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Immune checkpoint therapy has resulted in minimal clinical response in many pediatric cancers. We sought to understand the influence of immune checkpoint inhibition using anti-PD-1 and anti-CTLA-4 antibodies individually, in combination, and after chemotherapy on immune responses in minimal and established murine neuroblastoma models. We also sought to understand the role of the tumor microenvironment (TME) and PD-L1 expression and their alteration post-chemotherapy in our models and human tissues. PD-L1 expression was enriched in human tumor-associated macrophages and up-regulated after chemotherapy. In a murine minimal disease model, single and dual immune checkpoint blockade promoted tumor rejection, improved survival, and established immune memory with long-term anti-tumor immunity against re-challenge. In an established tumor model, only dual immune checkpoint blockade showed efficacy. Interestingly, dual immune checkpoint therapy distinctly influenced adaptive and innate immune responses, with significant increase in CD8+CD28+PD-1+ T cells and inflammatory macrophages (CD11bhiCD11c−F4/80+Ly6Chi) in tumor-draining lymph nodes. Adding chemotherapy before immunotherapy provided significant survival benefit for mice with established tumors receiving anti-PD-1 or dual immune checkpoint blockade. Our findings demonstrate anti-PD-1 and anti-CTLA-4 therapy induces a novel subset of effector T cells, and support administration of induction chemotherapy immediately prior to immune checkpoint blockade in children with high-risk neuroblastoma.

BackgroundImmunotherapy with anti-disialoganglioside dinutuximab has improved survival for children with high-risk neuroblastoma (NB) when given after induction chemotherapy and surgery. However, disease recurrence and resistance persist. Dinutuximab efficacy has not been evaluated when initiated before primary tumor removal. Using a surgical mouse model of human NB, we examined if initiating dinutuximab plus ex vivo-activated natural killer (aNK) cells before resection of the primary tumor improves survival.MethodsIn vitro, human NB cells (SMS-KCNR-Fluc, CHLA-255-Fluc) were treated with dinutuximab and/or aNK cells and cytotoxicity was measured. In vivo, NB cells (SMS-KCNR-Fluc, CHLA-255-Fluc, or COG-N-415x PDX) were injected into the kidney of NOD-scid gamma mice. Mice received eight intravenous infusions of aNK cells plus dinutuximab beginning either 12 days before or 2 days after resection of primary tumors. Tumors in control mice were treated by resection alone or with immunotherapy alone. Disease was quantified by bioluminescent imaging and survival was monitored. aNK cell infiltration into primary tumors was quantified by flow cytometry and immunohistochemistry at varying timepoints.ResultsIn vitro, aNK cells and dinutuximab were more cytotoxic than either treatment alone. In vivo, treatment with aNK cells plus dinutuximab prior to resection of the primary tumor was most effective in limiting metastatic disease and prolonging survival. aNK cell infiltration into xenograft tumors was observed after 1 day and peaked at 5 days following injection.ConclusionDinutuximab plus aNK cell immunotherapy initiated before resection of primary tumors decreases disease burden and prolongs survival in an experimental mouse model of NB. These findings support the clinical investigation of this treatment strategy during induction therapy in patients with high-risk NB.

Purpose: Immunotherapy of neuroblastoma that remains after myeloablative chemotherapy with anti-GD2 antibody dinutuximab has increased the two-year event-free and overall survival of high-risk neuroblastoma patients; however, 40% of patients develop recurrent disease during or after this treatment. To determine the potential of such antibody-based immunotherapy earlier in treatment, a mouse model was developed in which surgical resection of the primary tumor was followed by therapy of residual disease with dinutuximab combined with ex vivo–activated human natural killer (aNK) cells. Experimental Design: The effect of combining dinutuximab with human aNK cells was determined in vitro with cellular cytotoxicity and Matrigel invasion assays. The in vivo efficacy of dinutuximab and aNK cells against neuroblastoma was assessed following resection of primary tumors formed by two cell lines or a patient-derived xenograft (PDX) in immunodeficient NOD-scid gamma mice. Results: In vitro, the combination of aNK cells and dinutuximab caused cytotoxicity and decreased invasiveness of three human neuroblastoma cell lines. Treatment of mice with dinutuximab combined with aNK cells after surgical resection of primary intrarenal tumors formed by two cell lines or a PDX decreased tumor cells in liver and bone marrow as evaluated by histopathology and bioluminescence imaging. Survival of mice after resection of these tumors was most significantly increased by treatment with dinutuximab combined with aNK cells compared with that of untreated mice. Conclusions: The combination of dinutuximab and adoptively transferred human aNK cells following surgical resection of primary neuroblastomas significantly improves survival of immunodeficient mice.

