Supplementary Figures 1-8, Table 1 from Adjuvant Combination and Antigen Targeting as a Strategy to Induce Polyfunctional and High-Avidity T-Cell Responses against Poorly Immunogenic Tumors

Background:Acute myeloid leukemia (AML) is a hematologic neoplasm characterized by the proliferation of bone marrow myeloblasts. Most of patients achieve remission after intensive chemotherapy, although they still relapse. The immune system play an important role in the pathogenesis of AML, where myeloblasts are be able to switch the immunological synapsis disabling the generation of an anti‐tumor response. In this sense, the presence of a greater number of Th17 lymphocytes has been described in AML.Aims:To elucidate whether the myeloblats modulate the Th17 population and more specifically the two Th17 subpopulations: CCR4+ and CCR4‐.Methods:From February 2015 to March 2018, 20 AML diagnosed patients at the CHN and 20 controls were included. Blood samples were collected at diagnosis from AML patients and in controls. We identified by flow cytometry the populations of T helper cells (Th1, Th2, Th17 CCR4‐CCR6+, Th17 CCR4+CCR6+) with the following monoclonal antibodies: CD3 Horizon‐V450, CCR3 FITC, IFNγRβ PE, CCR4 PE‐Cy7, CD4 PerCP, CCR6 APC, CD45 APC‐H7, CCR5 FITC, CXCR3 APC in a FACSCanto II. Serum level of cytokines were also analysed by CBA Human Th1/Th2/Th17 Cytokine Kit (BD) for IL‐2, IL‐4, IL‐6, IL‐10, TNFα, IFNγ, and IL‐17A. We also study the polimorfism of IL‐17A (rs2275913) and IL‐17F (rs763780) by allele discrimination by real‐time PCR. The SPSS software was used to perform Student́s test or Mann‐Whitney test for unpaired samples between patients and controls, and simple linear regression was used to study the association between levels of cytokines and Th subpopulations in AML patients. P < 0,05 was considered to be statistically significant.Results:Patients and controls characteristics were showed in table 1. Th1 and Th2 cells levels did not differ between AML patients and controls. The mean of Th17 CCR4‐CCR6+ cells was significantly higher in AML patients (192 ± 178/μl) than those in controls (67 ± 38/μl), and the difference was statistically significant (p = 0,027). However, Th17 CCR4+CCR6+ cells levels did not differ between groups. We did not find significant differences in the levels of IL‐2, IL‐4, TNFα and IFNγ citokines. Th17 related cytokines were significantly higher in AML patients than in controls and statistically significant. The mean of cytokines (pg/ml) in AML and in controls was 32,79 ± 86,64 vs 0 (p < 0,01), 3,03 ± 2,65 vs 0,24 ± 0,52 (p < 0,001), 14,37 ± 14,12 vs 2,38 ± 4,17 (p = 0,012), for IL‐6, IL‐10 and IL‐17A respectively. No association was find by simple linear regression between the levels of IL‐6, IL‐10 and IL‐17A, and the Th17 subpopulations. There are also no significant differences between the polymorphisms studied of IL‐17 in patients and controls.imageSummary/Conclusion:Th17 subpopulations could play a role in the pathophysiology of AML. The most relevant subpopulation described is the Th17 CCR4+CCR6+. Protumoral and antitumor properties have been described for this subpopulation and associated cytokines (IL‐6, IL‐10 and IL‐17A). However, our results show an increase in the levels of the Th17 CCR4‐CCR6+ subpopulation and in IL‐6, IL‐10 and IL‐17A in untreated AML patients. The lack of association between Th17 subpopulations and cytokines implies that AML generates a protumoral microenvironment, where Th17 subpopulation and associated cytokines are regardless regulated by the tumor. Specifically, the downregulation of CCR4 antigen expression prevents the cells from migrating and having an antitumor effect and the upregulation of IL‐6, IL‐10 and IL‐17A secretion very likely from Th17 CCR4+CCR6+ could contribute to the progression of the disease.

