Targeting of multiple tumor-associated antigens by individual T cell receptors during successful cancer immunotherapy.

The T cells of the immune system can target tumors and clear solid cancers following tumor-infiltrating lymphocyte (TIL) therapy. We used combinatorial peptide libraries and a proteomic database to reveal the antigen specificities of persistent cancer-specific T cell receptors (TCRs) following successful TIL therapy for stage IV malignant melanoma. Remarkably, individual TCRs could target multiple different tumor types via the HLA A∗02:01-restricted epitopes EAAGIGILTV, LLLGIGILVL, and NLSALGIFST from Melan A, BST2, and IMP2, respectively. Atomic structures of a TCR bound to all three antigens revealed the importance of the shared x-x-x-A/G-I/L-G-I-x-x-x recognition motif. Multi-epitope targeting allows individual T cells to attack cancer in several ways simultaneously. Such "multipronged" T cells exhibited superior recognition of cancer cells compared with conventional T cell recognition of individual epitopes, making them attractive candidates for the development of future immunotherapies.

Coreceptor scanning by the T cell receptor provides a mechanism for T cell tolerance.

In the thymus, high-affinity, self-reactive thymocytes are eliminated from the pool of developing T cells, generating central tolerance. Here, we investigate how developing T cells measure self-antigen affinity. We show that very few CD4 or CD8 coreceptor molecules are coupled with the signal-initiating kinase, Lck. To initiate signaling, an antigen-engaged T cell receptor (TCR) scans multiple coreceptor molecules to find one that is coupled to Lck; this is the first and rate-limiting step in a kinetic proofreading chain of events that eventually leads to TCR triggering and negative selection. MHCII-restricted TCRs require a shorter antigen dwell time (0.2 s) to initiate negative selection compared to MHCI-restricted TCRs (0.9 s) because more CD4 coreceptors are Lck-loaded compared to CD8. We generated a model (Lck come&stay/signal duration) that accurately predicts the observed differences in antigen dwell-time thresholds used by MHCI- and MHCII-restricted thymocytes to initiate negative selection and generate self-tolerance.

Dual role of the peptide-loading complex as proofreader and limiter of MHC-I presentation.

Antigen presentation via major histocompatibility complex class I (MHC-I) molecules is essential for surveillance by the adaptive immune system. Central to this process is the peptide-loading complex (PLC), which translocates peptides from the cytosol to the endoplasmic reticulum and catalyzes peptide loading and proofreading of peptide-MHC-I (pMHC-I) complexes. Despite its importance, the impact of individual PLC components on the presented pMHC-I complexes is still insufficiently understood. Here, we used stoichiometrically defined antibody-nanobody complexes and engineered soluble T cell receptors (sTCRs) to quantify different MHC-I allomorphs and defined pMHC-I complexes, respectively. Thereby, we uncovered distinct effects of individual PLC components on the pMHC-I surface pool. Knockouts of components of the PLC editing modules, namely tapasin, ERp57, or calreticulin, changed the MHC-I surface composition to a reduced proportion of HLA-A*02:01 presentation compensated by a higher ratio of HLA-B*40:01 molecules. Intriguingly, these knockouts not only increased the presentation of suboptimally loaded HLA-A*02:01 complexes but also elevated the presentation of high-affinity peptides overexpressed in the cytosol. Our findings suggest that the components of the PLC editing module serve a dual role, acting not only as peptide proofreaders but also as limiters for abundant peptides. This dual function ensures the presentation of a broad spectrum of antigenic peptides.

High-affinity CD8 variants enhance the sensitivity of pMHCI antigen recognition via low-affinity TCRs.

