Discovery of quinazoline HPK1 inhibitors with high cellular potency.

Hematopoietic progenitor kinase 1 (HPK1) is regarded as a highly validated target in pre-clinical immune oncology. HPK1 has been described as regulating multiple critical signaling pathway in both adaptive and innate cells. In support of this role, HPK1 KO T cells show enhanced sensitivity to TCR activation and HPK1 KO mice display enhanced anti-tumor activity. Taken together, inhibition of HPK1 has the potential to induce enhanced anti-tumor immune response. Herein, we described the discovery of highly potent HPK1 inhibitors starting form a weak HTS hit. Using a structure-based drug design, HPK1 inhibitors exhibiting excellent cellular single-digit nanomolar potency in both proximal (pSLP76) and distal (IL-2) biomarkers along with sustained elevation of IL-2 cytokine secretion were discovered.

Towards estimating the carbon footprint of external beam radiotherapy.

PURPOSE: The National Health Service (NHS) in the United Kingdom (UK) is aiming to be carbon net zero by 2040 to help limit the dangerous effects of climate change. Radiotherapy contributes to this with potential sources quantified here. METHOD: Activity data for 42 patients from within the breast IMRT and prostate VMAT pathways were collected. Data for 20 prostate patients was also collected from 3 other centres to enable cross centre comparison. A process-based, bottom-up approach was used to calculate the carbon footprint. Additionally, patients were split into pre-COVID and COVID groups to assess the impact of protocol changes due to the pandemic. RESULTS: The calculated carbon footprint for prostate and breast pre-COVID were 148 kgCO2e and 101 kgCO2e respectively, and 226 kgCO2e and 75 kgCO2e respectively during COVID. The energy usage by the linac during treatment for a total course of radiotherapy for prostate treatments was 2-3 kWh and about 1 kWh for breast treatments. Patient travel made up the largest proportion (70-80%) of the calculated carbon footprint, with linac idle power second with âˆ¼ 10% and PPE and SF6 leakage were both between 2 and 4%. CONCLUSION: These initial findings highlight that the biggest contributor to the external beam radiotherapy carbon footprint was patient travel, which may motivate increased used of hypofractionation. Many assumptions and boundaries have been set on the data gathered, which limit the wider application of these results. However, they provide a useful foundation for future more comprehensive life cycle assessments.

Care Levels for Fetal Therapy Centers.

Fetal therapies undertaken to improve fetal outcome or to optimize transition to neonate life often entail some level of maternal, fetal, or neonatal risk. A fetal therapy center needs access to resources to carry out such therapies and to manage maternal, fetal, and neonatal complications that might arise, either related to the therapy per se or as part of the underlying fetal or maternal condition. Accordingly, a fetal therapy center requires a dedicated operational infrastructure and necessary resources to allow for appropriate oversight and monitoring of clinical performance and to facilitate multidisciplinary collaboration between the relevant specialties. Three care levels for fetal therapy centers are proposed to match the anticipated care complexity, with appropriate resources to achieve an optimal outcome at an institutional and regional level. A level I fetal therapy center should be capable of offering fetal interventions that may be associated with obstetric risks of preterm birth or membrane rupture but that would be very unlikely to require maternal medical subspecialty or intensive care, with neonatal risks not exceeding those of moderate prematurity. A level II center should have the incremental capacity to provide maternal intensive care and to manage extreme neonatal prematurity. A level III therapy center should offer the full range of fetal interventions (including open fetal surgery) and be able manage any of the associated maternal complications and comorbidities, as well as have access to neonatal and pediatric surgical intervention including indicated surgery for neonates with congenital anomalies.

Postnatal Corticosteroids to Prevent or Treat Chronic Lung Disease Following Preterm Birth.

