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Porcine circovirus associated disease (PCVAD) complex is caused by co-infections of PCV2 and other common pathogens and/or environmental stressors. Different vaccines have been developed to reduce PCV2 infections and PCVAD. Such vaccines are poorly standardized in terms of antigen payload and recognized correlates of protection. Therefore, we selected twenty, 40-day old piglets, and allocated them to 4 groups (5 animals each) with uniform levels of maternally-derived antibody to PCV2. Animals were vaccinated with 450/150/50/0 nanograms of an inactivated PCV2b strain, formulated in the same adjuvant of the commercial Circovac vaccine. Twenty-seven days later, all pigs were challenged intranasally with the homologous PCV2 strain. The main findings can be summarized as follows: 1) No clinical signs were observed in the pigs under study. 2) Viremia was observed in all the control pigs, as well as in 2 pigs of the 150 and 50 ng groups, respectively. No pigs of the 450-ng group developed viremia. 3) There was no correlation between protection and ELISA Ab titers in the single animals, even though the 450-ng group developed on average a stronger Ab response. 4) All the pigs with a PCV2-specific IFN-gamma response at 3 weeks after vaccination were fully protected against viremia. The IFN-gamma response at this time point was peculiar to CD4+, single positive T cells, whereas both CD8alpha and CD8 beta+ T cells were also positive after challenge infection. 5) In lymphoid tissues (mainly tonsils and ileum) the presence of sparse reactive hystiocytes and multinucleated giant cells was the only PCV2-associated feature and, by immunohistochemistry, only 2 out of 20 subjects (still viremic at 35 PID) had a mild viral load (grade 1 in 8 samples and grade 2 in only 1 sample). Our data point at the IFN-gamma release assay as a useful tool for monitoring efficacy of PCV2 vaccines.

"\"\\\"\\\\\\\"Background The clinical use of ex vivo-expanded T-regulatory cells for the treatment of T-cell-mediated diseases has gained increasing momentum. However, the recent demonstration that FOXP3(+) T-regulatory cells may contain interleukin-17-producing cells and that they can convert into effector cells once transferred in vivo raises significant doubts about their safety. We previously showed that rapamycin permits the ex vivo expansion of FOXP3(+) T-regulatory cells while impairing the proliferation of non-T-regulatory cells. Here we investigated the Th17-cell content and the in vivo stability of rapamycin-expanded T-regulatory cells as pertinent aspects of cell-based therapy. Design and Methods T-regulatory-enriched cells were isolated from healthy volunteers and were expanded ex vivo with rapamycin with a pre-clinical applicable protocol. T-regulatory cells cultured with and without rapamycin were compared for their regulatory activity, content of pro-inflammatory cells and stability. Results We found that CD4(+)CCR6(+)CD161(+) T cells (i.e., precursor\\\\\\\\\\\\\\\/committed Th17 cells) contaminate the T-regulatory cells cultured ex vivo in the absence of rapamycin. In addition, Th17 cells do not expand when rapamycin-treated T-regulatory cells are exposed to a \\\\\\\"Th17-favorable\\\\\\\" environment. Rapamycin-expanded T-regulatory cells maintain their in vitro regulatory phenotype even after in vivo transfer into immunodeficient NOD-SCID mice despite being exposed to the irradiation-induced pro-inflammatory environment. Importantly, no additional rapamycin treatment, either in vitro or in vivo, is required to keep their phenotype fixed. Conclusions These data demonstrate that rapamycin secures ex vivo-expanded human T-regulatory cells and provide additional justification for their clinical use in future cell therapy-based trials.\\\\\\\"\\\"\""

