Conserved transcriptional connectivity of regulatory T cells in the tumor microenvironment informs new combination cancer therapy strategies.

While regulatory T (Treg) cells are traditionally viewed as professional suppressors of antigen presenting cells and effector T cells in both autoimmunity and cancer, recent findings of distinct Treg cell functions in tissue maintenance suggest that their regulatory purview extends to a wider range of cells and is broader than previously assumed. To elucidate tumoral Treg cell 'connectivity' to diverse tumor-supporting accessory cell types, we explored immediate early changes in their single-cell transcriptomes upon punctual Treg cell depletion in experimental lung cancer and injury-induced inflammation. Before any notable T cell activation and inflammation, fibroblasts, endothelial and myeloid cells exhibited pronounced changes in their gene expression in both cancer and injury settings. Factor analysis revealed shared Treg cell-dependent gene programs, foremost, prominent upregulation of VEGF and CCR2 signaling-related genes upon Treg cell deprivation in either setting, as well as in Treg cell-poor versus Treg cell-rich human lung adenocarcinomas. Accordingly, punctual Treg cell depletion combined with short-term VEGF blockade showed markedly improved control of PD-1 blockade-resistant lung adenocarcinoma progression in mice compared to the corresponding monotherapies, highlighting a promising factor-based querying approach to elucidating new rational combination treatments of solid organ cancers.

A Distinct Function of Regulatory T Cells in Tissue Protection.

Regulatory T (Treg) cells suppress immune responses to a broad range of non-microbial and microbial antigens and indirectly limit immune inflammation-inflicted tissue damage by employing multiple mechanisms of suppression. Here, we demonstrate that selective Treg cell deficiency in amphiregulin leads to severe acute lung damage and decreased blood oxygen concentration during influenza virus infection without any measureable alterations in Treg cell suppressor function, antiviral immune responses, or viral load. This tissue repair modality is mobilized in Treg cells in response to inflammatory mediator IL-18 or alarmin IL-33, but not by TCR signaling that is required for suppressor function. These results suggest that, during infectious lung injury, Treg cells have a major direct and non-redundant role in tissue repair and maintenance-distinct from their role in suppression of immune responses and inflammation-and that these two essential Treg cell functions are invoked by separable cues.

The sphingosine 1-phosphate receptor S1P2 maintains the homeostasis of germinal center B cells and promotes niche confinement.

Mice deficient in sphingosine 1-phosphate receptor type 2 (S1P(2)) develop diffuse large B cell lymphoma. However, the role of S1P(2) in normal germinal center (GC) physiology is unknown. Here we show that S1P(2)-deficient GC B cells outgrew their wild-type counterparts in chronically established GCs. We found that antagonism of the kinase Akt mediated by S1P(2) and its downstream mediators Gα(12), Gα(13) and p115RhoGEF regulated cell viability and was required for growth control in chronically proliferating GCs. Moreover, S1P(2) inhibited GC B cell responses to follicular chemoattractants and helped confine cells to the GC. In addition, S1P(2) overexpression promoted the centering of activated B cells in the follicle. We suggest that by inhibiting Akt activation and migration, S1P(2) helps restrict GC B cell survival and localization to an S1P-low niche at the follicle center.

Immune complex relay by subcapsular sinus macrophages and noncognate B cells drives antibody affinity maturation.

Subcapsular sinus (SCS) macrophages capture antigens from lymph and present them intact for B cell encounter and follicular delivery. However, the properties of SCS macrophages are poorly defined. Here we show SCS macrophage development depended on lymphotoxin-alpha1beta2, and the cells had low lysosomal enzyme expression and retained opsonized antigens on their surface. Intravital imaging revealed immune complexes moving along macrophage processes into the follicle. Moreover, noncognate B cells relayed antigen opsonized by newly produced antibodies from the subcapsular region to the germinal center, and affinity maturation was impaired when this transport process was disrupted. Thus, we characterize SCS macrophages as specialized antigen-presenting cells functioning at the apex of an antigen transport chain that promotes humoral immunity.

