Correction to: Progression of anal intraepithelial neoplasia in HIV-positive individuals: predisposing factors.

Unfortunately, the "Informed consent" statement was incorrectly published in the original version. The complete correct reference should read as follows.

Progression of anal intraepithelial neoplasia in HIV-positive individuals: predisposing factors.

BACKGROUND: The aim of the present study was to evaluate patient factors that affect the progression of anal dysplasia in human immunodeficiency virus (HIV)-positive individuals. METHODS: A retrospective cohort study of HIV-positive adults with human papilloma virus related anal lesions was performed from 2012 to 2017. All patients underwent surgical excision or biopsy and fulguration of lesions in the operating room without using high resolution anoscopy. Patients with initial presentation of squamous cell carcinoma were excluded. The study was designed to investigate progression between the first available histology and either the follow up histology or a negative examination. Patient files were reviewed and data was collected. A bivariate analysis of continuous and categorical variables was performed. RESULTS: One hundred and sixty-one patients met the inclusion criteria. Ninety-seven percent were male. Mean age was 41 years. Thirty-five percent were African American and 47% were Caucasian. After a median follow-up interval of 331 days (IQR 120-615 days) 14 (9%) of patients had progression of disease. Visible lesions on initial presentation, as opposed to lesions found  in patients undergoing examination under anesthesia because of HSIL on anal pap smear, was associated with progression (p = 0.0.2). A lower initial CD4 count (p = 0.01) and initial surgical pathology of anal condylomata (p = 0.01) were also associated with progression. High-risk serotype was associated with no change or regression (p = 0.01). CONCLUSIONS: In our large cohort of HIV-positive patients treated without high resolution anoscopy the rate of progression was low.  Most notably, visible lesions at initial presentation and CD4 count when lower were associated with progression. Initial surgical pathology of anal condylomata was associated with progression, while high-risk serotypes correlated with regression or stability. Identification of risk factors has important implications concerning postoperative surveillance and counseling of HIV-positive patients with anal condylomata/ anal dysplasia.

Prevalence and clinical association of gene mutations through multiplex mutation testing in patients with NSCLC: results from the ETOP Lungscape Project.

Background: Reported prevalence of driver gene mutations in non-small-cell lung cancer (NSCLC) is highly variable and clinical correlations are emerging. Using NSCLC biomaterial and clinical data from the European Thoracic Oncology Platform Lungscape iBiobank, we explore the epidemiology of mutations and association to clinicopathologic features and patient outcome (relapse-free survival, time-to-relapse, overall survival). Methods: Clinically annotated, resected stage I-III NSCLC FFPE tissue was assessed for gene mutation using a microfluidics-based multiplex PCR platform. Mutant-allele detection sensitivity is >1% for most of the ∼150 (13 genes) mutations covered in the multiplex test. Results: Multiplex testing has been carried out in 2063 (76.2%) of the 2709 Lungscape cases (median follow-up 4.8 years). FFPE samples mostly date from 2005 to 2008, yet recently extracted DNA quality and quantity was generally good. Average DNA yield/case was 2.63 µg; 38 cases (1.4%) failed QC and were excluded from study; 95.1% of included cases allowed the complete panel of mutations to be tested. Most common were KRAS, MET, EGFR and PIK3CA mutations with overall prevalence of 23.0%, 6.8%, 5.4% and 4.9%, respectively. KRAS and EGFR mutations were significantly more frequent in adenocarcinomas: PIK3CA in squamous cell carcinomas. MET mutation prevalence did not differ between histology groups. EGFR mutations were found predominantly in never smokers; KRAS in current/former smokers. For all the above mutations, there was no difference in outcome between mutated and non-mutated cases. Conclusion: Archival FFPE NSCLC material is adequate for multiplex mutation analysis. In this large, predominantly European, clinically annotated stage I-III NSCLC cohort, none of the mutations characterized showed prognostic significance.

A novel cysteine cathepsin inhibitor yields macrophage cell death and mammary tumor regression.