// Michael D. Hadjidaniel 1, * , Sakunthala Muthugounder 1, * , Long T. Hung 1, * , Michael A. Sheard 1 , Soheila Shirinbak 1 , Randall Y. Chan 1, 3 , Rie Nakata 1 , Lucia Borriello 1 , Jemily Malvar 1 , Rebekah J. Kennedy 1 , Hiroshi Iwakura 2 , Takashi Akamizu 2 , Richard Sposto 1, 3 , Hiroyuki Shimada 1, 3 , Yves A. DeClerck 1, 3 and Shahab Asgharzadeh 1, 3 1 Children's Hospital Los Angeles, Children's Center for Cancer and Blood Diseases, Division of Hematology, Oncology and Blood & Marrow Transplantation, and The Saban Research Institute, Los Angeles, CA, USA 2 The First Department of Medicine, Wakayama Medical University, Wakayama, Japan 3 Keck School of Medicine, University of Southern California, Los Angeles, CA, USA * These authors have contributed equally to this work Correspondence to: Shahab Asgharzadeh, email: sasgharzadeh@chla.usc.edu Keywords: neuroblastoma, tumor-associated macrophages, tumor microenvironment, STAT3, MYC Received: March 17, 2017 Accepted: July 19, 2017 Published: September 16, 2017 ABSTRACT Tumor-associated macrophages (TAMs) are strongly associated with poor survival in neuroblastomas that lack MYCN amplification. To study TAM action in neuroblastomas, we used a novel murine model of spontaneous neuroblastoma lacking MYCN amplification, and observed recruitment and polarization of TAMs, which in turn enhanced neuroblastoma proliferation and growth. In both murine and human neuroblastoma cells, we found that TAMs increased STAT3 activation in neuroblastoma cells and transcriptionally up-regulated the MYC oncogene. Analysis of human neuroblastoma tumor specimens revealed that MYC up-regulation correlates with markers of TAM infiltration. In an IL6 ko neuroblastoma model, the absence of IL-6 protein had no effect on tumor development and prevented neither STAT3 activation nor MYC up-regulation. In contrast, inhibition of JAK-STAT activation using AZD1480 or the clinically admissible inhibitor ruxolitinib significantly reduced TAM-mediated growth of neuroblastomas implanted subcutaneously in NOD scid gamma mice. Our results point to a unique mechanism in which TAMs promote tumor cells that lack amplification of an oncogene common to the malignancy by up-regulating transcriptional expression of a distinct oncogene from the same gene family, and underscore the role of IL-6-independent activation of STAT3 in this mechanism. Amplification of MYCN or constitutive up-regulation of MYC protein is observed in approximately half of high-risk tumors; our findings indicate a novel role of TAMs as inducers of MYC expression in neuroblastomas lacking independent oncogene activation.