CD8+ T cell-mediated recognition of peptide-major histocompatibility complex class I (pMHCI) molecules involves cooperative binding of the T cell receptor (TCR), which confers antigen specificity, and the CD8 coreceptor, which stabilizes the TCR/pMHCI complex. Earlier work has shown that the sensitivity of antigen recognition can be regulated in vitro by altering the strength of the pMHCI/CD8 interaction. Here, we characterized two CD8 variants with moderately enhanced affinities for pMHCI, aiming to boost antigen sensitivity without inducing non-specific activation. Expression of these CD8 variants in model systems preferentially enhanced pMHCI antigen recognition in the context of low-affinity TCRs. A similar effect was observed using primary CD4+ T cells transduced with cancer-targeting TCRs. The introduction of high-affinity CD8 variants also enhanced the functional sensitivity of primary CD8+ T cells expressing cancer-targeting TCRs, but comparable results were obtained using exogenous wild-type CD8. Specificity was retained in every case, with no evidence of reactivity in the absence of cognate antigen. Collectively, these findings highlight a generically applicable mechanism to enhance the sensitivity of low-affinity pMHCI antigen recognition, which could augment the therapeutic efficacy of clinically relevant TCRs.

G protein-coupled receptor (GPCR) gene variants and human genetic disease.

Genetic variations in the genes encoding G protein-coupled receptors (GPCRs) can disrupt receptor structure and function, which can result in human genetic diseases. Disease-causing mutations have been reported in at least 55 GPCRs for more than 66 monogenic diseases in humans. The spectrum of pathogenic and likely pathogenic variants includes loss of function variants that decrease receptor signaling on one extreme and gain of function that may result in biased signaling or constitutive activity, originally modeled on prototypical rhodopsin GPCR variants identified in retinitis pigmentosa, on the other. GPCR variants disrupt ligand binding, G protein coupling, accessory protein function, receptor desensitization and receptor recycling. Next generation sequencing has made it possible to identify variants of uncertain significance (VUS). We discuss variants in receptors known to result in disease and in silico strategies for disambiguation of VUS such as sorting intolerant from tolerant and polymorphism phenotyping. Modeling of variants has contributed to drug development and precision medicine, including drugs that target the melanocortin receptor in obesity and interventions that reverse loss of gonadotropin-releasing hormone receptor from the cell surface in idiopathic hypogonadotropic hypogonadism. Activating and inactivating variants of the calcium sensing receptor (CaSR) gene that are pathogenic in familial hypocalciuric hypercalcemia and autosomal dominant hypocalcemia have enabled the development of calcimimetics and calcilytics. Next generation sequencing has continued to identify variants in GPCR genes, including orphan receptors, that contribute to human phenotypes and may have therapeutic potential. Variants of the CaSR gene, some encoding an arginine-rich region that promotes receptor phosphorylation and intracellular retention, have been linked to an idiopathic epilepsy syndrome. Agnostic strategies have identified variants of the pyroglutamylated RF amide peptide receptor gene in intellectual disability and G protein-coupled receptor 39 identified in psoriatic arthropathy. Coding variants of the G protein-coupled receptor L1 (GPR37L1) orphan receptor gene have been identified in a rare familial progressive myoclonus epilepsy. The study of the role of GPCR variants in monogenic, Mendelian phenotypes has provided the basis of modeling the significance of more common variants of pharmacogenetic significance.

The anti-proliferative effects of a frankincense extract in a window of opportunity phase ia clinical trial for patients with breast cancer.

PURPOSE: Boswellic acids, active components of frankincense, suppress tumor proliferation in vitro with a strong clinical trial safety profile in patients with inflammatory diseases. We performed a Phase Ia window of opportunity trial of Boswellia serrata (B. serrata) in patients with breast cancer to evaluate its biologic activity and safety. METHODS: Patients with invasive breast cancer were treated pre-operatively with B. Serrata (2400 mg/day PO) until the night before surgery for a median of 11 days (SD 6 days; range: 5-23 days). Paraffin-embedded sections from pretreatment diagnostic core biopsies and post-treatment surgical excisions were evaluated using a tunnel assay and immunohistochemistry staining with Ki-67 antibodies. A non-intervention retrospective control arm consisting of core and surgical tissue specimens from untreated patients was used to compare patients treated with B. Serrata. The change in proliferation and apoptosis between diagnostic core specimens and surgical specimens was compared between the control and treatment groups using a two-tailed paired t-test. RESULTS: Twenty-two patients were enrolled, of which 20 received treatment, and 18 had sufficient tissue for IHC. There was an increase in percent change in proliferation from core biopsy to surgical excision in the control group (n = 18) of 54.6 ± 21.4%. In the B. serrata-treated group there was a reduction in proliferation between core biopsy and excision (n = 18) of 13.8 ± 11.7%. This difference was statistically significant between the control and B. serrata-treated groups (p = 0.008). There was no difference in change in apoptosis. There were no serious adverse events related to the drug. CONCLUSION: Boswellia serrata inhibited breast cancer proliferation and was well-tolerated in a Phase Ia window of opportunity trial.

