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Norata GD, Garlaschelli K, Ongari M, Raselli S, Grigore L, Benvenuto F, Maggi FM, Catapano AL (University of Milan; and Center for the Study of Atherosclerosis, Ospedale Bassini, Cinisello Balsamo; Italy). Effect of the Toll-like receptor 4 (TLR-4) variants on intima-media thickness and monocyte-derived macrophage response to LPS. J Intern Med 2005; 258: 21–27. Toll-like receptor 4 (TLR-4) is believed to contribute to the initiation and progression of atherosclerosis. The association of the D299G polymorphism of the TLR-4 gene with the progression of coronary and carotid atherosclerosis, risk of cardiovascular events and myocardial infarction is controversial. We have investigated whether the presence of the D299G polymorphism and the co-segregated T399I polymorphism affects the intima-media thickness (IMT) in the general population. The PLIC study population ( n = 1256) was genotyped for the D299G and the T399I polymorphisms. The presence of both the D299G and T399I alleles was observed in the 13.0% of the population, carriers of the T399I alone were 1.8% and of the D299G alone were 0.9%. No difference in IMT was detected within the carriers of the D299G and T399I alleles and the wild-type subjects in the PLIC population. Furthermore, we investigated whether monocyte from D299G to T399I subjects present a defective response to CD40, interleukin (IL)-6, monocyte chemotactic protein (MCP)-1, cyclo-oxygenase (COX)-2 and PTX3 expression induced by lipopolysaccharide (LPS). When the monocyte-derived macrophages of these subjects were challenged with LPS (1 μg mL−1), no impact of the polymorphisms on the induction of CD40, MCP-1 and PTX3 was observed. Only IL-6 and COX-2 induction by LPS resulted reduced in the D299G/T399I carriers. The presence of the D299G and T399I polymorphisms of the TLR-4 gene does not play a major role on the progression of carotid atherosclerosis. Macrophages from the subjects carrying the polymorphisms show an impaired response to LPS limited only to a IL-6 and COX-2. [ABSTRACT FROM AUTHOR]

Sporotrichosis is a subacute or chronic fungal infection caused by Sporothrix schenckii, which is commonly acquired by traumatic inoculation of the fungus carried in a contaminated material into the skin. Joint involvement is the most frequent extracutaneous manifestation in immunosuppressed patients. We report the case of an immunocompetent woman who acquired sporotrichosis through the scratch of a sick cat. She presented skin lesions and arthritis possibly because of a hypersensitivity reaction. Treatment resulted in complete cure up to 13 months of clinical and serological follow-up. [ABSTRACT FROM AUTHOR]

Objective: To document the specificity and the mechanism of induction of a novel class II major histocompatibility complex (MHC) antigen by mitogenic growth factors in human mesenchymal stem cells (MSCs) expanded in vitro for translational applications., Methods: Expression of class II MHC molecules was measured in human MSCs and differentiated cells expanded in the presence of fibroblast growth factor 2 (FGF-2), platelet-derived growth factor BB (PDGF-BB), human platelet lysate, or interferon-γ (IFNγ). The roles of cell proliferation and growth factor-induced signaling pathways were investigated as well as the class II MHC assembly machinery and functional capacity., Results: FGF-2 and, to a lesser extent, PDGF-BB induced in adult human MSCs the expression of HLA-DR (normally induced by inflammatory cytokines), which was able to stimulate CD4+ T cells via superantigen binding. In contrast to IFNγ, FGF induced HLA-DR expression only in human MSCs proliferating under its mitogenic effect and not in mouse MSCs or in differentiated human cells. Although it induced cell proliferation, human platelet lysate did not cause HLA-DR expression in human MSCs. HLA-DR expression occurred following FGF-specific binding to its receptor(s), mainly FGF receptor 1, without inducing IFNγ or tumor necrosis factor α expression. Both MAPK/ERK-1/2 and phosphatidylinositol 3-kinase/Akt controlled cell proliferation and HLA-DR expression, but only MAPK/ERK-1/2 controlled the induction of the class II MHC transcription activator protein CIITA, the major determinant of HLA-DR transcription., Conclusion: The induction of functional HLA-DR in proliferating progenitor MSCs is a property of human MSCs that have been expanded with mitogenic growth factors. This has potential biologic significance in the regulation and/or protection of progenitor cell subpopulations under sustained mitogenic proliferation and needs to be taken into account when expanding MSCs for use in in vivo applications., (Copyright © 2010 by the American College of Rheumatology.)