Multiple myeloma (MM) is a very heterogeneous disease, characterized by multiple cytogenetic aberrations on plasma cells (PC) that have been traditionally used to predict the outcome of the disease. A mayor issue on the analysis of PC is the sometimes low infiltration of these cells in the bone marrow that hampers cytogenetic studies. To solve this problem we have optimized a selection strategy based on PC immunomagnetic isolation that has allowed us to lower to 1% the minimal PC infiltration requirement without loss of purity, enabling to perform genetic analysis. In this study, we have analyzed 153 bone marrow samples of patients suspected of MM, collected from February 2015 to May 2017 by the Genetics service of the Complejo Hospitalario de Navarra. Clinical characteristics of the patients and PC immunophenotyping, conventional cytogenetics and interphase fluorescence in situ hybridization (iFISH) analyses have been assessed on these samples. In our cohort 90% of the samples had cytogenetic abnormalities, among them 50% presented immunoglobulin rearrangements, 41.9% showed 1q gains, 29.7% showed 1p deletions and 33% presented TP53 deletion.

Liquid biopsy represents an alternative to conventional biopsies for the evaluation of tumors mainly due to its easy sampling. One of the main applications is the enumeration of Circulating Tumor Cells (CTCs) to evaluate tumor progression or response to treatment. The analysis of the functional characteristics of CTCs could give us much more information about their role in order to establish a more personalized treatment for the patients. The major issue that has to be solved is the isolation of the CTC population. Multiple protocols have been developed, however none of them has demonstrated to be the definitive one. In fact, a combination of these techniques has often been performed in order to obtain a purer and viable population of CTCs. In this review we have summarized for the first time the different combinatorial approaches used in the last years to optimize the isolation of CTCs and their limitations.

The use of preemptive antiviral therapy to prevent cytomegalovirus (CMV) disease in allogeneic hematopoietic stem cell transplantation (allo-HSCT) recipients might result in over-treatment, inducing drug-related toxicity and viral resistance. A search for predictive markers is needed to determine requirement for antiviral therapy. Clinical follow-up, in combination with the use of streptamers (STs) and cytokine-intracellular staining, could help to identify patients at high risk for CMV reactivations. To study the immune response and reactivation control by CMV-specific CD8+ T-cell (CMV-CTL) populations, we monitored 25 patients who have undergone allo-HSCT by using ST multimer and intracellular cytokine staining. Our study has revealed that the presence of functional CMV-specific T cells, determined by early interferon γ production or by significant T-cell expansion after first CMV reactivation, correlated with short CMV viremia duration and low number of CMV reactivations. By contrast, the absence of functional CMV-CTLs does correlate with CMV recurrence. These results support that behavior of CMV-specific subpopulations after reactivation influences reactivations and can guide preemptive therapy.

Peripheral blood progenitor cells (PBPCs) have become the major source of hematopoietic progenitor cells for allogeneic transplantation. In February 2008, Zarzio® was approved by the European Medicine Agency for PBPCs mobilization, but this authorization was not based in trials analyzing safety and efficacy for PBPCs mobilization. Since August 2011, Zarzio® has been used at our institution for PBPCs mobilization. In total 36 healthy family donors underwent PBPCs mobilization, 18 with Neupogen® and 18 with Zarzio®. Donor characteristics were equivalent between groups, and no severe adverse effects were registered in the Zarzio® group. The number of CD34 cells collected/Kg recipient body weight was 6.7 × 10 6 (3.8–11.1) in the Zarzio® group versus 8.4 × 10 6 (5.6–16.6) in the Neupogen® group ( P = 0.04). We collected the minimal target cell dose (2 × 10 6 /kg) in all donors from each group and no significant differences were found in the collection of the optimal cell dose (5 × 10 6 /kg) between groups, although 3/18 (16.6%) donors that received Zarzio® failed to mobilize the optimal cell dose compared with 0% in the Neupogen® group. A total of 35 patients proceeded to transplantation (17 in the Zarzio® and 18 in the Neupogen® groups, respectively). Platelet and neutrophil median time to engraftment was comparable between the two groups. Our retrospective study supports the conclusion that Zarzio® mobilization of PBPCs in healthy donors is safe but perhaps not as effective as the reference Neupogen. However, more prospective trials are required to definitively asses the safety and efficacy of G‐CSF biosimilars for PBPCs mobilization in healthy donors. J. Clin. Apheresis 31:48–52, 2016. © 2015 Wiley Periodicals, Inc.

