A phase I/II study of adoptive SARS-CoV-2-specific T cells in immunocompromised hosts with or at risk of severe COVID-19 infection.

BACKGROUND: Post-transplant or hematological cancer patients have a higher risk of mortality after infection with ancestral and early variants of severe acute respiratory syndrome (SARS)-CoV-2. Adoptive cell therapy (ACT) with virus-specific T cells (VSTs) could augment endogenous T cell immunity to avoid disease deterioration before viral clearance. METHODS: We established a third-party SARS-CoV-2-specific T cell (COVID-T) bank in 2020 (NCT04351659) using convalescent and/or vaccinated donors. In a phase I/II study (NCT04457726), 13 adult and pediatric patients, acutely positive for SARS-CoV-2 and predicted to have a high chance of mortality, were recruited from September 2021 to February 2022. Twelve patients received a single dose of COVID-T cells, matched on at least 1 HLA. RESULTS: A dose of either 75,000 or 150,000 IFN-γ+CD3+ cells/m2 SARS-COV-2-specific T cells did not cause cytokine release syndrome, acute respiratory distress syndrome, or graft-versus-host disease. In the 8 patients who had detectable donor SARS-COV-2-specific T cells after ACT, none progressed to severe disease or died with COVID-19. In contrast, among the other four patients without evidence of donor micro-chimerism, two died of COVID-19. CONCLUSIONS: Long-acting third-party VSTs from convalescent or vaccinated donors could be expediently produced and might be clinically useful in future pandemics, particularly before global vaccination is implemented.

A cost-effective strategy for selection of third-party donors for a virus-specific T-cell bank for an Asian patient population.

BACKGROUND AIMS: Third party virus-specific T cells (VST) has shown efficacy for opportunistic virus infection which do not have effective treatment or are drug-refractory. We describe our preparatory work in setting up a third-party VST bank for a multi-ethnic Asian population. METHODS: Discarded white cells from regular blood bank plateletpheresis donors with known locally prevalent HLA antigens were cultured in small scale to generate VST against Adenovirus, BK virus, Cytomegalovirus, Epstein-Barr virus, and Human Herpes Virus 6. Multi-virus specific T cells (multi-VST) were also generated against all 5 viruses in single cultures. A strategy of allelic typing for donors with good and broad-spectrum cytotoxicity together with consideration on HLA restriction for the virus epitope was used to select combinations of VST lines for a hypothetical third party VST bank. The breadth of coverage based on these selection criteria was validated using our database of 100 post haematopoietic stem cell transplant patients. RESULTS: We show that 50%, 42%, 56%, 56% and 42% of single VST cultures demonstrated specific cytotoxicity against AdV, BKV, CMV, EBV and HHV6 respectively. Twenty four of the 36 multi-VST lines showed activity against at least 2 of the 5 viruses studied. A carefully selected combination of just 6 VST lines can offer VST with at least 1 allelic match to 99% of potential recipients, while 92% can find 2 allelic matches and 79% can find 3 allelic matches. CONCLUSIONS: This preparatory work confirms that a cost-effective strategy recruiting a small number of pre-characterized donors can generate VST lines with broad coverage for a multi-ethnic Asian patient population, thereby laying the foundation for setting up of a third party VST bank for Asian patients.

Favorable outcomes of COVID-19 in vaccinated hematopoietic stem cell transplant recipients: A single-center experience.

