Investigation of product-derived lymphoma following infusion of piggyBac-modified CD19 chimeric antigen receptor T cells.

We performed a phase 1 clinical trial to evaluate outcomes in patients receiving donor-derived CD19-specific chimeric antigen receptor (CAR) T cells for B-cell malignancy that relapsed or persisted after matched related allogeneic hemopoietic stem cell transplant. To overcome the cost and transgene-capacity limitations of traditional viral vectors, CAR T cells were produced using the piggyBac transposon system of genetic modification. Following CAR T-cell infusion, 1 patient developed a gradually enlarging retroperitoneal tumor due to a CAR-expressing CD4+ T-cell lymphoma. Screening of other patients led to the detection, in an asymptomatic patient, of a second CAR T-cell tumor in thoracic para-aortic lymph nodes. Analysis of the first lymphoma showed a high transgene copy number, but no insertion into typical oncogenes. There were also structural changes such as altered genomic copy number and point mutations unrelated to the insertion sites. Transcriptome analysis showed transgene promoter-driven upregulation of transcription of surrounding regions despite insulator sequences surrounding the transgene. However, marked global changes in transcription predominantly correlated with gene copy number rather than insertion sites. In both patients, the CAR T-cell-derived lymphoma progressed and 1 patient died. We describe the first 2 cases of malignant lymphoma derived from CAR gene-modified T cells. Although CAR T cells have an enviable record of safety to date, our results emphasize the need for caution and regular follow-up of CAR T recipients, especially when novel methods of gene transfer are used to create genetically modified immune therapies. This trial was registered at www.anzctr.org.au as ACTRN12617001579381.

Fetal RHD Genotyping Using Real-Time Polymerase Chain Reaction Analysis of Cell-Free Fetal DNA in Pregnancy of RhD Negative Women in South of Iran.

BACKGROUND: Maternal-fetal RhD antigen incompatibility causes approximately 50% of clinically significant alloimmunization cases. The routine use of prophylactic anti-D immunoglobulin has dramatically reduced hemolytic disease of the fetus and newborn. Recently, fetal RHD genotyping in RhD negative pregnant women has been suggested for appropriate use of anti-D immunoglobulin antenatal prophylaxis and decrease unnecessary prenatal interventions. MATERIALS AND METHODS: In this prospective cohort study, in order to develop a reliable and non-invasive method for fetal RHD genotyping, cell free fetal DNA (cffD- NA) was extracted from maternal plasma. Real-time quantitative polymerase chain reaction (qPCR) for detection of RHD exons 7, 5, 10 and intron 4 was performed and the results were compared to the serological results of cord blood cells as the gold standard method. SRY gene and hypermethylated Ras-association domain family member 1 (RASSF1A) gene were used to confirm the presence of fetal DNA in male and female fetuses, respectively. RESULTS: Out of 48 fetuses between 8 and 32 weeks (wks) of gestational age (GA), we correctly diagnosed 45 cases (93.75%) of RHD positive fetuses and 2 cases (4.16%) of the RHD negative one. Exon 7 was amplified in one sample, while three other RHD gene sequences were not detected; the sample was classified as inconclusive, and the RhD serology result after birth showed that the fetus was RhD-negative. CONCLUSION: Our results showed high accuracy of the qPCR method using cffDNA for fetal RHD genotyping and implicate on the efficiency of this technique to predict the competence of anti-D immunoglobulin administration.

Evaluation of a Modified DNA Extraction Method for Isolation of Cell-Free Fetal DNA from Maternal Serum.

BACKGROUND: Discovery of short cell free fetal DNA (cffDNA) fragments in maternal plasma has created major changes in the field of prenatal diagnosis. The use of cffDNA to set up noninvasive prenatal test is limited due to the low concentration of fetal DNA in maternal plasma therefore, employing a high efficiency extraction method leads to more accurate results. The aim of this study was to evaluate the efficiency of Triton/Heat/Phenol (THP) protocol in comparison with the QIAamp DNA Blood mini Kit for cffDNA purification. METHODS: In order to evaluate the efficiency of THP protocol, DNA of Rhesus D (RhD) negative pregnant women's plasma was collected, then real-time PCR for RHD exon 7 was performed. The Ct value data of real time PCR obtained by two different methods were compared and after delivery serology test on cord blood was done to validate the real time PCR results. RESULTS: The results indicated significant differences between two extraction methods (p=0.001). The mean±SD of Ct-value using THP protocol was 33.8±1.6 and 36.1±2.47 using QIAamp DNA Blood mini Kit. CONCLUSION: Our finding demonstrated that THP protocol was more effective than the QIAamp DNA Blood mini Kits for cffDNA extraction and lead to decrease the false negative results.