Although cysteine cathepsins have been identified as key regulators of cancer growth, their specific role in tumor development remains unclear. Recent studies have shown that high activity levels of tumor cathepsins are primarily a result of increased cathepsin activity in cancer-promoting tumor-associated macrophages (TAMs). To further investigate the role of cysteine cathepsin activity in normal and polarized macrophages, we established in vitro and in vivo models of macrophage differentiation and polarization and used a novel cysteine cathepsin inhibitor, GB111-NH2, to block the activity of cathepsins B, L and S. Here we show that in vitro, cysteine cathepsin inhibition yields both apoptosis and proliferation of macrophages, owing to increased oxidative stress. Proteomic analysis of cathepsin- inhibited macrophages demonstrates inhibition of autophagy, suggesting a likely cause of elevated reactive oxygen species (ROS) levels. In vivo models of mammary cancer further show that cathepsin inhibition yields TAM death owing to increased ROS levels. Strikingly, apoptosis in TAMs yields a seemingly cell non-autonomous death of neighboring cancer cells, and regression of the primary growth. These results show that cysteine cathepsin inhibitors can specifically trigger macrophage cell death and may function as an effective anticancer therapy in tumors with high levels of TAMs.

IL-10 modulates DSS-induced colitis through a macrophage-ROS-NO axis.

Breakdown of the epithelial barrier because of toxins or other insults leads to severe colitis. Interleukin-10 (IL-10) is a critical regulator of this, yet its cellular targets and mechanisms of action are not resolved. We address this here. Mice with a macrophage-selective deletion of IL-10Rα (IL-10Rα(Mdel)) developed markedly enhanced dextran sodium sulfate (DSS)-induced colitis that did not significantly differ from disease in IL-10(-/-) or IL-10Rα(-/-) mice; no impact of IL-10Rα deficiency in other lineages was observed. IL-10Rα(Mdel) colitis was associated with increased mucosal barrier disruption in the setting of intact epithelial regeneration. Lamina propria macrophages (LPMφs) did not show numerical or phenotypic differences from controls, or a competitive advantage over wild-type cells. Proinflammatory cytokine production, and particularly tumor necrosis factor-α (TNF-α), was increased, although TNF-α neutralization failed to reveal a defining role for this cytokine in the aggravated disease. Rather, IL-10Rα(Mdel) LPMφs produced substantially greater levels of nitric oxide (NO) and reactive oxygen species (ROS) than controls. Inhibition of these had modest effects in wild-type mice, although they dramatically reduced colitis severity in IL-10Rα(Mdel) mice, and largely eliminated the differential effect of DSS in them. Therefore, the palliative actions of IL-10 in DSS-induced colitis predominantly results from its macrophage-specific effects. Downregulation of NO and ROS production are central to the protective actions of IL-10.

The HTLV-1 tax protein cooperates with phosphorylated CREB, TORC2 and p300 to activate CRE-dependent cyclin D1 transcription.

Adult T-cell leukemia/lymphoma is a fatal malignancy etiologically linked to infection with the human T-cell leukemia virus (HTLV-1). The virally encoded oncoprotein Tax activates the transcription of HTLV-1 and cellular genes by cooperating with cellular transcription factors. Cyclin D1 is a pivotal regulator of cell cycle progression, and increased expression strongly correlates with malignant transformation. Here, we characterize the mechanism of Tax transactivation of cyclin D1. We find that cyclin D1 transcript levels are elevated in HTLV-1 infected cells and that Tax physically associates with the cyclin D1 gene in vivo. Tax binds the cyclin D1 promoter-proximal cyclic AMP response element (CRE) in the presence of phosphorylated CREB (pCREB) in vitro, and together the Tax-pCREB complex recruits the cellular co-activator p300 to the promoter through this unconventional Tax-responsive element. We further show that the transducer of regulated CREB 2 (TORC2) cooperates with Tax to further enhance p300 recruitment to the cyclin D1 promoter in vitro. Tax and TORC2 in combination stimulate cyclin D1 expression in vivo, demonstrating the functional outcome of the binding interactions. Together, our findings support a model in which Tax-induced accumulation of cyclin D1 shortens the G1 phase of the cell cycle, promotes mitotic replication of the virus, and drives selection and expansion of malignant T-cells.

