14 research outputs found
Mycobacterium tuberculosis multi-drug-resistant strain M induces IL-17+ IFNγ- CD4+ T cell expansion through an IL-23 and TGF-β-dependent mechanism in patients with MDR-TB tuberculosis
We have previously reported that T cells from patients with multidrug-resistant tuberculosis (MDR-TB) express high levels of IL-17 in response to the MDR strain M(Haarlem family) of Mycobacterium tuberculosis (M.tuberculosis). Herein, we explore the pathways involved in the induction of h17 cells in MDR-TB patients and healthy tuberculin reactors (PPD+HD) by the M strain and the laboratory strain H37Rv. Our results show that IL-1β and IL-6 are crucial for the H37Rv and M-induced expansion of IL-17+IFNγ¯ and IL-17+IFNγ+ in CD4+ T cells from MDR-TB and PPD+HD. IL-23 plays an ambiguous role in Th1 and Th17 profiles: alone, IL-23 is responsible for M.tuberculosis induced IL-17 and IFNγ expression in CD4+ T cells from PPD+HD whereas, together with TGF-β, it promotes IL-17+IFNγ¯ expansion in MDR-TB. In fact, spontaneous and M.tuberculosis-induced TGF-β secretion is increased in cells from MDR-TB being theM strain the highest inducer. Interestingly, TLR-2 signaling mediates the expansion of IL-17+IFNγ¯ cells and the enhancement of latency-associated protein (LAP) expression in CD14+ and CD4+ T cells from MDR-TB, which suggests that M strain promotes IL-17+IFNγ¯ T cells through a strong TLR-2-dependent TGF-β production by antigenpresenting cells and CD4+ T cells. Finally, CD4+ T cells from MDR-TB patients infected with MDR Haarlem strains show higher IL-17+IFNγ¯ and lower IL-17+IFNγ+ levels than LAM-infected patients. The present findings deepen our understanding on the role of IL-17 in MDR-TB and highlight the influence of the genetic background of the infecting M.tuberculosis strain on the ex vivo Th17 response.Fil: Basile, Juan Ignacio. Consejo Nacional de Investigaciones Científicas y Técnicas. Instituto de Medicina Experimental. Academia Nacional de Medicina de Buenos Aires. Instituto de Medicina Experimental; ArgentinaFil: Kviatcovsky, Denise. Consejo Nacional de Investigaciones Científicas y Técnicas. Instituto de Medicina Experimental. Academia Nacional de Medicina de Buenos Aires. Instituto de Medicina Experimental; ArgentinaFil: Romero, María Mercedes. Consejo Nacional de Investigaciones Científicas y Técnicas. Instituto de Medicina Experimental. Academia Nacional de Medicina de Buenos Aires. Instituto de Medicina Experimental; ArgentinaFil: Balboa, Luciana. Consejo Nacional de Investigaciones Científicas y Técnicas. Instituto de Medicina Experimental. Academia Nacional de Medicina de Buenos Aires. Instituto de Medicina Experimental; ArgentinaFil: Monteserin, Johana. Dirección Nacional de Instituto de Investigación. Administración Nacional de Laboratorio e Instituto de Salud “Dr. C. G. Malbrán”; ArgentinaFil: Ritacco, Gloria Viviana. Dirección Nacional de Instituto de Investigación. Administración Nacional de Laboratorio e Instituto de Salud “Dr. C. G. Malbrán”; ArgentinaFil: López, Beatriz. Dirección Nacional de Instituto de Investigación. Administración Nacional de Laboratorio e Instituto de Salud “Dr. C. G. Malbrán”; ArgentinaFil: Sabio y García, Carmen Alejandra. Consejo Nacional de Investigaciones Científicas y Técnicas. Instituto de Medicina Experimental. Academia Nacional de Medicina de Buenos Aires. Instituto de Medicina Experimental; ArgentinaFil: García, A.. Gobierno de la Ciudad de Buenos Aires. Hospital de Infecciosas “Dr. Francisco Javier Muñiz”; ArgentinaFil: Vescovo, M.. Gobierno de la Ciudad de Buenos Aires. Hospital de Infecciosas “Dr. Francisco Javier Muñiz”; ArgentinaFil: Gonzalez Montaner, Pablo. Gobierno de la Ciudad de Buenos Aires. Hospital de Infecciosas “Dr. Francisco Javier Muñiz”; ArgentinaFil: Palmero, Domingo. Gobierno de la Ciudad de Buenos Aires. Hospital de Infecciosas “Dr. Francisco Javier Muñiz”; ArgentinaFil: Sasiain, María del Carmen. Consejo Nacional de Investigaciones Científicas y Técnicas. Instituto de Medicina Experimental. Academia Nacional de Medicina de Buenos Aires. Instituto de Medicina Experimental; ArgentinaFil: de la Barrera, Silvia Susana. Consejo Nacional de Investigaciones Científicas y Técnicas. Instituto de Medicina Experimental. Academia Nacional de Medicina de Buenos Aires. Instituto de Medicina Experimental; Argentin
CD32 is expressed on cells with transcriptionally active HIV but does not enrich for HIV DNA in resting T cells
The persistence of HIV reservoirs, including latently infected, resting CD4+ T cells, is the major obstacle to cure HIV infection. CD32a expression was recently reported to mark CD4+ T cells harboring a replication-competent HIV reservoir during antiretroviral therapy (ART) suppression. We aimed to determine whether CD32 expression marks HIV latently or transcriptionally active infected CD4+ T cells. Using peripheral blood and lymphoid tissue of ART-treated HIV+ or SIV+ subjects, we found that most of the circulating memory CD32+ CD4+ T cells expressed markers of activation, including CD69, HLA-DR, CD25, CD38, and Ki67, and bore a TH2 phenotype as defined by CXCR3, CCR4, and CCR6. CD32 expression did not selectively enrich for HIV- or SIV-infected CD4+ T cells in peripheral blood or lymphoid tissue; isolated CD32+ resting CD4+ T cells accounted for less than 3% of the total HIV DNA in CD4+ T cells. Cell-associated HIV DNA and RNA loads in CD4+ T cells positively correlated with the frequency of CD32+ CD69+ CD4+ T cells but not with CD32 expression on resting CD4+ T cells. Using RNA fluorescence in situ hybridization, CD32 coexpression with HIV RNA or p24 was detected after in vitro HIV infection (peripheral blood mononuclear cell and tissue) and in vivo within lymph node tissue from HIV-infected individuals. Together, these results indicate that CD32 is not a marker of resting CD4+ T cells or of enriched HIV DNA–positive cells after ART; rather, CD32 is predominately expressed on a subset of activated CD4+ T cells enriched for transcriptionally active HIV after long-term ART
Patients with Multidrug-Resistant Tuberculosis display impaired Th1 responses and enhanced regulatory T-Cell levels in response to an outbreak of Multidrug-Resistant Mycobacterium tuberculosis M and Ra Strains
Fil: Geffner, Laura. Academia Nacional de Medicina. Instituto de Investigaciones Hematológicas Mariano R. Castex; Argentina.Fil: Yokobori, Noemi. Academia Nacional de Medicina. Instituto de Investigaciones Hematológicas Mariano R. Castex; Argentina.Fil: Basile, Juan. Academia Nacional de Medicina. Instituto de Investigaciones Hematológicas Mariano R. Castex; Argentina.Fil: Schierloh, Pablo. Academia Nacional de Medicina. Instituto de Investigaciones Hematológicas Mariano R. Castex; Argentina.Fil: Balboa, Luciana. Academia Nacional de Medicina. Instituto de Investigaciones Hematológicas Mariano R. Castex; Argentina.Fil: Mercedes Romero, María. Academia Nacional de Medicina. Instituto de Investigaciones Hematológicas Mariano R. Castex; Argentina.Fil: Ritacco, Viviana. ANLIS Dr.C.G.Malbrán. Instituto Nacional de Enfermedades Infecciosas; Argentina.Fil: Vescovo, Marisa. Hospital Muñiz. Instituto de Tisioneumonología; Argentina.Fil: Gonzalez Montaner, Pablo. Hospital Muñiz. Instituto de Tisioneumonología; Argentina.Fil: López, Beatriz. ANLIS Dr.C.G.Malbrán. Instituto Nacional de Enfermedades Infecciosas; Argentina.Fil: Barrera, Lucía. ANLIS Dr.C.G.Malbrán. Instituto Nacional de Enfermedades Infecciosas; Argentina.Fil: Alemán, Mercedes. Academia Nacional de Medicina. Instituto de Investigaciones Hematológicas Mariano R. Castex; Argentina.Fil: Sasiain, María C. Academia Nacional de Medicina. Instituto de Investigaciones Hematológicas Mariano R. Castex; Argentina.Fil: de la Barrera, Silvia. Academia Nacional de Medicina. Instituto de Investigaciones Hematológicas Mariano R. Castex; Argentina.Fil: Abbate, Eduardo. Hospital Muñiz. Instituto de Tisioneumonología; Argentina.In Argentina, multidrug-resistant tuberculosis (MDR-TB) outbreaks emerged among hospitalized patients with AIDS in the early 1990s and thereafter disseminated to the immunocompetent community. Epidemiological, bacteriological, and genotyping data allowed the identification of certain MDR Mycobacterium tuberculosis outbreak strains, such as the so-called strain M of the Haarlem lineage and strain Ra of the Latin America and Mediterranean lineage. In the current study, we evaluated the immune responses induced by strains M and Ra in peripheral blood mononuclear cells from patients with active MDR-TB or fully drug-susceptible tuberculosis (S-TB) and in purified protein derivative-positive healthy controls (group N). Our results demonstrated that strain M was a weaker gamma interferon (IFN-gamma) inducer than H37Rv for group N. Strain M induced the highest interleukin-4 expression in CD4(+) and CD8(+) T cells from MDR-and S-TB patients, along with the lowest cytotoxic T-lymphocyte (CTL) activity in patients and controls. Hence, impairment of CTL activity is a hallmark of strain M and could be an evasion mechanism employed by this strain to avoid the killing of macrophages by M-specific CTL effectors. In addition, MDR-TB patients had an increased proportion of circulating regulatory T cells (Treg cells), and these cells were further expanded upon in vitro M. tuberculosis stimulation. Experimental Treg cell depletion increased IFN-gamma expression and CTL activity in TB patients, with M-and Ra-induced CTL responses remaining low in MDR-TB patients. Altogether, these results suggest that immunity to MDR strains might depend upon a balance between the individual host response and the ability of different M. tuberculosis genotypes to drive Th1 or Th2 profiles
Cover crop species can increase or decrease the fertilizer-nitrogen requirement in maize
Cover crop species and termination date could affect fertilizer-N management and N diagnostic methods traditionally used in bare fallow-maize (Zea mays L.) systems. Our objectives were to (a) assess the impact of cover crop termination date on maize yield and response to fertilizer-N, (b) determine maize yield at varying N rates following different cover crop species and mixtures, and (c) evaluate the chlorophyll meter reading (CMR), grain N concentration (Nc), and grain N nutrition index (NNI) as N diagnostic methods. Experiments were conducted at four sites in the southeastern Argentinean Pampas with maize planted after cover crops. Factors investigated were cover crops with vetch (Vicia villosa Roth), vetch-oat (Avena sativa L.) mixture, or bare fallow; early termination of cover crops or about 3 wk later; and maize fertilizer-N at 0, 50, 100, and 200 kg N ha–1. The minimum N rate that maximized grain yield was higher in vetch-oat mixture (100 kg N ha–1) than in vetch (50 kg N ha–1). Maize yield was not affected by cover crops with 200 kg N ha–1. Late termination dates of vetch-oat mixture reduced maize yield by 15% compared with early termination dates, while there was no effect of vetch termination date. Cover crop termination date did not affect yield response to fertilizer-N. Relative CMR at silking, grain NC, and especially grain NNI at maturity were useful tools to diagnose maize N status and cover crop effect. Cover crop management should be considered to adjust the fertilizer N rate and optimize maize productivity.EEA BalcarceFil: Carciochi, Walter Daniel. Universidad Nacional de Mar del Plata. Facultad de Ciencias Agrarias; Argentina.Fil: Carciochi, Walter Daniel. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentina.Fil: Massigoge Ignacio. Universidad Nacional de Mar del Plata. Facultad de Ciencias Agrarias; Argentina.Fil: Massigoge Ignacio. Kansas State University. Department of Agronomy; Estados Unidos.Fil: Lapaz Olveira, A. Universidad Nacional de Mar del Plata. Facultad de Ciencias Agrarias; Argentina.Fil: Reussi Calvo, Nahuel Ignacio. Universidad Nacional de Mar del Plata. Facultad de Ciencias Agrarias; Argentina.Fil: Reussi Calvo, Nahuel Ignacio. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentina.Fil: Reussi Calvo, Nahuel Ignacio. Kansas State University. Department of Agronomy; Estados Unidos.Fil: Cafaro La Menza, Francisco. Universidad Nacional de Mar del Plata. Facultad de Ciencias Agrarias; Argentina.Fil: Sainz Rozas, Hernán René. Instituto Nacional de Tecnología Agropecuaria (INTA). Estación Experimental Agropecuaria Balcarce; Argentina.Fil: Sainz Rozas, Hernán René. Universidad Nacional de Mar del Plata. Facultad de Ciencias Agrarias; Argentina.Fil: Sainz Rozas, Hernán René. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentina.Fil: Barbieri, Pablo. Instituto Nacional de Tecnología Agropecuaria (INTA). Estación Experimental Agropecuaria Balcarce; Argentina.Fil: Barbieri, Pablo. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentina.Fil: Di Napoli, M. Asociación Argentina de Consorcios Regionales de Experimentación Agrícola; Argentina.Fil: Gonzalez Montaner, J. Asociación Argentina de Consorcios Regionales de Experimentación Agrícola; Argentina.Fil: Ciampitti, Ignacio A. Kansas State University. Department of Agronomy; Estados Unidos
Elevated glycolytic metabolism of monocytes limits the generation of HIF1A-driven migratory dendritic cells in tuberculosis
International audienceDuring tuberculosis (TB), migration of dendritic cells (DCs) from the site of infection to the draining lymph nodes is known to be impaired, hindering the rapid development of protective T-cell-mediated immunity. However, the mechanisms involved in the delayed migration of DCs during TB are still poorly defined. Here, we found that infection of DCs with Mycobacterium tuberculosis (Mtb) triggers HIF1A-mediated aerobic glycolysis in a TLR2-dependent manner, and that this metabolic profile is essential for DC migration. In particular, the lactate dehydrogenase inhibitor oxamate and the HIF1A inhibitor PX-478 abrogated Mtb-induced DC migration in vitro to the lymphoid tissue-specific chemokine CCL21, and in vivo to lymph nodes in mice. Strikingly, we found that although monocytes from TB patients are inherently biased toward glycolysis metabolism, they differentiate into poorly glycolytic and poorly migratory DCs compared with healthy subjects. Taken together, these data suggest that because of their preexisting glycolytic state, circulating monocytes from TB patients are refractory to differentiation into migratory DCs, which may explain the delayed migration of these cells during the disease and opens avenues for host-directed therapies for TB
Cancers of the Kidney and Urinary Tract in Patients on Dialysis for End-Stage Renal Disease: Analysis of Data from the United States, Europe, and Australia and New Zealand
