Optimization of an elispot assay to detect cytomegalovirus-specific CD8+ T lymphocytes

Various arguments suggest that CD8+ T lymphocytes play a major role in the control of cytomegalovirus (CMV) infection. The detection of CMV-specific CD8+ T cells may therefore provide additional information about CMV virus detection to predict the risk of development of CMV disease, especially in immunodepressed transplant recipients. We compared and tested various experimental conditions to optimize an enzyme-linked immunospot assay (Elispot) assay for the detection of CMV-specific CD8+ T lymphocytes. The indirect Elispot assay with one six-day in vitro sensitization step was found to be the most sensitive method to detect CMV-specific CD8+ T cells compared to direct Elispot with unfractionated peripheral blood mononuclear cells or purified CD8+ T cells. We showed that low doses of interleukin-2 during the in vitro culture enhanced the sensitivity of this test, and tetramer staining was performed to verify the high efficiency of this in vitro stimulation step. We directly loaded the specific CMV peptide during the Elispot assay and demonstrated that the use of T2 cells did not improve its sensitivity. Elispot for the detection of interferon-gamma appears to be more sensitive and reliable than measurement of tumor necrosis factor alpha or granzyme B. This technique was successfully applied to detect CMV-specific CD8+ T cells in human leukocyte antigen A2 (HLA-A2) and HLA-B7 healthy patients and in one lymphopenic post-transplant patient with positive CMV serology. This highly sensitive test may be a useful tool to assess T-cell immunity directed against CMV in immunodepressed patients.     

Cytogenetic analysis of a mesenchymal hamartoma of the liver

Cytogenetic analysis of a mesenchymal hamartoma of the liver in a 3-year-old child revealed a balanced translocation between chromosomes 15 and 19 as the sole chromosome change.     

Demonstration of complex dysregulation of anti-cytomegalovirus T-cellular immunity in Kaposi's sarcoma following renal transplantation

An increased incidence of Kaposi's sarcoma is well known in renal transplant recipients in whom it may represent up to 3 p. 100 of all de novo tumours. This sarcoma has a close relationship with the potential oncogenicity of the cytomegalovirus (CMV) and with chronic immunological deficiency. Anti-CMV immunity is based on the integrity of cytotoxic cellular functions such as those of cytotoxic T lymphocytes (CTL), "natural killers" cells, and K cells which function in the antibody-dependent cell cytotoxicity (ADCC) system. Two cases of Kaposi's sarcoma were observed out of a total of 700 renal transplant recipients; they underwent the following investigations: lymphocyte sub-group counts by murine monoclonal antibodies, lymphocyte proliferation to lectins and allogenic cells, NK activity and generation of specific auxiliary and cytotoxic anti-CMV cells. Both cases of Kaposi's sarcoma were seropositive for CMV and seronegative for LAV. In one case, an abnormal number of peripheral OKT9 + lymphocytes (normally a thymocytic marker) was observed with small numbers of OKT4/OKT8, a reduced proliferative response to mitogens and allogenic cells. All these in vitro changes persisted despite reduction of immunosuppressive therapy and clinical improvement. A clinical and biological cure was only obtained after withdrawal of immunosuppressive therapy and return to haemodialysis. In the second case of Kaposi's sarcoma, the initial biochemical changes were minimal and a clinical cure was obtained by decreasing the immunosuppressive therapy. These two cases illustrate the complex dysregulation of the immune system in Kaposi's sarcoma.     

Recurrent cystitis and crenotherapy. 302 cases

This article analyzes a series of 302 female patients prone to cystitis. The fact that these women were seen in a urological crenotherapy center highlights the very evolutive nature of the disease. The high rate of E coli present in the urine should be noted. Most of the women had a normal intravenous urogram and a normal endoscopy. The "classic" causes are rarely responsible for attacks of cystitis, but sexual intercourse and pregnancy seem to play a part. Several of the women took estroprogestative pills, or wore an intra-uterine device. The rate of bowel symptomatology-colopathy or constipation--should be noted. The article assesses the evolution of cystitis before and after crenotherapy at La Preste.     