INTRODUCTION: A high incidence of mortality and severe COVID-19 infection was reported in hematopoietic stem cell transplant (HSCT) recipients during the early phases of the COVID-19 pandemic; however, outcomes with subsequent severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) variants, such as the omicron variant, have yet to be reported. Additionally, rollout of COVID-19 vaccinations in subsequent pandemic waves may modify COVID-19 disease severity and mortality in this immunocompromised population. We describe COVID-19 outcomes among a highly vaccinated population of HSCT recipients at a single center during successive waves of community transmission arising from the SARS-CoV-2 delta and omicron variants. METHODS: We retrospectively reviewed medical records of all HSCT recipients at our institution who tested positive for SARS-CoV-2 from May 2021 to May 2022. Descriptive statistics were reported; the chi-square test was utilized to identify factors associated with 90-day all-cause mortality and severity of COVID-19 infection. RESULTS: Over the 1-year study period, 77 HSCT recipients at our center contracted COVID-19 (43 allogenic; 34 autologous). Twenty-six (33.8%) patients were infected with the SARS-CoV-2 delta variant, while 51 (66.2%) had the SARS-CoV-2 omicron variant. Thirty-nine (50.6%) patients required hospitalization. More than 80% had received prior COVID-19 vaccination (57.1% with two doses, 27.3% with three doses). The majority (90.9%) had mild disease; only one (1.3%) patient required mechanical ventilation. Active hematological disease at time of COVID-19 infection was associated with increased odds of mortality [odds ratio (OR) = 6.90, 95% confidence interval (CI) = 1.20-40]. The 90-day all-cause mortality was 7.8% (six patients). Infection with the omicron variant (vs. delta) was associated with less severe illness (OR = 0.05, 95% CI = 0.01-0.47) and decreased odds of mortality (OR = 0.08, 95% CI = 0.01-0.76). Being on immunosuppression (OR = 5.10, 95% CI = 1.10-23.60) and being unvaccinated at disease onset (OR = 14.76, 95% CI = 2.89-75.4) were associated with greater severity of COVID-19 infection. CONCLUSION: We observed favorable outcomes with COVID-19 infection in a cohort of vaccinated HSCT patients. The SARS-CoV-2 omicron variant was associated with both less severe illness and decreased odds of mortality. As COVID-19 moves toward endemicity, early access to treatment and encouraging vaccination uptake is crucial in mitigating the challenge of COVID-19 management among HSCT recipients. Surveillance and assessment of clinical outcomes with new SARS-CoV-2 variants also remains important in this immunocompromised population.

A novel simplified method of generating cytomegalovirus-specific cytokine-induced killer cells of high specificity and superior potency with GMP compliance.

We describe a method of rendering polyclonal cytokine-induced killer cells (CIK) specific against cytomegalovirus (CMV), focusing on GMP compliance. Peripheral blood mononuclear cells (PBMNC) are stimulated with pooled CMV peptides pp65 and IE-1 for 16-24 h and the reactive T cell subset which up-regulate CD137 is further co-stimulated with anti-CD137, followed by expansion in G-Rex flasks under standard CIK culture condition. This method generates a large number CMV-specific CIK with superior potency compared to published method currently in clinical trials. The cytotoxicity as measured by chromium release assay correlates with the upregulation of CD107a upon peptide re-challenge as measured by flow cytometry. CMV-CIK at maturity consist of mainly late effector memory CD8 T cells and have a skewed TCR repertoire with preferential expansion of a few families. Such CMV-CIK retain their function after freezing and thawing. CMV-CIK thus generated is ready for clinical trial against drug-resistant CMV disease.

Donor-type fresh frozen plasma is effective in preventing hemolytic reaction in major ABO incompatible allogeneic stem cell transplant.

BACKGROUND: Hemolysis at the time of graft infusion is one of the immediate complications in major ABO-incompatible allogeneic hematopoietic stem cell transplants (HSCTs). We conducted a retrospective analysis to evaluate the efficacy of donor-type fresh frozen plasma (FFP) in reducing isohemagglutinin titer and preventing hemolysis, as well as its effect on delayed red cell engraftment. MATERIALS AND METHODS: This is a single-center study on a series of 380 allogeneic HSCT between 2005 and 2015; of which 99 were either major (n = 74) or bidirectional (n = 25) ABO mismatched. Pre-transplant infusion of FFP, post-transplant complications and transfusion requirements were determined by retrospective review of individual medical records. Laboratory results were also reviewed for evidence of hemolysis and pure red cell aplasia (PRCA). RESULTS: Clinical manifestation of hemolysis attributable to ABO mismatch was present in one recipient of major ABO-incompatible peripheral blood stem cell (PBSC) with a titer of 64. Another recipient of major ABO-incompatible PBSC with a titer of 64 showed biochemical evidence of hemolysis. Both patients recovered with supportive treatment. Hemolysis did not occur in any patients with titer of 32 or less at the time of stem cell infusion. We were unable to demonstrate the influence of any variables on the incidence of PRCA. CONCLUSION: Our experience demonstrated that donor-type FFP is safe and effective in preventing acute hemolysis in major ABO-mismatched HSCT. We have also established the titer of 64 as the threshold that may cause hemolysis and therefore efforts should be made to reduce titer to below this level.

