Plateletpheresis Donors Research Articles

Identification of new bioactive molecules in platelet preparation, storage, and transfusion reactions for improved transfusion management

Platelet concentrates (PCs) intended for transfusion contain bioactive molecules that can be considered Biological Response Modifiers (BRMs), mainly originating from plasma regardless of the preparation process. During storage, NGAL and GDF-15 levels increase in single donor apheresis platelet concentrates (SDA-PC), whereas in buffy coat platelet concentrates (BC-PC), the levels of MIP1α, MCP-3, and HSAA increase, and GDF-15 levels decrease. These molecules, primarily released by leukocytes, may contribute to adverse reactions (ARs) following a PC transfusion. Notably, in SDA-PC or BC-PC transfusions that result in ARs, the levels of NGAL, HSAA, and GDF-15 are significantly elevated, while the levels of MDC and CX3CL1 are significantly reduced compared to transfusions without ARs. These biomarkers could potentially serve as predictors for PCs-induced ARs.

Increased platelet-leucocyte complexes do not result in coagulation activation in plateletpheresis donors.

Although plateletpheresis donation is commonly accepted as a safe procedure, its influence on platelet function, coagulation system and fibrinolysis is not completely elucidated. In this study, we tried to assess the effects of plateletpheresis on donor's hemostasis system by measuring platelet activation, development of platelet-leukocyte aggregates, and coagulation activation. Prospective observational study. We used flow cytometry to determine the levels of platelet-monocyte complexes (PMC) and platelet-neutrophil complexes (PNC). sP-selectin and prothrombin fragment (PF) 1 + 2 values were determined by ELISA. The PMC levels increased significantly seven days after apheresis in comparison with just after apheresis and 24 h after apheresis (p < 0.05). The PNC levels increased significantly seven days after apheresis compared to immediately after apheresis (p < 0.05). sP-selectin values decreased significantly immediately after apheresis (p < 0.05). While sP-selectin values increased seven days after apheresis in comparison with immediately after apheresis and 24 h after apheresis, but there were not statistically significant differences for sP-selectin levels (p > 0.05). PF1 + 2 levels decreased significantly immediately after apheresis compared to pre-apheresis (p < 0.05) and increased 24 h after apheresis and seven days after apheresis, but these differences were not statistically significant. We concluded that plateletpheresis affects platelet activation but does not cause any change in coagulation activation.

Analysis of changes in serum calcium and magnesium levels during plateletpheresis on different apheresis machines in healthy donors: A cross-sectional study

Abstract: BACKGROUND: The most common observed complication of plateletpheresis procedure is hypocalcemia due to citrate’s chelation of free calcium. Magnesium is also affected by citrate infusion. We have evaluated the impact of plateletpheresis on the total serum calcium (Ca++) and magnesium (Mg++) levels of the donor. MATERIALS AND METHODS: One hundred and thirty-seven healthy plateletpheresis donors were included in the study. Samples were collected from the donor at 0 min (baseline), 30 min, and 60 min, at the end of the procedure and 30 min after completion of the procedure. The pattern of changes in serum Ca++ and serum Mg++ levels at different time points for different apheresis machines (Fenwal Amicus, Fresenius COM.TEC, Spectra Optia, and Hemonetics MCS+) was studied. RESULTS: A significant decline in serum Ca++ and serum Mg++ levels from baseline to the end of the procedure was observed. This decline was observed maximum for Hemonetics MCS+. The baseline values were regained 30 min after completion of the procedure. Difference from baseline values 30 min after the procedure was lowest in amicus in the case of serum Ca++ and COM.TEC in case of serum Mg++. Twenty donors (14.60%) experienced adverse donor reactions. CONCLUSION: Serum calcium and serum magnesium levels decreased transiently during the procedure and regained normal values after 30 min of the completion of the plateletpheresis procedure on all four apheresis machines (whether based on continuous or intermittent centrifugation). Hence, it is concluded from our study that plateletpheresis is a well-tolerated and safe procedure.