Treatment of malignant gliomas in adults with BCNU plus metronidazole

Summary Twenty-six adult patients with astrocytomas were treated with BCNU (1,3-bis(2-chloroethyl)-1-nitrosourea) 180–240 mg/m² 1.V. every 6–9 weeks, with metronidazole 1.5 g/m² p. o. 12 h and 1 h before BCNU and again 6 h and 24 h after BCNU. Of twenty-two evaluable patients, 9 (41%) responded with evidence of reduced tumor size on CT scan, 3 (14%) stabilized and 10 (45%) failed. Patients with no prior chemotherapy or radiotherapy, good performance. status, low grade tumors, and age 50 years had the highest response rates, although differences were not statistically significant. Median survival and duration of response have not been reached with a median follow-up time of ten months. Hematological toxicity was dose-limiting and was probably not augmented by the metronidazole. There was one death from infection that was possibly drug-related. Gastrointestinal toxicity was substantial, and was probably increased by the metronidazole.While the combination of BCNU and metronidazole were tolerable, the response rate seen was no higher than that noted for BCNU alone, and further studies using this dose-schedule are not recommended in astrocytomas.Presented at the 13th International Congress of Chemotherapy, Vienna Austria, August 1983.     

Are video display terminals a source of increased PCB concentration in the working atmosphere?

Summary In response to the question: Are datascreen terminals a source of increased PCB concentrations in the working atmosphere? a study of PCB emissions from video display terminals (VDT) was undertaken. Emissions of 2.4 to 8.1 ng PCB/h were observed from VDT located in a building (1) where the mean PCB level in the air was 46 ng PCB/m³ during the test period, whereas no PCB emissions were detected from VDT located in a building (2) where no PCB could be detected in the ambient air. However, both the air and the VDT from building 2 were found to be contaminated with polycyclic aromatic hydrocarbons. We conclude that the observed PCB emissions from VDT are the result of the vapourization of PCB deposited onto the VDT from the PCB contaminated air and do not originate from the electrical components of the VDT.     

Exon identity influences splicing induced by exonic variants and in silico prediction efficacy

BackgroundMinigenes and in silico prediction tools are commonly used to assess the impact on splicing of CFTR variants. Exon skipping is often neglected though it could impact the efficacy of targeted therapies. The aim of the study was to identify exon skipping associated with CFTR variants and to evaluate in silico predictions of seven freely available software.MethodsCFTR basal exon skipping was evaluated on endogenous mRNA extracted from non-CF nasal cells and on two CFTR minigene banks. In silico tools and minigene systems were used to evaluate the impact of CFTR exonic variants on exon skipping.ResultsData showed that out of 65 CFTR variants tested, 26 enhanced exon skipping and that in silico prediction efficacy was of 50%-66%. Some in silico tools presented predictions with a bias towards the occurrence of splicing events while others presented a bias towards the absence of splicing events (non-detection including true negatives and false negatives). Classification of exons depending on their basal exon skipping level increased prediction rates up to 80%.ConclusionThis study indicates that taking basal exon skipping into account could orientate the choice of the in silico tools to improve prediction rates. It also highlights the need to validate effects using in vitro assays or mRNA studies in patients. Eventually, it shows that variant-guided therapy should also target exon skipping associated with variants.     

Optimal donation of kidney transplants after controlled circulatory death

Controlled donation after circulatory death (cDCD) is used for “extended criteria” donors with poorer kidney transplant outcomes. The French cDCD program started in 2015 and is characterized by normothermic regional perfusion, hypothermic machine perfusion, and short cold ischemia time. We compared the outcomes of kidney transplantation from cDCD and brain-dead (DBD) donors, matching cDCD and DBD kidney transplants by propensity scoring for donor and recipient characteristics. The matching process retained 442 of 499 cDCD and 809 of 6185 DBD transplantations. The DGF rate was 20% in cDCD recipients compared with 28% in DBD recipients (adjusted relative risk [aRR], 1.43; 95% confidence interval [CI] 1.12–1.82). When DBD transplants were ranked by cold ischemia time and machine perfusion use and compared with cDCD transplants, the aRR of DGF was higher for DBD transplants without machine perfusion, regardless of the cold ischemia time (aRR with cold ischemia time <18 h, 1.57; 95% CI 1.20–2.03, vs aRR with cold ischemia time ≥18 h, 1.79; 95% CI 1.31–2.44). The 1-year graft survival rate was similar in both groups. Early outcome was better for kidney transplants from cDCD than from matched DBD transplants with this French protocol.