Porcine Sertoli cells (pSC) have been successfully employed as cell therapy in pre-clinical studies of several immune-based and chronic degenerative diseases. In order to prevent any transmission of infectious adventitious agents to the cells graft recipients, we have set up, according to our previously described method (Luca et al., 2007) pSC monolayers obtained from specific pathogen free (SPF) certified neonatal pigs, born in the unique SPF colony in Italy. pSC were assessed and characterized as far as viability, by ethidium bromide and fluorescein diacetate (EB/FD), Müllerian inhibiting substance (AMH), and insulin-like 3 (INSL3), alpha-smooth muscle actin (ASMI) both by immunofluorescence (IF) and cytofluorimetric analysis (CA) were concerned. pSC were encapsulated in alginate microcapsules (MCpSC), with MCp- SC functional competence and biocompatibility being determined both in vitro, by AMH, inhibin B, TGF-beta, IGF-I secretion and in vivo in experimental animal models, respectively. Results demonstrated the high purity of our pSC monolayers (95% of AMH+cells), with negligible contamination by Leydig (2%) and peritubular cells (3%). Microencapsulation did not alter pSC viability and even after 4 months postimplantation, all the retrieved microcapsules retained morphology and function. In conclusion, we have uniquely obtained, from a SPF herd, highly purified, viable and functional pSC that might poten-tially apply to humans., Italian Journal of Anatomy and Embryology, Vol 119, No 1 (Supplement) 2014

The identification of HIV-1 coreceptors has provided a molecular basis for the tropism of different HIV-1 strains. CXC chemokine receptor-4 (CXCR4) mediates the entry of both primary and T cell line-adapted (TCLA) syncytia-inducing strains. Although macrophages (Mφ) express CXCR4, this coreceptor is assumed to be nonfunctional for HIV-1 infection. We addressed this apparent paradox by infecting human monocyte-derived Mφ with primary and TCLA isolates that were rigorously characterized for coreceptor usage and by adding the natural CXCR4 ligand, stem cell differentiation factor-1, to specifically block CXCR4-mediated entry. Our results show that primary HIV-1 isolates that selectively use CXCR4 productively infected both normal and C-C chemokine receptor-5-null Mφ. By contrast, Mφ supported the entry of CXCR4-dependent TCLA strains with variable efficiency but were not productively infected. Thus, the tropism of HIV isolates results from complex virus/host cell interactions both at the entry and postentry levels.

Canine perivascular wall tumors (PWTs) are a group of subcutaneous soft tissue sarcomas developing from vascular mural cells. Mural cells are involved in angiogenesis through a complex crosstalk with endothelial cells mediated by several growth factors and their receptors. The evaluation of their expression may have relevance since they may represent a therapeutic target in the control of canine PWTs. The expression of vascular endothelial growth factor (VEGF) and receptors VEGFR-I/II, basic fibroblast growth factor (bFGF) and receptor Flg, platelet-derived growth factor B (PDGFB) and receptor PDGFRβ, transforming growth factor β1 (TGFβ1) and receptors TGFβR-I/II, and cyclooxygenase 2 (COX2) was evaluated on frozen sections of 40 PWTs by immunohistochemistry and semiquantitatively scored to identify their potential role in PWT development. Statistical analysis was performed to analyze possible correlations between Ki67 labeling index and the expression of each molecule. Proteins of the VEGF-, PDGFB-, and bFGF-mediated pathways were highly expressed in 27 (67.5%), 30 (75%), and 19 (47.5%) of 40 PWTs, respectively. Proteins of the TGFβ1- and COX2-mediated pathways were highly expressed in 4 (10%) and 14 (35%) of 40 cases. Statistical analysis identified an association between VEGF and VEGFR-I/II ( P = .015 and .003, respectively), bFGF and Flg ( P = .038), bFGF and PDGFRβ ( P = .003), and between TGFβ1 and COX2 ( P = .006). These findings were consistent with the mechanisms that have been reported to play a role in angiogenesis and in tumor development. No association with Ki67 labeling index was found. VEGF-, PDGFB-, and bFGF-mediated pathways seem to have a key role in PWT development and growth. Blockade of tyrosine kinase receptors after surgery could represent a promising therapy with the aim to reduce the PWT relapse rate and prolong the time to relapse.

