PvDBPII elicits multiple antibody-mediated mechanisms that reduce growth in a Plasmodium vivax challenge trial.

The receptor-binding domain, region II, of the Plasmodium vivax Duffy binding protein (PvDBPII) binds the Duffy antigen on the reticulocyte surface to mediate invasion. A heterologous vaccine challenge trial recently showed that a delayed dosing regimen with recombinant PvDBPII SalI variant formulated with adjuvant Matrix-MTM reduced the in vivo parasite multiplication rate (PMR) in immunized volunteers challenged with the Thai P. vivax isolate PvW1. Here, we describe extensive analysis of the polyfunctional antibody responses elicited by PvDBPII immunization and identify immune correlates for PMR reduction. A classification algorithm identified antibody features that significantly contribute to PMR reduction. These included antibody titre, receptor-binding inhibitory titre, dissociation constant of the PvDBPII-antibody interaction, complement C1q and Fc gamma receptor binding and specific IgG subclasses. These data suggest that multiple immune mechanisms elicited by PvDBPII immunization are likely to be associated with protection and the immune correlates identified could guide the development of an effective vaccine for P. vivax malaria. Importantly, all the polyfunctional antibody features that correlated with protection cross-reacted with both PvDBPII SalI and PvW1 variants, suggesting that immunization with PvDBPII should protect against diverse P. vivax isolates.

Anti-S-layer monoclonal antibodies impact Clostridioides difficile physiology.

Clostridioides difficile (C. difficile), a gram-positive anaerobic and spore-forming bacterium, is the leading cause of nosocomial antibiotic-associated diarrhea in adults which is characterized by high levels of recurrence and mortality. Surface (S)-layer Protein A (SlpA), the most abundantly expressed protein on the bacterial surface, plays a crucial role in the early stages of infection although the nature of its involvement in C. difficile physiology is yet to be fully understood. Anti-S-layer antibodies have been identified in the sera of convalescent patients and have been correlated with improved outcomes of C. difficile infection (CDI). However, the precise mechanisms by which anti-S-layer antibodies confer protection to the host remain unknown. In this study, we report the first monoclonal antibodies (mAbs) targeting the S-layer of reference strain 630. Characterization of these mAbs unraveled important roles for the S-layer protein in growth, toxin secretion, and biofilm formation by C. difficile, with differential and even opposite effects of various anti-SlpA mAbs on these functions. Moreover, one anti-SlpA mAb impaired C. difficile growth and conferred sensitivity to lysozyme-induced lysis. The results of this study show that anti-S-layer antibody responses can be beneficial or harmful for the course of CDI and provide important insights for the development of adequate S-layer-targeting therapeutics.

Antigen self-anchoring onto bacteriophage T5 capsid-like particles for vaccine design.

The promises of vaccines based on virus-like particles stimulate demand for universal non-infectious virus-like platforms that can be efficiently grafted with large antigens. Here, we harnessed the modularity and extreme affinity of the decoration protein pb10 for the capsid of bacteriophage T5. SPR experiments demonstrated that pb10 fused to mCherry or to the model antigen ovalbumin (Ova) retained picomolar affinity for DNA-free T5 capsid-like particles (T5-CLPs), while cryo-EM studies attested to the full occupancy of the 120 capsid binding sites. Mice immunization with CLP-bound pb10-Ova chimeras elicited strong long-lasting anti-Ova humoral responses involving a large panel of isotypes, as well as CD8+ T cell responses, without any extrinsic adjuvant. Therefore, T5-CLP constitutes a unique DNA-free bacteriophage capsid able to display a regular array of large antigens through highly efficient chemical-free anchoring. Its ability to elicit robust immune responses paves the way for further development of this novel vaccination platform.

A monoclonal antibody collection for C. difficile typing ?