BackgroundMultimer technology is widely used to screen antigen‐specific immune recovery after allogeneic hematopoietic stem cell transplantation (allo‐HSCT) as it enables identification, enumeration, phenotypic characterization and isolation of virus‐specific T‐cells. Novel approaches of multimerization might improve on classical tetramer staining; however, their use as standard monitoring technique to quantify antigen‐specific cells has not been validated yet. We have compared two of these available multimeric complexes: pentamer and streptamer to select the best strategy for the incorporation into clinical monitoring practice.MethodsCMVpp65495‐503‐specific HLA‐A*02:01 CD8+ T lymphocytes (CTLA*02:01‐CMVpp65495‐503) were examined with pentamer and streptamer in peripheral blood cells of 77 healthy volunteers. Quantitative and qualitative analyses were performed to compare the precision and repeatability, sensitivity and accuracy and specificity of both technologies by flow cytometry.ResultsStandard deviation for both techniques was less than 0.05 showing that they are repetitive and precise. Both techniques significantly correlated at high frequencies (rSpearman = 0.9422; P < 0.0001) but it was lost at lower levels (<1%) of CTLA*02:01‐CMVpp65495‐503 (rSpearman = 0.3351; P = 0.1376). Streptamer is more accurate for the detection of CTLA*02:01‐CMVpp65495‐503 providing significantly closer values to the theoretical ones (P < 0.0001) as pentamer binds unspecifically to a notable proportion of non‐CMV‐specific CD8+ T‐cells.ConclusionOur results suggest that streptamer multimer provides precise, accurate and specific results to detect CTLA*02:01‐CMVpp65495‐503 by flow cytometry. Streptamer multimer can be used not only for the monitoring of early CTLA*02:01‐CMVpp65495‐503 reconstitution in immunosuppressed patients following allo‐HSCT but also, in conjunction with its reversibility role, for the isolation of CTLA*02:01‐CMVpp65495‐503 for its future use in adoptive immunotherapy. © 2016 International Clinical Cytometry Society

BACKGROUND:Adoptive transfer of CMV-specific T cells has shown promising results in preventing pathological effects caused by opportunistic CMV infection in immunocompromised patients following allogeneic hematopoietic stem cell transplantation. The majority of studies have used steady-state leukapheresis for CMV-reactive product manufacture, a collection obtained prior to or months after G-CSF mobilization, but the procurement of this additional sample is often not available in the unrelated donor setting. If the cellular product for adoptive immunotherapy could be generated from the same G-CSF mobilized collection, the problems associated with the additional harvest could be overcome. Despite the tolerogenic effects associated with G-CSF mobilization, recent studies described that CMV-primed T cells generated from mobilized donors remain functional.METHODS:MHC-multimers are potent tools that allow the rapid production of antigen-specific CTLs. Therefore, in the present study we have assessed the feasibility and efficacy of CMV-specific CTL manufacture from G-CSF mobilized apheresis using MHC-multimers.RESULTS:CMV-specific CTLs can be efficiently isolated from G-CSF mobilized samples with Streptamers and are able to express activation markers and produce cytokines in response to antigenic stimulation. However, this anti-viral functionality is moderately reduced when compared to non-mobilized products.CONCLUSIONS:The translation of Streptamer technology for the isolation of anti-viral CTLs from G-CSF mobilized PBMCs into clinical practice would widen the number of patients that could benefit from this therapeutic strategy, although our results need to be taken into consideration before the infusion of antigen-specific T cells obtained from G-CSF mobilized samples.

We performed a prospective phase II study to evaluate clinical safety and outcome in 48 patients with steroid-refractory grade II–IV acute graft-versus-host disease (aGVHD) treated with mesenchymal stromal cells (MSCs). Clinical outcomes were correlated to comprehensive analyses of soluble and cellular biomarkers. Complete resolution (CR) of aGVHD at day 28 (CR-28) occurred in 12 (25%) patients, CR lasting >1 month (CR-B) occurred in 24 (50%) patients. One-year overall survival was significantly improved in CR-28 (75 versus 33%, P=0.020) and CR-B (79 versus 8%, P<0.001) versus non-CR patients. A six soluble biomarker-panel was predictive for mortality (HR 2.924; CI 1.485–5.758) when measured before MSC-administration. Suppression of tumorigenicity 2 (ST2) was only predictive for mortality 2 weeks after but not before MSC-administration (HR 2.389; CI 1.144–4.989). In addition, an increase in immature myeloid dendritic cells associated with decreased mortality (HR 0.554, CI 0.389–0.790). Patients had persisting T-cell responses against defined virus- and leukemia-associated antigens. In conclusion, our data emphasize the need to carefully assess biomarkers in cohorts with homogeneous GVHD treatments. Biomarkers might become an additional valuable component of composite end points for the rapid and efficient testing of novel compounds to decrease lifecycle of clinical testing and improve the success rate of phase II/III trials.