Induction of tolerance and immunity by redirected B cell-specific cytolytic T lymphocytes.

Chimeric receptors bearing ligand recognition domains linked to signaling regions from the T-cell receptor can redirect T lymphocytes against non-MHC-restricted targets. Cytolytic T lymphocytes (CTL) expressing these chimeric receptors are being tested in preclinical and clinical trials for activity in cancer, infectious diseases and autoimmunity. The chimeric receptors may incorporate antigenic epitopes previously unrecognized by the immune system. Whether a receptor-specific antibody response develops to these neoantigens and whether such a response inhibits therapeutic cell activity is unknown. We hypothesized that upon engagement of a chimeric receptor-specific B cell, receptor-modified CTL will be activated, lysing the B cell and inducing tolerance to the chimeric receptor rather than immunity. We demonstrate that receptor-modified CTL are indeed stimulated by cognate receptor-specific B cells, proliferate and produce cytokines in response and kill the B cells in vitro and in vivo. However, this is insufficient to induce full B-cell tolerance. Modified CTL induce a chimeric receptor-specific antibody response independent of any other source of antigen. Nevertheless, the CTL retain substantial activity even in the presence of saturating doses of receptor-specific antibody. Thus antichimeric receptor antibody responses need to be considered in the clinical use of chimeric receptor-modified T cells. However, the inhibitory activity of these antibodies may in cases be limited.

A large-scale method for the selective depletion of alphabeta T lymphocytes from PBSC for allogeneic transplantation.

BACKGROUND: We sought to develop a method for the clinical large-scale depletion of alphabeta T lymphocytes from mobilized peripheral stem cells, which would allow the allogeneic transplantation of a graft enriched for stem cells, natural killer (NK) cells and gammadelta T lymphocytes. METHODS: Therefore, we obtained mononuclear cells from either mobilized or non-mobilized healthy adult volunteer donors and incubated the cells with a biotinylated anti-alphabeta T-cell Ab and subsequently with an anti-biotin Ab conjugated with magnetic microbeads. The depletion was then performed using a CliniMACS device. RESULTS: The median T-cell depletion was 3.9 log (range 3.5-4.1 log). The recovery of the gammadelta and NK cells was 92% and 80%, respectively. The recovery of CD34+ stem cells from the mobilized donors was 66%. DISCUSSION: This method had no negative influence on the in vitro colony formation of stem cells, and transplantation of alphabeta-depleted cells into NOD-SCID IL-2 common gamma chain knockout (NOD-scid IL2r (null)) mice resulted in a rapid engraftment of human myeloid and lymphoid cells. This method will allow large-scale depletion of alphabeta T cells from mobilized peripheral blood in clinical trials.

Laparoscopic diaphragmatic plication: long-term results of a novel surgical technique for postoperative phrenic nerve palsy.

BACKGROUND: Paralysis of the diaphragm is a severe complication of cardiothoracic surgery carrying significant morbidity and mortality. This study demonstrates a novel minimally invasive technique for treatment of phrenic nerve injuries presenting with symptomatic eventration of the diaphragm. It also presents long-term results of three patients treated with this operation. METHODS: Chest x-ray proved eventration of the left diaphragm in all patients. Two patients required treatment due to prolonged respirator therapy/assisted ventilation for 4 weeks after cardiac surgery. One patient suffered from progressive dyspnea caused by increasing left-sided diaphragmatic elevation and underwent surgery 2 years after cardiac surgery. In all cases, a minimally invasive abdominal approach was chosen. During surgery the dome of the diaphragm was pulled down via three percutaneously inserted retention stitches. This resulted in two or three folds of the diaphragm located within the abdomen. These diaphragmatic folds were subsequently tightened using 12 to 15 unresorbable sutures with extracorporally prepared knots. Surgical as well as long-term follow-up results are presented of all patients and a review of the current literature is provided. RESULTS: Mean operating time was 203 min; mean intraoperative blood loss was 130 ml. No major complications occurred during surgery or the postoperative period. At a median follow-up of 72 months no recurrence was observed. CONCLUSIONS: Laparoscopic diaphragmatic plication provides excellent relief of symptoms caused by diaphragmatic paralysis. There is no perioperative morbidity, and hospital stay is short. The laparoscopic approach, therefore, is an attractive surgical alternative for the treatment of phrenic nerve palsy and should be considered in all suitable patients.