The American Academy of Pediatrics continues to provide guidance on the use of postnatal corticosteroids to manage or prevent chronic lung disease following preterm birth (formerly referred to as bronchopulmonary dysplasia). Since the last revision of such guidance in 2010, several prospective randomized trials have been published. This revision provides a review of those studies as well as updated recommendations, which include the use of systemic low-dose corticosteroid in preterm neonates with or at high risk for chronic lung disease. High-dose dexamethasone (≥0.5 mg/kg per day) is not recommended. New evidence suggests that inhaled corticosteroids may confer benefit if provided with surfactant as a vehicle, but safety data are lacking. Evidence remains insufficient to make any recommendations regarding routine use of postnatal corticosteroids in preterm infants. Neonatologists and other hospital care providers must continue to use their clinical judgment in individual patients, balancing the potential adverse effects of corticosteroid treatment with those of chronic lung disease. The decision to use postnatal corticosteroids for this purpose should be made together with the infant's parents, and the care providers should document their discussions with parents in the patient's medical record.

Advancing peptide siRNA-carrier designs through L/D-amino acid stereochemical modifications to enhance gene silencing.

The 599 peptide has been previously shown to effectively deliver small interfering RNAs (siRNAs) to cancer cells, inducing targeted-oncogene silencing, with a consequent inhibition of tumor growth. Although effective, this study was undertaken to advance the 599 peptide siRNA-carrier design through L/D-amino acid stereochemical modifications. Consequently, 599 was modified to generate eight different peptide variants, incorporating either different stereochemical patterns of L/D-amino acids or a specific D-amino acid substitution. Upon analysis of the variants, it was observed that these modifications could, in some instances, increase/decrease the binding, nuclease/serum stability, and complex release of siRNAs, as well as influence the gene-silencing efficiencies of the complex. These modifications were also found to affect cellular uptake and intracellular localization patterns of siRNA cargo, with one particular variant capable of mediating binding of siRNAs to specific cellular projections, identified as filopodia. Interestingly, this variant also exhibited the most enhanced gene silencing in comparison to the parent 599 peptide, thus suggesting a possible connection between filopodia binding and enhanced gene silencing. Together, these data demonstrate the utility of peptide stereochemistry, as well as the importance of a key D-amino acid modification, in advancing the 599 carrier design for the enhancement of gene silencing in cancer cells.

Optimizing Resources in Children's Surgical Care: An Update on the American College of Surgeons' Verification Program.

Surgical procedures are performed in the United States in a wide variety of clinical settings and with variation in clinical outcomes. In May 2012, the Task Force for Children's Surgical Care, an ad hoc multidisciplinary group comprising physicians representing specialties relevant to pediatric perioperative care, was convened to generate recommendations to optimize the delivery of children's surgical care. This group generated a white paper detailing the consensus opinions of the involved experts. Following these initial recommendations, the American College of Surgeons (ACS), Children's Hospital Association, and Task Force for Children's Surgical Care, with input from all related perioperative specialties, developed and published specific and detailed resource and quality standards designed to improve children's surgical care (https://www.facs.org/quality-programs/childrens-surgery/childrens-surgery-verification). In 2015, with the endorsement of the American Academy of Pediatrics (https://pediatrics.aappublications.org/content/135/6/e1538), the ACS established a pilot verification program. In January 2017, after completion of the pilot program, the ACS Children's Surgery Verification Quality Improvement Program was officially launched. Verified sites are listed on the program Web site at https://www.facs.org/quality-programs/childrens-surgery/childrens-surgery-verification/centers, and more than 150 are interested in verification. This report provides an update on the ACS Children's Surgery Verification Quality Improvement Program as it continues to evolve.

Peptide carriers to the rescue: overcoming the barriers to siRNA delivery for cancer treatment.

Cancer is a significant health concern worldwide and its clinical treatment presents many challenges. Consequently, much research effort has focused on the development of new anticancer drugs to combat this disease. One area of exploration, in particular, has been in the therapeutic application of RNA interference (RNAi). Although RNAi appears to be an attractive therapeutic tool for the treatment of cancer, one of the primary obstacles towards its pervasive use in the clinic has been cell/tissue type-specific cytosolic delivery of therapeutic small interfering RNA (siRNA) molecules. Consequently, varied drug delivery platforms have been developed and widely explored for siRNA delivery. Among these candidate drug delivery systems, peptides have shown great promise as siRNA carriers due to their varied physiochemical properties and functions, simple formulations, and flexibility in design. In this review, we will focus on distinguishing between the different classes of peptide carriers based on their functions, as well as summarize and discuss the various design strategies and advancements that have been made in circumventing the barriers to siRNA delivery for cancer treatment. Resolution of these challenges by peptide carriers will accelerate the translation of RNAi-based therapies to the clinic.