Approximately, up to 70 % of the human population is infected with cytomegalovirus (CMV) that persists for life in a latent state. In healthy people, CMV reactivation induces the expansion of CMV-specific T cells up to 10 % of the entire T cell repertoire. On the contrary, CMV infection is a major opportunistic viral pathogen that remains a leading cause of morbidity and mortality after allogeneic hematopoietic stem cell transplantation. Due to the delayed CMV-specific immune recovery, the incidence of CMV reactivation during post-transplant period is very high. Several methods are currently available for the monitoring of CMV-specific responses that help in clinical monitoring. In this review, essential aspects in the immune recovery against CMV are discussed to improve the better understanding of the immune system relying on CMV infection and, thereby, helping the avoidance of CMV disease or reactivation following hematopoietic stem cell transplantation with severe consequences for the transplanted patients.

Background: Cytomegalovirus (CMV)-specific T cell infusion to immunocompromised patients following allogeneic Hematopoietic Stem Cell Transplantation (allo-HSCT) is able to induce a successful anti-viral response. These cells have classically been manufactured from steady-state apheresis samples collected from the donor in an additional harvest prior to G-CSF mobilization, treatment that induces hematopoietic stem cell (HSC) mobilization to the periphery. However, two closely-timed cellular collections are not usually available in the unrelated donor setting, which limits the accessibility of anti-viral cells for adoptive immunotherapy. CMV-specific cytotoxic T cell (CTL) manufacture from the same G-CSF mobilized donor stem cell harvest offers great regulatory advantages, but the isolation using MHC-multimers is hampered by the high non-specific binding to myeloid progenitors, which reduces the purity of the cellular product.Methods: In the present study we describe an easy and fastmethod based on plastic adherence to remove myeloid cell subsets from 11 G-CSF mobilized donor samples. CMV-specific CTLs were isolated from the non-adherent fraction using pentamers and purity and yield of the process were compared to products obtained from unmanipulated samples.Results: After the elimination of unwanted cell subtypes, non-specific binding of pentamers was notably reduced. Accordingly, following the isolation process the purity of the obtained cellular product was significantly improved.Conclusions: G-CSF mobilized leukapheresis samples can successfully be used to isolate antigen-specific T cells with MHC-multimers to be adoptively transferred following allo-HSCT, widening the accessibility of this therapy in the unrelated donor setting. The combination of the clinically translatable plastic adherence process to the antigen-specific cell isolation using MHC-multimers improves the quality of the therapeutic cellular product, thereby reducing the clinical negative effects associated with undesired alloreactive cell infusion.

Chemotherapy and/or radiotherapy regular regimens used for conditioning of recipients of hematopoietic stem cell transplantation (SCT) induce a period of transient profound immunosuppression. The onset of a competent immunological response, such as the appearance of viral-specific T cells, is associated with a lower incidence of viral infections after haematopoietic transplantation. The rapid development of immunodominant peptide virus screening together with advances in the design of genetic and non-genetic viral- and tumoural-specific cellular selection strategies have opened new strategies for cellular immunotherapy in oncologic recipients who are highly sensitive to viral infections. However, the rapid development of cellular immunotherapy in SCT has disclosed the role of the T cell selection method in the modulation of functional cell activity and of in vivo secondary effects triggered following immunotherapy.

