OlPC improves clinical signs of canine L. infantum leishmaniosis, highlighting the need to perform additional studies to optimize the dosing regimen and to assess long-term treatment efficacy of this drug.

Tolerogenic dendritic cells induced by vitamin D receptor ligands enhance regulatory T cells inhibiting allograft rejection and autoimmune diseases

Dendritic cells not only induce but also modulate T-cell activation and function. 1,25-dihydroxyvitamin D3 (1,25(OH)2D3), the prototypic vitamin D receptor (VDR) ligand, is a hormone that induces dendritic cells with a tolerogenic phenotype, characterized by decreased expression of CD40, CD80, and CD86 costimulatory molecules, low interleukin (IL)-12 and enhanced IL-10 secretion [1.Penna G. Adorini L. 1 alpha,25-dihydroxyvitamin D3 inhibits differentiation, maturation, activation, and survival of dendritic cells leading to impaired alloreactive T cell activation.J Immunol. 2000; 164: 2405-2411Crossref PubMed Scopus (1093) Google Scholar]. We have found that a short treatment with 1,25(OH)2D3 induces tolerance to fully mismatched mouse islet allografts that is stable to challenge with donor-type spleen cells and allows acceptance of donor-type vascularized heart grafts. This effect is enhanced by coadministration of mycophenolate mofetil, a selective inhibitor of T- and B-cell proliferation, that has also effects similar to 1,25(OH)2D3 on dendritic cells [2.Gregori S. Casorati M. Amuchastegui S. et al.Regulatory T cells induced by 1 alpha,25-dihydroxyvitamin D(3) and mycophenolate mofetil treatment mediate transplantation tolerance.J Immunol. 2001; 167: 1945-1953Crossref PubMed Scopus (555) Google Scholar]. Graft acceptance is associated with impaired development of type 1 CD4+ and CD8+ cells and an increased percentage of CD4+ CD25+ regulatory cells expressing CD152 in the spleen and in the draining lymph node. Transfer of CD4+ CD25+ cells from tolerant mice protects 100% of the syngeneic recipients from islet allograft rejection. CD4+ CD25+ cells that are able to inhibit the T-cell response to a pancreatic autoantigen and to significantly delay disease transfer by pathogenic CD4+ CD25− cells are also induced by treatment of adult nonobese diabetic mice with 1,25-dihydroxy-16,23Z-diene-26,27-hexafluoro-19-nor vitamin D3 (BXL-922). This treatment arrests progression of insulitis and Th1 cell infiltration, and inhibits diabetes development at non-hypercalcemic doses [3.Gregori S. Giarratana N. Smiroldo S. et al.A 1 alpha,25-dihydroxyvitamin D(3) analog enhances regulatory T-cells and arrests autoimmune diabetes in NOD mice.Diabetes. 2002; 51: 1367-1374Crossref PubMed Scopus (423) Google Scholar]. The enhancement of CD4+ CD25+ regulatory T cells able to mediate transplantation tolerance and to arrest type 1 diabetes development by a short oral treatment with small organic compounds that induce tolerogenic dendritic cells, like VDR ligands, suggests possible clinical applications of this approach. VDR ligands can inhibit not only acute but also chronic allograft rejection, as documented by inhibition of adventitial inflammation and intimal hyperplasia in murine aortic allografts [4.Raisanen-Sokolowski A.K. Pakkala I.S. Samila S.P. et al.A vitamin D analog, MC1288, inhibits adventitial inflammation and suppresses intimal lesions in rat aortic allografts.Transplantation. 1997; 63: 936-941Crossref PubMed Scopus (49) Google Scholar]. While the prevention of leukocyte infiltration into the adventitia is probably due to the immunomodulatory properties of VDR analogues, the inhibition of intimal cell proliferation, both endothelial and smooth muscle cells, is likely induced by their capacity to regulate cell growth. Thus, VDR ligands have pleiotropic immunoregulatory activities that are able to control allograft rejection. Antigen-presenting cells (APCs) and T cells can be direct targets of the hormone, leading to the inhibition of pathogenic effector T cells and enhancing the frequency of T cells with suppressive properties, largely via induction of tolerogenic dendritic cells [5.Mathieu C. Adorini L. The coming of age of 1,25-dihydroxyvitamin D(3) analogs as immunomodulatory agents.Trends Mol Med. 2002; 8: 174-179Abstract Full Text Full Text PDF PubMed Scopus (434) Google Scholar]. These immunoregulatory activities, coupled with the absence of major side effects once calcemia is under control, have been translated into effective immunointervention in a variety of graft rejection models [6.Adorini L. 1,25–dihydroxyvitamin D3 analogs as potential therapies in transplantation.Curr Opin Investig Drugs. 2002; 3: 1458-1463PubMed Google Scholar]. This body of knowledge represents a sound basis to further explore the immunoregulatory properties of VDR ligands in allograft rejection, and in particular in chronic rejection. Induction of tolerance to allografts remains an unfulfilled goal in clinical transplantation, and VDR ligands could be part of a tolerogenic regimen designed to achieve this goal.