Assessment of Patient and Surgical Variables Including Residency Training Level on Adverse Events After Ureteroscopy for Ureteral Stones: A Multivariate Analysis.

PURPOSE: With advances in technology, ureteroscopy (URS) is increasingly utilized for the management of urolithiasis. Previous studies have attempted to characterize the post-operative complication and readmission rates relative to the technical difficulty of the procedure. There is limited data exploring the resident level of training and its effect on adverse outcomes in these cases. We review our experience with URS to create a model to predict factors, including resident experience, that affect rates of post-operative complications. MATERIALS AND METHODS: We reviewed ureteroscopies performed at our academic facility from January 2009 to December 2013. Ureteral-only stones were examined for demographics, stone characteristics, operative techniques, and resident training level. Post-operative adverse events requiring urology consultation, clinic or emergency department visits, hospital admission, prolonged post-operative hospitalization, or unplanned repeat surgery within 30 days of the procedure were identified and analyzed. RESULTS: Four hundred seventeen cases of URS for ureteral-only stones were included for study. We identified 53 (12.7%) involving an unexpected post-operative course. Several logistic regression models were created to make a predictive model of adverse events. One model found only lack of stone clearance to be significant for increasing the likelihood of an adverse event. A second model determined that no residency year showed higher odds of adverse outcomes. CONCLUSIONS: URS has increased in prevalence in recent years, but overall complication rates are low. Resident level of experience does not appear to impact adverse event rate. Stone clearance during initial surgery appears to be the most important in avoiding adverse events. Further expansion of the database over time will improve our ability to predict adverse outcomes in this common procedure.

Is the robotic approach feasible for repair of iatrogenic injuries of the lower ureter?

OBJECTIVES: To analyze the robotic approach as treatment of iatrogenic ureteral injuries. METHODS: Medical records were reviewed for patients undergoing robotic-assisted laparoscopic ureteral reimplantation at the University of Missouri from 2009 to 2014. Patient charts were analyzed for demographics, prior abdominal surgeries, circumstances of injury, outcomes, and other relevant information. RESULTS: Nine patients met inclusion criteria. The average age was 44.6. Patients had an average of 4.3 abdominal surgeries. Injury occurred during hysterectomy (open, laparoscopic, or vaginal) in eight patients (88.9 %), five cases were laparoscopic, two utilized robotic assistance, and one injury occurred during uterosacral vault suspension. All cases were related to gynecological procedures. On average, ureteral injury was detected 17.2 days after the initial surgery and repaired 62.3 days after initial operation. The average surgical repair time was 295.9 min (range 168-498) with an average blood loss of 77.2 mL (range 20-150). Four patients required a psoas hitch, with one receiving both a psoas hitch and a Boari flap. Postoperatively, patients had an average hospital stay of 2.7 days. One patient had ileus for greater than 3 days, and another was readmitted within 30 days for pain control and antiemetics following stent removal. One patient underwent open reimplantation 3 years after original surgery for development of ureteral stricture. At follow-up, all patients had returned to baseline renal function. CONCLUSIONS: Robotic approach is feasible and a safe option for distal iatrogenic ureteral injuries occurring during gynecological procedures. Prior abdominal surgery or delayed repair does not preclude a robotic approach.

Noninvasive Respiratory Support.

Mechanical ventilation is associated with increased survival of preterm infants but is also associated with an increased incidence of chronic lung disease (bronchopulmonary dysplasia) in survivors. Nasal continuous positive airway pressure (nCPAP) is a form of noninvasive ventilation that reduces the need for mechanical ventilation and decreases the combined outcome of death or bronchopulmonary dysplasia. Other modes of noninvasive ventilation, including nasal intermittent positive pressure ventilation, biphasic positive airway pressure, and high-flow nasal cannula, have recently been introduced into the NICU setting as potential alternatives to mechanical ventilation or nCPAP. Randomized controlled trials suggest that these newer modalities may be effective alternatives to nCPAP and may offer some advantages over nCPAP, but efficacy and safety data are limited.

