Effect of Tumor Regression Grade on Survival and Disease-Free Interval in Patients Operated on for Locally Advanced Rectal Cancer.

INTRODUCTION: Colorectal cancer is the fourth leading cause of cancer-related death in both men and women in our population. In this regard, rectal cancer accounts for more than half of colorectal cancer deaths, and its incidence is expected to increase in the coming years. There have been significant changes in neoadjuvant therapy regimens, with promising results, as demonstrated by the recent RAPIDO and PRODIGE23 studies. Around 40% of patients diagnosed with locally advanced rectal cancer show some degree of response to neoadjuvant treatment, with complete tumor regression observed in up to one in five patients. MATERIALS AND METHODS: Retrospective observational study. A total of 181 patients with locally advanced rectal cancer treated with neoadjuvant chemoradiotherapy followed by surgery were analyzed. Clinical and pathological data were collected from the patients, including assessment of tumor regression through histopathological studies after surgery. The Mandard tumor regression grading system was used to categorize tumor response into different grades. RESULTS: The results showed a significant association between the degree of tumor regression and several important clinical outcomes. Specifically, patients with higher tumor regression had significantly better disease-free survival than those with less regression (p = 0.004). In addition, tumor regression was also correlated with the incidence of local recurrence (p = 0.018) and distant metastasis (p = 0.032). These associations suggest that tumor responsiveness to neoadjuvant therapy may influence the long-term progression of the disease. Regarding tumor deposits and the presence of lymphadenopathy, these factors were also found to be significantly associated with clinical outcomes. Patients with tumor deposits had a higher incidence of local recurrence (p = 0.025) and distant metastases (p = 0.041), while the presence of lymphadenopathy increased the risk of local recurrence (p = 0.013). These findings highlight the importance of evaluating not only tumor regression but also other pathological markers to predict prognosis and guide clinical management. CONCLUSIONS: The degree of tumor regression was not an independent predictor of survival compared to other variables such as nodal stage and presence of tumor deposits. This indicates that while tumor regression is an important factor, other elements also play a crucial role in determining the prognosis of patients with locally advanced rectal cancer. This study provides additional evidence for the importance of tumor regression, tumor deposits, and lymphadenopathy as predictors of clinical outcomes in patients with rectal cancer treated with neoadjuvant chemoradiotherapy.

Single metachronous bone metastasis following rectal adenocarcinoma: A case report.

Colorectal cancer (CRC) ranks as the third leading cause of cancer-related mortality in developed countries. While its incidence in early stages has increased due to screening programs, a significant number of patients experience the development of metastases either at the time of diagnosis or during follow-ups. Unlike certain other types of cancer, such as breast, prostate, or lung cancer, where bone tissue is a common site for secondary dissemination, CRC primarily spreads to the lymph nodes, liver and lungs. The occurrence of bone metastases from CRC is rare and usually coincides with tumor involvement in other locations. Risk factors for bone metastases include the location of the primary tumor, the age of the patients, KRAS mutations and the degree of tumor differentiation. Unlike metastases to the liver and lungs, bone metastases tend to be symptomatic, affecting the patient's quality of life and resulting in a poorer prognosis with shorter survival rates. The approach to patient management needs to be personalized. The present study describes the of a patient who underwent surgery for stage IV rectal adenocarcinoma and later developed a metastasis in the costal wall 79 months post-intervention, with no evidence of recurrence at other sites.

Spontaneous cervical hematoma caused by giant parathyroid adenoma in an elderly patient: A case report.

Spontaneous cervical hematoma usually occurs as a consequence of extracapsular bleeding from a parathyroid gland, generally due to the presence of an adenoma (giant adenoma), glandular hyperplasia, cystic component, or, less frequently, due to the existence of a carcinoma. The hematoma can be confined to the cervical compartment or extend to the mediastinum, potentially causing airway compression. Despite this, the recommended management in hemodynamically stable patients consists of surveillance and hospital monitoring with delayed surgery after a few weeks. On the other hand, in those patients with airway compromise and instability, emergency surgery, consisting of cervicotomy and drainage, is mandatory. The present study describes the case of a 78-year-old patient with a medical history of high blood pressure, non-insulin-dependent diabetes mellitus, dyslipidemia, moderate aortic stenosis, chronic kidney disease and sarcoidosis under pharmacological treatment who attended the emergency department due to symptoms of neck pain, an increase in soft tissue, and dyspnea on moderate exertion with an evolution leading to respiratory failure. This was secondary to a diagnosis of spontaneous cervical hematoma that required urgent surgical intervention. The results of histopathological analysis revealed that a giant parathyroid adenoma was responsible for the bleeding. The patient had a complicated post-operative period with a prolonged admission to the intensive care unit.