Loss of signalling via Gα13 in germinal centre B-cell-derived lymphoma.

Germinal centre B-cell-like diffuse large B-cell lymphoma (GCB-DLBCL) is a common malignancy, yet the signalling pathways that are deregulated and the factors leading to its systemic dissemination are poorly defined. Work in mice showed that sphingosine-1-phosphate receptor-2 (S1PR2), a Gα12 and Gα13 coupled receptor, promotes growth regulation and local confinement of germinal centre B cells. Recent deep sequencing studies of GCB-DLBCL have revealed mutations in many genes in this cancer, including in GNA13 (encoding Gα13) and S1PR2 (refs 5,6, 7). Here we show, using in vitro and in vivo assays, that GCB-DLBCL-associated mutations occurring in S1PR2 frequently disrupt the receptor's Akt and migration inhibitory functions. Gα13-deficient mouse germinal centre B cells and human GCB-DLBCL cells were unable to suppress pAkt and migration in response to S1P, and Gα13-deficient mice developed germinal centre B-cell-derived lymphoma. Germinal centre B cells, unlike most lymphocytes, are tightly confined in lymphoid organs and do not recirculate. Remarkably, deficiency in Gα13, but not S1PR2, led to germinal centre B-cell dissemination into lymph and blood. GCB-DLBCL cell lines frequently carried mutations in the Gα13 effector ARHGEF1, and Arhgef1 deficiency also led to germinal centre B-cell dissemination. The incomplete phenocopy of Gα13- and S1PR2 deficiency led us to discover that P2RY8, an orphan receptor that is mutated in GCB-DLBCL and another germinal centre B-cell-derived malignancy, Burkitt's lymphoma, also represses germinal centre B-cell growth and promotes confinement via Gα13. These findings identify a Gα13-dependent pathway that exerts dual actions in suppressing growth and blocking dissemination of germinal centre B cells that is frequently disrupted in germinal centre B-cell-derived lymphoma.

S1PR2 links germinal center confinement and growth regulation.

Germinal centers (GCs) are sites of rapid B-cell proliferation and somatic mutation. These ovoid structures develop within the center of follicles and grow to a stereotypic size. The cell migration and interaction dynamics underlying GC B-cell selection events are currently under intense scrutiny. In recent study, we identified a role for a migration inhibitory receptor, S1PR2, in promoting GC B-cell confinement to GCs. S1PR2 also dampens Akt activation and deficiency in S1PR2 or components of its signaling pathway result in a loss of growth control in chronically stimulated mucosal GCs. Herein, we detail present understanding of S1PR2 and S1P biology as it pertains to GC B cells and place this information in the context of a current model of GC function.

Etrasimod for the Treatment of Ulcerative Colitis: Analysis of Infection Events From the ELEVATE UC Clinical Program.

BACKGROUND AND AIMS: Infections are a safety concern in patients with ulcerative colitis (UC). Etrasimod is an oral, once-daily (QD), selective sphingosine 1phosphate (S1P)1,4,5 receptor modulator for the treatment of moderately to severely active UC. It leads to selective and reversible lymphocyte sequestration, and partial peripheral lymphocyte count decrease. We report infection events from the phase 3 ELEVATE program. METHODS: Proportions, incidence rates (IRs; per 100 patient-years) and descriptive analyses of all, serious, severe, herpes zoster, and opportunistic infections are reported in the Pivotal UC cohort (ELEVATE UC 52 and ELEVATE UC 12). Cox regression models evaluated potential baseline risk factors. RESULTS: In this analysis (n=787), proportions (IRs) of all infection events were similar for patients receiving etrasimod 2 mg QD (18.8% [41.1]) or placebo (17.7% [49.0]). Serious infections occurred in three (0.6%) and five (1.9%) patients receiving etrasimod and placebo, respectively. Two herpes zoster events were reported in each group (etrasimod: 0.4%; placebo: 0.8%); all localized and non-serious. One opportunistic infection event was reported in each group. No patient with an absolute lymphocyte count (ALC) <0.2 × 109/L reported serious/severe or opportunistic infections; no baseline risk factors were identified for such events. No deaths occurred. CONCLUSIONS: Patients receiving etrasimod demonstrated no increased risk of infection. The incidence of serious infections and herpes zoster was similar in each group. Among patients receiving etrasimod, no association between ALC <0.5 × 109/L and infection events was observed. Longer-term follow-up will further characterize the etrasimod safety profile.