Position statement on fetal myelomeningocele repair.

Following the promising multicenter randomized trial results of in utero fetal myelomeningocele repair; we anticipate that an increasing number of tertiary care centers may want to offer this therapy. It is essential to establish minimum criteria for centers providing open fetal myelomeningocele repair to ensure optimal maternal and fetal/pediatric outcomes, as well as patient safety both short- and long-term; and to advance our knowledge of the role and benefit of fetal surgery in the management of fetal myelomeningocele. The fetal myelomeningocele Maternal-Fetal Management Task Force was initially convened by the Eunice Kennedy Shriver National Institute of Child Health and Human Development to discuss the implementation of maternal fetal surgery for myelomeningocele. The decision was made to develop the optimal practice criteria presented in this document for the purpose of medical and surgical leadership. These criteria are not intended to be used for legal or regulatory purposes.

Safety and immunogenicity of a plant-produced recombinant monomer hemagglutinin-based influenza vaccine derived from influenza A (H1N1)pdm09 virus: a Phase 1 dose-escalation study in healthy adults.

BACKGROUND: Novel influenza viruses continue to pose a potential pandemic threat worldwide. In recent years, plants have been used to produce recombinant proteins, including subunit vaccines. A subunit influenza vaccine, HAC1, based on recombinant hemagglutinin from the 2009 pandemic A/California/04/2009 (H1N1) strain of influenza virus, has been manufactured using a plant virus-based transient expression technology in Nicotiana benthamiana plants and demonstrated to be immunogenic and safe in pre-clinical studies (Shoji et al., 2011). METHODS: A first-in-human, Phase 1, single-center, randomized, placebo-controlled, single-blind, dose escalation study was conducted to investigate safety, reactogenicity and immunogenicity of an HAC1 formulation at three escalating dose levels (15 µg, 45 µg and 90 µg) with and without Alhydrogel(®), in healthy adults 18-50 years of age (inclusive). Eighty participants were randomized into six study vaccine groups, a saline placebo group and an approved monovalent H1N1 vaccine group. Recipients received two doses of vaccine or placebo (except for the monovalent H1N1 vaccine cohort, which received a single dose of vaccine, later followed by a dose of placebo). RESULTS: The experimental vaccine was safe and well tolerated, and comparable to placebo and the approved monovalent H1N1 vaccine. Pain and tenderness at the injection site were the only local solicited reactions reported following vaccinations. Nearly all adverse events were mild to moderate in severity. The HAC1 vaccine was also immunogenic, with the highest seroconversion rates, based on serum hemagglutination-inhibition and virus microneutralization antibody titers, in the 90 µg non-adjuvanted HAC1 vaccine group after the second vaccine dose (78% and 100%, respectively). CONCLUSIONS: This is the first study demonstrating the safety and immunogenicity of a plant-produced subunit H1N1 influenza vaccine in healthy adults. The results support further clinical investigation of the HAC1 vaccine as well as demonstrate the feasibility of the plant-based technology for vaccine antigen production.

DNA prime/Adenovirus boost malaria vaccine encoding P. falciparum CSP and AMA1 induces sterile protection associated with cell-mediated immunity.