The persistence of HIV reservoirs, including latently infected, resting CD4+ T cells, is the major obstacle to cure HIV infection. CD32a expression was recently reported to mark CD4+ T cells harboring a replication-competent HIV reservoir during antiretroviral therapy (ART) suppression. We aimed to determine whether CD32 expression marks HIV latently or transcriptionally active infected CD4+ T cells. Using peripheral blood and lymphoid tissue of ART-treated HIV+ or SIV+ subjects, we found that most of the circulating memory CD32+ CD4+ T cells expressed markers of activation, including CD69, HLA-DR, CD25, CD38, and Ki67, and bore a TH2 phenotype as defined by CXCR3, CCR4, and CCR6. CD32 expression did not selectively enrich for HIV- or SIV-infected CD4+ T cells in peripheral blood or lymphoid tissue; isolated CD32+ resting CD4+ T cells accounted for less than 3% of the total HIV DNA in CD4+ T cells. Cell-associated HIV DNA and RNA loads in CD4+ T cells positively correlated with the frequency of CD32+ CD69+ CD4+ T cells but not with CD32 expression on resting CD4+ T cells. Using RNA fluorescence in situ hybridization, CD32 coexpression with HIV RNA or p24 was detected after in vitro HIV infection (peripheral blood mononuclear cell and tissue) and in vivo within lymph node tissue from HIV-infected individuals. Together, these results indicate that CD32 is not a marker of resting CD4+ T cells or of enriched HIV DNA–positive cells after ART; rather, CD32 is predominately expressed on a subset of activated CD4+ T cells enriched for transcriptionally active HIV after long-term ART
Maraviroc for previously treated patients with R5 HIV-1 infection
Background CC chemokine receptor 5 antagonists are a new class of antiretroviral agents.Methods We conducted two double- blind, placebo- controlled, phase 3 studies - Maraviroc versus Optimized Therapy in Viremic Antiretroviral Treatment- Experienced Patients ( MOTIVATE) 1 and MOTIVATE 2 - with patients who had R5 human immunodeficiency virus type 1 ( HIV- 1) only. They had been treated with or had resistance to three antiretroviral- drug classes and had HIV- 1 RNA levels of more than 5000 copies per milliliter. The patients were randomly assigned to one of three antiretroviral regimens consisting of maraviroc once daily, maraviroc twice daily, or placebo, each of which included optimized background therapy ( OBT) based on treatment history and drug- resistance testing. Safety and efficacy were assessed after 48 weeks.Results A total of 1049 patients received the randomly assigned study drug; the mean baseline HIV- 1 RNA level was 72,400 copies per milliliter, and the median CD4 cell count was 169 per cubic millimeter. At 48 weeks, in both studies, the mean change in HIV- 1 RNA from baseline was greater with maraviroc than with placebo: - 1.66 and - 1.82 log(10) copies per milliliter with the once- daily and twice- daily regimens, respectively, versus - 0.80 with placebo in MOTIVATE 1, and - 1.72 and - 1.87 log(10) copies per milliliter, respectively, versus - 0.76 with placebo in MOTIVATE 2. More patients receiving maraviroc once or twice daily had HIV- 1 RNA levels of less than 50 copies per milliliter ( 42% and 47%, respectively, vs. 16% in the placebo group in MOTIVATE 1; 45% in both maraviroc groups vs. 18% in MOTIVATE 2; P< 0.001 for both comparisons in each study). The change from baseline in CD4 counts was also greater with maraviroc once or twice daily than with placebo ( increases of 113 and 122 per cubic millimeter, respectively, vs. 54 in MOTIVATE 1; increases of 122 and 128 per cubic millimeter, respectively, vs. 69 in MOTIVATE 2; P< 0.001 for both comparisons in each study). Frequencies of adverse events were similar among the groups.Conclusions Maraviroc, as compared with placebo, resulted in significantly greater suppression of HIV- 1 and greater increases in CD4 cell counts at 48 weeks in previously treated patients with R5 HIV- 1 who were receiving OBT. (ClinicalTrials. gov numbers, NCT00098306 and NCT00098722.)