Sir, We have read with particular attention the recent article published in the BJC by Alvarez et al (2013). They, through endoscopic ultrasound elastography system and conventional immuno-histochemical assays, perform an intrinsic characterisation of tumour stroma's stiffness, fibroblast density and architecture focusing in type I collagen fibre arrangement, cancer-associated fibroblasts (CAFs) and activated CAF quantification. The analysis of post-treatment tissues from patients treated with nab-paclitaxel and gemcitabine combination showed a decrease in CAF number and changes in collagen architecture. These results reaffirm the potential ability of nab-paclitaxel to target the stroma and to change its phenotype, altering the ‘hard of the rock', as described by Garber (2010), intensifying its permeability to deliver cytotoxic agents such as gemcitabine by increasing tumour vascularisation or enzymatic inhibition (Frese et al, 2012) that would suppose a better pharmacokinetic profile (Von Hoff et al, 2011). Even though it is known the clinical benefit of nab-paclitaxel plus gemcitabine in metastatic pancreatic cancer, the cellular or molecular mechanisms that are expressly addressing this stromal involution have not been appointed yet (Alvarez et al, 2013). In this sense, authors analysed the role of secreted protein, acidic and rich in cysteine (SPARC) although they could not find the correlation between the degree of SPARC expression and clinical or pathological responses due to its high affinity to albumin protein of nab-paclitaxel. SPARC strengthens the accumulation of nab-paclitaxel mediated by albumin in the ‘tumour's Achilles' heel' (Von Hoff, Annual meeting of the American Society of Clinical Oncology, 2009); however, the mere use of this endogenous transport system would not justify the clinical impact of this combined treatment. From our point of view the key may be in what Omary et al (2007) described as ‘a star on the rise' in pancreatic disease: the pancreatic stellate cells (PaSCs; α-SMA+ Nestin++ Vimentin++) because of their role as the main manufacturers of profibrotic extracellular matrix (ECM) components of the pancreatic tumour stroma, and which should match with the activated CAFs (SMA+ Vimentin+ fibroblasts) in Alvareźs paper. In pancreatic cancer, PaSCs show increased proliferation and migration properties, and so they could be a suitable target for nab-paclitaxel because of their ability to interfere with the mitotic activity (Gradishar, 2006). Alvarez et al (2013) demonstrate that although CAFs number decreases in patients treated with nab-paclitaxel plus gemcitabine in neoadjuvant setting, the average of activated CAFs remains unchanged. We would like to explain our hypothesis related to what is happening in the stroma: it could be a transient blockade of activated CAFs metabolism, a quiescent status forced for a pharmacologically active substance. Bachem et al (2005) show that cancer cells (CCs) induce a desmoplastic reaction in pancreatic adenocarcinoma by stimulating PaSCs in a paracrine way. So it could be an indirect elimination of principal fibrogenic mediators that stimulate proliferation (platelet-derived growth factor) and ECM synthesis (fibroblast growth factor -2 and transforming growth factor -s1) of activated PaSCs through the abrogation of CCs. In this sense, the hypothetical presence of surface cellular receptors for nab-paclitaxel in CCs could be an interesting pathway biomarker for the effectiveness of the drug as authors related. On the other hand, the ablation of physiological PaSCs functioning after nab-paclitaxel inclusion, in turn, would break the two-way communication between PaSCs and CCs (Apte et al, 2013). In this context, under normal conditions CCs recruit new PaSCs to their vicinity (Vonlaufen et al, 2008), whereas nab-paclitaxel would temporarily inhibit the main mechanism that rules the desmoplastic reaction. All these molecular mechanisms would allow to maintain and stabilise the activated CAF's number despite them being dysfunctional, and also would decline its CAF progeny. In this sense, Apte et al (2013) and Bachem et al (2005) propose that activated PaSCs can transform into a myofibroblast-like phenotype sub-population with the ability of secreting excess amounts of ECM. In conclusion, due to the dynamic nature of the stromal compartment, it is critically involved in the development and progresion of pancreatic tumours (Heinemann et al, 2013). Before using neadjuvant treatment it may be important to know the stroma's cellular activation grade with regard to PaSCs plus their number. In this sense, PaSCs or activated CAFs could give us ample information about tumoral potential of the stroma itself and so could have an important contribution for the patient's prognosis. Also, the fact that activated CAFs do not decrease after nab-paclitaxel treatment could not mean that these cells are not one of the main actors of stromal disruption but the primary target of nab-paclitaxel.