The Diagnostic Value of Ret-He in Predicting Latent Iron Deficiency in Female Blood Donors

To explore the application value of reticulocyte hemoglobin equivalent (Ret-He) for diagnosing latent iron deficiency in female plateletpheresis donors. A total of 230 female plateletpheresis donors in Fujian Blood Center from January to February 2022 were selected as the research group and divided into three groups: normal group, iron depletion (ID) group and iron deficient erythropoiesis (IDE) group, according to the severity of iron deficiency. The level of hemoglobin (HGB), mean corpuscular volume (MCV), mean corpuscular hemoglobin (MCH), coefficient of variation of red cell distribution width (RDW-CV) and Ret-He were measured by using the Sysmex XN automated hematology analyzer. Chemiluminescence immunoassay was used to detect iron biochemical indexes. Receiver operating characteristic(ROC) curve analysis was performed to evaluate the diagnosic value of relevant indicators in female blood donors with latent iron deficiency. Ret-He in ID group was 32.55 (31.15,33.10)pg, which was significantly lower than that in the normal group ［33.80(32.73，34.70)pg］ （P <0.05）, and significantly higher than that in IDE group ［30.40(28.70,31.50)pg］ （P <0.05）. ROC analysis in diagnosis of IDE demonstrated that the area under the curves (AUCs) of HGB, MCV, MCH, RDW-CV and Ret-He were 0.892, 0.843, 0.909, 0.890, 0.931, respectively. When the critical value of Ret-He was 32.05 pg, its sensitivity and specificity were 85.90% and 92.60%, respectively. However, all red blood cell parameters had poor diagnostic value for ID. Ret-He is a perfect predictor for latent iron deficiency in female blood donors. Detection of Ret-He can advance the diagnosis of iron deficiency in female blood donors to the IDE stage.

Analysis of erythrocyte and iron study data among plateletpheresis donors in Hangzhou, China

BackgroundThe purpose of this study is to obtain the iron parameters level of blood donors and the population who need to pay attention to iron parameters level in this area. MethodsA total of 993 plateletpheresis donors were included in this study, including 798 males and 195 females. The results of erythrocyte and iron parameters of blood donors were compared and analyzed in different groups according to the gender, age and number of blood donations. ResultThe proportion of men and women with low serum ferritin (SF) levels was 10.8 % and 27.7 %, respectively. The mean levels of serum iron (SI), SF, transferrin saturation (Tfs), hemoglobin (Hb) and hematocrit (HCT) of male blood donors decreased with the increase of age groups, but there was no significant statistical difference between the results of female blood donors. The level of SI, SF, Tfs, Hb and HCT of male donors decreased with the increase of blood donations in the past year, while TRF and TIBC increased. The level of Hb, HCT and SF of female donors showed no significant downward trend, while the levels of TRF increased with increasing donations in the past year, excluding first-time donors. The SI of female donors trended down, and TIBC trended up with increasing donations. ConclusionBlood collection institutions need to focus on iron parameters levels in older and frequent male donors, and young fertile female donors.

Impact of Mild SARS-CoV-2 Infection on Hematological Parameters and Suitability of Apheresis Platelets Donation in Blood Donors

To investigate the effects of mild SARS-CoV-2 infection on hematological parameters of adult blood donors and the suitability of apheresis platelet donation, the changes of the hematological parameters in blood donors with mild infection of the SARS-CoV-2 Omicron variant strain were evaluated. Seventy-two blood donors with mild COVID-19 symptoms who donated consecutive apheresis platelets for 3 times from December 2022 to January 2023, 42 cases among which were included in the infection-positive group, and 30 cases in the suspected infection group. Forty-two donors un-vaccinated against SARS-CoV-2, un-infected, and donated three consecutive apheresis platelets from October to November 2022 were included in the control group. The changes of blood routine testing in the positive group and the suspected infection group were retrospectively compared before (Time1) and after (Time2 and Time3) the onset of symptoms, three consecutive times (Time1, Time2, Time3) in the control group by repeated measures analysis of variance. The Bayesian discriminant method was used to establish a discriminant equation to determine whether the recent infection of SARS-CoV-2 occurred or not. Simple effect of the number times of tests in the positive and suspected infection groups was significant（ Finfection-positive group=6.98, P < 0.001, partial η2=0.79, Fsuspected infection group=4.31, P < 0.001, partial η2=0.70）. The positive group and the suspected infection group had lower RBC, HCT, and HGB, and higher PLT and PCT at Time2 compared to Time1 and Time3(P < 0.05). The positive group and the suspected infection group showes RDW-CV and RDW-SD at Time3 higher than Time1 and Time2 (P < 0.001). The simple effect of the number times of tests in the control group was not significant ( F=0.96, P =0.55, partial η2=0.34). The difference of the whole blood count parameters in the control group for three times was not statistically significant (P >0.05). We established a discriminant equation to determine whether the recent infection of SARS-CoV-2 occurred or not. The equation had an eigenvalue of 0.22, a canonical correlation of 0.43 (χ2=27.81, P < 0.001), and an analysis accuracy of 72.9%. The hematological indicators of RBC, HCT, HGB, PLT, PCT, RDW-CV and RDW-SD in blood donors who had infected with mild COVID-19 showed dynamic changes. The discriminant equation for whether they are infected recently with COVID-19 has a high accuracy rate.