Not All About the Effort? A Comparison of Playing Intensities During Winning and Losing Game Quarters in Basketball.

PURPOSE: To compare peak and average intensities encountered during winning and losing game quarters in basketball players. METHODS: Eight semiprofessional male basketball players (age = 23.1 [3.8] y) were monitored during all games (N = 18) over 1 competitive season. The average intensities attained in each quarter were determined using microsensors and heart-rate monitors to derive relative values (per minute) for the following variables: PlayerLoad, frequency of high-intensity and total accelerations, decelerations, changes of direction, jumps, and total inertial movement analysis events combined, as well as modified summated-heart-rate-zones workload. The peak intensities reached in each quarter were determined using microsensors and reported as PlayerLoad per minute over 15-second, 30-second, 1-minute, 2-minute, 3-minute, 4-minute, and 5-minute sample durations. Linear mixed models and effect sizes were used to compare intensity variables between winning and losing game quarters. RESULTS: Nonsignificant (P > .05), unclear-small differences were evident between winning and losing game quarters in all variables. CONCLUSIONS: During winning and losing game quarters, peak and average intensities were similar. Consequently, factors other than the intensity of effort applied during games may underpin team success in individual game quarters and therefore warrant further investigation.

Flow Cytometric Characterization of Murine B Cell Development.

Extensive studies have characterized the development and differentiation of murine B cells in secondary lymphoid organs. Antibodies secreted by B cells have been isolated and developed into well-established therapeutics. Validation of murine B cell development, in the context of autoimmune prone mice, or in mice with modified immune systems, is a crucial component of developing or testing therapeutic agents in mice and is an appropriate use of flow cytometry. Well established B cell flow cytometric parameters can be used to evaluate B cell development in the murine peritoneum, bone marrow, and spleen, but a number of best practices must be adhered to. In addition, flow cytometric analysis of B cell compartments should also complement additional readouts of B cell development. Data generated using this technique can further our understanding of wild type, autoimmune prone mouse models as well as humanized mice that can be used to generate antibody or antibody-like molecules as therapeutics.

Risk of renal impairment after treatment with ibandronate versus zoledronic acid: a retrospective medical records review.

PURPOSE: This retrospective study compared renal impairment rates in breast cancer, multiple myeloma, prostate cancer and non-small cell lung cancer patients treated with ibandronate or zoledronic acid. STUDY DESIGN: Medical records in two German oncology clinics from May 2001 to March 2006 were retrospectively reviewed. Creatinine measurements were analyzed from baseline (before bisphosphonate treatment) to last available measurement for each patient. The Cox proportional hazards model and the Andersen-Gill extension of the Cox model for multiple events analysis were used for multivariate analysis, which controlled for age, clinic site, primary cancer type, baseline SCr or GFR value, prior bisphosphonate use, concomitant use of drugs associated with acute renal failure, and renal-related comorbidities. RESULTS: Of 333 patients, 109 received ibandronate and 256 received zoledronic acid (32 patients had both drugs). Compared with ibandronate, the zoledronic acid group had a significantly better baseline renal function and fewer patients had a history of renal disease. Zoledronic acid treatment increased the relative risk (RR) and the incidence rate (IR) of renal impairment by approximately 1.5-fold in all assessed patients (all tumors) compared with ibandronate. Multivariate analysis found significantly higher hazards ratios for zoledronic acid over ibandronate (two to sixfold), after adjusting for differences in characteristics between the two treatment groups. CONCLUSIONS: In this retrospective review, patients were significantly more likely to experience renal impairment with zoledronic acid than with ibandronate.