Long-term renal outcome after allogeneic hemopoietic stem cell transplant: A comprehensive analysis of risk factors in an Asian patient population.

Allogeneic hemopoietic stem cell transplantation (allo-HSCT) poses a significant challenge to renal function due to multiple drug- and complication-related renal toxicity. In this single-center series of 216 adult Asian patients with a long and complete follow-up, 41 developed chronic kidney disease (CKD) giving a cumulative incidence of 19.0% at 25 years (median follow-up duration 7.84 years, range 2.0-27.7 years), but only two of the 41 patients reached stage 4 CKD and another two required dialysis. In contrast, acute kidney injury occurred in most patients, where glomerular filtration rate (GFR) suffered a mean fall of 50 mL/min/1.73 m2 at 6 months post-transplant compared with baseline. Suppression of renal function may last beyond 6 months but is potentially reversible, although not to baseline level in most patients. Analysis of a comprehensive range of 18 risk factors showed that older age, lower GFR at transplant, unrelated donor, diagnosis of AML, presence of diabetes mellitus at transplant, and duration of foscarnet use were significantly associated with CKD development, with the first three remaining as independent risks for CKD in multivariate analysis. Long-term survival is not affected by renal function, being 78.6% as compared to 85.5% for patients with low vs normal GFR at 2 years, respectively.

Respiratory virus infection after allogeneic hematopoietic stem cell transplant in a tropical center: Predictive value of the immunodeficiency scoring index.

BACKGROUND: Respiratory virus infection (RVI) is a prevalent infection in patients after allogeneic hematopoietic stem cell transplant (allo-HSCT) and can result in significant morbidity and mortality. Ability to assess the potential severity of RVI is important in the management of such patients. METHODS: We reviewed the cases of RVI in allo-HSCT recipients and explored the predictive value of the immunodeficiency scoring index (ISI) established for respiratory syncytial virus (RSV) and its applicability for RVI caused by other respiratory viruses. RESULTS: RVI occurred year-round in our tropical transplant center, with peaks in the middle and end of the year. Ninety-five of the 195 recipients developed a total of 191 episodes of RVI, giving a cumulative incidence of 28% by 6 months and 52% by 24 months for the first episode of RVI. RSV, influenza, rhinovirus, and parainfluenza were the most common viruses. Pneumonia occurred in 63.64%, 42.31%, and 32.42% of adenovirus, influenza, and RSV RVI episodes, respectively, but was also non-negligible in the more benign viruses, such as coronavirus (31.58%) and rhinovirus (23.68%). Nineteen of the 63 episodes of viral pneumonia required mechanical ventilation and 14 deaths occurred within 6 weeks of the RVI. Receiver operating characteristic analysis showed that an ISI of ≥8 predicted pneumonia with a positive predictive value of >80% for RVI caused by RSV, influenza, adenovirus, and parainfluenza, while it was not predictive for coronavirus and rhinovirus. CONCLUSIONS: The ISI is a useful aid for decision-making during clinic consultation for patients presenting with symptoms suggestive of an RVI.

KIR-HLA profiling shows presence of higher frequencies of strong inhibitory KIR-ligands among prognostically poor risk AML patients.

The expression and interaction between killer cell immunoglobulin-like receptors (KIRs) and HLA are known to be associated with pathogenesis of diseases, including hematological malignancies. Presence of B haplotype KIR in donors is associated with a lower relapse risk for acute myeloid leukemia (AML) after hematopoietic stem cell transplants (HSCT). However, the association of KIR and HLA repertoire with disease development and other clinical features is not well studied for AML. In this study, 206 Chinese patients with AML were analyzed for their FAB subtypes, risk groups, and chemo-responsiveness to assess possible association with their KIR and HLA profile. The results revealed that a B-content score of 2 was significantly more prevalent in AML patients when compared to normal controls. Notably, there is also a differential frequency in the distribution of B haplotype KIR across distinct FAB subtypes, where the M3 subtype had significantly lower frequencies of B haplotype KIR compared to the M5 subtype (p < 0.05). In addition, the stronger inhibitory KIR ligands HLA-C2 and HLA-Bw4-80I were present in significantly higher frequencies in the prognostically "poor" risk group compared to those with "favourable" risk (p < 0.01). Taken together, these associations with clinical features of AML suggest a role of the KIR-HLA repertoire in the development and biological behavior of AML.

