Update rules and references for computational model variables.

ST6GALNAC1 induces migratory properties of colon cancer cells.

IL-13 and CCL17 induce ST6GALNAC1 and sTn expression in SW480 colon cancer cells

Expression of macrophage-associated markers in inflamed and CACC tissues compared to controls.

The serious mental illness (SMI) phenotype is marked by several different symptom domains and biomedical challenges. The nature of SMI renders in-person assessment challenging, due to problems in event recall, response biases, lack of experience in real-world functional domains, and difficulties identifying informants. Digital strategies offer a promising alternative to in-person assessments and allow for remote delivery of cognitive and social cognitive assessments in addition to continuous momentary assessment of activities, moods, symptoms, expressions, experiences, and psychophysiological variables. Remote assessments of mood, emotion, behavior, cognition, and self-assessment have been successfully collected across various SMI conditions. Both active (paging and triggered observations of facial and vocal expressions) and passive (global positioning, actigraphy) methods have been deployed remotely, similarly to in-person assessments previously conducted in the laboratory. Advanced strategies in data analysis are used to examine this information and to guide the development of newer advances in assessment of phenotypic variation in SMI.

OBJECTIVES:Disability is common in bipolar disorder (BD) and predicted by persistent sadness. We used ecological momentary assessment (EMA) to examine daily activities in people with BD and schizophrenia. We classified activities as productive, unproductive, or passive recreation, relating them to momentary sadness, location, and social context.METHODS:71 people with BD and 102 people with schizophrenia were sampled 3 times/day for 30 days with an EMA survey. Each survey asked where they were, with whom, what they were doing, and if they were sad.RESULTS:People with BD were home more than 50% of the time. There were no differences in prevalence of activity types across diagnoses. People with BD were less likely to report only one activity since the prior survey, but the most surveys still reported only one. For both groups, sadness and being home and alone since the last survey was associated with less productive activity and more passive recreation.CONCLUSIONS:Participants with BD and schizophrenia manifested high levels of unproductive and passive activities, predicted by momentary sadness. These activity patterns are consistent with descriptions of avolition and they minimally differentiated people with BD and schizophrenia. Previous reports of negative symptoms in BD may have been identifying these behaviors.

BACKGROUND:People with schizophrenia often experience poor health, leading to shortened lifespans. The health of people with schizophrenia may be further exacerbated by increased sedentary behavior, which independently predicts health risk in the general population. However, the prevalence and patterns of objectively measured sedentary behavior in schizophrenia have not been studied extensively on a momentary basis.METHODS:Activity of 100 patients with schizophrenia was compared to that of healthy controls (HC; n=71) using ecological momentary assessment (EMA). EMA provides real-time, real-world monitoring of behavior. We sampled behavior seven times per day for seven days, quantifying active versus inactive behaviors and four different movement patterns (recumbent, seated, standing, and moving). Due to different employment rates between samples, we focused on surveys completed at home.RESULTS:Four of the five most commonly reported activities for participants with schizophrenia involved sitting or lying down. When considering activity during the last hour, participants with schizophrenia were more likely to be sitting or pacing and less likely to be standing than HC. If participants with schizophrenia only did one thing in the last hour, it was more likely to involve sitting and less likely to involve standing compared to HC.DISCUSSION:People with schizophrenia were significantly more likely to be seated and less likely to be standing or active during the past hour than HC, despite high frequencies of seated behaviors in the HC as well. The adverse health consequences of sitting for extended periods may be especially relevant for people with schizophrenia and likely contribute to premature mortality in this population.

Patients weaned from immunosuppressive drugs can reject their graft after years of stability, often after an infection. We have modeled this in mice: infection with Listeria monocytogenes (Lm) at the maintenance phase of tolerance can precipitate rejection of a cardiac allograft. Here, we investigated which alloreactive Tconvs may mediate rejection after Lm infection. To track the function of allospecific Tconvs, we seeded tracer TCR75 cells, which recognize I-Ab-restricted donor Kd peptide, into B6 mice prior to Balb/c cardiac transplantation with or without tolerance induction by anti-CD154 + Balb/c splenocytes. ≥35 days post-transplantation, TCR75 cells persisting in tolerant mice developed a PD-1hi CD127lo exhausted-like phenotype and expressed the anergy markers FR4 and CD73. TCR75 cells were dysfunctional, exhibiting 10-fold less recall expansion compared to memory cells and lacked IFNγ and TNF production upon re-stimulation. Intriguingly, TCR75 cells in tolerant hosts remained dysfunctional after Lm infection, suggesting that they may not participate in infection-triggered rejection. Having found that programming T cell dysfunction in tolerance required persistence of the allograft for ~3 weeks, we tested whether T cells specific for alloantigens expressed transiently after transplantation, such as donor MHC Class II, remain functional during tolerance and may mediate rejection after Lm infection. We used tracer TEa cells specific for a donor Class II Eα peptide presented on I-Ab. During tolerance, TEa cells remained PD-1lo and CD73lo, and retained recall expansion and TNF production. We conclude that functional allospecific Tconvs present during tolerance may pose a previously unappreciated risk to the graft.