A one-step large-scale method for T- and B-cell depletion of mobilized PBSC for allogeneic transplantation.

BACKGROUND: The presence of T and B cells in allogeneic grafts contributes to GvHD and to EBV-associated lymphoproliferative disease (LPD). Depletion of T and B cells from the graft decreases the risk of these complications. METHODS: T and B cells were depleted from mobilized peripheral stem cells from volunteer donors (n=5) using anti-CD3 and anti-CD19 Abs conjugated to magnetic microbeads, and the CliniMACS device. The function of the stem cells after depletion was evaluated using colony assays and non-obese diabetic (NOD)/SCID repopulating experiments. RESULTS: The mean mononuclear cell (MNC) count prior to T- and B-cell depletion was 2.19x10(10) (range 1.48-3.53). After depletion, the mean percentage of contaminating T cells was 0.02% (range 0.01-0.04%) with a mean log(10) depletion of 3.4 (range 3-3.8). The mean percentage of contaminating B cells was 0.1% (range 0.01-0.4%) with a mean log(10) depletion of 2.2 (range 1.4-3). The mean recovery of CD3- and CD19-negative MNCs after depletion was 70% (range 54-88%) and the mean recovery of CD34(+) stem cells was 69% (range 52-98%). The mean number of natural killer (NK) cells after T- and B-cell depletion was 5.2x10(8) (range 2-10x10(8)). In vitro colony assays and in vivo NOD/SCID repopulation assays showed no negative impact of this method on the function of the hematopoietic stem cells. DISCUSSION: Our results show that the CliniMACS system can be used to efficiently deplete PBSC of T and B cells simultaneously, without adverse effect on the graft.

Chimeric receptors with 4-1BB signaling capacity provoke potent cytotoxicity against acute lymphoblastic leukemia.

To develop a therapy for drug-resistant B-lineage acute lymphoblastic leukemia (ALL), we transduced T lymphocytes with anti-CD19 chimeric receptors, consisting of an anti-CD19 single-chain variable domain (reactive with most ALL cases), the hinge and transmembrane domains of CD8alpha, and the signaling domain of CD3zeta. We compared the antileukemic activity mediated by a novel receptor ('anti-CD19-BB-zeta') containing the signaling domain of 4-1BB (CD137; a crucial molecule for T-cell antitumor activity) to that of a receptor lacking costimulatory molecules. Retroviral transduction produced efficient and durable receptor expression in human T cells. Lymphocytes expressing anti-CD19-BB-zeta receptors exerted powerful and specific cytotoxicity against ALL cells, which was superior to that of lymphocytes with receptors lacking 4-1BB. Anti-CD19-BB-zeta lymphocytes were remarkably effective in cocultures with bone marrow mesenchymal cells, and against leukemic cells from patients with drug-resistant ALL: as few as 1% anti-CD19-BB-zeta-transduced T cells eliminated most ALL cells within 5 days. These cells also expanded and produced interleukin-2 in response to ALL cells at much higher rates than those of lymphocytes expressing equivalent receptors lacking 4-1BB. We conclude that anti-CD19 chimeric receptors containing 4-1BB are a powerful new tool for T-cell therapy of B-lineage ALL and other CD19+ B-lymphoid malignancies.