Clostridioides difficile is the leading cause of antibiotic-associated diarrhea and pseudomembranous colitis in adults. Various C. difficile strains circulate currently, associated with different outcomes and antibiotic resistance profiles. However, most studies still focus on the reference strain 630 that does not circulate anymore, partly due to the lack of immunological tools to study current clinically important C. difficile PCR ribotypes. The goal of this study was to generate monoclonal antibodies recognizing various epidemic ribotypes of C. difficile. To do so, we immunized mice expressing human variable antibody genes with the Low Molecular Weight (LMW) subunit of the surface layer protein SlpA from various C. difficile strains. Monoclonal antibodies purified from hybridomas bound LMW with high-affinity and whole bacteria from current C. difficile ribotypes with different cross-specificities. This first collection of anti-C. difficile mAbs represent valuable tools for basic and clinical research.

Interrogating Aptamer Chemical Space Through Modified Nucleotide Substitution Facilitated by Enzymatic DNA Synthesis.

Chemical modification of aptamers is an important step to improve their performance and stability in biological media. This can be performed either during their identification (mod-SELEX) or after the in vitro selection process (post-SELEX). In order to reduce the complexity and workload of the post-SELEX modification of aptamers, we have evaluated the possibility of improving a previously reported, chemically modified aptamer by combining enzymatic synthesis and nucleotides bearing bioisosteres of the parent cubane side-chains or substituted cubane moieties. This method lowers the synthetic burden often associated with post-SELEX approaches and allowed to identify one additional sequence that maintains binding to the PvLDH target protein, albeit with reduced specificity. In addition, while bioisosteres often improve the potency of small molecule drugs, this does not extend to chemically modified aptamers. Overall, this versatile method can be applied for the post-SELEX modification of other aptamers and functional nucleic acids.

SCRIB controls apical contractility during epithelial differentiation.

Although mutations in the SCRIB gene lead to multiple morphological organ defects in vertebrates, the molecular pathway linking SCRIB to organ shape anomalies remains elusive. Here, we study the impact of SCRIB-targeted gene mutations during the formation of the gut epithelium in an organ-on-chip model. We show that SCRIB KO gut-like epithelia are flatter with reduced exposed surface area. Cell differentiation on filters further shows that SCRIB plays a critical role in the control of apical cell shape, as well as in the basoapical polarization of myosin light chain localization and activity. Finally, we show that SCRIB serves as a molecular scaffold for SHROOM2/4 and ROCK1 and identify an evolutionary conserved SHROOM binding site in the SCRIB carboxy-terminal that is required for SCRIB function in the control of apical cell shape. Our results demonstrate that SCRIB plays a key role in epithelial morphogenesis by controlling the epithelial apical contractility during cell differentiation.

The SET and ankyrin domains of the secreted Legionella pneumophila histone methyltransferase work together to modify host chromatin.

IMPORTANCE: Legionella pneumophila is an intracellular bacterium responsible of Legionnaires' disease, a severe pneumonia that is often fatal when not treated promptly. The pathogen's ability to efficiently colonize the host resides in its ability to replicate intracellularly. Essential for intracellular replication is translocation of many different protein effectors via a specialized secretion system. One of them, called RomA, binds and directly modifies the host chromatin at a unique site (tri-methylation of lysine 14 of histone H3 [H3K14me]). However, the molecular mechanisms of binding are not known. Here, we resolve this question through structural characterization of RomA together with the H3 peptide. We specifically reveal an active role of the ankyrin repeats located in its C-terminal in the interaction with the histone H3 tail. Indeed, without the ankyrin domains, RomA loses its ability to act as histone methyltransferase. These results discover the molecular mechanisms by which a bacterial histone methyltransferase that is conserved in L. pneumophila strains acts to modify chromatin.

Disparate Impact: How Does Social Deprivation Affect Patient-reported Outcomes After ACL Reconstruction in Children and Adolescents?