Abstract Patients with ulcerative colitis have an increased risk of developing colitis-associated colon cancer (CACC). Changes in glycosylation of the oncoprotein MUC1 commonly occur in chronic inflammation, including ulcerative colitis, and this abnormally glycosylated MUC1 promotes cancer development and progression. It is not known what causes changes in glycosylation of MUC1. Gene expression profiling of myeloid cells in inflamed and malignant colon tissues showed increased expression levels of inflammatory macrophage–associated cytokines compared with normal tissues. We analyzed the involvement of macrophage-associated cytokines in the induction of aberrant MUC1 glycoforms. A coculture system was used to examine the effects of M1 and M2 macrophages on glycosylation-related enzymes in colon cancer cells. M2-like macrophages induced the expression of the glycosyltransferase ST6GALNAC1, an enzyme that adds sialic acid to O-linked GalNAc residues, promoting the formation of tumor-associated sialyl-Tn (sTn) O-glycans. Immunostaining of ulcerative colitis and CACC tissue samples confirmed the elevated number of M2-like macrophages as well as high expression of ST6GALNAC1 and the altered MUC1-sTn glycoform on colon cells. Cytokine arrays and blocking antibody experiments indicated that the macrophage-dependent ST6GALNAC1 activation was mediated by IL13 and CCL17. We demonstrated that IL13 promoted phosphorylation of STAT6 to activate transcription of ST6GALNAC1. A computational model of signaling pathways was assembled and used to test IL13 inhibition as a possible therapy. Our findings revealed a novel cellular cross-talk between colon cells and macrophages within the inflamed and malignant colon that contributes to the pathogenesis of ulcerative colitis and CACC. See related Spotlight on p. 160

Cancer cells undergo changes that the immune system recognizes, and this can be leveraged for therapy. Antibodies specific for such changes can exert anti-tumor effects via multiple mechanisms, including blocking oncogenic signaling, serving as Trojan horses carrying toxic compounds, coordinating innate immune engagement for cytotoxicity through cellular and non-cellular means, and promoting antigen uptake to jumpstart adaptive immunity for durable protection. We analyzed 12 high-affinity fully human IgG1 monoclonal antibodies that recognize a tumor-specific hypoglycosylated form of Mucin-1 (MUC1) that is overexpressed in >80% of all cancers. These antibodies are unique and different from humanized murine anti-MUC1 mAbs, having undergone selection and affinity maturation in individuals receiving the MUC1-100mer peptide vaccine (Lohmueller et al. Sci. Rep. 2016). Importantly, in all vaccinated individuals that generated antibodies to MUC1, there have been no adverse events in 8 years, increasing the likelihood that as therapeutic agents they would be safe. To test their immune effector capacity, we used these human anti-MUC1 antibodies in in vitro antibody-dependent cellular cytotoxicity (ADCC), antibody-dependent cellular phagocytosis (ADCP) and complement-dependent cytotoxicity (CDC) assays with different huMUC1-expressing cell lines, immune effector cells and serum. Several of the anti-MUC1 antibodies can mediate ADCC by NK cells and ADCP by macrophages, although there was very little or no CDC function. Notably, unlike in published studies on rituximab and alemtuzumab, the amount of antibody binding to cancer cells (MUC1) did not always correlate with increased effector function.