Immune checkpoint inhibitors enhance cytotoxicity of cytokine-induced killer cells against human myeloid leukaemic blasts.

We studied whether blockade of inhibitory receptors on cytokine-induced killer (CIK) cells by immune checkpoint inhibitors could increase its anti-tumour potency against haematological malignancies. CIK cultures were generated from seven normal donors and nine patients with acute myeloid leukaemia (AML), acute lymphoblastic leukaemia (ALL) or multiple myeloma (MM). The inhibitory receptors B and T lymphocyte attenuator, CD200 receptor, lymphocyte activation gene-3 (LAG-3) and T cell immunoglobulin and mucin-domain-containing-3 (TIM-3) were present at variable percentages in most CIK cultures, while cytotoxic T lymphocyte-associated protein 4 (CTLA-4), programmed death-1 (PD-1) and killer cell immunoglobulin-like receptors (KIR2DL1/2/3) were expressed at low level in most cultures. Without blockade, myeloid leukaemia cells were susceptible to autologous and allogeneic CIK-mediated cytotoxicity. Blockade of KIR, LAG-3, PD-1 and TIM-3 but not CTLA-4 resulted in remarkable increase in killing against these targets, even in those with poor baseline cytotoxicity. ALL and MM targets were resistant to CIK-mediated cytotoxicity, and blockade of receptors did not increase cytotoxicity to a meaningful extent. Combination of inhibitors against two receptors did not further increase cytotoxicity. Interestingly, potentiation of CIK killing by blocking antibodies was not predicted by expression of receptors on CIK and their respective ligands on the targets. Compared to un-activated T and NK cells, blockade potentiated the cytotoxicity of CIK cells to a greater degree and at a lower E:T ratio, but without significant increase in cytotoxicity against normal white cell. Our findings provide the basis for clinical trial combining autologous CIK cells with checkpoint inhibitors for patients with AML.

Natural Killer Cells for Therapy of Leukemia.

Clinical application of natural killer (NK) cells against leukemia is an area of intense investigation. In human leukocyte antigen-mismatched allogeneic hematopoietic stem cell transplantations (HSCT), alloreactive NK cells exert powerful anti-leukemic activity in preventing relapse in the absence of graft-versus-host disease, particularly in acute myeloid leukemia patients. Adoptive transfer of donor NK cells post-HSCT or in non-transplant scenarios may be superior to the currently widely used unmanipulated donor lymphocyte infusion. This concept could be further improved through transfusion of activated NK cells. Significant progress has been made in good manufacturing practice (GMP)-compliant large-scale production of stimulated effectors. However, inherent limitations remain. These include differing yields and compositions of the end-product due to donor variability and inefficient means for cryopreservation. Moreover, the impact of the various novel activation strategies on NK cell biology and in vivo behavior are barely understood. In contrast, reproduction of the third-party NK-92 drug from a cryostored GMP-compliant master cell bank is straightforward and efficient. Safety for the application of this highly cytotoxic cell line was demonstrated in first clinical trials. This novel 'off-the-shelf' product could become a treatment option for a broad patient population. For specific tumor targeting chimeric-antigen-receptor-engineered NK-92 cells have been designed.

WPSS is a strong prognostic indicator for clinical outcome of allogeneic transplant for myelodysplastic syndrome in Southeast Asian patients.