Sir, We have read with particular attention the recent article published in the BJC by Alvarez et al (2013). They, through endoscopic ultrasound elastography system and conventional immuno-histochemical assays, perform an intrinsic characterisation of tumour stroma’s stiffness, fibroblast density and architecture focusing in type I collagen fibre arrangement, cancer-associated fibroblasts (CAFs) and activated CAF quantification. The analysis of post-treatment tissues from patients treated with nab-paclitaxel and gemcitabine combination showed a decrease in CAF number and changes in collagen architecture. These results reaffirm the potential ability of nab-paclitaxel to target the stroma and to change its phenotype, altering the ‘hard of the rock’, as described by Garber (2010), intensifying its permeability to deliver cytotoxic agents such as gemcitabine by increasing tumour vascularisation or enzymatic inhibition (Frese et al, 2012) that would suppose a better pharmacokinetic profile (Von Hoff et al, 2011). Even though it is known the clinical benefit of nab-paclitaxel plus gemcitabine in metastatic pancreatic cancer, the cellular or molecular mechanisms that are expressly addressing this stromal involution have not been appointed yet (Alvarez et al, 2013). In this sense, authors analysed the role of secreted protein, acidic and rich in cysteine (SPARC) although they could not find the correlation between the degree of SPARC expression and clinical or pathological responses due to its high affinity to albumin protein of nab-paclitaxel. SPARC strengthens the accumulation of nab-paclitaxel mediated by albumin in the ‘tumour’s Achilles’ heel’ (Von Hoff, Annual meeting of the American Society of Clinical Oncology, 2009); however, the mere use of this endogenous transport system would not justify the clinical impact of this combined treatment. From our point of view the key may be in what Omary et al (2007) described as ‘a star on the rise’ in pancreatic disease: the pancreatic stellate cells (PaSCs; α-SMA+ Nestin++ Vimentin++) because of their role as the main manufacturers of profibrotic extracellular matrix (ECM) components of the pancreatic tumour stroma, and which should match with the activated CAFs (SMA+ Vimentin+ fibroblasts) in Alvareźs paper. In pancreatic cancer, PaSCs show increased proliferation and migration properties, and so they could be a suitable target for nab-paclitaxel because of their ability to interfere with the mitotic activity (Gradishar, 2006). Alvarez et al (2013) demonstrate that although CAFs number decreases in patients treated with nab-paclitaxel plus gemcitabine in neoadjuvant setting, the average of activated CAFs remains unchanged. We would like to explain our hypothesis related to what is happening in the stroma: it could be a transient blockade of activated CAFs metabolism, a quiescent status forced for a pharmacologically active substance. Bachem et al (2005) show that cancer cells (CCs) induce a desmoplastic reaction in pancreatic adenocarcinoma by stimulating PaSCs in a paracrine way. So it could be an indirect elimination of principal fibrogenic mediators that stimulate proliferation (platelet-derived growth factor) and ECM synthesis (fibroblast growth factor -2 and transforming growth factor -ß1) of activated PaSCs through the abrogation of CCs. In this sense, the hypothetical presence of surface cellular receptors for nab-paclitaxel in CCs could be an interesting pathway biomarker for the effectiveness of the drug as authors related. On the other hand, the ablation of physiological PaSCs functioning after nab-paclitaxel inclusion, in turn, would break the two-way communication between PaSCs and CCs (Apte et al, 2013). In this context, under normal conditions CCs recruit new PaSCs to their vicinity (Vonlaufen et al, 2008), whereas nab-paclitaxel would temporarily inhibit the main mechanism that rules the desmoplastic reaction. All these molecular mechanisms would allow to maintain and stabilise the activated CAF's number despite them being dysfunctional, and also would decline its CAF progeny. In this sense, Apte et al (2013) and Bachem et al (2005) propose that activated PaSCs can transform into a myofibroblast-like phenotype sub-population with the ability of secreting excess amounts of ECM. In conclusion, due to the dynamic nature of the stromal compartment, it is critically involved in the development and progresion of pancreatic tumours (Heinemann et al, 2013). Before using neadjuvant treatment it may be important to know the stroma’s cellular activation grade with regard to PaSCs plus their number. In this sense, PaSCs or activated CAFs could give us ample information about tumoral potential of the stroma itself and so could have an important contribution for the patient's prognosis. Also, the fact that activated CAFs do not decrease after nab-paclitaxel treatment could not mean that these cells are not one of the main actors of stromal disruption but the primary target of nab-paclitaxel. The authors declare no conflict of interest. LB is a recipient of APPICS predoctoral fellowship from the Departamento de Salud del Gobierno de Navarra. MC is a recipient of PFIS predoctoral fellowship from ISCIII. CM is a recipient of ANABASID from the Departamento de Educación del Gobierno de Navarra.