Antigen-specific targeting of CD8+ T cells with receptor-modified T lymphocytes.

Chimeric receptors that link ligand recognition domains, such as antibody Fv fragments, with TCR signaling domains can redirect T lymphocytes against MHC-unrestricted targets. Such receptor-modified T lymphocytes have shown promise in the treatment of infectious diseases and cancer. We hypothesized that receptor-modified T lymphocytes may also be designed to target antigen-specific T cells. We synthesized chimeric receptors consisting of the extracellular and transmembrane domains of the class I MHC H-2K(b) molecule linked to the signaling domains of either TCR-zeta, CD28 and zeta, or CD28, zeta, and lck. T lymphocytes modified to express these receptors and pulsed with antigenic peptide specifically killed precursor CTL. Cytolysis was efficient, even at effector:target ratios of less than one, and specific, selectively killing antigen-specific precursor CTL among a mixed population of T cells. Cytolysis required activation of the receptor-modified T cells, and did not occur with a signaling-deficient chimeric receptor. In contrast to precursor CTL, differentiated CTL proved resistant to lysis by the receptor-modified T cells. These data demonstrate the feasibility of redirecting T lymphocytes against antigen-specific T cells. Receptor-modified T cells expressing chimeric MHC receptors have potential application in autoimmune and alloimmune diseases.

Large-scale isolation of CD133+ progenitor cells from G-CSF mobilized peripheral blood stem cells.

We have evaluated the feasibility of large-scale isolation of CD133+ progenitors from healthy mobilized adult donors for potential clinical use in autologous and allogeneic transplantation. A total of 11 healthy volunteer adult donors were mobilized with G-CSF. CD133+ stem cells were isolated from a single leukapheresis using the Clinimacs method. The median percentage of CD133 before positive selection was 0.75% (range 0.39-2.03%). After selection, the median purity and recovery was 94% (range 85.2-98.0%) and 69% (range 44-100%), respectively. The median log10 T-cell depletion obtained by CD133+ positive selection was 4.2 (range 3.8-4.7). The CD133+ progenitors were highly enriched in colony-forming units (CFU) and transplantation into NOD/SCID mice resulted in a high engraftment rate. Transplantation of sorted CD133+/CD34+ cells into NOD/SCID mice showed a higher engraftment compared to CD133-/CD34+ cells. Mobilized peripheral CD133+ stem cells can be purified in large scale for potential clinical use. The biological function of the cells is not impaired. The majority of the NOD/SCID repopulating cells are within the CD133+/CD34+ subpopulation. Therefore, clinical studies using purified CD133+ stem cells can be envisoned to further clarify the role of CD133+ stem cells in hematopoietic reconstitution after transplantation.

Techniques and results of esophageal cancer surgery in Germany.

AIMS: This study evaluated the techniques and short-term results of surgical treatment for esophageal cancer in Germany by a nationwide representative survey. METHODS: In 2000 a questionnaire including 63 structured items concerning indication, technique, number of procedures, complications, and hospital mortality was sent to 308 randomly selected general, gastrointestinal, and thoracic surgeons and all university hospitals in Germany (20% of all surgeons). The response rate was 76% ( n=234). RESULTS: In 1999 the 56 participating hospitals performed approximately 370,000 procedures, including 1,677 operations for esophageal diseases, including 891 esophagectomies, 706 for esophageal cancer, 285 for cancer of the cardia. Gastric interposition was the most common technique to restore alimentary tract continuity (86%). Interposition of the colon (ascending colon 64%) is a common procedure only in 22 centers, indicating that experience with this means of esophageal reconstruction is limited. There were no significant differences in complication and mortality rates between gastric transposition and colon interposition. The overall complication rate was 61%, with 36% after gastric interposition and 42% after colon interposition. Anastomotic leakages occurred in 12% and 15%, respectively, and the rate of graft necrosis was 3% in both groups. Hospital mortality was 8% with gastric transposition and 11% with colon interposition. Mean postoperative hospital stay was 24 days. CONCLUSIONS: This study indicates that gastric transposition is frequently used for reconstruction after esophageal resection for malignant disease. It appears that the colon is not as accepted as the stomach for reconstruction, although the reported complication rates compare well with those reported after gastric transposition. This study allows a realistic evaluation of the overall risk of these surgical techniques.