Tuning the potency and selectivity of ImmTAC molecules by affinity modulation.

T-cell-engaging bispecifics have great clinical potential for the treatment of cancer and infectious diseases. The binding affinity and kinetics of a bispecific molecule for both target and T-cell CD3 have substantial effects on potency and specificity, but the rules governing these relationships are not fully understood. Using immune mobilizing monoclonal TCRs against cancer (ImmTAC) molecules as a model, we explored the impact of altering affinity for target and CD3 on the potency and specificity of the redirected T-cell response. This class of bispecifics binds specific target peptides presented by human leukocyte antigen on the cell surface via an affinity-enhanced T-cell receptor and can redirect T-cell activation with an anti-CD3 effector moiety. The data reveal that combining a strong affinity TCR with an intermediate affinity anti-CD3 results in optimal T-cell activation, while strong affinity of both targeting and effector domains significantly reduces maximum cytokine release. Moreover, by optimizing the affinity of both parts of the molecule, it is possible to improve the selectivity. These results could be effectively modelled based on kinetic proofreading with limited signalling. This model explained the experimental observation that strong binding at both ends of the molecules leads to reduced activity, through very stable target-bispecific-effector complexes leading to CD3 entering a non-signalling dark state. These findings have important implications for the design of anti-CD3-based bispecifics with optimal biophysical parameters for both activity and specificity.

Structural basis for the killing of human beta cells by CD8(+) T cells in type 1 diabetes.

The structural characteristics of the engagement of major histocompatibility complex (MHC) class II-restricted self antigens by autoreactive T cell antigen receptors (TCRs) is established, but how autoimmune TCRs interact with complexes of self peptide and MHC class I has been unclear. Here we examined how CD8(+) T cells kill human islet beta cells in type 1 diabetes via recognition of a human leukocyte antigen HLA-A*0201-restricted glucose-sensitive preproinsulin peptide by the autoreactive TCR 1E6. Rigid 'lock-and-key' binding underpinned the 1E6-HLA-A*0201-peptide interaction, whereby 1E6 docked similarly to most MHC class I-restricted TCRs. However, this interaction was extraordinarily weak because of limited contacts with MHC class I. TCR binding was highly peptide centric, dominated by two residues of the complementarity-determining region 3 (CDR3) loops that acted as an 'aromatic-cap' over the complex of peptide and MHC class I (pMHCI). Thus, highly focused peptide-centric interactions associated with suboptimal TCR-pMHCI binding affinities might lead to thymic escape and potential CD8(+) T cell-mediated autoreactivity.

Simulation of Hydrogen Adsorption in Hierarchical Silicalite: Role of Electrostatics and Surface Chemistry.