Monoclonal antibody-based therapies are increasingly being used to treat cancer. Some mediate their therapeutic effects through modifying the function of immune cells globally, while others bind directly to tumor cells and can recruit immune effector cells through their Fc regions. As new direct-binding agents are developed, having the ability to test their Fc-mediated functions in a high-throughput manner is important for selecting antibodies with immune effector properties. Here, using monoclonal anti-CD20 antibody (rituximab) as an example and the CD20+ Raji cell line as tumor target, we describe flow cytometry-based assays for determining an antibody's capacity for mediating antibody-dependent cellular cytotoxicity (ADCC), antibody-dependent cellular phagocytosis (ADCP) and complement-dependent cytotoxicity (CDC). These assays are sensitive, reliable, affordable and avoid the use of radioactivity.

Significance Activated naïve T cells acquire a memory state that improves their ability to respond to second antigen encounter. Whether activated T cells in tolerant settings can develop memory is less clear. Using a mouse model of cardiac transplantation, we show that alloreactive T cells failed to acquire phenotypic and functional characteristics of memory cells, but instead developed cell-intrinsic hyporesponsiveness. Acquiring the dysfunctional state depended on alloantigen persistence and duration of alloantigen exposure. Following infection-dependent abrogation of established tolerance, alloreactive T cells remained dysfunctional. The resilience of the hyporesponsive state, including the inability to differentiate into memory T cells, may explain why episodes of transplant rejection in the clinic do not preclude subsequent successful weaning from immunosuppressive drugs.

Mechanisms implicated in robust transplantation tolerance at the cellular level can be broadly categorized into those that inhibit alloreactive T cells intrinsically (clonal deletion and dysfunction) or extrinsically through regulation. Here, we investigated whether additional population-level mechanisms control T cells by examining whether therapeutically induced peripheral transplantation tolerance could influence T cell populations' avidity for alloantigens. Whereas T cells with high avidity preferentially accumulated during acute rejection of allografts, the alloreactive T cells in tolerant recipients retained a low-avidity profile, comparable to naive mice despite evidence of activation. These contrasting avidity profiles upon productive versus tolerogenic stimulation were durable and persisted upon alloantigen re-encounter in the absence of any immunosuppression. Thus, peripheral transplantation tolerance involves control of alloreactive T cells at the population level, in addition to the individual cell level. Controlling expansion or eliminating high-affinity, donor-specific T cells long term may be desirable to achieve robust transplantation tolerance in the clinic.

Abstract Mucin 1 (MUC1) is a large transmembrane glycoprotein that is overexpressed and hypoglycosylated in many adenocarcinomas, including colon cancer. In the hypoglycosylated state, the peptide core of the 20aa variable number of tandem repeats (VNTR) region is exposed, allowing it to function as an altered-self ligand for antibodies and T cells. VNTR peptides have been previously used as antigens in therapeutic cancer vaccines. A clinical trial was conducted to test immunogenicity and safety of a MUC1 100mer VNTR peptide+polyICLC adjuvant vaccine in a prophylactic setting in patients with premalignant colon adenomas who were at high risk for later developing colon cancer. In this premalignant setting, where patients were expected to have fewer immunosuppressive countermeasures usually present in patients with cancer, nearly half of the individuals generated IgG antibodies with no noted adverse effects. Because the antibody response was isotype-switched, it suggested simultaneous T cell activation. To determine whether changes in T cell clonal abundance following immunization could be detected, we sequenced and analyzed TCRβ repertoires from PBMCs of 21 antibody-responders collected before and after both primary and one-year booster vaccinations. Of the patients analyzed, we identified 8 TCRβ sequences from three patients that were significantly elevated after both priming and boosting immunizations, potentially identifying T cell clones that expanded in response to the vaccine. 16 TCRβ sequences from four individuals were significantly decreased at both time points, potentially identifying T cell clones that left circulation to participate in immune responses in secondary lymphoid organs or tissues. The timing of blood collection at two weeks post immunization may have been too late to allow us to detect all of the vaccine-expanded clones before they left circulation. In summary, we found 24 TCRβ CDR3 sequences from 7/21 vaccine responders that significantly changed in frequency after both primary and booster vaccinations. TCR sequencing studies from patients' T cells expanded in vitro with MUC1 peptide will be performed to determine if they overlap with those sequenced ex vivo. Citation Format: Michelle L. Miller, Jason Lohmueller, John R. McKolanis, Robert Schoen, Olivera J. Finn. TCRβ repertoire analysis from a prophylactic MUC1 cancer vaccine trial [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2018; 2018 Apr 14-18; Chicago, IL. Philadelphia (PA): AACR; Cancer Res 2018;78(13 Suppl):Abstract nr 5643.