The effects of a chimeric monoclonal antibody (chA6 mAb) that recognizes both the RO and RB isoforms of the transmembrane protein tyrosine phosphatase CD45 on human T cells were investigated. Chimeric A6 (chA6) mAb potently inhibited antigen-specific and polyclonal T cell responses. ChA6 mAb induced activation-independent apoptosis in CD4(+)CD45RO/RB(high) T cells but not in CD8(+) T cells. In addition, CD4(+) T cell lines specific for tetanus toxoid (TT) generated in the presence of chA6 mAb were anergic and suppressed the proliferation and interferon (IFN)-gamma production by TT-specific effector T cells by an interleukin-10-dependent mechanism, indicating that these cells were equivalent to type 1 regulatory T cells. Similarly, CD8(+) T cell lines specific for the influenza A matrix protein-derived peptide (MP.58-66) generated in the presence of chA6 mAb were anergic and suppressed IFN-gamma production by MP.58-66-specific effector CD8(+) T cells. Furthermore, chA6 mAb significantly prolonged human pancreatic islet allograft survival in nonobese diabetic/severe combined immunodeficiency mice injected with human peripheral blood lymphocytes (hu-PBL-NOD/SCID). Together, these results demonstrate that the chA6 mAb is a new immunomodulatory agent with multiple modes of action, including deletion of preexisting memory and recently activated T cells and induction of anergic CD4(+) and CD8(+) regulatory T cells.

Human immunodeficiency virus-1 (HIV-1) expression in monocyte-derived macrophages (MDM) infected in vitro is known to be inhibited by lipopolysaccharide (LPS). However, the mechanisms are incompletely understood. We show here that HIV-1 suppression is mediated by soluble factors released by MDM stimulated with physiologically significant concentrations of LPS. LPS-conditioned supernatants from MDM inhibited HIV-1 replication in both MDM and T cells. Depletion of C–C chemokines (RANTES, MIP-1α, and MIP-1β) neutralized the ability of LPS-conditioned supernatants to inhibit HIV-1 replication in MDM. A combination of recombinant C–C chemokines blocked HIV-1 infection as effectively as LPS. Here, we report an inhibitory effect of C–C chemokines on HIV replication in primary macrophages. Our results raise the possibility that monocytes may play a dual role in HIV infection: while representing a reservoir for the virus, they may contribute to the containment of the infection by releasing factors that suppress HIV replication not only in monocytes but also in T lymphocytes.

We have read the letter by He and Lv[1][1] and we think the issues raised by the authors are not pertinent to our published work. Specifically, He and Lv raise three issues. 1. They claim that we cannot conclude from our study that rapamycin has an intrinsic role in the stability of Treg cells. We

Objective High dose (HD) Ara-C combined with a single HD idarubicin dose (IDA) is an efficient and safe salvage regimen for patients with refractory or relapsed acute lymphoblastic leukemia as indicated by phase II studies. No data are available on the pharmacokinetics of IDA after a rapid HD intravenous infusion. An open phase II pharmacokinetic and clinical study was performed to evaluate antileukemic efficacy, IDA pharmacokinetics and to investigate the presence of IDA and its reduced metabolite idarubicinol (IDAol) in cerebrospinal fluid (CSF) of patients treated with HD-IDA. Patients and methods Twenty-five patients with refractory or relapsed acute lymphoblastic leukemia received Ara-C 3 g/m2 from days 1–5, idarubicin (HD-IDA) 40 mg/m2 as rapid intravenous (i.v.) infusion on day 3 and subcutaneous G-CSF 5 μg/kg from day 7 until PMN recovery. Pharmacokinetics of IDA was evaluated after HD idarubicin administration in nine of these patients. CSF samples were collected in 15 patients at different times. IDA and IDAol concentrations were quantified by a validated HPLC assay described in detail elsewhere. Results Eleven patients (44%, 95% CI: 23–65%) achieved complete remission with median disease free survival for 6 months. After administration of HD-IDA i.v. bolus of 40 mg/m2, plasma level profiles of unchanged drug and IDAol were similar to those previously described after standard dose and measured with the same analytical method. The mean terminal half-life measured for IDA in this group of patients (14.9 h) was not significantly different from the mean value observed after standard dose (13.9 h, P = 0.72). IDAol t 1/2 was also similar after HD-IDA (46.2 h) and standard dose (39.4 h, P = 0.79). Pharmacokinetic data reveal that in our series of patients IDA and IDAol clearances are significantly higher than those observed in patients treated with 12 mg/m2 of IDA but, although the administered dose (mg/m2) of the drug is 3.3 times higher, IDA exposure (measured in terms of AUC) is only 2.3 times and IDAol exposition 2.1 times greater. Furthermore, HD infusion resulted in a ratio between the AUC of parent drug and idarubicinol not different from the value observed with the standard-dose. IDA and IDAol were measurable only in 3 of the 15 cerebrospinal fluid samples collected. Conclusion Responses observed in our series are comparable to those reported with other salvage regimens. The IDA exposure lower than expected may explain the safety of the single i.v. administration of 40 mg/m2 of IDA, combined with HD Ara-C, with a degree of myelosuppression equivalent to that reported with this agent administered in standard doses. Our data do not allow us to clearly attribute this behavior to a pharmacokinetic non-linearity since the baseline creatinine clearance, even within normal values, and patient age are significantly different in the two groups. Cerebrospinal fluid penetration was poor, reaching levels not considered as cytotoxic.