Adsorption in nanoporous materials is one strategy that can be used to store hydrogen at conditions of temperature and pressure that are economically viable. Adsorption capacity of nanoporous materials depends on surface area which can be enhanced by incorporating a hierarchical pore structure. We report grand canonical Monte Carlo (GCMC) simulation results on the adsorption of hydrogen in hierarchical models of silicalite that incorporate 4 nm wide mesopores in addition to the 0.5 nm wide micropores at 298 K, using different force fields to model hydrogen. Our results suggest that incorporating mesopores in silicalite can enhance adsorption by at least 20% if electrostatic interactions are not included and up to 100% otherwise. Incorporating electrostatic interactions results in higher adsorption by close to 100% at lower pressures for hierarchical silicalite whereas for unmodified silicalite, it is less significant at all pressures. Hydroxylating the mesopore surface in hierarchical silicalite results in an enhancement in adsorption at pressures below 1 atm and suppression by up to 20% at higher pressures. Temperature dependence at selected pressures exhibits expected decrease in adsorption amounts at higher temperatures. These findings can be useful in the engineering, selection, and optimization of nanoporous materials for hydrogen storage.

CD8 coreceptor-mediated focusing can reorder the agonist hierarchy of peptide ligands recognized via the T cell receptor.

CD8+ T cells are inherently cross-reactive and recognize numerous peptide antigens in the context of a given major histocompatibility complex class I (MHCI) molecule via the clonotypically expressed T cell receptor (TCR). The lineally expressed coreceptor CD8 interacts coordinately with MHCI at a distinct and largely invariant site to slow the TCR/peptide-MHCI (pMHCI) dissociation rate and enhance antigen sensitivity. However, this biological effect is not necessarily uniform, and theoretical models suggest that antigen sensitivity can be modulated in a differential manner by CD8. We used two intrinsically controlled systems to determine how the relationship between the TCR/pMHCI interaction and the pMHCI/CD8 interaction affects the functional sensitivity of antigen recognition. Our data show that modulation of the pMHCI/CD8 interaction can reorder the agonist hierarchy of peptide ligands across a spectrum of affinities for the TCR.

Linking a latent variable trait-state-occasion model of emotion regulation to cognitive control.

Emotion dysregulation (ED) is a vulnerability factor for affective disorders that may originate from deficits in cognitive control (CC). Although measures of ED are often designed to assess trait-like tendencies, the extent to which such measures capture a time-varying (TV) or state-like construct versus a time-invariant (TI) or trait-like personality characteristic is unclear. The link between the TV and TI components of ED and CC is also unclear. In a 6-wave, 5-month longitudinal study, community participants (n = 1281) completed the Difficulties in Emotion Regulation Scale (DERS-16), a commonly used measure of ED and measures of CC. A latent variable (trait-state-occasion) model showed that the proportion of TI factor variance (.80) was greater than the TV factor variance (.19). Although TV factor stability was significant, the coefficients were small in magnitude. Furthermore, regression weights for the ED TI factor (average ß = -.62) were significant and larger than those for the TV factor (average ß = -.10) in predicting latent CC at each of the six-time points. These findings suggest that ED, as assessed by the DERS-16, is largely TI and this TI component is more strongly linked to CC than the TV component.

BackWards - Unveiling the brain's topographic organization of paraspinal sensory input.

Cortical reorganization and its potential pathological significance are being increasingly studied in musculoskeletal disorders such as chronic low back pain (CLBP) patients. However, detailed sensory-topographic maps of the human back are lacking, and a baseline characterization of such representations, reflecting the somatosensory organization of the healthy back, is needed before exploring potential sensory map reorganization. To this end, a novel pneumatic vibrotactile stimulation method was used to stimulate paraspinal sensory afferents, while studying their cortical representations in unprecedented detail. In 41 young healthy participants, vibrotactile stimulations at 20 Hz and 80 Hz were applied bilaterally at nine locations along the thoracolumbar axis while functional magnetic resonance imaging (fMRI) was performed. Model-based whole-brain searchlight representational similarity analysis (RSA) was used to investigate the organizational structure of brain activity patterns evoked by thoracolumbar sensory inputs. A model based on segmental distances best explained the similarity structure of brain activity patterns that were located in different areas of sensorimotor cortices, including the primary somatosensory and motor cortices and parts of the superior parietal cortex, suggesting that these brain areas process sensory input from the back in a "dermatomal" manner. The current findings provide a sound basis for testing the "cortical map reorganization theory" and its pathological relevance in CLBP.

