The clonal composition of human CD4+CD25+Foxp3+ cells determined by a comprehensive DNA-based multiplex PCR for TCRB gene rearrangements

The characterization of the T-cell receptor (TCR) repertoire of CD4+ regulatory T cells (TR) have been limited due to the RNA degradation that results following permeabilization and fixation as routinely used for intracellular staining of Foxp3. In the present study the clonal composition of human umbilical cord blood (UCB) and adult peripheral blood mononuclear cells (PBMC) CD4+ TR and non-TR was characterized by a DNA-based multiplex PCR which allowed for the consistent clonotypic characterization of cells that have undergone fixation and permeabilization. To validate this method, CD8+ T cells from two HLA A*0201 individuals were sorted and compared clonotypically based upon their ability either to secrete interferon-γ in response to a CMV pp65 epitope or to bind to the corresponding pMHC I tetramer. In the UCB and PBMCs clonotypes shared between the CD4+CD25+Foxp3+ and CD4+CD25+Foxp3− was observed in all 3 UCB and in one adult PBMCs, suggesting that naïve and memory CD4+ TR can share the same clonotypes as CD4+ non-TR in humans

Resectability and Ablatability Criteria for the Treatment of Liver Only Colorectal Metastases:Multidisciplinary Consensus Document from the COLLISION Trial Group

The guidelines for metastatic colorectal cancer crudely state that the best local treatment should be selected from a 'toolbox' of techniques according to patient- and treatment-related factors. We created an interdisciplinary, consensus-based algorithm with specific resectability and ablatability criteria for the treatment of colorectal liver metastases (CRLM). To pursue consensus, members of the multidisciplinary COLLISION and COLDFIRE trial expert panel employed the RAND appropriateness method (RAM). Statements regarding patient, disease, tumor and treatment characteristics were categorized as appropriate, equipoise or inappropriate. Patients with ECOG≤2, ASA≤3 and Charlson comorbidity index ≤8 should be considered fit for curative-intent local therapy. When easily resectable and/or ablatable (stage IVa), (neo)adjuvant systemic therapy is not indicated. When requiring major hepatectomy (stage IVb), neo-adjuvant systemic therapy is appropriate for early metachronous disease and to reduce procedural risk. To downstage patients (stage IVc), downsizing induction systemic therapy and/or future remnant augmentation is advised. Disease can only be deemed permanently unsuitable for local therapy if downstaging failed (stage IVd). Liver resection remains the gold standard. Thermal ablation is reserved for unresectable CRLM, deep-seated resectable CRLM and can be considered when patients are in poor health. Irreversible electroporation and stereotactic body radiotherapy can be considered for unresectable perihilar and perivascular CRLM 0-5cm. This consensus document provides per-patient and per-tumor resectability and ablatability criteria for the treatment of CRLM. These criteria are intended to aid tumor board discussions, improve consistency when designing prospective trials and advance intersociety communications. Areas where consensus is lacking warrant future comparative studies.</p

Graft versus leukemia response without graft versus host disease elicited by adoptively transferred multivirus-specific T-cells

A 12-year-old boy with refractory acute lymphoblastic leukemia received a haploidentical transplant from his mother. As prophylaxis for Epstein-Barr virus (EBV), cytomegalovirus (CMV) and adenovirus, he received ex vivo expanded virus-specific donor T cells 3.5 months after transplant. Four weeks later leukemic blasts bearing the E2A deletion, identified by fluorescent in situ hybridization (FISH), appeared transiently in the blood followed by a FISH-negative hematological remission, which was sustained until a testicular relapse 3.5 months later. Clearance of the circulating leukemic cells coincided with a marked increase in circulating virus-specific T cells. The virus-specific cytotoxic T-cell (CTL) line showed strong polyfunctional reactivity with the patient's leukemic cells but not phytohemagglutinin (PHA) blasts, suggesting that virus-specific CTL lines may have clinically significant antileukemia activity