To better understand the predictive factors and improve clinical outcome of allogeneic transplant for patients with myelodysplastic syndrome (MDS), we retrospectively analyzed the post-transplant outcome of 60 Southeast Asian patients with MDS. Multivariate analysis showed that WHO classification-based Prognostic Scoring System (WPSS) significantly affect overall survival (OS), progression-free survival (PFS), cumulative incidence of relapse (CIR), and cumulative incidence of non-relapse mortality (CINRM). Stratified by WPSS into very low/low, intermediate, high, and very high-risk categories, 3-year OS was 100, 61, 37, and 18% (p = 0.02); PFS was 100, 55, 32, and 18% (p = 0.014); CIR was 12, 24, 38, and 59% (p = 0.024); CINRM was 0, 6, 12, and 26% (p = 0.037), respectively. WHO classification, Revised International Prognostic Scoring System (IPSS-R), IPSS-R-defined cytogenetic risk groups, donor gender, and acute and chronic graft vs host disease (GVHD) also influenced different aspects of transplant outcome. We found that WPSS is a powerful predictor of post-transplant outcome. WPSS provides an important model not only for prognostication but also for exploration of further post-transplant measures such as immunological maneuvers or novel therapy to improve the poor outcome of high-risk patients.

The road to memory: an early rest for the long journey.

Central memory T lymphocytes were reported to develop after acute but not chronic infection, which prompted this feasibility study on generating long-term CD8 T cells ex vivo, by applying a culture condition that simulates an acute infection. During 35 d of culture, naive T cells (CD45RA(+), CD127(+), CCR7(+), CD62L(+), CXCR3(+)) first developed into effector T cells (CD45RA(+/-), CD127(+/-), CCR7(+/-), CD62L(+), CXCR3(+)), followed by three intermediate stages: intermediate T cells 1 (CD45RO(+), CD127(+/-), CCR7(+), CD62L(+), CXCR3(+)), intermediate T cells 2 (CD45RO(+), CD127(-), CCR7(-), CD62L(+), CXCR3(+)), and intermediate T cells 3 (CD45RO(+/-), CD127(+), CCR7(+), CD62L(-), CXCR3(+)) before reverting to stable CD45RA(+) central memory T cells (CD45RA(+), CD127(+), CCR7(+), CD62L(+), CXCR3(+)). If both anti-CD3 and the inflammatory milieu persisted beyond day 10, intermediate T cells 2 gradually developed into effector memory T cells (CD45RO(+), CD127(-), CCR7(-), CD62L(-), CXCR3(+)). Furthermore, intermediate T cells 2 or effector memory T cells, when cultured in persistent inflammatory cytokines devoid of anti-CD3, were converted to central memory T cells (CD45RO(+), CCR7(+), CD62L(+)). Overall, these results support ex vivo memory-like T lymphocyte production and favor a developmental pathway including both divergent and linear relationships.

CD137 ligand signalling induces differentiation of primary acute myeloid leukaemia cells.

CD137 ligand (CD137L), a member of the tumour necrosis factor family, is expressed as a cell surface molecule. Engagement of CD137L on haematopoietic progenitor cells induces monocytic differentiation, and in peripheral monocytes CD137L signalling promotes differentiation to mature dendritic cells. We hypothesized that CD137L signalling would also induce differentiation in transformed myeloid cells. Here we show that recombinant CD137 protein, which crosslinks CD137L and initiates reverse CD137L signalling in myeloid cells, induces morphological changes (adherence, spreading), loss of progenitor markers (CD117), expression of maturation markers (CD11b, CD13) and secretion of cytokines that are indicative of myeloid differentiation. Under the influence of CD137L signalling, acute myeloid leukaemia (AML) cells acquired expression of co-stimulatory molecules (CD80, CD86, CD40), the dendritic cell marker CD83 and dendritic cell activities, enabling them to stimulate T cells. CD137L signalling induced differentiation in 71% (15 of 21) of AML samples, irrespective of French-American-British classification and CD137L expression level. However, the type of response varied with the AML subtype and patient sample. In summary, this study demonstrated that CD137L signalling induced differentiation in malignant cells of AML patients, and suggests that it may be worthwhile to investigate treatment with recombinant CD137 protein as a potential novel therapeutic approach for AML.

Conjunctival T Cell Profile in Allogeneic Hematopoietic Stem Cell Transplant Patients after Instilling Topical Cyclosporine-A 0.1% Cationic Emulsion.