A nonimmune function of T cells in promoting lung tumor progression.

The involvement of effector T cells and regulatory T (T reg) cells in opposing and promoting solid organ carcinogenesis, respectively, is viewed as a shifting balance between a breach versus establishment of tolerance to tumor or self-antigens. We considered that tumor-associated T cells might promote malignancy via distinct mechanisms used by T cells in nonlymphoid organs to assist in their maintenance upon injury or stress. Recent studies suggest that T reg cells can participate in tissue repair in a manner separable from their immunosuppressive capacity. Using transplantable models of lung tumors in mice, we found that amphiregulin, a member of the epidermal growth factor family, was prominently up-regulated in intratumoral T reg cells. Furthermore, T cell-restricted amphiregulin deficiency resulted in markedly delayed lung tumor progression. This observed deterrence in tumor progression was not associated with detectable changes in T cell immune responsiveness or T reg and effector T cell numbers. These observations suggest a novel "nonimmune" modality for intratumoral T reg and effector T cells in promoting tumor growth through the production of factors normally involved in tissue repair and maintenance.

Drug-Herb Interactions in the Elderly Patient with IBD: a Growing Concern.

OPINION STATEMENT: Inflammatory bowel disease (IBD), which includes conditions such as Crohn's disease and ulcerative colitis, is becoming more prevalent with the elderly being the fastest growing group. Parallel to this, there is an increasing interest in the use of complementary and alternative medicine (CAM). Nearly half of patients with IBD have used CAM at one time. The elderly patients, however, are burdened by comorbid conditions, polypharmacy, and altered functional status. With increasing use of complementary and alternative medicine in our elderly patients with IBD, it is vital for the provider to provide counsel on drug-herb potential interactions. CAM includes herbal products, diet, dietary supplements, acupuncture, and prayer. In this paper, we will review common CAM, specifically herbs, that are used in patients with IBD including the herb background, suggested use, evidence in IBD, and most importantly, potential interactions with IBD medications used in elderly patients. Most important evidence-based adverse events and drug-herb interactions are summarized. The herbs discussed include Triticum aestivum (wheat grass), Andrographis paniculata (chiretta), Boswellia serrata, tormentil, bilberry, curcumin (turmeric), Plantago ovata (blond psyllium), Oenothera biennis (evening primrose oil), germinated barley foodstuff, an herbal preparation of myrrh, chamomile and coffee extract, chios mastic gum, wormwood (absinthe, thujone), Cannabis sativa (marijuana, THC), tripterygium wilfordii (thunder god vine), Ulmus rubra (slippery elm bark), trigonella foenugraecum (fenugreek), Dioscorea mexicana (wild yam), Harpagophytum procumbens (devil's claw), ginger, cinnamon, licorice, and peppermint.

The Eph-related tyrosine kinase ligand Ephrin-B1 marks germinal center and memory precursor B cells.

Identification of germinal center (GC) B cells is typically reliant on the use of surface activation markers that exhibit a wide range of expression. Here, we identify Ephrin-B1, a ligand for Eph-related receptor tyrosine kinases, as a specific marker of mature GC B cells. The number of Ephrin-B1+ GC B cells increases during the course of an immune response with Ephrin-B1+ GC B cells displaying elevated levels of Bcl6, S1pr2, and Aicda relative to their Ephrin-B1- counterparts. We further identified a small proportion of recently dividing, somatically mutated Ephrin-B1+ GC B cells that have begun to down-regulate Bcl6 and S1pr2 and express markers associated with memory B cells, such as CD38 and EBI2. Transcriptional analysis indicates that these cells are developmentally related to memory B cells, and likely represent a population of GC memory precursor (PreMem) B cells. GC PreMem cells display enhanced survival relative to bulk GC B cells, localize near the edge of the GC, and are predominantly found within the light zone. These findings offer insight into the significant heterogeneity that exists within the GC B cell population and provide tools to further dissect signals regulating the differentiation of GC B cells.