Aims and backgroundIn order to increase the prognostic significance of polymerase chain reaction (PCR) data it has been suggested that quantitative PCR can be used to measure tumor burden. However, this option has not yet been definitely supported or refuted in patients with follicular lymphoma (FL). We decided to evaluate whether knowledge of the quantitative level of minimal residual disease and its variations can be of use in the management of FL patients.MethodsWe used qualitative and competitive PCR to study 11 patients with refractory or relapsed FL harboring the t(14;18) translocation who underwent autologous (nine patients) or allogeneic (two patients) stem cell transplantation (SCT). Competitive PCR was performed with a multiple competitor carrying specific sequences including Bcl2/lgH MBR and mcr, and the β-globin gene.ResultsAfter a median post-SCT follow-up of 44 months (range, 12-62), overall survival was 91% and disease-free survival 82%. The quantitative PCR data showed that: 1) effective chemotherapy before SCT substantially (1-2 log) reduced the tumor burden in the bone marrow (BM); 2) the increase in rearranged DNA detected in BM was associated with disease progression and relapse; 3) a PCR-negative autograft seemed to lead to lasting molecular remission even when it was performed in patients with a low level of BM infiltration before transplant; and 4) allo-SCT made and maintained the BM PCR negative even in the presence of a greater tumor burden before SCT. Six of the nine patients having CR after SCT (four auto and two allo) are in continuous molecular remission.ConclusionsIn FL patients qualitative and quantitative PCR may provide data that can be helpful for the prognostic evaluation of tumor progression and the early detection of impending relapse by highlighting biological features such as the quality of the infused material, the tumor burden at transplant, and the behavior of tumor cells after transplant.

Molecular remission and reconstitution of a full chimera with arsenic trioxide in a patient with acute promyelocytic leukemia relapsed after allogeneic bone marrow transplantation

The aim of our study was to evaluate the impact of an early intensification programme including chemotherapy (CHT), autologous stem cell transplantation (ASCT) and radiation therapy (RT) in patients with primary mediastinal large B cell lymphoma (MLCL) with sclerosis presenting with adverse prognostic factors. Between 1993 and 1999, 19 patients with MLCL were referred to our institution. Four patients were classified as low risk according to the age-adjusted International Prognostic Index (AA-IPI). Fifteen (79%) were categorised in the high–intermediate or high risk group and were considered eligible for ASCT. Induction therapy consisted of VACOP-B (etoposide, doxorubicin, cyclophosphamide, vincristine, prednisone and bleomycin) for 12 weeks. After induction therapy the four low risk patients achieved a complete remission (CR) and did not undergo ASCT. Of the 15 poor risk patients, five achieved CR, seven partial remission (PR), and three showed refractory disease (RD). All these patients received mobilising therapy consisting of high-dose cyclophosphamide. After peripheral stem cell (PSC) collection, to obtain a greater tumor mass reduction before transplantation, the seven patients in PR underwent further treatment with high-dose etoposide and those with RD received two cycles of DHAP (dexamethasone, cytarabine and cisplatin). At the time of ASCT, seven patients were in CR, six in PR and two had RD. After transplantation using BEAM as preparative regimen, all patients but one achieved a CR. Seven patients with minimal (