INTRODUCTION: To profile conjunctival T cell populations in allogeneic hematopoietic stem cell transplant (HSCT) patients after instillation of daily topical cyclosporine-A (CsA) 0.1% cationic emulsion (Ikervis), and to evaluate patients' tolerance to these eye drops. METHODS: Nineteen participants were prescribed Ikervis prophylaxis once daily to both eyes from 3-5 weeks pre-HSCT to 12 months post-HSCT. The outcome measure was conjunctival T cell proportions from flow cytometry after impression cytology. Covariates included visual acuity, intraocular pressure, slit lamp and fundal examination, dry eye (SPEED) and quality of life questionnaires, non-invasive keratograph tear break-up time (NIKBUT), conjunctival redness, meibography, lipid thickness, Schirmer test, tear cytokines, fluorescein staining, tear osmolarity, and meibomian gland expressibility. RESULTS: The conjunctival T cell analysis showed either stable or decreased proportions of conjunctival CD4 T cells at the last visit from baseline in compliant patients. CD4 proportions were increased in non-compliant patients and in the single patient who developed ocular graft-versus-host disease (GVHD). All patients were tolerant to Ikervis but 6/19 were not compliant. In the majority of patients, vision did not affect activities of daily living. Pre- and post-HSCT up to the last study visit, there was no statistically significant change in clinical covariates. Only one participant developed ocular GVHD at 9 months post-HSCT. CONCLUSION: Superficial conjunctival T cell profile reflects compliance to daily topical Ikervis eye drops and clinical ocular surface parameters in allogenic HSCT patients. Tolerance is comparable to other formulations of topical CsA in the first 12 months. GOV IDENTIFIER: NCT04636918. URL: https://clinicaltrials.gov/ct2/show/NCT04636918?cond=ocular+Graft+Versus+Host+Disease&cntry=SG&draw=2&rank=2 .

AL amyloidosis: Singapore Myeloma Study Group consensus guidelines on diagnosis, treatment and management.

AL amyloidosis is the most common form of systemic amyloidosis. However, the non-specific nature of presenting symptoms requires the need for a heightened clinical suspicion to detect unexplained manifestations in the appropriate clinical setting. Early detection and treatment are crucial as the degree of cardiac involvement emerges as a primary prognostic predictor of survival in a patient with AL amyloidosis. Following the diagnosis of AL amyloidosis with appropriate tissue biopsies, prompt treatment with a bortezomib, cyclophosphamide and dexamethasone-based first-line induction with or without daratumumab should be initiated. The goal of treatment is to achieve the best haematologic response possible, ideally with involved free light chain <20 mg/L, as it offers the best chance of organ function improvement. Treatment should be changed if patients do not achieve a partial response within 2 cycles of treatment or very good partial response after 4 cycles or after autologous stem cell transplant, as achievement of profound and prolonged clonal responses translates to better organ response and long-term outcomes. Early involvement of multidisciplinary subspecialists such as renal physicians, cardiologists, neurologists, and gastroenterologists for optimal maintenance and support of involved organs is recommended for optimal management of patients with AL amyloidosis.

Effects of Leea indica leaf extracts and its phytoconstituents on natural killer cell-mediated cytotoxicity in human ovarian cancer.

BACKGROUND: The rich biodiversity of medicinal plants and their importance as sources of novel therapeutics and lead compounds warrant further research. Despite advances in debulking surgery and chemotherapy, the risks of recurrence of ovarian cancer and resistance to therapy are significant and the clinical outcomes of ovarian cancer remain poor or even incurable. OBJECTIVE: This study aims to investigate the effects of leaf extracts from a medicinal plant Leea indica and its selected phytoconstituents on human ovarian cancer cells and in combination with oxaliplatin and natural killer (NK) cells. METHODS: Fresh, healthy leaves of L. indica were harvested and extracted in 70% methanol by maceration. The crude extract was partitioned with n-hexane, dichloromethane and ethyl acetate. Selected extracts and compounds were analyzed for their effects on cell viability of human ovarian cancer cells, NK cell cytotoxicity, and stress ligands expression for NK cell receptors. They were also evaluated for their effects on TNF-α and IL-1ß production by enzyme-linked immunosorbent assay in lipopolysaccharide-stimulated human U937 macrophages. RESULTS: Leaf extracts of L. indica increased the susceptibility of human ovarian tumor cells to NK cell-mediated cytotoxicity. Treatment of cancer cells with methyl gallate but not gallic acid upregulated the expression of stress ligands. Tumor cells pretreated with combination of methyl gallate and low concentration of oxaliplatin displayed increased levels of stress ligands expression and concomitantly enhanced susceptibility to NK cell-mediated cytolysis. Further, NK cells completely abrogated the growth of methyl gallate-pretreated ovarian cancer cells. The leaf extracts suppressed TNF-α and IL-1ß production in human U937 macrophages. Methyl gallate was more potent than gallic acid in down-regulating these cytokine levels. CONCLUSIONS: We demonstrated for the first time that leaf extracts of L. indica and its phytoconstituent methyl gallate enhanced the susceptibility of ovarian tumor cells to NK cell cytolysis. These results suggest that the combined effect of methyl gallate, oxaliplatin and NK cells in ovarian cancer cells warrants further investigation, for example for refractory ovarian cancer. Our work is a step towards better scientific understanding of the traditional anticancer use of L. indica.