Cytogenetic abnormalities and paroxysmal nocturnal haemoglobinuria (PNH) phenotype are frequent findings in aplastic anaemia patients treated with immunosuppressive therapy (IST). In this study we investigated whether the appearance of clonal haemopoiesis influences patient outcome and survival. 97 patients entered this study and were followed from the onset of the disease for a median follow-up (FU) of 53 months. 93% are alive, 56% achieved complete remission, 30% partial remission, both transfusion independent, and 14% did not respond. Three groups were identified: (A) patients without evidence of emerging clones (71/97); (B) patients who acquired chromosomal abnormalities (13/97); (C) patients who showed low expression of glycosyl phosphatidylinositol anchored proteins (GPI-AP) (PNH phenotype) at presentation or later (16/97). Three patients showed both PIG-AP deficiency and chromosomal abnormalities. The actuarial survival of patients without clonal haemopoiesis (n = 71) at 6 years was 95%, for patients with chromosomal abnormalities (n = 13), 88%, and for patients with PIG-AP deficiency (n = 16), 89%. There was no difference in the probability of becoming transfusion independent in the three groups (93%, 92% and 88% respectively). This study confirmed that a proportion of severe aplastic anaemia (SAA) patients exhibit clonal markers during the time after IST, often coexisting with cytogenetically or phenotypically normal haemopoiesis. There was no significant clinical impact of these abnormalities on transfusion independence and survival at the median follow-up of 4 years.

We carried out studies to quantify Ph-negative progenitors both in steady state and during regeneration after chemotherapy and G-CSF in 23 newly diagnosed chronic myeloid leukaemia (CML) patients (group A) and in 14 individuals more than a year from diagnosis (nine in chronic and five in accelerated phase, group B). In steady-state bone marrow, Ph-negative long-term culture initiating cells (LTC-IC) and Ph-negative colony-forming-cells (CFC) were detected in 18/23 and 14/23 patients of group A versus 3/14 and 3/14 patients of group B (P<0.001 and P<0.02, respectively). The absolute number of mobilized Ph-negative progenitors was markedly higher in group A versus group B (P<0.02 for LTC-IC, P<0.003 for CFC). 12/16 newly diagnosed patients mobilized Ph-negative LTC-IC only and the yield was in the range of normal allogeneic donors. Overall the frequency of Ph-negative LTC-IC in the bone marrow predicted the yield of Ph-negative LTC-IC mobilized into peripheral blood (P<0.001). The bone marrow frequency of Ph-positive LTC-IC was considerably lower than the normal counterpart. Taken together, these findings suggest that normal progenitors are relatively well preserved in newly diagnosed CML patients, but tend to rapidly decline with time. This observation helps in the understanding of the pathogenesis of CML and has potential implications for autografting. The optimal time for a successful collection of Ph-negative circulating progenitors would appear to be soon after diagnosis.

This trial was designed to test the use of CD34+ selected haemopoietic stem cells (HSC) in HLA-mismatched donor-recipient pairs, following intensive conditioning with thiotepa, antilymphocyte globulin (ALG), cyclophosphamide and single-dose total-body irradiation (sTBI). 10 patients aged 16-50 with advanced malignancies and a two- or three-antigen mismatched family donor entered this study. Donor marrow and G-CSF primed peripheral blood cells were processed separately on CD34 columns (Ceprate). The median number of infused CD34+ cells were 5.66 x 10(6)/ kg, with 0.55 x 10(6)/kg CD3+ cells. Nine patients received cyclosporin for graft-versus-host disease (GvHD) prophylaxis. Median neutrophil counts on day 21 were 2 x 10(9)/l with a median platelet count of 60 x 10(9)/l, but CD4 counts remained extremely depressed throughout the study. Acute GvHD was scored as grade 0-I in two patients, as grade II in seven, and grade III in one. Eight patients died at a median interval of 72 d from HSCT (range 20-144) due to cytomegalovirus (CMV) associated interstitial pneumonitis (IP) (n = 5), renal failure (n = 1). GvHD (n = 1) and Aspergillus meningitis (n = 1). Two patients are alive 365-495 d post transplant, one in remission and one in relapse. This study suggests that large numbers of positively selected mismatched HSC can rapidly engraft after intensive conditioning regimen: however, profound post-transplant immunodeficiency leads to a high risk of lethal infectious complications.