A large-scale method for T cell depletion: towards graft engineering of mobilized peripheral blood stem cells.

We have investigated the feasibility and efficacy of large-scale T cell depletion from granulocyte colony-stimulating factor (G-CSF) mobilized peripheral blood stem cells (PBSC). The method is based on the use of a CD3 antibody conjugated to magnetic microbeads and magnetic activated cell sorting (Clinimacs). A total of eight large-scale experiments were performed. In four experiments, CD3(+) T cells were depleted from PBSC obtained from volunteers mobilized with G-CSF whereas, in four experiments, T cells were depleted from PBSC from stem cell donors, in which the CD34(+) stem cells had been removed for allogeneic transplantation by positive selection prior to T cell depletion. The mean number of processed mononuclear cells (MNCs) was 3.3 x 10(10) (range 1.5 x 10(10)-5.1 x 10(10)) with a mean T cell proportion of 35.8% (range 16.7-64.0%). After T cell depletion, the percentage of contaminating T cells was 0.15% (range 0.01-1.01%) with a mean log(10) depletion of 3.4 (range 2.8-4.1). The mean recovery of CD3-negative MNCs after depletion was 76% (range 52-100%). The mean recovery of CD34(+) stem cells in the four evaluable experiments was 82% (range 75-92%). In vitro colony assays and in vivo NOD/SCID repopulation assays showed that this large-scale T cell depletion method has no negative impact on the function of the hematopoietic precursor cells. Therefore, we conclude that this T cell depletion method is a valuable tool for further graft engineering strategies involving mobilized PBSCs.

[Indications, techniques and results of laparoscopic surgery for diaphragmatic diseases]. / Indikation, Technik und Ergebnisse der laparoskopischen Zwerchfellchirurgie.

Eleven patients with congenital, traumatic and functional extrahiatal diaphragmatic lesions are reported. Since 1991 two patients with acute, two patients with old ruptures of the diaphragm and one patient with a Morgagni-Larrey-hernia were successfully treated by laparoscopic direct suturing. In two other patients with Morgagni hernias we used a polypropylene mesh for closure of the defect. One procedure was performed in a patient with symptomatic congenital dysplasia of the diaphragm with aplasia of the pericard. Laparoscopic plication of the diaphragm was performed in three symptomatic patients with phrenic nerve palsy after cardiac surgery. The intra- and postoperative course was uneventful in all cases. During a median follow-up of 60 months there was no recurrence. Therefore the laparoscopic technique is an effective and attractive alternative for treatment of these diseases.

[Management of common bile duct stones--Results of a nationwide survey with analysis of 8 433 common bile duct explorations in Germany]. / Management der Choledocholithiasis - Umfrageergebnisse und Analyse von 8 433 Gallengangsrevisionen in Deutschland, Germany.

BACKGROUND: Aim of this study was the evaluation of the management of choledocholithiasis and outcome of laparoscopic as well as open cholecystectomy in Germany. METHODS: A written questionnaire was sent to 449 randomly selected German surgeons annually from 1991 to 1994 and additionally to all German university hospitals until 1998. RESULTS: A total of 98 482 operations for gallstone disease including 86 485 cholecystectomies (non-university hospitals 1991-1993: n = 60 246, university hospitals 1991-1996: n = 26 239) and 8 433 common bile duct (CBD) explorations (non-university hospitals: n = 6 919, university hospitals: n = 1 514) with or without cholecystectomy were reported. The overall complication rate for CBD explorations was 13.2 % (non-university hospitals) and 15.1 % (university hospitals), the overall hospital mortality rate was 0.64 % (non-university hospitals) and 0.58 % (university hospitals, n. s.). When choledocholithiasis was suspected, in 1998 all university hospitals used a two-stage management with preoperative ERC. In case of diagnosed isolated choledocholithiasis 93 % usually chose an endoscopic approach. When simultaneous cholecysto-choledocholithiasis was diagnosed preoperatively 86 % of the university hospitals used a two-stage management with preoperative ERC and stone extraction and secondary cholecystectomy (1991: 45 %). The percentage of CBD explorations decreased continuously from 7.4 % in 1991 to 3.8 % in 1996 (p < 0.01). CONCLUSION: These results allow for the estimation of frequency and overall risks in surgical therapy of CBD stones. At the moment, laparoscopic CBD exploration does not play a significant role in Germany. Data show a trend to the two-stage "therapeutical splitting" with lower complication rates.