A phase I/II clinical trial of autologous cytokine-induced killer cells as adjuvant immunotherapy for acute and chronic myeloid leukemia in clinical remission.

BACKGROUND AIMS: Cytokine-induced killer (CIK) cells have shown remarkable cytotoxicity against various tumors in vitro and in animal studies. We report on the clinical outcome of autologous CIK cells for patients with acute (AML) and chronic (CML) myeloid leukemia in remission. METHODS: Eleven of the 13 recruited AML patients undergoing autologous peripheral blood stem cell transplant (autoPBSCT) were given autologous CIK cell infusion upon engraftment post-transplant and followed-up for disease relapse. Eleven CML patients on Imatinib with residual disease detectable by polymerase chain reaction (PCR) were given infusion and monitored by quantitation of the bcr-abl transcript. RESULTS: Despite the presence of interferon (IFN)-γ-secreting T cells against various AML- and CML-associated peptides at sporadic time-points and demonstration of in vitro cytotoxicity of CIK cells against autologous and allogeneic AML targets, there was no survival benefit in AML patients post-autoPBSCT given CIK cells compared with historical controls. For CML patients, all continued to have a detectable bcr-abl transcript fluctuating within a range comparable to their pre-treatment baseline, although two had a transient but non-sustainable disappearance of bcr-abl transcript. There were no adverse reactions except for fever within the first day of infusion. CONCLUSIONS: Our small series, while confirming safety, failed to demonstrate a clinical benefit of autologous CIK cells given in its current form for AML and CML. Further manipulation of CIK cells to improve anti-leukemic potency and specificity, together with the preparation of patients to create a more conducive milieu for in vivo expansion and persistence of infused CIK cells, should be explored.

Comparing peripheral blood stem cell collection using the COBE Spectra, Haemonetics MCS+, and Baxter Amicus.

Peripheral blood stem cells (PBSC) have become the most common source of hematopoietic cells for allogeneic or autologous blood and marrow transplantation (BMT). We performed an evaluation of PBSC collections using three different apheresis systems in two major transplantation centers in Singapore. Patients undergoing autologous BMT and donors collecting for allogeneic BMT were harvested using the COBE Spectra, Haemonetics MCS+, or Baxter Amicus. There were 99 Spectra collections (61 were autologous), 81 MCS+ collections (35 were autologous) and 38 Amicus collections (33 were autologous). Our data shows that the Amicus not only processed larger peripheral blood volumes but also yielded larger PBSC volume (P-value<0.05). In terms of PBSC products, the Spectra produced more WBC, WBC/liter blood processed, and WBC/kg (P-value<0.05). The Spectra and MCS+ produced comparable amount of CD34+ cells. Amicus collected 50% less platelets compared to Spectra and MCS+. The total CD34+ cells in the PBSC products was linearly correlated to the circulating CD34+ cells using Spectra, MCS+, and Amicus. Our results suggest that, compared to MCS+ and Amicus, collecting PBSC using the COBE Spectra can produce more WBC with a similar number of CD34+ cells. With a linear correlation of circulating CD34+ cells to the total CD34+ cells in the products, the availability of an automated procedure, no rotating seal, and a small extracorporeal volume, the Spectra appears to be the preferred machine for PBSC collection.