Structure-guided stabilization of pathogen-derived peptide-HLA-E complexes using non-natural amino acids conserves native TCR recognition.

The nonpolymorphic class Ib molecule, HLA-E, primarily presents peptides from HLA class Ia leader peptides, providing an inhibitory signal to NK cells via CD94/NKG2 interactions. Although peptides of pathogenic origin can also be presented by HLA-E to T cells, the molecular basis underpinning their role in antigen surveillance is largely unknown. Here, we solved a co-complex crystal structure of a TCR with an HLA-E presented peptide (pHLA-E) from bacterial (Mycobacterium tuberculosis) origin, and the first TCR-pHLA-E complex with a noncanonically presented peptide from viral (HIV) origin. The structures provided a molecular foundation to develop a novel method to introduce cysteine traps using non-natural amino acid chemistry that stabilized pHLA-E complexes while maintaining native interface contacts between the TCRs and different pHLA-E complexes. These pHLA-E monomers could be used to isolate pHLA-E-specific T cells, with obvious utility for studying pHLA-E restricted T cells, and for the identification of putative therapeutic TCRs.

The functional connectome of 3,4-methyldioxymethamphetamine-related declarative memory impairments.

The chronic intake of 3,4-methylenedioxymethamphetamine (MDMA, "ecstasy") bears a strong risk for sustained declarative memory impairments. Although such memory deficits have been repeatedly reported, their neurofunctional origin remains elusive. Therefore, we here investigate the neuronal basis of altered declarative memory in recurrent MDMA users at the level of brain connectivity. We examined a group of 44 chronic MDMA users and 41 demographically matched controls. Declarative memory performance was assessed by the Rey Auditory Verbal Learning Test and a visual associative learning test. To uncover alterations in the whole brain connectome between groups, we employed a data-driven multi-voxel pattern analysis (MVPA) approach on participants' resting-state functional magnetic resonance imaging data. Recent MDMA use was confirmed by hair analyses. MDMA users showed lower performance in delayed recall across tasks compared to well-matched controls with moderate-to-strong effect sizes. MVPA revealed a large cluster located in the left postcentral gyrus of global connectivity differences between groups. Post hoc seed-based connectivity analyses with this cluster unraveled hypoconnectivity to temporal areas belonging to the auditory network and hyperconnectivity to dorsal parietal regions belonging to the dorsal attention network in MDMA users. Seed-based connectivity strength was associated with verbal memory performance in the whole sample as well as with MDMA intake patterns in the user group. Our findings suggest that functional underpinnings of MDMA-related memory impairments encompass altered patterns of multimodal sensory integration within auditory processing regions to a functional heteromodal connector hub, the left postcentral gyrus. In addition, hyperconnectivity in regions of a cognitive control network might indicate compensation for degraded sensory processing.

The impact of nurse navigation on timeliness to treatment for benign high-risk breast pathology.

PURPOSE: High-risk breast pathology is a breast cancer risk factor for which timely treatment is crucial. Nurse navigation programs have been implemented to minimize delays in patient care. This study evaluated nurse navigation in terms of timeliness to surgery for patients with high-risk breast pathology. METHODS: This was a single-institution, retrospective review of patients with identified high-risk breast pathology undergoing lumpectomy between January 2017 and June 2019. Patients were stratified into cohorts based on periods with and without nurse navigation. Preoperative and postoperative time to care as well as demographic and tumor characteristics were compared using univariate and multivariate analysis. RESULTS: 100 patients had assigned nurse navigators and 29 patients did not. Nurse navigation was associated with reduced time from referral to date of surgery (DOS) by 16.9 days (p = 0.003). Patients > 75 years had a shorter time to first appointment (p = 0.03), and patients with Medicare insurance had a reduced time from referral to DOS (p = 0.005). 20% of all patients were upstaged to cancer on final surgical pathology. CONCLUSION: Nurse navigation was significantly associated with decreased time to care for patients with high-risk breast pathology undergoing lumpectomy. We recommend nurse navigation programs as part of a comprehensive approach for patients with high-risk breast pathology.