Cost-effectiveness of enfuvirtide in HIV therapy for treatment-experienced patients in the United States.

Enfuvirtide (ENF) is the first of a new class of antiretrovirals (ARVs) known as the HIV fusion inhibitors. Two phase III studies of ENF, TORO 1 and TORO 2, demonstrated that ENF given in combination with optimized background (OB) therapy significantly improved virological response, increased the time to virological failure, and increased CD4-cell count compared with OB alone among highly treatment-experienced patients. The present study investigated the long-term clinical outcomes, costs, and cost-effectiveness of ENF. Outcomes, costs, and cost-effectiveness were estimated using a Markov model. Viral suppression and immune reconstitution were determined from the outcomes of the clinical trials. Time to immunological failure, time to AIDS-defining event (ADE), and time to death were estimated based on published mathematical models of disease progression. Costs were based on published estimates of the use and costs of ARVs, cost of managing ADEs, and cost of laboratory and other outpatient services. Cost-effectiveness was calculated as the incremental cost per year of life gained, adjusted for quality of life. The combined effects of an increase in CD4 count and delayed time to virological and immunological failure with ENF + OB were predicted to produce a mean life expectancy of 7.4 years from initiation of therapy, which was 1.8 years (1.5 quality-adjusted lifeyears [QALYs]) greater than the life expectancy associated with OB alone. The incremental cost-effectiveness of ENF + OB was estimated to be Dollars 24,604 per QALY. ENF is projected to increase time to immunological failure, delay onset of new AIDS-defining events, and increase life expectancy by more than 1.5 years among treatment-experienced HIV-infected patients. The cost-effectiveness of ENF is comparable to many existing treatment and prevention management strategies for HIV.

Cost-effectiveness of peginterferon alfa-2a (40kDa) plus ribavirin in patients with HIV and hepatitis C virus co-infection.

BACKGROUND: A multinational trial (APRICOT) showed that peginterferon alfa-2a (40kDa) plus ribavirin is efficacious for treatment of HIV-HCV co-infection. The cost-effectiveness of treating these patients with peginterferon alfa-2a/ribavirin has yet to be explored from a US societal perspective. OBJECTIVE: To predict the cost-effectiveness of peginterferon alfa-2a/ribavirin with interferon/ribavirin (IFN/RBV) or no treatment in HIV-HCV co-infected patients. STUDY DESIGN: A Markov model was constructed with liver progression estimates based on published literature. Sustained virological response and baseline characteristics of the reference case were based on APRICOT. Quality of life and costs in 2004 US dollars (US$) were based on literature estimates and discounted at 3%. RESULTS: Peginterferon alfa-2a/ribavirin compared with IFN/RBV or no treatment is predicted to increase quality-adjusted life-years (QALYs) by 0.73 and 0.94 years, respectively, in HCV-genotype-1 patients. The incremental cost-effectiveness ratio of peginterferon alfa-2a/ribavirin compared with IFN/RBV and no treatment for all patients is respectively US$ 2,082 and 5,187/QALY gained. CONCLUSIONS: Anti-HCV treatment is predicted to decrease the risk of cirrhosis and increase quality-adjusted survival of HIV-HCV co-infected patients compared with IFN/RBV and no treatment. Peginterferon alfa-2a/ribavirin's cost per QALY gained relative to these options falls within the cost-effectiveness level of many health technologies commonly adopted in the US.

Cost-effectiveness of enfuvirtide for treatment-experienced patients with HIV in Italy.