Introduction: CD19-directed chimeric antigen receptor (CAR) T cell therapy has transformed the treatment of relapsed/refractory B-cell acute lymphoblastic leukemia (ALL), inducing complete remission in 70-90% of patients. Importantly, 40% of patients receiving CD19 CAR T cell therapy develop immune effector cell-associated neurotoxicity syndrome (ICANS), which manifests clinically as confusion, delirium, aphasia and seizures. The neurologic and immune mechanisms of ICANS remain poorly understood, and identifying biomarkers of ICANS are critical to develop strategies to mitigate or prevent this serious side effect. Methods: In an ongoing prospective, longitudinal study, we report on 11 patients with relapsed ALL (ages 6-19 years, 7 males) who received CD19 CAR T cell therapy and underwent serial comprehensive assessments including multimodal magnetic resonance imaging (MRI) of the brain (anatomical, perfusion, diffusion tensor imaging and MR spectroscopy) and neuropsychological testing. Extensive neuropsychological testing of a wide range of cognitive functions was performed. Time points for data collection included: 1) at baseline, prior to lymphodepleting (LD) chemotherapy, consisting of fludarabine and cyclophosphamide, and post-CD19 CAR T cell infusion, 2) on day 10, at peak ICANS (if applicable), and 3) at day 28, upon resolution of cytokine release syndrome (CRS) and ICANS. In addition, multimodal MRI and neuropsychological tests were acquired in 14 healthy controls (ages 5-20 years, 5 males), at one time point as baseline. The MRI data were acquired on a 3T Philips MR scanner using a 32 channel head coil without the use of sedatives or contrast agents. All MRI data were processed blinded to the participant diagnosis and the order of data acquisition. Results: In our cohort of 11 patients, 7 developed cytokine release syndrome and 4 developed ICANS (Table 1). At baseline, patients relative to controls had thinner cortices across the entire brain (Fig.1A). Patients who developed ICANS, compared to those who did not, had additional cortical thinning in the frontal, anterior cingulate, anterior temporal, dorsal parietal, and posterior cingulate cortices (Fig.1B), which together constitute the dorsal attentional network. Consistent with the thinning of attentional cortices, baseline neuropsychological assessments of patients who developed ICANS relative to those who did not revealed worse scores in the measures of inattention (p=0.025), ADHD (p=0.038), and panic disorder (p=0.016), as well as impaired working memory represented by poorer performance on the backward digit span (p=0.038) and digit total (p=0.01) tasks. Regions in the dorsal attentional network demonstrated further cortical thinning on day 10 post-infusion and rebounded to baseline values by day 28 post-infusion in most, but not all patients (Fig.1B). Conclusions: MRI findings revealed that all patients demonstrated global thinning of the cortex at baseline, likely secondary to prior chemotherapy and/or radiation therapy for ALL. These findings were more pronounced in patients who later developed ICANS and were concentrated in the area of the dorsal attentional network of the brain. This was recapitulated in baseline neuropsychological assessments which revealed deficits in attention and working memory in patients who later developed ICANS. In addition, patients with ICANS had additional cortical thinning by day 10 post-CAR T cell infusion, yet had the least cortical reserve to withstand such changes. Although most patients returned to baseline cortical thickness by day 28, which was coincident with ICANS resolution, a subset of patients failed to return to baseline cortical thickness, and we predict that these may be the patients at highest risk for long term brain changes and associated cognitive disturbances. We anticipate that the combination of MRI changes in cortical thickness, especially in the dorsal attentional network, and neuropsychologic impairments at baseline could serve as predictive biomarkers for patients who develop ICANS which in turn could allow for future interventional trials designed to mitigate or prevent ICANS in at-risk individuals. Disclosures Pulsipher: Novartis: Honoraria; Jasper: Honoraria; Bellicum: Honoraria; Mesoblast: Honoraria; Miltenyi: Honoraria, Research Funding; Adaptive: Research Funding. Wayne:Kite, a Gilead Company: Research Funding; Servier: Research Funding.

Background In a prospective study with long-term follow-up, we analyzed circulating T cell subsets in patients with metastatic colorectal cancer (mCRC) in the context of primary tumor sidedness, KRAS status, and clinical outcome. Our primary goal was to investigate whether baseline levels of circulating T cell subsets serve as a potential biomarker of clinical outcome of mCRC patients treated with an anti-VEGF-based regimen. Methods The study group consisted of 36 patients with colorectal adenocarcinoma who started first-line chemotherapy with bevacizumab for metastatic disease. We quantified T cell subsets including Tregs and CD8+ T cells in the peripheral blood prior to therapy initiation. Clinical outcome was evaluated as progression-free survival (PFS), overall survival (OS), and objective response rate (ORR). Results 1) mCRC patients with KRAS wt tumors had higher proportions of circulating CD8+ cytotoxic T cells among all T cells but also higher measures of T regulatory (Treg) cells such as absolute count and a higher proportion of Tregs in the CD4+ subset. 2) A low proportion of circulating Tregs among CD4+ cells, and a high CD8:Treg ratio at initiation of VEGF-targeting therapy, were associated with favorable clinical outcome. 3) In a subset of patients with primarily right-sided mCRC, superior PFS and OS were observed when the CD8:Treg ratio was high. Conclusions The baseline level of circulating immune cells predicts clinical outcome of 1st-line treatment with the anti-VEGF angio/immunomodulatory agent bevacizumab. Circulating immune biomarkers, namely the CD8:Treg ratio, identified patients in the right-sided mCRC subgroup with favorable outcome following treatment with 1st-line anti-VEGF treatment. Electronic supplementary material The online version of this article (10.1186/s12885-019-5909-5) contains supplementary material, which is available to authorized users.