G22A Polymorphism of Adenosine Deaminase and its Association with Biochemical Characteristics of Gestational Diabetes Mellitus in an Iranian Population.

Adenosine deaminase (ADA) is an important regulator of insulin action. The single nucleotide polymorphism (SNP) G22A in the ADA gene decreases enzymatic activity of ADA. The aim of this study was to investigate the relationship between the SNP G22A and blood glycemic control, insulin resistance, and obesity of gestational diabetes mellitus (GDM) patients in an Iranian population. SNP G22A was determined in women with GDM (N=70) and healthy pregnant women (control, N=70) using polymerase chain reaction-restriction fragment length polymorphism. Fasting plasma glucose (FPG), hemoglobin A1C (HbA1c), plasma insulin levels and plasma lipids were measured using commercial kits. Homeostasis model of assessment for insulin resistance (HOMA-IR) was calculated. The distribution of genotypes and alleles among GDM patients was similar to that of the control group. FPG and HbA1c were significantly higher in GDM patients with GG genotype compared with GDM patients with GA+AA genotype and non-GDM patients. The frequency of GG genotype was significantly higher in obese GDM patients compared to lean GDM patients. The SNP G22A in the ADA gene was not associated with the risk of GDM in our population. GG genotype was associated with poor glycemic control and obesity in GDM patients.

Relationship between AHSP gene expression, ß/α globin mRNA ratio, and clinical severity of the ß-thalassemia patients.

BACKGROUND: Alpha hemoglobin stabilizing protein (AHSP) is a chaperone-like molecule specialized for erythroid series which binds to free α-globin chain. According to this characteristic, AHSP can be considered an important factor which reduces beta thalassemia symptoms. MATERIALS AND METHODS: Reticulocytes RNA extraction and a subsequent cDNA synthesis were performed, followed by Relative qRT-PCR for AHSP, alpha, and beta globin chain genes. The beta actin gene was used as an endogenous reference as well. The relationship between AHSP gene expression, disease severity, and the ß/α globin mRNA ratio was studied among different homozygote ß-thalassemia patients (mild, moderate and severe) and compared with minor thalassemia and the normal population. RESULTS: Analysis of the ß-globin/α-globin mRNA ratio has shown that disease severity enhanced with a decrease in this proportion. Evaluation of the correlation between AHSP gene expression and the average of the ß-globin/α-globin expression ratio indicated a significant but indirect relationship in considered groups. Our results demonstrated that the AHSP gene expression increases in accordance with augmentation of clinical symptoms. CONCLUSIONS: Although one of the main reasons for reduced clinical severity in homozygote ß-thalassemia can be the high level of AHSP gene expression as a chaperon molecule, our findings indicated that AHSP gene expression decreased in a mild category as compared to that in severe and moderate groups.

Evaluation of red cell membrane cytoskeletal disorders using a flow cytometric method in South iran.

OBJECTIVE: The diagnosis of hereditary red blood cell (RBC) membrane disorders, and in particular hereditary spherocytosis (HS) and Southeast Asian ovalocytosis (SAO), is based on clinical history, RBC morphology, and other conventional tests such as osmotic fragility. However, there are some milder cases of these disorders that are difficult to diagnose. The application of eosin-5'-maleimide (EMA) was evaluated for screening of RBC membrane defects along with some other anemias. We used EMA dye, which binds mostly to band 3 protein and to a lesser extent some other membrane proteins, for screening of some membrane defects such as HS. MATERIALS AND METHODS: Fresh RBCs from hematologically normal controls and patients with HS, SAO, hereditary elliptocytosis, hereditary spherocytosis with pincered cells, severe iron deficiency, thalassemia minor, and autoimmune hemolytic anemia were stained with EMA dye and analyzed for mean fluorescent intensity (MFI) using a flow cytometer. RESULTS: RBCs from patients with HS and iron deficiency showed a significant reduction in MFI compared to those from normal controls (p<0.0001 and p<0.001, respectively), while macrocytic RBCs showed a significant increase in MFI (p<0.01). A significant correlation was shown between mean corpuscular volume and MFI, with the exceptions of HS and thalassemia minor. CONCLUSION: Our results showed that the flow cytometric method could be a reliable diagnostic method for screening and confirmation, with higher sensitivity and specificity (95% and 93%, respectively) than conventional routine tests for HS patients prior to further specific membrane protein molecular tests.