BACKGROUND: Gene-based vaccination using prime/boost regimens protects animals and humans against malaria, inducing cell-mediated responses that in animal models target liver stage malaria parasites. We tested a DNA prime/adenovirus boost malaria vaccine in a Phase 1 clinical trial with controlled human malaria infection. METHODOLOGY/PRINCIPAL FINDINGS: The vaccine regimen was three monthly doses of two DNA plasmids (DNA) followed four months later by a single boost with two non-replicating human serotype 5 adenovirus vectors (Ad). The constructs encoded genes expressing P. falciparum circumsporozoite protein (CSP) and apical membrane antigen-1 (AMA1). The regimen was safe and well-tolerated, with mostly mild adverse events that occurred at the site of injection. Only one AE (diarrhea), possibly related to immunization, was severe (Grade 3), preventing daily activities. Four weeks after the Ad boost, 15 study subjects were challenged with P. falciparum sporozoites by mosquito bite, and four (27%) were sterilely protected. Antibody responses by ELISA rose after Ad boost but were low (CSP geometric mean titer 210, range 44-817; AMA1 geometric mean micrograms/milliliter 11.9, range 1.5-102) and were not associated with protection. Ex vivo IFN-γ ELISpot responses after Ad boost were modest (CSP geometric mean spot forming cells/million peripheral blood mononuclear cells 86, range 13-408; AMA1 348, range 88-1270) and were highest in three protected subjects. ELISpot responses to AMA1 were significantly associated with protection (p = 0.019). Flow cytometry identified predominant IFN-γ mono-secreting CD8+ T cell responses in three protected subjects. No subjects with high pre-existing anti-Ad5 neutralizing antibodies were protected but the association was not statistically significant. SIGNIFICANCE: The DNA/Ad regimen provided the highest sterile immunity achieved against malaria following immunization with a gene-based subunit vaccine (27%). Protection was associated with cell-mediated immunity to AMA1, with CSP probably contributing. Substituting a low seroprevalence vector for Ad5 and supplementing CSP/AMA1 with additional antigens may improve protection. TRIAL REGISTRATION: ClinicalTrials.govNCT00870987.

International survey of transfusion practices for extremely premature infants.

Our objective was to survey neonatologists regarding international practice of red cell transfusion thresholds for premature infants with <1000-g birth weight and/or <28-week gestation. An invitation to fill out an 11-question web-based survey was distributed to neonatologists through their professional societies in 22 countries. Physicians were asked about which specific factors, in addition to hemoglobin levels, influenced their decisions about transfusing premature infants. These factors included gestational age, postnatal age, oxygen need, respiratory support, reticulocyte count, and inotropic support. Physicians were presented with 5 scenarios and asked to identify hemoglobin cutoff values for transfusing infants with <1000-g birth weight and/or <28-week gestation. One thousand eighteen neonatologists responded: the majority were from the United States (67.5%), followed by Germany (10.7%), Japan (8.0%), the United Kingdom (4.9%), Spain (3.9%), Italy (2.6%), Colombia (0.6%), Argentina (0.4%), Canada (0.4%), Belgium (0.1%), and the Netherlands (0.1%). Half of the respondents (51.1%) reported having a written policy with specific red cell transfusion guidelines in their unit. Factors considered "very important" regarding the need to administer blood transfusions included degree of oxygen requirement (44.7%) and need for respiratory support (44.1%). Erythropoietin was routinely used to treat anemia by 26.0% of respondents. Delayed cord clamping or cord milking was practiced by 29.1% of respondents. The main finding was of a wide variation in the hemoglobin values used to transfuse infants, regardless of postnatal age. Step-wise increments in the median hemoglobin cutoffs directly paralleled an increase in the need for levels of respiratory support. In the first week of life, there was a wider range in the distribution of hemoglobin transfusion thresholds for infants requiring no respiratory support and full mechanical ventilation compared with the thresholds used in the second, third, and fourth weeks of life. An international survey using hypothetical scenarios shows that red blood cell transfusion practices vary widely among practicing neonatologists in participating countries.

Prostate cancer in the older man: conflict between tumor biology and medical advancement.

As overall life expectancy grows, clinicians will be confronted more often with diseases that although devastating in the young individual, will not affect survival and possibly even quality of life for those in the older age groups. Prostate cancer is an example of this. The challenge for the physician caring for these patients is to distinguish who is at risk and how much risk so that decisions can be made regarding the propriety of prostate cancer detection and treatment of each individual. In this article, these issues are discussed in a way that helps the clinician guide older men to better decisions regarding prostate cancer detection and therapy.