Tumor-associated macrophages can promote growth of cancers. In neuroblastoma, tumor-associated macrophages have greater frequency in metastatic versus loco-regional tumors, and higher expression of genes associated with macrophages helps to predict poor prognosis in the 60% of high-risk patients who have MYCN-non-amplified disease. The contribution of cytotoxic T-lymphocytes to anti-neuroblastoma immune responses may be limited by low MHC class I expression and low exonic mutation frequency. Therefore, we modelled human neuroblastoma in T-cell deficient mice to examine whether depletion of monocytes/macrophages from the neuroblastoma microenvironment by blockade of CSF-1R can improve the response to chemotherapy. In vitro, CSF-1 was released by neuroblastoma cells, and topotecan increased this release. In vivo, neuroblastomas formed by subcutaneous co-injection of human neuroblastoma cells and human monocytes into immunodeficient NOD/SCID mice had fewer human CD14(+) and CD163(+) cells and mouse F4/80(+) cells following CSF-1R blockade. In subcutaneous or intra-renal models in immunodeficient NSG or NOD/SCID mice, CSF-1R blockade alone did not affect tumor growth or mouse survival. However, when combined with cyclophosphamide plus topotecan, the CSF-1R inhibitor BLZ945, either without or with anti-human and anti-mouse CSF-1 mAbs, inhibited neuroblastoma growth and synergistically improved mouse survival. These findings indicate that depletion of tumor-associated macrophages from neuroblastomas can be associated with increased chemotherapeutic efficacy without requiring a contribution from T-lymphocytes, suggesting the possibility that combination of CSF-1R blockade with chemotherapy might be effective in patients who have limited anti-tumor T-cell responses.

BACKGROUND: Single agent studies targeting the tumor microenvironment in central nervous system (CNS) tumors have largely been disappointing. Combination therapies targeting various pathways and cell types may be a more effective strategy. In this phase I study, we evaluated the combination of dasatinib, lenalidomide, and temozolomide in children with relapsed or refractory primary CNS tumors. METHODS: Patients 1–21 years old with relapsed or refractory CNS tumors were eligible. Starting doses of dasatinib and lenalidomide were 65 mg/m(2)/dose twice daily and 55 mg/m(2) once daily, respectively, while temozolomide was constant at 75 mg/m(2) daily. The study followed a 3+3 phase I design, with a 4-week dose-limiting toxicity (DLT) evaluation period. Serial peripheral blood lymphocyte subsets were evaluated in consenting patients. RESULTS: Fifteen patients were enrolled and thirteen were DLT-evaluable. DLTs occurred in 5 patients, including somnolence and confusion (1 patient), hypokalemia (1 patient) and thrombocytopenia (3 patients). The maximum tolerated dose for the combination was dasatinib 65 mg/m(2) twice daily, lenalidomide 40 mg/m(2) daily, and temozolomide 75 mg/m(2) daily, for 21 days followed by 7 days rest in repeating 28-day cycles. Transient increases in natural killer effector cells and cytotoxic T-cells were seen after 1 week of treatment. One out of 6 response-evaluable patients showed a partial response. CONCLUSIONS: The combination was feasible and relatively well tolerated in this heavily pre-treated population. The most common toxicities were hematologic. Preliminary evidence of clinical benefit was seen.