Despite recent evidence of improved graft outcomes and safety, the high incidence of early acute cellular rejection with belatacept, a high-affinity CTLA4-Ig, has limited its use in clinical transplantation. Here we define how the incomplete control of endogenous donor-reactive memory T cells results in belatacept-resistant rejection in an experimental model of BALB/c.2W-OVA donor heart transplantation into C57BL/6 recipients presensitized to donor splenocytes. These sensitized mice harbored modestly elevated numbers of endogenous donor-specific memory T cells and alloantibodies compared with naive recipients. Continuous CTLA4-Ig treatment was unexpectedly efficacious at inhibiting endogenous graft-reactive T cell expansion but was unable to inhibit late CD4+ and CD8+ T cell infiltration into the allografts, and rejection was observed in 50% of recipients by day 35 after transplantation. When CTLA4-Ig was combined with the sphingosine 1-phosphate receptor-1 (S1PR1) functional antagonist FTY720, alloantibody production was inhibited and donor-specific IFN-γ-producing T cells were reduced to levels approaching nonsensitized tolerant recipients. Late T cell recruitment into the graft was also restrained, and graft survival improved with this combination therapy. These observations suggest that a rational strategy consisting of inhibiting memory T cell expansion and trafficking into the allograft with CTLA4-Ig and FTY720 can promote allograft survival in allosensitized recipients.

PURPOSE OF REVIEW:It has long been considered that tolerance in a transplant recipient is a binary all-or-none state: either the graft is accepted without immunosuppression identifying the recipient as tolerant, or the recipient rejects the graft and is not tolerant. This tolerance paradigm, however, does not accurately reflect data emerging from animal models and patients and requires revision. RECENT FINDINGS:It is becoming appreciated that there may be different gradations in the quality of tolerance based on underlying cellular mechanisms of immunological tolerance, and that individuals may enhance their tolerance by strengthening or combining different cellular mechanisms. Furthermore, evidence suggests that even if tolerance is lost, the loss may be only temporary, and in some circumstances tolerance can be restored. SUMMARY:Shifting our focus from an all-or-nothing tolerance paradigm to one with many shades may help us better understand how tolerance operates, and how this state may be tracked and enhanced for better patient outcomes.

Purpose of review Although elusive for many decades, transplantation tolerance can now be achieved in the clinic. This has prompted follow-up investigations into its stability and longevity, as well as into barriers to its induction, which include memory T and B cells. Recent findings Clinical observations reveal that transplantation tolerance can be induced in adult recipients and that even episodes of acute rejection do not preclude successful weaning from immunosuppression to reveal tolerance. These observations appear to conflict with the currently accepted notion that adult transplant recipients harbor high frequencies of memory human leukocyte antigen-specific T cells that are a barrier to transplantation tolerance. We discuss how these observations may be rationalized, by proposing the generation of helpless effector CD8+ T cells that cannot develop into memory, and by highlighting recent findings on the ability of transplantation tolerance to be spontaneously restored after rejection. We speculate that in individuals who develop tolerance while on immunosuppression and then experience rejection, it is this restored tolerance that is revealed upon successful weaning of immunosuppression. Summary We have reviewed clinical and experimental data to explain how transplantation tolerance may be achieved in individuals who have experienced allograft rejection.

Purpose of review Although elusive for many decades, transplantation tolerance can now be achieved in the clinic. This has prompted follow-up investigations into its stability and longevity, as well as into barriers to its induction, which include memory T and B cells. Recent findings Clinical observations reveal that transplantation tolerance can be induced in adult recipients and that even episodes of acute rejection do not preclude successful weaning from immunosuppression to reveal tolerance. These observations appear to conflict with the currently accepted notion that adult transplant recipients harbor high frequencies of memory human leukocyte antigen-specific T cells that are a barrier to transplantation tolerance. We discuss how these observations may be rationalized, by proposing the generation of helpless effector CD8(+) T cells that cannot develop into memory, and by highlighting recent findings on the ability of transplantation tolerance to be spontaneously restored after rejection. We speculate that in individuals who develop tolerance while on immunosuppression and then experience rejection, it is this restored tolerance that is revealed upon successful weaning of immunosuppression. Summary We have reviewed clinical and experimental data to explain how transplantation tolerance may be achieved in individuals who have experienced allograft rejection.