Discussion on the recruitment strategy for apheresis platelet donors in Chongqing during a public health emergency.

This study aimed to analyze the population characteristics of apheresis platelet donors in Chongqing Province and provide a scientific basis for the development of precise and efficient recruitment strategies. The ultimate goal is to increase the number of regular platelet donors in preparation for public health emergencies. This study involved 53,089 blood donors who donated apheresis platelets to the Chongqing Blood Center from 2020 to 2022. Data regarding age, sex, blood type, education level, occupation, and frequency of blood donation were collected and analyzed to identify factors influencing platelet donation. Between 2020 and 2022, the majority of apheresis platelet donors in Chongqing were aged 25-35 years, with a male-to-female ratio of 2.6:1. The ABO blood group distribution was O > A > B > AB. The apheresis platelet donors mainly consisted of college students, and the donors who had donated only once accounted for the greatest proportion. Based on the population characteristics of apheresis platelet donors in Chongqing, blood collection and supply organizations must refine emergency blood collection and supply plans during public health emergencies. This study underscores the importance of developing precise and efficient recruitment strategies for apheresis platelet donors and expanding the pool of regular apheresis platelet donors. These measures are essential to ensure the timely, safe, and effective use of clinical blood resources during public health emergencies.

Establishment and clinical application of the HLA genotype database of platelet-apheresis donors in Suzhou

The establishment of a platelet-apheresis donor database may provide a feasible solution to improve the efficacy of platelet transfusion in patients with immune platelet transfusion refractoriness (PTR). This study aimed to establish HLA genotype database in Suzhou, to provide HLA-I compatible platelets for PTR patients to ensure the safety and effectiveness of platelet transfusions. We used a polymerase chain reaction sequence-based typing (PCR-SBT) method to establish the database by performing high-resolution HLA-A, -B, and –C genotyping on 900 platelet-apheresis donors. HLA-I antibody was detected in patients using a Luminex device, and HLA-I gene matching was performed by an HLA-Matchmaker. We found that the highest frequency of the HLA-A allele was A*11:01 (17.06 %), followed by A*24:02 (14.67 %) and A*02:01 (13.61 %). The highest frequency of the HLA-B allele was B*46:01 (9.78 %), followed by B*40:01 (8.39 %) and B*13:02 (33 %). After the detection of platelet antibodies in 74 patients with immune PTR, we found 30 HLA-A antibodies and 48 HLA-B antibodies, and there were a variety of high frequency antibodies whose alleles were low in the donor database, such as HLA-A*68:02, and B*57:01. After avoiding donor-specific antibodies (DSA) matching, 102 of 209 platelet-compatible transfusions were effective, resulting in an effective rate of 48.8 %, which significantly improved the efficacy of platelet transfusion. The establishment of a platelet donor database is of great significance to improve the therapeutic effect of platelet transfusion in patients with hematologic disorder, and save blood resources, and it is also the premise and guarantee of precise platelet transfusion.

Full annotation of viral metagenomics in different components from Chinese blood donors using next-generation sequencing.

Emerging viruses in the blood of healthy/qualified donors can seriously affect transfusion safety. However, the virus characteristics in different healthy blood donors and blood components are still not fully understood. Buffy coat (BC) and plasma specimens were collected from 32 whole blood donors, and platelet (PLT) and BC specimens from 30 apheresis platelet donors to explore the full annotation of viral metagenomics in different blood components from Chinese blood donors using next-generation sequencing technology. The study detected 56 viruses in the plasma and BC groups of whole blood donors. The plasma group had a significantly higher viral abundance and more types of viruses than the BC group. We detected 20 viruses in the PLT and BC groups of apheresis platelet donors. Viral abundance and types were significantly lower in the BC group than in the PLT group. According to β-diversity analysis, the plasma group had a significantly different community structure and composition than the BC group. Viral nucleic acid is found in the blood of healthy Chinese blood donors, with the highest concentration in plasma, which could explain the distribution of viruses in the blood of healthy individuals.