Randomized, double-blind, phase 2a trial of falciparum malaria vaccines RTS,S/AS01B and RTS,S/AS02A in malaria-naive adults: safety, efficacy, and immunologic associates of protection.

BACKGROUND: To further increase the efficacy of malaria vaccine RTS,S/AS02A, we tested the RTS,S antigen formulated using the AS01B Adjuvant System (GlaxoSmithKline Biologicals). METHODS: In a double-blind, randomized trial, 102 healthy volunteers were evenly allocated to receive RTS,S/AS01B or RTS,S/AS02A vaccine at months 0, 1, and 2 of the study, followed by malaria challenge. Protected vaccine recipients were rechallenged 5 months later. RESULTS: RTS,S/AS01B and RTS,S/AS02A were well tolerated and were safe. The efficacy of RTS,S/AS01B and RTS,S/AS02A was 50% (95% confidence interval [CI], 32.9%-67.1%) and 32% (95% CI, 17.6%-47.6%), respectively. At the time of initial challenge, the RTS,S/AS01B group had greater circumsporozoite protein (CSP)-specific immune responses, including higher immunoglobulin (Ig) G titers, higher numbers of CSP-specific CD4(+) T cells expressing 2 activation markers (interleukin-2, interferon [IFN]-gamma, tumor necrosis factor-alpha, or CD40L), and more ex vivo IFN-gamma enzyme-linked immunospots (ELISPOTs) than did the RTS,S/AS02A group. Protected vaccine recipients had a higher CSP-specific IgG titer (geometric mean titer, 188 vs 73 mug/mL; P < .001), higher numbers of CSP-specific CD4(+) T cells per 10(6) CD4(+) T cells (median, 963 vs 308 CSP-specific CD4(+) T cells/10(6) CD4(+) T cells; P < .001), and higher numbers of ex vivo IFN-gamma ELISPOTs (mean, 212 vs 96 spots/million cells; P < .001). At rechallenge, 4 of 9 vaccine recipients in each group were still completely protected. CONCLUSIONS: The RTS,S/AS01B malaria vaccine warrants comparative field trials with RTS,S/AS02A to determine the best formulation for the protection of children and infants. The association between complete protection and immune responses is a potential tool for further optimization of protection. Trial registration. ClinicalTrials.gov identifier NCT00075049.

A pilot randomized, controlled trial of later treatment with a peptide-containing, synthetic surfactant for the prevention of bronchopulmonary dysplasia.

OBJECTIVE: Oxidant injury and lung inflammation in extremely premature infants are associated with the development of bronchopulmonary dysplasia. Surfactant dysfunction resulting from these events may contribute to the pathogenesis of bronchopulmonary dysplasia. Treatment with exogenous surfactant may decrease the incidence or severity of bronchopulmonary dysplasia. We conducted a masked, multicenter, multinational, randomized, controlled, pilot study to estimate the effects of treating infants at high risk for developing bronchopulmonary dysplasia with lucinactant, a synthetic, peptide-containing surfactant, on safety during dosing and the incidence of death or bronchopulmonary dysplasia. METHODS: Preterm infants between 600 and 900 g requiring mechanical ventilation and a fraction of inspired oxygen of > or =0.30 between 3 and 10 days of age were randomly assigned to receive either sham air (placebo) or 1 of 2 doses of lucinactant (90 or 175 mg/kg total phospholipid) every 48 hours to a maximum of 5 doses, if they remained on mechanical ventilation. RESULTS: Of 136 infants enrolled at 34 sites, 44 received placebo, 47 received 90 mg/kg total phospholipid, and 45 received 175 mg/kg total phospholipid. The 90 mg/kg group had a significantly higher percentage of boys (64%) compared with the placebo group (39%); no other significant differences in baseline characteristics among groups were present. Compared with placebo, both the 90 mg/kg and 175 mg/kg groups experienced a significantly higher incidence of desaturation and bradycardia during dosing. Twenty-four hours after dosing, the mean fraction of inspired oxygen was lower in both lucinactant groups (33%) compared with the placebo group (39%). The incidence of mortality or bronchopulmonary dysplasia was 66% in the placebo group, 79% in the 90 mg/kg group, and 58% in the 175 mg/kg group. These differences were not statistically significant. There were no statistical differences among groups for pneumothorax, pulmonary interstitial emphysema, intraventricular hemorrhage, periventricular leukomalacia, retinopathy of prematurity, or mortality. CONCLUSIONS: There were trends toward lower oxygen requirements and toward a lower incidence of mortality or bronchopulmonary dysplasia at 36 weeks' postmenstrual age in infants who received the higher dose of lucinactant, and this warrants further investigation.