Malignant adipocytic tumours: A 20­year single­centre retrospective study.

Adipocytic tumours are the most common soft tissue neoplasms. Among them, liposarcoma is the most frequent malignant neoplasm. However, to the best of our knowledge, no previously published study has assessed the evolution and oncological prognosis of the different subtypes of liposarcoma at the retroperitoneal level compared with at other locations. The present study is a retrospective observational study in which all patients were operated on between October 2000 and January 2020 with a histological diagnosis of liposarcoma. Variables, such as age, sex, location, histological type, recurrence, type of treatment and mortality, among others, were analysed. The patients were divided into two groups: Group A (retroperitoneal location) and group B (non-retroperitoneal location). A total of 52 patients with a diagnosis of liposarcoma (17 women and 35 men) and a mean age of 57.2±15.9 years were assessed. A total of 16 patients were classified into group A and 36 into group B. The OR of recurrence was 1.5 (P=0.02) for R1 vs. R0 resection in group A. The OR of recurrence in group B for R1 vs. R0 resection was 1.8 (P=0.77), whereas for R2 vs. R0 resection, the OR was 69 (P=0.011). In conclusion, 52 cases of malignant adipocytic tumours collected during 2000-2020 were analysed with the new World Health Organization classification (updated 2020). Although its recurrence potential and capacity for distant metastasis depended on each histological type, surgical treatment with unaffected margins was the main prognostic factor for survival. The present study identified differences in relation to the survival of each histological subtype and its location, finding greater survival in dedifferentiated liposarcoma, myxoid liposarcoma and pleomorphic liposarcoma located at the extraperitoneal level than in the retroperitoneal location. Resectability was not influenced by liposarcoma location.

Results of the Spanish National Polytrauma Registry. Where are we and where are we heading?

INTRODUCTION: In 2017, the Spanish National Polytrauma Registry (SNPR) was initiated in Spain with the goal to improve the quality of severe trauma management and evaluate the use of resources and treatment strategies. The objective of this study is to present the data obtained with the SNPR since its inception. METHODS: We conducted an observational study with prospective data collection from the SNPR. The trauma patients included were over 14 years of age, with ISS ≥ 15 or penetrating mechanism of injury, from a total of 17 tertiary hospitals in Spain. RESULTS: From 1/1/17 to 1/1/22, 2069 trauma patients were registered. The majority were men (76.4%), with a mean age of 45 years, mean ISS 22.8, and mortality 10.2%. The most common mechanism of injury was blunt trauma (80%), the most frequent being motorcycle accident (23%). Penetrating trauma was presented in 12% of patients, stab wounds being the most common (84%). On hospital arrival, 16% of patients were hemodynamically unstable. The massive transfusion protocol was activated in 14% of patients, and 53% underwent surgery. Median hospital stay was 11 days, while 73.4% of patients required intensive care unit (ICU) admission, with a median ICU stay of 5 days. CONCLUSIONS: Trauma patients registered in the SNPR are predominantly middle-aged males who experience blunt trauma with a high incidence of thoracic injuries. Early addressed detection and treatment of these kind of injuries would probably improve the quality of trauma care in our environment.

Prognostic Factors of Survival in Patients with Peritoneal Metastasis from Colorectal Cancer.

Objectives: The aim of this study was to analyze the prognostic factors of survival in patients with peritoneal metastasis (PM) from colorectal cancer (CRC). The type of relationship between survival and the PM time of detection was used to determine whether it was synchronous with the primary tumor or metachronous. Patients and Methods: Retrospective observational study. It included patients treated for colorectal adenocarcinoma diagnosed between January 2005 and December 2019 who presented PM at the time of diagnosis or during follow-up. Variables, such as sex, age, differentiation grade, positive adenopathy (pN+), tumor size (pT), tumor location, mucinous component, peritoneal carcinomatosis index (PCI), and KRAS mutational status, were analyzed. Results: During the study period, 1882 patients were surgically treated for CRC in our hospital. Of these, 240 patients (12.8%) were included in the study after evidence of PM. The mean age was 67 ± 12 years (range: 32−92 years), and 114 patients were female (47.5%). The mean follow-up was 20 ± 13 months (median 12 months). The Kaplan−Meier survival at 36 months was higher in patients with metachronous PM (24% vs. 8%; p = 0.002), WT-KRAS tumors (31% vs. 15%; p < 0.001), N0 stage (30% vs. 19%; p < 0.001), T3 stage tumors (18% vs. 19% in T4A and 3% in T4B; p > 0.001), and tumors with classic adenocarcinoma histology (18% vs. 8%; p = 0.011). Patients with a PCI of 1−10 showed a likelihood of survival at 36 months of 56%, which was longer than that found in patients with a PCI of 11−20 (8%) or a PCI of >20 (0%) (p < 0.001). In the multiple regression analysis, the factors with an independent prognostic value were: poor grade of differentiation (HR 1.995; 95% CI: 1.294−3.077), KRAS mutation (HR 1.751; 95% CI: 1.188−2.581), PCI 11−20 (HR: 9.935; 95% CI: 5.204−18.966) and PCI > 20 (HR: 4.011; 95% CI: 2.291−7.023). Conclusions: PCI should continue as the as the most useful prognostic indicator in order to assess prognostic estimations as well as therapeutic and surgical decisions, but tumor grade and KRAS mutational status may help in the treatment decision process by providing complementary information. The time of PM detection did not achieve statistical significance in the multiple regression analysis.