Donor complication rates in whole blood, plasma and platelet donors: Age versus experience.

Many blood banks use upper age limits for donors out of concern for a higher donor complication rate in older donors. Experienced donors are known to have lower donor complication rates, and older donors are often more experienced, confounding the effect of age on donor complication rate. We studied donor complication rates in whole blood, plasma, and plateletpheresis donors from 2012 to 2022. Donor complication rates were compared between age groups in inexperienced (<20th donation) and experienced (≥20th donation) donors. In addition to this direct comparison, we made use of logistic regression with finer-grained experience groups, to further quantify the effects of age, experience and other factors on donor complication rate. While overall rate of vasovagal reaction was lower, rate of moderate/severe vasovagal syncope was highest in 70-79 year donors, however, only reached significance for plasma donors. Furthermore, rates of failed stab were highest in this age group. Hematoma rate showed a U-shaped pattern with regard to age, where the rate was not higher in the 70-79 year age group than in the 18-23 year age group. Pain decreased with age, however, rates were higher in the 70-79 year age group than in the 65-69 year age group. When properly accounting for donor experience, donor complication rate profiles clearly change with age. The increased risk for moderate/severe vasovagal syncope in older donors should be clearly communicated. Extra caution is needed if these donors are accepted for first-time donations.

Donors with repeated blood product discards for filtration problems, clots or hemolysis: Causes and follow-up.

Sanquin donor medicine department is informed when donations or their components are rejected. This can occur isolated or frequently. It is undesirable because the donations cannot be used and there may be an underlying medical cause. Based on regional approaches, a uniform procedure was developed. Information about whole blood, plasma- plateletpheresis donations from which one or more components were rejected for filtration time (>2 h), hemolysis or clots were extracted from blood bank information system. After rejection of two successive components or donations or total ≥3 the donor is contacted. Depending on the medical history and investigation by the family doctor, the donor carrier is re-evaluated. We looked for the causes of the discarded products and performed a survey among blood services regarding polices with discarded products. One or more components from 1742 of about 2.2 million successful donations (0.08%) were rejected. The highest percentage of rejection was seen in plateletpheresis (1.5%), all for clots. No underlying medical causes were found. 24 whole blood donors were found to have sickle cell trait (SCT) and were permanently deferred. The policies for follow-up after discarded products or acceptance of SCT donors vary between the 16 blood banks. Six organizations do not follow-up donors and seven accept SCT for blood or plasma donation. Informing donors with repeated discarded products avoids the non-use of donations. Causes of repeated discarded products can be found by follow-up of donors. The results of the survey indicate a large discrepancy in policies applied worldwide.

Determinants of Variable Total Platelet Count in Healthy Plateletpheresis Donor.

The platelet count in a healthy individual varies between 150 and 450 × 109/L. This study explores the factors affecting this variation in platelet count in healthy blood donors selected for platelet donation. This retrospective study comprises an analysis of platelet donor data between the year 2016-2022. The pre-recorded donor details such as age, gender, blood group, body mass index (BMI), and complete blood counts were collected and analyzed using the software 'R' (version 4.1.0). The statistical analysis consists of a test of normalcy followed by descriptive details and advanced statistics such as correlation and regression analysis to predict the variables affecting platelet count. The p-value of less than 0.05 was taken as significant. The median (IQR) of hemoglobin, platelet count, and total leucocyte count (TLC) was 142(135-150) g/L, 239(204-285) × 109/L, and 7.6(6.4-8.8) × 109/L, respectively. The platelet count was positively correlated with TLC (p = 0.000) and negatively with the age of the platelet donor (p = 0.001). The Kruskal-Wallis test detected significant differences in the platelet count among the ABO blood group (p = 0.008). Further, regression analysis confirms the independent positive association of total platelet count with the total leucocyte count (p = 0.000) and the negative association of platelet count with age (p = 0.004). This study concludes the strong dependency of total platelet count with total leucocyte count, age, and blood group.