Introduction: CD19-directed chimeric antigen receptor (CAR)-T cell therapy has revolutionized the treatment for B-cell acute lymphoblastic leukemia (ALL), inducing complete remission in 70-90% of highly refractory patients. Unfortunately, CAR-T cell therapy is associated with immune effector cell-associated neurotoxicity syndrome (ICANS) in 40% of patients, which presents as confusion, memory impairment, aphasia, altered level of consciousness and/or delirium. The neurobiological and immune bases of ICANS remain poorly understood, and identifying them will help develop strategies for early intervention to mitigate ICANS. Methods: From an ongoing prospective, longitudinal study, we report on the first 7 patients with relapsed ALL (age 5-19 years, 5 males) who underwent comprehensive assessments at baseline before lympho-depleting (LD) chemotherapy (fludarabine and cyclophosphamide) and infusion of CD19-directed CAR T-cells, and post-infusion, on days 10 and 28. These assessments included multimodal magnetic resonance imaging (MRI) of the brain (anatomical, perfusion, diffusion tensor imaging and MR spectroscopy), neuropsychological testing, serum measures of blood-brain barrier permeability and cytokines, and immune cell profiles in peripheral blood using mass cytometry by time-of-flight (CyTOF). We also acquired multimodal MRI and neuropsychological testing in 9 healthy controls (age 5-20 years, 7 males), once, at baseline. MRI data were acquired on a 3T Philips MR scanner using a 32 channel head coil without the use of sedatives or contrast agents and were processed blind to the diagnosis and order of data acquisition. Results: In our cohort of 7 patients, 5 developed cytokine release syndrome and 4 developed ICANS. Brain imaging findings are demonstrated in figures 1 (cortical thickness) and 2 (blood perfusion). Prior to CAR T-cell infusion patients relative to healthy controls had thinner cortex bilaterally across large portions of the brain. By post-infusion day 10, cortical thickness decreased in the postcentral gyrus (PoG) and posterior temporal lobe (pTL). Subsequently, by post-infusion day 28, cortex thickened in the PoG but continued thinning in the pTL. Patients relative to controls had lower regional cerebral blood flow (rCBF) in the thalamus, insular cortex, and cingulate gyrus, and higher rCBF in the genu of the corpus callosum (gCC). By post-infusion day 10, rCBF increased in the thalamus and decreased in the putamen and gCC. By post-infusion day 28, rCBF in the thalamus decreased and reverted towards baseline values, whereas rCBF in gCC continued to decrease away from baseline values. CyTOF analyses, as expected, showed expansion of monocytes and myeloid-derived suppressor cells by post-infusion day 10. Furthermore, in these immune cells, phosphorylation of key signaling proteins (e.g. extracellular-signal regulated kinase, ERK1/2) increased in response to external stimulation. Conclusions: Patients had widespread brain abnormalities at baseline compared to controls, likely because of prior therapies and/or underlying ALL. Post LD chemotherapy and CAR T-cell infusion, several brain abnormalities worsened by day 10 and then reverted toward baseline values by day 28. These temporal changes are generally consistent with clinically reported development of ICANS by day 10, which largely resolves by day 28. However, in certain regions brain measures progressively deviated from baseline and control values through day 28, suggesting some abnormalities associated with CAR T therapy may persist. Preliminary immune cell profiling implicates monocytes as a possible source of elevated cytokines following CAR T-cell infusion. Analysis for correlation of these findings with symptomatic ICANS and neuropsychological measures is ongoing. Patients on this study will also be followed at 6 months and 1 year to evaluate for long term neurological effects of CAR T-cell therapy. Figure 1: Cortical Thickness abnormalities in patients relative to healthy controls (1st panel); within-patient changes post-infusion (2nd, 3rd, & 4th panel). Blue & violet show decreases and orange & red show increases in cortical thickness. Figure 2: Blood perfusion abnormalities in patients relative to healthy controls (1st panel); within patient changes post infusion (2nd, 3rd, & 4th panel). Blue & violet show decreases and orange & red show increases in regional cerebral blood flow. Disclosures Pulsipher: Novartis: Consultancy, Membership on an entity's Board of Directors or advisory committees, Speakers Bureau; Jazz: Other: Education for employees; Adaptive: Membership on an entity's Board of Directors or advisory committees, Research Funding; Miltenyi: Research Funding; Bellicum: Consultancy; Amgen: Other: Lecture; CSL Behring: Membership on an entity's Board of Directors or advisory committees; Medac: Honoraria. Wayne:Spectrum Pharmaceuticals: Consultancy, Research Funding; AbbVie: Consultancy; Kite, a Gilead Company: Consultancy, Research Funding; Servier: Consultancy.

10522Background: Ch14.18 (dinutuximab) increases event free and overall survival in patients with high-risk NB when given in a regimen with GM-CSF/IL-2. However, this therapy has significant toxici...