Surgical Treatment of Gallstone Ileus: Less Is More.

Introduction: The objective of this study was to evaluate the need for cholecystectomy in patients who underwent surgery for gallstone ileus. Methods: This was a retrospective review of the clinical history of patients who underwent surgery for gallstone ileus between December 1992 and December 2018 and follow-up until October 2020. Data regarding the surgical intervention, location of the obstruction, and surgical procedure performed were collected, as well as complications in relation to biliary pathology in the postoperative period. Results: Twenty-five patients underwent surgery for gallstone ileus. In all patients, except one, the site of the obstruction was identified. The mean age of the patients was 72 (standard deviation [SD] 13.3) years, with a female predominance (18: 7). The patients presented symptoms, on average, 2.9 (1-7) days before going to the emergency room; the primary symptoms were vomiting associated with abdominal pain and constipation (56%). Fifty-six percent of patients were diagnosed preoperatively by imaging tests. In 72% of patients, an enterolithotomy was performed alone without any other intervention on the gallbladder or bile duct. Eighty-three percent of the patients did not present any cholecystobiliary complications during the entire follow-up period, and urgent or delayed cholecystectomy was not performed after the acute episode. Conclusions: Gallstone ileus is a rare entity, and there are no randomized studies that support a preferred treatment. If surgical intervention is required, enterotomy for stone extraction is a safe and effective technique, and in our experience, urgent or delayed cholecystectomy is not necessary.

Clostridium perfringens necrotizing pancreatitis: an unusual pathogen in pancreatic necrosis infection.

Pancreatic necrosis infection (PNI) accounts for about 20-40 % of severe acute pancreatitis. PNI caused by anaerobic bacteria is unusual but when they present, Clostridium perfringens is the microorganism most commonly involved. We present a 60-year-old patient with a previous history of SARS-CoV-2, diagnosed with acute pancreatitis. During the hospitalisation he developed Clostridium perfringens bacteraemia. A CT-scan showed pancreatic gas gangrene and a surgical necrosectomy was performed. Clostridium perfringens was isolated in cultures of the pancreatic tissue and collections. The patient's clinical status improved after surgery and the appropriate medical therapy. He was discharged 76 days after admission. Nowadays, the 'step-up approach' is an accepted therapeutic tool in treatment of pancreatic necrosis and peripancreatic fluid collections. However, most authors suggest that Clostridum perfringens infection requires a more aggressive approach due to the high mortality associated to clostridial infection.

Unusual Case of Gallbladder Adenocarcinoma Metastasis to the Abdominal Wall 11 Years Later: Synchronous Presentation with Two Malignant Colon Tumors, Coincidence or Not?

INTRODUCTION: Abdominal wall masses are a common finding in clinical practice. A high percentage of these masses are malignant. We present the case of a patient operated for a gallbladder adenocarcinoma, who consulted eleven years later for a malignant mass of the abdominal wall in synchrony with two adenocarcinomas of the left colon and sigmoid. Case Report. A 75-year-old male underwent a laparoscopic cholecystectomy with an incidental diagnosis of adenocarcinoma in situ (TisN0M0 according to AJCC 8th edition). The operative report mentioned that the removal of the gallbladder was difficult due to the inflammatory process, and the gallbladder was accidentally opened during the operation. It was not clear from the operative report whether an extraction bag was utilized to remove the specimen, but the histopathological study confirmed an open gallbladder. He presented 11 years later with an asymptomatic heterogeneous complex cystic mass involving the anterior rectus abdominis muscle. Colonoscopy showed synchronous tumors in the descending and sigmoid colon with pathology confirming adenocarcinoma. The patient underwent an elective laparotomy with resection of the anterior abdominal wall mass, left hemicolectomy, and sigmoidectomy. The histopathological results of the abdominal mass (CK7, CK20, EMA, CEA positive) were described as metastasis of adenocarcinoma of biliary origin. Discussion. Port site recurrences are rare complications following laparoscopic surgery when malignancy is unsuspected. Possible factors related to local implantation include direct seeding of spilled bile or tumor cells into the wound or shedding of tumor cells due to pneumoperitoneum-induced loss of the peritoneal barrier at the trocar site. In the absence of distant metastasis, treatment should include wide port site excision with malignancy-free surgical margins. CONCLUSION: Abdominal wall metastasis from gallbladder carcinoma is rare, and its synchronous presentation with a malignant neoplasm of the colon is exceptional. This is the first report of a patient with abdominal wall metastasis from a gallbladder adenocarcinoma operated eleven years ago that debuted synchronously with two adenocarcinomas of the left colon and sigma.