Barriers to completion of expanded carrier screening in an inner city population.

PURPOSE: The American College of Medical Genetics and Genomics emphasizes a "consistent and equitable approach for offering carrier screening." At our academic center, publicly insured prenatal patients underwent universal expanded carrier screening (ECS) to promote equitable care. The aim of the study was to evaluate rates, time, and barriers to complete ECS. This was defined as post-test counseling and partner testing after a patient was found heterozygous for a pathogenic variant. METHODS: In this descriptive retrospective cohort study from 2018 to 2021, patients were offered ECS, consisting of 283 recessive and X-linked genes. Heterozygotes were contacted by genetic counselors (≤5 attempts) for education and partner testing. Rates of counseling, partner testing, diagnostic procedures, follow-up times, and barriers to completion were assessed. RESULTS: During this time, 643 women underwent ECS. Of these 643 women, 462 were heterozygotes and 326 of 462 had undergone counseling. Two hundred twenty-two of 462 partners obtained testing, with a median of 32 days from patient to partner result. Approximately 21 couples were heterozygous for the same pathogenic variant. One patient pursued diagnostic testing. CONCLUSION: ECS offers useful information; however, this study highlights significant barriers to completion. There was suboptimal patient follow-up and low partner screening, perhaps from insufficient time to educate and counsel. Future directions include implementing quality measures to ensure optimal completion.

Chronic 3,4-Methylenedioxymethamphetamine (MDMA) Use Is Related to Glutamate and GABA Concentrations in the Striatum But Not the Anterior Cingulate Cortex.

BACKGROUND: 3,4-Methylenedioxymethamphetamine (MDMA) is a widely used recreational substance inducing acute release of serotonin. Previous studies in chronic MDMA users demonstrated selective adaptations in the serotonin system, which were assumed to be associated with cognitive deficits. However, serotonin functions are strongly entangled with glutamate as well as γ-aminobutyric acid (GABA) neurotransmission, and studies in MDMA-exposed rats show long-term adaptations in glutamatergic and GABAergic signaling. METHODS: We used proton magnetic resonance spectroscopy (MRS) to measure the glutamate-glutamine complex (GLX) and GABA concentrations in the left striatum and medial anterior cingulate cortex (ACC) of 44 chronic but recently abstinent MDMA users and 42 MDMA-naïve healthy controls. While the Mescher-Garwood point-resolved-spectroscopy sequence (MEGA-PRESS) is best suited to quantify GABA, recent studies reported poor agreement between conventional short-echo-time PRESS and MEGA-PRESS for GLX measures. Here, we applied both sequences to assess their agreement and potential confounders underlying the diverging results. RESULTS: Chronic MDMA users showed elevated GLX levels in the striatum but not the ACC. Regarding GABA, we found no group difference in either region, although a negative association with MDMA use frequency was observed in the striatum. Overall, GLX measures from MEGA-PRESS, with its longer echo time, appeared to be less confounded by macromolecule signal than the short-echo-time PRESS and thus provided more robust results. CONCLUSION: Our findings suggest that MDMA use affects not only serotonin but also striatal GLX and GABA concentrations. These insights may offer new mechanistic explanations for cognitive deficits (e.g., impaired impulse control) observed in MDMA users.

Synthetic Peptides with Inadvertent Chemical Modifications Can Activate Potentially Autoreactive T Cells.