Defects in apoptosis signaling contribute to poor outcome in pediatric acute lymphoblastic leukemia (ALL), and overexpression of antiapoptotic Bcl-2 (Bcl-2 and Bcl-XL) family proteins has been observed in ALL. ABT-737 is a small-molecule BH3-mimetic that inhibits the antiapoptotic Bcl-2 family proteins. We evaluated the cytotoxicity of ABT-737 in combination with vincristine, dexamethasone, and L-asparaginase (VXL) in 7 ALL cell lines. Multilog synergistic cytotoxicity was observed in all 7 cell lines with ABT-737 plus L-asparaginase or vincristine, and in 5 of 7 cell lines with ABT-737 plus dexamethasone or VXL. In leukemia cells, but not in normal lymphocytes, ABT-737 plus L-asparaginase induced greater mitochondrial depolarization (JC-1 staining); mitochondrial cytochrome c release; activation of Bax, Bid, and caspases (immunoblotting); and eventually apoptosis (annexin V staining) than did either drug alone. In mouse xenografts derived from patients with ALL at diagnosis (ALL-7) or at relapse (ALL-19), event-free survival (EFS) was significantly enhanced with ABT-737 plus VXL relative to VXL or ABT-737 alone (P ≤ .02). Thus, ABT-737 synergistically enhanced VXL cytotoxicity in ALL cell lines via a mitochondrial death pathway and enhanced EFS in VXL-treated mice bearing ALL xenografts. Combining VXL with a BH3-mimetic warrants clinical investigation in ALL at relapse and potentially in chemotherapy-resistant ALL subgroups.

Describes a study to measure the quality of service provided by food‐poisoning surveillance agencies in England and Wales in terms of the requirements of a representative consumer ‐ the egg producing industry ‐ adopting “egg associated” outbreak investigation reports as the reference output. Defines and makes use of four primary performance indicators: accessibility of information; completeness of evidence supplied in food‐poisoning outbreak investigation reports as to the sources of infection in “egg‐associated” outbreaks; timeliness of information published; and utility of information and advice aimed at preventing or controlling food poisoning. Finds that quality expectations in each parameter measured are not met. Examines reasons why surveillance agencies have not delivered the quality demanded. Makes use of detailed case studies to illustrate inadequacies of current practice. Attributes failure to deliver “accessibility” to a lack of recognition on the status or nature of “consumers”, combined with a self‐maintenance motivation of the part of the surveillance agencies. Finds that failures to deliver “completeness” and “utility” may result from the same defects which give rise to the lack of “accessibility” in that, failing to recognize the consumers of a public service for what they are, the agencies feel no need to provide them with the data they require. The research indicates that self‐maintenance by scientific epidemiologists may introduce biases which when combined with a politically inspired need to transfer responsibility for food‐poisoning outbreaks, skew the conduct of investigations and their conclusions. Contends that this is compounded by serious and multiple inadequacies in the conduct of investigations, arising at least in part from the lack of training and relative inexperience of investigators, the whole conditioned by interdisciplinary rivalry between the professional groups staffing the different agencies. Finds that in addition failures to exploit or develop epidemiological technologies has affected the ability of investigators to resolve the uncertainties identified. Makes recommendations directed at improving the performance of the surveillance agencies which, if adopted will substantially enhance food poisoning control efforts.

• This is a 2-year, double-blind, placebo-controlled study of 101 patients, evaluating the relative efficacy of intermittent medication (given only when the patient shows early signs of relapse) compared with moderate doses of maintenance medication for stable schizophrenic outpatients. Patients were dropped from the study if they had three prodromal episodes in 1 year or if an episode lasted more than 9 weeks. Fourteen percent of patients given maintenance treatment were dropped from the study compared with 46% of intermittently treated patients. Relapse rates were 16% for patients given maintenance treatment and 30% for intermittently treated patients, a nonsignificant difference. Intermittently treated patients were receiving significantly less medication, but there were no differences found in drug side effects. There appears to be no advantage in using the intermittent approach, but we found that the use of an early intervention strategy reduced the relapse and rehospitalization rates for these patients.

The utility and side effects of sustained-release lithium carbonate (Priadel) in a once-per-day dose regimen was investigated with 66 male delinquents, ages 17-24 years, in a double-blind study comparing the antiaggressive effect of lithium carbonate with placebo. Serum lithium levels and symptoms were determined weekly for up to eight drug-free and 12 on-medication weeks. Average daily doses of 1500-1700 mg Priadel gave 24-hour serum lithium levels in the range 0.7-0.9 mEq/liter. Principal side effects were polyuria and shakiness, with other important side effects bring hand tremor, dryness of mouth, nausea, and weakness. No lithium toxicity was observed, and diarrhea was reported infrequently. Placebo response data are presented.