Phase I dose escalation safety and immunogenicity trial of Plasmodium falciparum apical membrane protein (AMA-1) FMP2.1, adjuvanted with AS02A, in malaria-naïve adults at the Walter Reed Army Institute of Research.

We report the first safety and immunogenicity trial of the Plasmodium falciparum vaccine candidate FMP2.1/AS02A, a recombinant E. coli-expressed protein based upon the apical membrane antigen-1 (AMA-1) of the 3D7 clone formulated with the AS02A adjuvant. We conducted an open-label, staggered-start, dose-escalating Phase I trial in 23 malaria-naïve volunteers who received 8, 20 or 40microg of FMP2.1 in a fixed volume of 0.5mL of AS02A on a 0, 1, and 2 month schedule. Nineteen of 23 volunteers received all three scheduled immunizations. The most frequent solicited local and systemic adverse events associated with immunization were injection site pain (68%) and headache (29%). There were no significant laboratory abnormalities or vaccine-related serious adverse events. All volunteers seroconverted after second immunization as determined by ELISA. Immune sera recognized sporozoites and merozoites by immunofluorescence assay (IFA), and exhibited both growth inhibition and processing inhibition activity against homologous (3D7) asexual stage parasites. Post-immunization, peripheral blood mononuculear cells exhibited FMP2.1-specific lymphoproliferation and IFN-gamma and IL-5 ELISPOT assay responses. This is the first PfAMA-1-based vaccine shown to elicit both potent humoral and cellular immunity in humans. Encouraged by the potential of FMP1/AS02A to target host immunity against PfAMA-1 that is known to be expressed by sporozoite, hepatic and erythrocytic stages, we have initiated field trials of FMP2.1/AS02A in an endemic population in the Republic of Mali.

Common and divergent immune response signaling pathways discovered in peripheral blood mononuclear cell gene expression patterns in presymptomatic and clinically apparent malaria.

Using genome-wide expression profiles from persons either experimentally challenged with malaria-infected mosquitoes or naturally infected with Plasmodium falciparum malaria, we present details of the transcriptional changes that occur with infection and that either are commonly shared between subjects with presymptomatic and clinically apparent malaria or distinguish these two groups. Toll-like receptor signaling through NF-kappaB pathways was significantly upregulated in both groups, as were downstream genes that function in phagocytosis and inflammation, including the cytokines tumor necrosis factor alpha, gamma interferon (IFN-gamma), and interleukin-1beta (IL-1beta). The molecular program derived from these signatures illuminates the closely orchestrated interactions that regulate gene expression by transcription factors such as IRF-1 in the IFN-gamma signal transduction pathway. Modulation of transcripts in heat shock and glycolytic enzyme genes paralleled the intensity of infection. Major histocompatibility complex class I molecules and genes involved in class II antigen presentation are significantly induced in 90% of malaria-infected persons regardless of group. Differences between early presymptomatic infection and natural infection involved genes that regulate the induction of apoptosis through mitogen-activated protein (MAP) kinases and signaling pathways through the endogenous pyrogen IL-1beta, a major inducer of fever. The induction of apoptosis in peripheral blood mononuclear cells from patients with naturally acquired infection impacted the mitochondrial control of apoptosis and the activation of MAP kinase pathways centered around MAPK14 (p38alpha and p38beta). Our findings confirm and extend findings regarding aspects of the earliest responses to malaria infection at the molecular level, which may be informative in elucidating how innate and adaptive immune responses may be modulated in different stages of infection.