BACKGROUND: Enfuvirtide (ENF) plus an optimized background (OB) antiretroviral regimen delays virological failure (VF), reduces HIV-1 viral load, and increases CD4 count compared with OB only in pretreated patients. PURPOSE: To forecast long-term outcomes, costs, and cost-effectiveness of ENF+OB vs. OB in the Italian health care system. METHOD: A Markov model was developed and clinical trial results on viral suppression and CD4 count were linked with data from HAART-era studies of the risk of AIDS-defining events (ADEs) and death. Resource data were obtained from Italian sources on direct medical costs. Cost-effectiveness was computed as the incremental cost per quality-adjusted life year (QALY) saved. RESULTS: Patients receiving ENF+OB were projected to experience a mean time to virological failure of 1.0 years vs. 0.5 years for OB and mean time to immunological failure of 3.1 years vs. 1.3 years for OB. Life expectancy and QALYs were greater for ENF+OB than OB by 1.8 and 1.5 years, respectively. Total lifetime medical cost was euro 126,487 for ENF+OB and euro 84,416 for OB, a difference of euro 42,071 due to the cost of ENF itself (euro 18,400) and the medical costs associated with additional life expectancy (euro 23,671). The incremental cost-effectiveness of ENF+OB was euro 23,721 per life year (euro 28,669 per QALY). CONCLUSION: ENF+OB is predicted to increase life expectancy at a cost per life year that is comparable to many well-accepted therapies in Europe.

A systematic review of patient-reported outcome instruments measuring sleep dysfunction in adults.

Sleep dysfunction can manifest in several ways, ranging from insomnia to somnolence, and from disrupted sleep to lack of restful sleep. Measuring sleep dysfunction is an area of active research and there exist a number of patient-reported outcome instruments that measure various aspects of sleep dysfunction. However, these instruments have not been evaluated systematically. We used a conceptual model of sleep that included four physical domains of general interest to patients and investigators, and cover the breadth of this disorder: sleep initiation; sleep maintenance; sleep adequacy; and somnolence. We next considered the additional health-related quality-of-life (HR-QOL) domains of psychological and social functioning, progressing along the continuum to include health perceptions and opportunity. We then conducted a literature review to identify instruments and, using criteria developed by the Medical Outcomes Trust Scientific Advisory Committee, evaluated these instruments for their potential use in measuring sleep dysfunction. Twenty-two instruments were identified. Six instruments were found to include the four physical domains defined a priori (Basic Nordic Sleep Questionnaire, Leeds Sleep Evaluation Questionnaire, Medical Outcomes Study - Sleep Problems Measures, Pittsburgh Sleep Diary, Pittsburgh Sleep Quality Index, Self-Rated Sleep Questionnaire and the Sleep Dissatisfaction Questionnaire). Several additional instruments addressed at least some of the domains and thus may be useful for specific purposes. A few instruments addressed overall HR-QOL, but did not include all four domains of interest (Functional Outcomes of Sleep Questionnaire, Quality of Life in Insomniacs and the Sleep-Wake Activity Inventory). Two instruments had undergone extensive psychometric evaluation (Medical Outcomes Study - Sleep Problems Measures and Pittsburgh Sleep Quality Index), with only the latter reporting information about interpretability. Our review indicates that measuring sleep dysfunction in adults is an area of active research and that much work still needs to be completed, specifically the study of interpretability and the application of patient preferences or item response theory. The specific research focus should dictate instrument selection.

Drug Management in the Elderly IBD Patient.

OPINION STATEMENT: Managing inflammatory bowel disease (IBD) in a world of immunomodulators and biologics is complex enough, but managing the elderly IBD patient is further confounded by multiple comorbidities, polypharmacy with drug-drug interactions, and cognitive mobility/motility disturbances. Social and insurance coverage issues also always lurk in the background. All of these factors summate into a daunting challenge for the clinician. In this review, we aim to describe important considerations when prescribing to an elderly patient with IBD, taking into account costs of medications, drug interactions, the aging body's effect on pharmacokinetics, and the effect of aging on the immune system. Adverse effects and drug-drug interactions are expounded upon in detail specific for the aging adult with IBD in an effort to assist the clinician in the decision-making process.