Tolerogenic dendritic cells induced by vitamin D receptor ligands enhance regulatory T cells inhibiting autoimmune diabetes.

Dendritic cells (DCs) not only induce but also modulate T cell activation. 1,25-Dihydroxyvitamin D(3) [1,25-(OH)(2)D(3)] induces DCs with a tolerogenic phenotype, characterized by decreased expression of CD40, CD80, and CD86 co-stimulatory molecules, low IL-12, and enhanced IL-10 secretion. We have found that a short treatment with 1,25-(OH)(2)D(3) induces tolerance to fully mismatched mouse islet allografts, and that this tolerance is stable to challenge with donor-type spleen cells and allows acceptance of donor-type vascularized heart grafts. This effect is enhanced by co-administration of mycophenolate mofetil (MMF), a selective inhibitor of T and B cell proliferation, that also has effects similar to 1,25-(OH)(2)D(3) on DCs. Graft acceptance is associated with impaired development of type 1 CD4(+) and CD8(+) cells and an increased percentage of CD4(+)CD25(+) regulatory cells expressing CD152 in the spleen and in the draining lymph node. Transfer of CD4(+)CD25(+) cells from tolerant mice protects 100% of the syngeneic recipients from islet allograft rejection. CD4(+)CD25(+) cells that are able to inhibit the T cell response to a pancreatic autoantigen and to significantly delay disease transfer by pathogenic CD4(+)CD25(-) cells are also induced by treatment of adult nonobese diabetic (NOD) mice with a selected vitamin D receptor (VDR) ligand. This treatment arrests progression of insulitis and Th1 cell infiltration, and inhibits diabetes development at non-hypercalcemic doses. The enhancement of CD4(+)CD25(+) regulatory T cells able to mediate transplantation tolerance and to arrest type 1 diabetes development by a short oral treatment with small organic compounds that induce tolerogenic DCs, like VDR ligands, suggests possible clinical applications of this approach.

Tolerogenic dendritic cells induced by vitamin D receptor ligands enhance regulatory T cells inhibiting allograft rejection and autoimmune diseases.

Dendritic cells (DCs) not only induce but also modulate T cell activation. 1,25-dihydroxyvitamin D(3) [1,25(OH)(2)D(3)] induces DCs with a tolerogenic phenotype, characterized by decreased expression of CD40, CD80, and CD86 costimulatory molecules, low IL-12 and enhanced IL-10 secretion. We have found that a short treatment with 1,25(OH)(2)D(3) induces tolerance to fully mismatched mouse islet allografts that is stable to challenge with donor-type spleen cells and allows acceptance of donor-type vascularized heart grafts. This effect is enhanced by co-administration of mycophenolate mofetil (MMF), a selective inhibitor of T and B cell proliferation that has also effects similar to 1,25(OH)(2)D(3) on DCs. Graft acceptance is associated with an increased percentage of CD4(+)CD25(+) regulatory cells in the spleen and in the draining lymph node that can protect 100% of syngeneic recipients from islet allograft rejection. CD4(+)CD25(+) cells, able to inhibit the T cell response to a pancreatic autoantigen and to significantly delay disease transfer by pathogenic CD4(+)CD25(-) cells, are also induced by treatment of adult nonobese diabetic (NOD) mice with 1,25-dihydroxy-16,23Z-diene-26,27-hexafluoro-19-nor vitamin D(3) (BXL-698). This treatment arrests progression of insulitis and Th1 cell infiltration, and inhibits diabetes development at non-hypercalcemic doses. The enhancement of CD4(+)CD25(+) regulatory T cells, able to mediate transplantation tolerance and to arrest type 1 diabetes development by a short oral treatment with VDR ligands, suggests possible clinical applications of this approach.

Day-to-day follow-up after a short oral treatment of acute vaginal candidosis with itraconazole.

Seventeen patients with acute vaginal candidosis were treated for 2 days with itraconazole (200 mg daily). During 5 days after the start of the treatment, patients were daily screened for the presence of Candida (culture and microscopy) and the presence of signs and symptoms. Four days after treatment, no Candida could be detected in smears of vaginal fluid and cultures from these patients. At that time leucorrhoea, pruritus, vulvitis, and erythema were strongly reduced but had not completely disappeared.