Development of a highly cytotoxic, clinical-grade virus-specific T cell product for adoptive T cell therapy

At present, recipients of allogeneic hematopoietic stem-cells are still suffering from recurrent infections after transplantation. Infusion of virus-specific T cells (VST) post-transplant reportedly fights several viruses without increasing the risk of de novo graft-versus-host disease. This study targeted cytomegalovirus (CMV) for the development of an innovative approach for generating a very specific VST product following Good Manufacturing Practices (GMP) guidelines.We used a sterile disposable compartment named the Leukoreduction System Chamber (LRS-chamber) from the apheresis platelet donation kit as the starting material, which has demonstrated high levels of T cells. Using a combination of IL-2 and IL-7 we could improve expansion of CMV-specific T cells. Moreover, by developing and establishing a new product protocol, we were able to stimulate VST proliferation and favors T cell effector memory profile. The expanded VST were enriched in a closed automated system, creating a highly pure anti-CMV product, which was pre-clinically tested for specificity in vitro and for persistence, biodistribution, and toxicity in vivo using NOD scid mice. Our results demonstrated very specific VST, able to secrete high amounts of interferon only in the presence of cells infected by the human CMV strain (AD169), and innocuous to cells partially HLA compatible without viral infection.

T-cell lymphopenia in frequent volunteer platelet donors.

In the United States, more than 2 000 000 apheresis platelet units are collected annually from volunteer donors. Platelet donors in the United States and elsewhere are permitted to donate up to 24 times per year. Recently, frequent apheresis platelet donation has been associated with severe T-cell lymphopenia. Several frequent platelet donors have been found to have peripheral blood CD4+ T-cell counts below 200 cells/µL, the threshold for AIDS in HIV-positive individuals. Independent risk factors for plateletpheresis-associated lymphopenia include lifetime donations, age, and donations on the Trima Accel instrument (Terumo BCT), which uses a leukoreduction system (LRS) chamber to trap white blood cells. Less often, severe lymphopenia can occur in donors collected on the Fenwal Amicus instrument (Fresenius Kabi), which has no LRS. For Trima Accel donors, lymphopenia can be partially mitigated by performing a plasma rinseback step at the end of collection. To date, there is no definitive evidence that plateletpheresis-associated lymphopenia is harmful. In a study of frequent platelet donors with lymphopenia who were administered COVID-19 messenger RNA vaccines, immune responses were normal. The homeostatic mechanisms responsible for maintaining a normal peripheral blood T-cell count remain obscure, as do the causal mechanisms underlying plateletpheresis-associated lymphopenia.

Adverse Events Among Plateletpheresis Donors in a Tertiary Care Hospital at Dhaka, Bangladesh

Introduction: The rising demand for platelet transfusions among patients has increased the usage of automated blood collections. Many of the same reactions and injuries are found with pooled platelets received from whole blood donation, although notable differences exist. Objective: To study the adverse events (AEs) during plateletpheresis procedures in a tertiary care hospital and plateletpheresis procedure session profiles. Materials and Methods: This retrospective study was conducted from January 2021 to December 2021 by analyzing records of two-hundred and thirteen (213) plateletpheresis procedures done in transfusion medicine department. All the donors were male. All adverse effects were recorded and noted in the registrar. Results: A total of 13 (Thirteen) AEs were noted, of which 08 (61.53%) events were associated with donors, 03 (23.07 %) were owed to a fault in the kit/equipment, and 02 (15.38 %) were due to technical faults. Donor-related AEs included hematoma (23.07%), vasovagal (23.07%), and perioral tingling sensation (15.38%). Technique-related AEs were 23.07%, and faulty kit/equipment-related AEs were 15.38%. Conclusion: Apheresis donations performed on apheresis machines are safe. Careful donor selection, well-trained expert technical personnel, and supervision of experienced transfusion medicine specialists will make the donor’s experience more pleasant. Sir Salimullah Med Coll J 2023; 31: 67-72

P‐BB‐68 | Reference Ranges for Complete Blood Count in Platelet Apheresis Donors at an Intermediate Altitude

P‐BB‐68 | Reference Ranges for Complete Blood Count in Platelet Apheresis Donors at an Intermediate Altitude

P‐BB‐35 | Evaluating Thrombocytosis in Apheresis Platelet Donors

P‐BB‐35 | Evaluating Thrombocytosis in Apheresis Platelet Donors

Relationship between Iron Metabolic Parameters and Platelet Counts in Blood Donors