Preincarceration drug-use patterns were investigated retrospectively in 58 male prisoners, average age 18.6 years, of whom 50% were White, 43% Black, and 7% Hispanic. Fifty-five percent were classified as drug-dependent, 36% as regular, and 9% as casual users of at least one drug. Classification according to numbers of "hard" drugs used regularly gave equal percentages of subjects using none, one to two, or more than two (polydrug users). The polydrug users were predominantly White and often used amphetamines or hallucinogens, while those using one to two "hard" drugs regularly were predominantly Black, eschewed hallucinogens, and preferred narcotics.

The behavioral effects of IP administration of lisuride, a non-hallucinogenic iso-lysergic acid amide analog structurally related to d-lysergic acid diethylamide (LSD), were examined in 15 cats. Ten animals were given saline or 6.25, 12.5, 25, 50, or 100 micrograms/kg of lisuride and observed for 1 h by a rater blind to dose. There was a statistically significant effect of lisuride dose on the frequency of occurrence of the behaviors limb flicking, grooming, and abortive grooming. A time-course study with five cats at the most effective lisuride dose, 50 micrograms/kg, revealed that the frequencies of occurrence of these behaviors reached a maximum during the first 2 h post dose, and were comparable to frequencies after saline by 6 h post dose. An acute tolerance study with four cats scored for 90 min post dose revealed no significant tolerance to a 50 micrograms/kg lisuride test dose administered 6, 24, or 72 h after an initial 50 micrograms/kg dose. Acute cross tolerance studies with four cats scored for 90 min after an initial dose of 50 micrograms/kg of LSD or of lisuride, followed 24 h later by 50 micrograms/kg of lisuride or LSD, revealed no significant cross tolerance. The potency of lisuride relative to LSD was evaluated in six cats that were scored for 60 min following 25 and 50 micrograms/kg of LSD and of lisuride. On a molar basis, scores after lisuride were 51% and 67% those after LSD for limb flicking and grooming. These results indicate that lisuride, a non-hallucinogenic iso-lysergic acid derivative, is a false positive in the animal behavior model for hallucinogens.

Lesions were made bilaterally in the lateral hypothalamus in ten rats and in the posteromedial hypothalamic midbrain transition in ten rats. A control group of ten rats had electrodes passed and withdran without any current. The groups of rats were given 12 min of escape conditioning in an operant conditioning situation. The telencephalon was analyzed for 5-hydroxytryptamine (5-HT) and norepinephrine (NE). Brain stems were examined microscopically for lesion site. There was a significant correlation between: (1) low 5-HT and NE in the telencephalon and both lesions, and (2) between prolongation of the escape latency and low 5-HT and NE in telencephalon with a significant difference from control rats, (P

SummaryThe serum corticosteroid response to small doses of human ACTH was studied in a group of healthy male volunteers whose endogenous ACTH production was suppressed with dexamethasone. Whereas the initial rate of rise and the time required for onset of rise of serum II-OHCS were independent of the dose of ACTH over a tenfold range (approximately 10-100 ng/kg of body weight), the maximum levels attained and the time required to reach these maxima were a direct function of the dose of ACTH employed.

The startle reflex was measured in 4 groups of 10 rats each after intraperitoneal injection of saline or 0.12, 0.25, 0.50 or 4.00 mg/kg N-N-dimethyltryptamine (DMT). Low doses (0.25 and 0.50) of DMT augmented startle but the high dose (4.0) depressed startle. This biphasic dose-response relationship is consistent with the hypothesis that startle is enhanced when midbrain raphe neurons are inhibited but depressed when cells post-synaptic to raphe neurons are also inhibited.

ONLY a limited number of experiments have been designed to evaluate the effects of noise on aggression. As animal models of aggression are amenable to pharmacological and physiological analysis we have investigated the effect of noise on aggression in rats and have found an interesting non-monotonic relationship, with an increase in aggression at moderate noise levels but a decrease at high levels. The aggressive behaviour chosen for the present experiments was shock-elicited aggression in the rat. Two rats were paired in a small enclosure and subjected to a series of footshocks which elicit fighting, depending on the intensity, frequency and duration of electric shock1,2. This is a well documented and highly reliable form of aggressive behaviour that is usually considered a form of irritable aggression3.