Housing Intervention For Medically Complex Families Associated With Improved Family Health: Pilot Randomized Trial.

The effects of housing instability and homelessness on child and adult health are well documented. However, few studies have explored health and housing interventions for families with children with the objective of health improvement. Housing Prescriptions as Health Care is a randomized controlled trial that is investigating the impact on physical and mental health of integrating priority placement in affordable housing and the provision of services (case management, financial, and legal), compared to the standard of care (providing resource guides and hospital-based social work or care navigation services). In 2016-19 seventy-eight homeless or housing-unstable families defined as "medically complex"-with a child or adult member who used more health services than usual or had a chronic disease or disability-were enrolled in the trial, and sixty-seven completed a six-month follow-up. A difference-in-differences analysis at six months showed decreases in the share of children in fair or poor health and in average anxiety and depression scores among parents in the intervention group, relative to the control group. Findings suggest that a population-specific model that integrates health, housing, legal, and social services can improve health-related outcomes at the household level.

Presentation of a large jejunal artery aneurysm: Management and review of the literature.

INTRODUCTION: Jejunal artery aneurysms (JAAs) constitute less than 1% of all visceral artery aneurysms. They affect mostly men in their fifth decade. In the last years, the widespread of fine cut fine image techniques has increased the number of JAAs diagnosed incidentally. The first case was reported by Levine in 1944. Since then, only a half of hundred cases have been reported. There is a lack of consensus of management of intact JAAs because of the low number of cases published. We present the largest JAA reported in the English literature up to our knowledge. PRESENTATION: We report a 49 year-old woman with a 4 × 5 cm. intact jejunal artery aneurysm found incidentally in a CT. It rose from the first jejunal branch of superior mesenteric artery without signs of rupture. She underwent elective surgery and the aneurysm was completely excised. DISCUSSION: Causes of JAAs include congenital, atherosclerosis or degenerative process. Their rate of rupture depends on location, size and underlying disease and it reaches 10-20% for all visceral artery aneurysms. Risk factors of rupture include pregnancy, hyper-flow situations and connective diseases. Most of cases in the literature presented rupture at the time of diagnosis. JAAs are usually treated following the recommendations for visceral artery aneurysms, so intact JAAs greater than 2 cm. and those causing symptoms should be treated. Treatment includes surgery, embolisation or stent. Surgery is the preferred management for emergency settings. CONCLUSION: JAAs are extremely rare and constitute only 1% of all visceral aneurysms. They are a life-threatening condition.

The identification and isolation of CTCs: A biological Rubik's cube.

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.

Combined Selection System to Lower the Cutoff for Plasma Cell Enrichment Applied to iFISH Analysis in Multiple Myeloma.

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.

Functional specific-T-cell expansion after first cytomegalovirus reactivation predicts viremia control in allogeneic hematopoietic stem cell transplant recipients.

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.

Streptamer technology allows accurate and specific detection of CMV-specific HLA-A*02 CD8+ T cells by flow cytometry.

BACKGROUND: Multimer 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. METHODS: CMVpp65495-503 -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. RESULTS: Standard 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. CONCLUSION: Our 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.

Mobilization of hematopoietic progenitor cells from allogeneic healthy donors using a new biosimilar G-CSF (Zarzio®).

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.

The immune response to cytomegalovirus in allogeneic hematopoietic stem cell transplant recipients.

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.

Assessment of the effector function of CMV-specific CTLs isolated using MHC-multimers from granulocyte-colony stimulating factor mobilized peripheral blood.

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.

CMV-specific T cell isolation from G-CSF mobilized peripheral blood: depletion of myeloid progenitors eliminates non-specific binding of MHC-multimers.

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 fast method 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.

Impact of T cell selection methods in the success of clinical adoptive immunotherapy.

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.