To investigate the correlation of iron metabolic parameters with platelet counts in blood donors. A total of 400 blood donors who met requirements of apheresis platelet donation were collected, and their hematological parameters were analyzed. The donors were divided into low ferritin group and normal group, the differences of hematological parameters between the two groups were compared, and the correlation of iron metabolic parameters and routine hematology parameters with platelet counts were analyzed. Whether male or female, low ferritin group had higher platelet counts than normal group (P < 0.01). Among the iron metabolic parameters, the platelet counts was negatively correlated with serum ferritin (SF), serum iron (SI), and transferrin saturation (TSAT) (r =-0.162, r =-0.153, r =-0.256), and positively correlated with total iron binding capacity (TIBC) and unsaturated iron binding capacity (UIBC) (r =0.219, r =0.294) in female blood donors. Platelet counts was also negatively correlated with SF, SI and TSAT (r =-0.188, r =-0.148, r =-0.224) and positively correlated with UIBC (r =0.220) in male blood donors. Among the routine hematology parameters, platelet counts was negatively correlated with mean corpuscular volume (MCV), mean corpuscular hemoglobin (MCH), mean corpuscular hemoglobin concentration (MCHC), and reticulocyte hemoglobin equivalent (Ret-He) in female blood donors (r =-0.236, r =-0.267, r =-0.213, r =-0.284). Platelet counts was also negatively correlated with MCH, MCHC and Ret-He in male blood donors (r =-0.184, r =-0.221, r =-0.209). In blood donors with low C-reactive protein level, the lower the iron store capacity, the lower the iron utilization, and the platelet counts tends to rise.

'Ironing out the risk': Assessing the effect of plateletpheresis donation frequency on iron stores in South-Asian male donors.

Repeated blood donation is a well-known cause of iron deficiency among donors. However, present scientific literature lacks comprehensive evidence regarding the impact of regular plateletpheresis procedures on body iron reserves. In this study, we aimed to detect and correlate iron deficiency (using iron indices) with the frequency of platelet donations. Additionally, we also analysed the correlation between other iron and haematological indices with serum ferritin to determine cost-effective parameters that may serve as an initial screening approach to determine which donors should be subjected to serum ferritin testing. A total of 180 male participants from our platelet donor registry were enrolled in this observational cross-sectional study. Enrolment questionnaires were administered to eligible donors, and biological samples were collected during plateletpheresis donation. Biological tests such as complete blood count, reticulocyte indices, iron indices, vitamin B12 and folate were performed. Donors with ≥12 donations per year showed the highest prevalence of low ferritin (serum ferritin: 15-30 ng/mL) and absent iron stores (serum ferritin <15 ng/mL) (41.3% and 26.7%, respectively). Ferritin showed a significant negative correlation with recent (r = -0.346) and lifetime donations (r = -0.196). The efficacy of other indices for identifying iron depletion was much better using a serum ferritin value <15 ng/mL. Regular plateletpheresis donations can lead to varying severities of non-anaemic iron deficiency. Blood centres must regularly monitor frequent plateletpheresis donors (especially donors with more than 11 donations in a calendar year) and ideally maintain their serum ferritin above 30 ng/mL.

Efficient Chimeric Antigen Receptor T-Cell Generation Starting with Leukoreduction System Chambers of Thrombocyte Apheresis Sets

Introduction: Primary human blood cells represent an essential model system to study physiology and disease. However, human blood is a limited resource. During healthy donor plateletpheresis, the leukoreduction system chamber (LRSC) reduces the leukocyte amount within the subsequent platelet concentrate through saturated, fluidized, particle bed filtration technology. Normally, the LRSC is discarded after apheresis is completed. Compared to peripheral blood, LRSC yields 10-fold mononuclear cell concentration. Methods: To explore if those retained leukocytes are attractive for research purposes, we isolated CD3+ T cells from the usually discarded LRSCs via density gradient centrifugation in order to manufacture CD19-targeted chimeric antigen receptor (CAR) T cells. Results: Immunophenotypic characterization revealed viable and normal CD4+ and CD8+ T-cell populations within LRSC, with low CD19+ B cell counts. Magnetic-activated cell sorting (MACS) purified CD3+ T cells were transduced with CD19 CAR-encoding lentiviral self-inactivating vectors using concentrated viral supernatants. Robust CD19 CAR cell surface expression on transduced T cells was confirmed by flow cytometry. CD19 CAR T cells were further enriched through anti-CAR MACS, yielding 80% CAR+ T-cell populations. In vitro CAR T cell expansion to clinically relevant numbers was achieved. To prove functionality, CAR T cells were co-incubated with the human CD19+ B cell precursor leukemia cell line Nalm6. Compared to unmodified T cells, CD19 CAR T cells effectively eradicated Nalm6 cells. Conclusion: Taken together, we can show that lymphocytes isolated from LRSCs of plateletpheresis sets can be efficiently used for the generation of functional CAR T cells for experimental purposes.