Analysis of ß/α globin ratio by using relative qRT-PCR for diagnosis of beta-thalassemia carriers.

BACKGROUND: Current routine tests for premarital screening of ß-thalassemia carriers are not applicable for diagnosis of rare atypical minor ß-thalassemia cases. A more specialized laboratory evaluation for them is the measurement of ß/α chain synthesis ratio with the assistance of radioactive amino acids. This method is also no longer routinely accessible. Consequently it is required to establish a rapid, trouble-free, and reliable method that encompasses all the cases of ß-thalassemia carriers. Therefore we have determined ß/α-globin mRNA ratio by applying relative qRT-PCR in various ß-thalassemia patients. METHODS: Reticulocytes RNA extraction and subsequent cDNA synthesis were performed, followed by relative qRT-PCR for α- and ß-globin chain genes and ß-actin gene as an endogenous reference. ß/α-Globin gene ratio was then evaluated with the Pfaffl method. RESULTS: The mean of ß/α ratio was 0.99, 0.81, 0.69, and 0.69 for normal population, minor, intermediate, and major ß-thalassemia, respectively. Approximately 6% of cases with minor thalassemia RBC index and normal HbA2 and having a decreased ß/α ratio were located in the minor ß-thalassemia group. The mean of ß/α mRNA ratio in normal individuals and minor ß-thalassemia was significantly different with all other groups (P-value < 0.05). Nevertheless, there was no such association between ß/α mRNA ratio in major and intermediate ß-thalassemia. CONCLUSION: According to the significant differences achieved, no overlapping between minor ß-thalassemia and normal group, capability of diagnosing atypical minor ß-thalassemia, and accessibility of this technique, we can declare that this method could be suggested as a routine premarital screening test for ß-thalassemia carriers.

Gibbon ape leukemia virus transduction of peripheral blood CD34+-derived dendritic cells.

BACKGROUND: Dendritic cells (DCs) play a critical role in the immune response and are a candidate for immunotherapy in cancer. Since gibbon ape leukemia virus (GALV) transduction of CD34+ cells is reasonably efficacious, we assessed the efficacy of GALV transduction of CD34+ derived DCs as a possible approach to creating genetically modified DCs for immunotherapy. METHODS: Peripheral blood CD34+ cells were transduced with retroviruses obtained from the PG13/LN C8 cell line, with the neomycin gene as a marker gene. After prestimulation of hematopoietic cells for 24 hours with 10 ng/mL interleukin (IL)-3, 10 ng/mL IL-6, 100 ng/mL stem cell factor, 100 ng/mL granulocyte-macrophage colony stimulating factor and 8 Amicrog/mL protamine sulfate, the cells were cultured in a transforming media prior to differentiating into DCs by GM-CSF, TNF-a and IL-4. Immunophenotyping analyses for confirmation of the generated DCs, colony formation assay and PCR were done for the expression of neomycin gene in the transduced cells. RESULTS: Titration of viral vectors indicated a transduction efficiency of 1×10(5) CFU/mL. Transduction efficiency for the CD34+ cells transformed to DCs was 45% and 38% before and after DC differentiation, respectively. Additionally, a mean (SEM) of 26.9% (11.4%) and 41.4% (11.8%) of the genetically modified DCs were positive for CD86+ HLA-DR and CD1a+CD14, respectively CONCLUSION: This study showed that the majority of transduced CD34+ cells were successfully differentiated into cells identical to DCs according to morphology and immunophenotyping features, which could be a potential application in immunotherapy.