Event Abstract Back to Event Monitoring early CMV-specific CD8+ T-cell responses after allogeneic stem cell transplantation by HLA-multimers MIRIAM CIAURRIZ1, Lorea Beloki1, Natalia Ramirez1, Cristina Mansilla1, Amaya Zabalza1, Eva Bandres2, Mercedes Rodríguez2 and Eduardo Olavarria2* 1 Fundación Miguel Servet-Navarrabiomed, Spain 2 Hospital de Navarra, Spain We present the results of a pilot study using pentamer (PM) and streptamer (ST) multimer complexes for monitoring CMV-specific CD8+ T-cells (CTLs). We analysed 14 patients that underwent allogeneic Stem Cell Transplantation (allo-SCT). All patients and donors were positive for the HLA-A*02:01 allele. PM and ST were directed against the epitope NLVPMVATV (495-503) of the CMV phosphoprotein 65 (pp65). Samples were obtained at 15-day intervals until day +90 and monthly thereafter. Three patterns were observed. In 2 patients (14%) no CMV-specific-CTLs could be detected despite several CMV reactivations, requiring prolonged cumulative antiviral therapy (67 and 136 days each). In 6 patients (43%) CMV reactivation occurred at a mean of 36 days (10-74) and triggered a rapid increase of CMV-specific-CTLs with a median of 6.9 x 105/L (range 0.02-279.7). The CMV-PCR became immediately negative and antiviral therapy was stopped promptly after a median of 15.3 days (8.7-23). Finally, 6 patients (43%) showed an early immune reconstitution with CMV-specific-CTLs detected with a median of 1.53 x 105/L (range 0.2-54.72) in the absence of CMV-PCR reactivation at a median of 20.5 days (10-34) post-SCT. No CMV-PCR reactivation was observed in this group with a median follow-up of 8 months (3-14). Monitoring CMV-specific-T-cells might be able to distinguish patients at higher risk of recurrent virus reactivation and in need of prolonged antiviral therapy. Patients with increasing CMV-specific-CTLs detectable at the time of CMV-PCR reactivation may only need a short course of antiviral therapy, while those with early CMV-specific-CTLs may be protected from CMV reactivation. Keywords: CMV, Stem Cell Transplantation, pentamer, streptamer, Monitoring, Immunologic Conference: 15th International Congress of Immunology (ICI), Milan, Italy, 22 Aug - 27 Aug, 2013. Presentation Type: Abstract Topic: Translational immunology and immune intervention Citation: CIAURRIZ M, Beloki L, Ramirez N, Mansilla C, Zabalza A, Bandres E, Rodríguez M and Olavarria E (2013). Monitoring early CMV-specific CD8+ T-cell responses after allogeneic stem cell transplantation by HLA-multimers. Front. Immunol. Conference Abstract: 15th International Congress of Immunology (ICI). doi: 10.3389/conf.fimmu.2013.02.00923 Copyright: The abstracts in this collection have not been subject to any Frontiers peer review or checks, and are not endorsed by Frontiers. They are made available through the Frontiers publishing platform as a service to conference organizers and presenters. The copyright in the individual abstracts is owned by the author of each abstract or his/her employer unless otherwise stated. Each abstract, as well as the collection of abstracts, are published under a Creative Commons CC-BY 4.0 (attribution) licence (https://creativecommons.org/licenses/by/4.0/) and may thus be reproduced, translated, adapted and be the subject of derivative works provided the authors and Frontiers are attributed. For Frontiers’ terms and conditions please see https://www.frontiersin.org/legal/terms-and-conditions. Received: 27 Jun 2013; Published Online: 22 Aug 2013. * Correspondence: Mr. Eduardo Olavarria, Hospital de Navarra, Pamplona, Spain, eduardo.olavarria.lopez@cfnavarra.es Login Required This action requires you to be registered with Frontiers and logged in. To register or login click here. Abstract Info Abstract The Authors in Frontiers MIRIAM CIAURRIZ Lorea Beloki Natalia Ramirez Cristina Mansilla Amaya Zabalza Eva Bandres Mercedes Rodríguez Eduardo Olavarria Google MIRIAM CIAURRIZ Lorea Beloki Natalia Ramirez Cristina Mansilla Amaya Zabalza Eva Bandres Mercedes Rodríguez Eduardo Olavarria Google Scholar MIRIAM CIAURRIZ Lorea Beloki Natalia Ramirez Cristina Mansilla Amaya Zabalza Eva Bandres Mercedes Rodríguez Eduardo Olavarria PubMed MIRIAM CIAURRIZ Lorea Beloki Natalia Ramirez Cristina Mansilla Amaya Zabalza Eva Bandres Mercedes Rodríguez Eduardo Olavarria Related Article in Frontiers Google Scholar PubMed Abstract Close Back to top Javascript is disabled. Please enable Javascript in your browser settings in order to see all the content on this page.