Absence of D alloimmunization in D- pediatric oncology patients receiving D-incompatible single-donor platelets.

BACKGROUND: Guidelines are lacking for prophylaxis against D alloimmunization after D-incompatible platelet transfusion. A rational basis for the application of prophylaxis would be beneficial for institutions in which inventory constraints demand the administration of large numbers of D-incompatible platelets. STUDY DESIGN AND METHODS: A retrospective analysis was performed of all D-incompatible platelet transfusions administered at a pediatric research hospital over a 1.5-year period. Patients exclusively received single-donor WBC-reduced platelets and did not receive RhIg immunoprophylaxis. Numbers, source, ABO type, duration of serologic follow-up, and level of RBC contamination of D-incompatible transfusions were analyzed. All positive D serologies in the institution over a 3.5-year period were examined to determine cause and potential association with platelet transfusion. RESULTS: Thirty-five patients not receiving bone marrow transplant and seven bone marrow transplant patients received 490 and 255 D-incompatible transfusions, respectively, over 1.5 years. Patients had various diagnoses, predominantly malignancies. Seventy-nine percent of D-incompatible transfusions were ABO compatible. An estimated 2300 incompatible transfusions were performed over 3.5 years. No case of D alloimmunization was detected. CONCLUSIONS: D immunoprophylaxis is generally unnecessary in pediatric oncology patients receiving D-incompatible, WBC-reduced, single-donor platelets not visibly contaminated by RBCs. Further studies to validate these observations in the pediatric population and to extend them to other population groups are warranted.

Integrated src kinase and costimulatory activity enhances signal transduction through single-chain chimeric receptors in T lymphocytes.

Adoptive immunotherapy using receptor-modified T lymphocytes has shown promise in preclinical studies for the treatment of infectious and malignant diseases. These modified T cells express chimeric receptors that link ligand recognition and signal transduction domains in a single gene product. Typically, a single chain Fv fragment is genetically attached to the cytoplasmic domain of the T-cell receptor (TCR) zeta chain. Modulating the signaling characteristics of chimeric receptors will be important for their application to human immunotherapy. It was hypothesized that linking coreceptor and costimulatory signaling motifs together with the zeta signaling domain will enhance receptor function. The present study compares signaling characteristics of 9 single-chain receptors consisting of the H-2K(b) extracellular and transmembrane domains and various combinations of T cell signal transduction domains. Signal transduction regions studied include the TCR zeta chain, the CD4 coreceptor, the lck protein tyrosine kinase, and the CD28 costimulatory receptor. Biochemical characteristics of the receptors, analyzed using calcium flux, receptor, and ZAP-70 phosphorylation, and lck association may be predicted from the known functions of receptor constituents. The combination of zeta together with coreceptor and costimulatory function in a single receptor maximizes chimeric receptor sensitivity and potency. Combining zeta with either the costimulatory or coreceptor function independently also enhances receptor function, though to a lesser extent. It is therefore possible to link TCR, coreceptor, and costimulatory activities in a single functional entity using modular domains. Such receptors demonstrate distinct signaling properties and should prove useful in the development of chimeric receptors for therapeutic purposes.