Elevated white blood cell counts are frequently found in patients with chronic myeloid leukaemia (CML). Although some studies have disclosed that bone marrow of CML patients may contain some normal Philadelphia-negative early progenitor cells, it has been assumed that the dramatic increase of white blood cells was entirely related to the leukaemic cell expansion. In this study we attempted to quantify the number of normal and leukaemic progenitor cells in the bone marrow and peripheral blood of newly diagnosed CML patients. Bone marrow and peripheral blood cells of eight newly diagnosed CML patients were analysed for clonogenic colony-forming cells (CFC) and very early progenitor cells, i.e. long-term culture initiating cells (LTC-IC). The leukaemic (Ph-positive) or normal (Ph-negative) origin of progenitor cells was revealed by cytogenetic analysis performed on single colonies arising from in-vitro assays. In 6/8 patients the marrow CFC frequency ranged from 400 to 9300/10(6) mononuclear cells (MNC), 0-50% being Philadelphia chromosome negative; the LTC-IC frequency ranged from 0 to 11/10(6) MNC, and were 80-100% Ph-negative. The corresponding absolute values into peripheral blood were: CFC = 1-35.5 x 10(3)/ml, 0-50% Ph-negative, and LTC-IC = 0-2.5 x 10(3)/ml, 0-100% Ph-negative. In one patient, no LTC-IC were detected in either the marrow or the peripheral blood. In conclusion, in the peripheral blood of some CML patients, the number of normal LTC-IC is more than 3 times the number of leukaemic progenitor cells, and is much higher (50 times) than the corresponding value found in normal subjects in steady state (2.5/ml v 124/ml). These data support the concept that leukaemic 'stem cells', with respect to normal ones, may be considerably fewer than previously thought. In addition it is shown that at the beginning of CML high numbers of normal LTC-IC are spontaneously mobilized into the blood. Finally, the presence of Ph-negative early progenitors into the blood may represent a potential source of normal stem cells available for autografting providing they can be separated from leukaemic cells.

We have previously reported that mobilization of Philadelphia (Ph) chromosome-negative progenitors is possible in a significant number of Ph1-positive acute lymphoblastic leukaemia (ALL) and chronic myelogenous leukaemia (CML) patients. In this pilot study we employed the same approach for patients with RAEB-t, secondary AML (sAML) and therapy-related AML (t-AML). All patients except one had double or complex cytogenetic abnormalities in marrow cells before mobilization therapy. All patients received an idarubicin-containing regimen (mini-ICE protocol) followed by rh-G-CSF and the first leukapheresis was performed as they were recovering from aplasia. In six out of nine patients the leukapheresis product was entirely karyotypically normal, combined with a significant number of CFU-GM. CD34+ cells and LTC-IC. Recovery time from mobilization therapy was short and no patient died as a result of the procedure. To date, three patients have undergone autografting using their karyotypically normal collections, of which two (sAML) are alive with karyotypically normal marrow a few months after autografting.

Ten patients in first or second relapse with Philadelphia chromosome acute lymphoblastic leukaemia, ineligible for allogeneic sibling marrow transplantation, were treated with an intensive chemotherapy regimen including idarubicin, intermediate-dose arabinosylcytosine, etoposide and G-CSF. Peripheral blood stem cells were collected by leukapheresis during initial early WBC recovery from chemotherapy-induced aplasia. In 5/10 patients all metaphases in leukapheresis products were found to be Philadelphia-chromosome-negative and they have been used as autotransplants after conditioning with TBI/etoposide/cyclophosphamide (or idarubicin) and G-CSF. All five patients showed sustained engraftment and one of them is alive and well Philadelphia-chromosome-negative 18 months after transplant. These preliminary results suggest that it is possible to recover Philadelphia-chromosome-negative blood stem cells after intensive chemotherapy, even in advanced patients, and to perform autografting with these cells.