In Experiment 1, body weights of rats fed a powdered tryptophan-free (TF) diet decreased monotonically during a 13-day period. Control animals fed the same diet supplemented with 0.5% l-tryptophan gained weight. The groups did not differ significantly in acoustic startle amplitude measured at 2, 4, 6, 7, 9, 11, and 13 days despite a 28% decrease in whole-brain serotonin in the TF rats. In Experiment 2, daily intubation of rats with a syrup form of each diet maintained the two groups' body weights at comparable levels. TF diet intubation decreased whole-brain serotonin by 64% and produced significantly elevated startle amplitudes, which returned to control levels when 0.5% l-tryptophan was added to the diet. Changes in whole-brain serotonin level preceded changes in startle amplitude by several days. In Experiment 3, acute injections of 125 mg/kg l-tryptophan significantly reduced the startle amplitude of TF diet intubated rats and significantly raised their brain serotonin levels. The results show that acoustic startle reflex is increased by a TF diet, provided the animals receive adequate nourishment, and suggest that this facilitation may result from depletion of brain serotonin.

Lithium has become a widely accepted treatment for manic-depressive psychosis. It is dramatically effective for many cases of mania and is useful in the prevention of manic and depressive episodes. Hyperaggressiveness and hypersexuality are frequent components of manic-depressive illness and abate under the influence of lithium. A brief review is presented of the behavioral and biochemical pharmacology of lithium. This documents the inhibitory role which lithium can play in several examples of animal aggressive behavior including pain-elicited aggression, mouse killing in rats, isolation-induced aggression in mice, p-chlorophenylalanine-induced aggression in rats, and hypothalamically induced aggression in cats. The use of lithium to control human aggressive behavior has resulted in controversial findings. In epileptic conditions, improvement has been reported in interseizure aggressivity, but other reports indicate the possibility of increased seizures. Improvement in aggressive behavior in childhood has occasionally been reported as well as in emotionally unstable character disorders in young female patients. Te was a single blind study and the other a large but uncontrolled study. Both studies reported an improvement in aggressiveness as indicated by fewer recorded reports (tickets) for fighting. The final study reported is a study of 12 male delinquents age 16 to 23. They received lithium or placebo for 4 months inside an institution and then a trial of lithium for 1 to 12 months on an outpatient basis. Analysis of results in terms of the number of aggressive antisocial acts showed fewer serious aggressive episodes when the lithium level was between 0.6 and 1 meq/liter than when it was between 0.0 and 0.6 meq/liter. These results must be viewed with caution and are only suggestive since the study was not double blind.

In a series of experiments the effects of amphetamine, phentolamine, apomorphine, amphetamine plus apomorphine, Clonidine, propranolol phenoxybenzamine piperoxane on shock elicited fighting (SEF) in rats were investigated. Results showed no significant effects with amphetamine, apomorphine, apomorphine and amphetamine, phenoxybenzamine or phentolamine. There was a significant inhibition of fighting with Clonidine and propranolol. An increase in fighting was seen with a low dose of piperoxane but an inhibition at a high dose.

Male Sprague-Dawley rats were treated with p-chlorophenylalanine (pCPA) and 15–24 hr later their behavior was rated in an observation chamber. Their behavior was compared with rats which had lesions in the dorsal and median raphe nuclei to deplete brain serotonin. In spite of a comparable lowering of brain serotonin, lesioned rats did not display exaggerated sexual or aggressive behavior.

Awake, unrestrained rats were stimulated electrically via chronic electrodes implanted in the region of serotonin-containing neurones in the midbrain raphe. Behavioral observations showed a failure of the usual habituation to reptitive sensory stimuli (as indicated by a persistence of the startle response) without any evidence of motor excitation, or somnolence. Para-chlorophenylalanine and reserpine abolish this effect of raphe stimulation. Rental temperatures showed a rise of 1 – 1.5°C during the course of stimulation.

LITHIUM has been shown to be effective in the treatment of mania1–3, and it reduces aggressive behaviour in Siamese fighting fish and small rodents4. I have investigated the action of lithium on aggressive behaviour in rats subjected to foot shock. This type of aggression has been well described already5,6.

LITHIUM has been shown to be effective in the manic and hypomanic phase of manic-depressive psychosis1–3, and to some extent to prevent manic episodes and, to a lesser degree, depressive episodes4–6. Manic depressive disorders are frequently characterized by hyperaggressive and hypersexual activity. In animals lithium has been reported to have an inhibitory effect on aggressive behaviour7,8 and on the sexual and aggressive behaviour seen with p-chlorophenylalanine9. I therefore conducted a clinical trial of lithium on human aggressive behaviour.