The human CD8+ T cell clone 6C5 has previously been shown to recognize the tert-butyl-modified Bax161-170 peptide LLSY(3-tBu)FGTPT presented by HLA-A*02:01. This nonnatural epitope was likely created as a by-product of fluorenylmethoxycarbonyl protecting group peptide synthesis and bound poorly to HLA-A*02:01. In this study, we used a systematic approach to identify and characterize natural ligands for the 6C5 TCR. Functional analyses revealed that 6C5 T cells only recognized the LLSYFGTPT peptide when tBu was added to the tyrosine residue and did not recognize the LLSYFGTPT peptide modified with larger (di-tBu) or smaller chemical groups (Me). Combinatorial peptide library screening further showed that 6C5 T cells recognized a series of self-derived peptides with dissimilar amino acid sequences to LLSY(3-tBu)FGTPT. Structural studies of LLSY(3-tBu)FGTPT and two other activating nonamers (IIGWMWIPV and LLGWVFAQV) in complex with HLA-A*02:01 demonstrated similar overall peptide conformations and highlighted the importance of the position (P) 4 residue for T cell recognition, particularly the capacity of the bulky amino acid tryptophan to substitute for the tBu-modified tyrosine residue in conjunction with other changes at P5 and P6. Collectively, these results indicated that chemical modifications directly altered the immunogenicity of a synthetic peptide via molecular mimicry, leading to the inadvertent activation of a T cell clone with unexpected and potentially autoreactive specificities.

Novel methods for pregnancy drug safety surveillance in the FDA Sentinel System.

PURPOSE: It is a priority of the US Food and Drug Administration (FDA) to monitor the safety of medications used during pregnancy. Pregnancy exposure registries and cohort studies utilizing electronic health record data are primary sources of information but are limited by small sample sizes and limited outcome assessment. TreeScan™, a statistical data mining tool, can be applied within the FDA Sentinel System to simultaneously identify multiple potential adverse neonatal and infant outcomes after maternal medication exposure. METHODS: We implemented TreeScan using the Sentinel analytic tools in a cohort of linked live birth deliveries and infants nested in the IBM MarketScan® Research Database. As a case study, we compared first trimester fluoroquinolone use and cephalosporin use. We used the Bernoulli and Poisson TreeScan statistics with compatible propensity score-based study designs for confounding control (matching and stratification) and used multiple propensity score models with various strategies for confounding control to inform best practices. We developed a hierarchical outcome tree including major congenital malformations and outcomes of gestational length and birth weight. RESULTS: A total of 1791 fluoroquinolone-exposed and 8739 cephalosporin-exposed mother-infant pairs were eligible for analysis. Both TreeScan analysis methods resulted in single alerts that were deemed to be due to uncontrolled confounding or otherwise not warranting follow-up. CONCLUSIONS: In this implementation of TreeScan using Sentinel analytic tools, we did not observe any new safety signals for fluoroquinolone use in the first trimester. TreeScan, with tailored or high-dimensional propensity scores for confounding control, is a valuable tool in addition to current safety surveillance methods for medications used during pregnancy.

Intraindividual phenotyping of depression in high-risk youth: An application of a multilevel hidden Markov model.

BACKGROUND: Traditionally, depression phenotypes have been defined based on interindividual differences that distinguish between subgroups of individuals expressing distinct depressive symptoms often from cross-sectional data. Alternatively, depression phenotypes can be defined based on intraindividual differences, differentiating between transitory states of distinct symptoms profiles that a person transitions into or out of over time. Such within-person phenotypic states are less examined, despite their potential significance for understanding and treating depression. METHODS: The current study used intensive longitudinal data of youths (N = 120) at risk for depression. Clinical interviews (at baseline, 4, 10, 16, and 22 months) yielded 90 weekly assessments. We applied a multilevel hidden Markov model to identify intraindividual phenotypes of weekly depressive symptoms for at-risk youth. RESULTS: Three intraindividual phenotypes emerged: a low-depression state, an elevated-depression state, and a cognitive-physical-symptom state. Youth had a high probability of remaining in the same state over time. Furthermore, probabilities of transitioning from one state to another did not differ by age or ethnoracial minority status; girls were more likely than boys to transition from a low-depression state to either the elevated-depression state or the cognitive-physical symptom state. Finally, these intraindividual phenotypes and their dynamics were associated with comorbid externalizing symptoms. CONCLUSION: Identifying these states as well as the transitions between them characterizes how symptoms of depression change over time and provide potential directions for intervention efforts.