BACKGROUND: Research has indicated that lower socioeconomic status is associated with delays in the treatment of anterior cruciate ligament (ACL) injuries; however, there is a paucity of literature evaluating its association with patient-reported outcomes (PROs). Using the Area Deprivation Index (ADI), a validated proxy for socioeconomic status, the study aimed to determine how relative socioeconomic disadvantage is related to PROs after primary ACL reconstruction (ACLR) in pediatric patients. METHODS: This retrospective cohort study included all patients 18 years old or above who underwent primary ACLR at an academic institution between 2018 and 2021. Exclusion criteria included multiligament injury, congenital ACL absence, and absent outcomes data. The minimum follow-up was 6 months. A Patient-reported Outcomes Measurement Information System (PROMIS) 50 Pediatric self-report questionnaire was completed at postoperative visits, and domain scores for pain, physical function/mobility, fatigue, anxiety, depression, and peer relationships were generated. The National ADI percentile was calculated using the patients' addresses. Patients were divided into quartiles (low, moderate, moderate-severe, and severe ADI), and comparative analyses were performed to determine the relationship between ADI and PROMIS. RESULTS: A total of 413 patients were identified, including 49% (n=207), 33% (n=139), 11% (n=48), and 7% (n=30) from the low, moderate, moderate-severe, and severe deprivation areas, respectively. As compared with those in the low-deprivation quartile, patients in the severe deprivation quartile had delayed time to the first clinic visit (11 vs. 16.5 d, P=0.044) and surgery (51 vs. 80 d, P=0.004). There were no differences in the number of additional procedures required at index surgery. All quartiles had progressive improvements in physical function/mobility and pain scores throughout recovery, but at 9 months, there was significantly more pain in the severe deprivation cohort, despite no difference in self-reported physical function and mobility. Those with severe socioeconomic disadvantage had worse psychosocial outcomes, including significantly increased depression, fatigue, and anxiety and decreased peer relationship scores. CONCLUSIONS: Although there were no differences in preoperative PROMIS scores, pediatric patients living in areas with higher levels of socioeconomic deprivation/disadvantage had worse psychosocial PROs after ACLR. LEVEL OF EVIDENCE: Level III-retrospective comparative study.

An original potentiating mechanism revealed by the cryo-EM structures of the human α7 nicotinic receptor in complex with nanobodies.

The human α7 nicotinic receptor is a pentameric channel mediating cellular and neuronal communication. It has attracted considerable interest in designing ligands for the treatment of neurological and psychiatric disorders. To develop a novel class of α7 ligands, we recently generated two nanobodies named E3 and C4, acting as positive allosteric modulator and silent allosteric ligand, respectively. Here, we solved the cryo-electron microscopy structures of the nanobody-receptor complexes. E3 and C4 bind to a common epitope involving two subunits at the apex of the receptor. They form by themselves a symmetric pentameric assembly that extends the extracellular domain. Unlike C4, the binding of E3 drives an agonist-bound conformation of the extracellular domain in the absence of an orthosteric agonist, and mutational analysis shows a key contribution of an N-linked sugar moiety in mediating E3 potentiation. The nanobody E3, by remotely controlling the global allosteric conformation of the receptor, implements an original mechanism of regulation that opens new avenues for drug design.

Immunogenicity of a Plasmodium vivax vaccine based on the duffy binding protein formulated using adjuvants compatible for use in humans.

The invasion of reticulocytes by Plasmodium vivax merozoites is dependent on the interaction of the Plasmodium vivax Duffy Binding Protein (PvDBP) with the Duffy antigen receptor for chemokines (DARC). The N-terminal cysteine-rich region II of PvDBP (PvDBPII), which binds DARC, is a leading P. vivax malaria vaccine candidate. Here, we have evaluated the immunogenicity of recombinant PvDBPII formulated with the adjuvants Matrix-M and GLA-SE in mice. Analysis of the antibody responses revealed comparable ELISA recognition titres as well as similar recognition of native PvDBP in P. vivax schizonts by immunofluorescence assay. Moreover, antibodies elicited by the two adjuvant formulations had similar functional properties such as avidity, isotype profile and inhibition of PvDBPII-DARC binding. Furthermore, the anti-PvDBPII antibodies were able to block the interaction of DARC with the homologous PvDBPII SalI allele as well as the heterologous PvDBPII PvW1 allele from a Thai clinical isolate that is used for controlled human malaria infections (CHMI). The cross-reactivity of these antibodies with PvW1 suggest that immunization with the PvDBPII SalI strain should neutralize reticulocyte invasion by the challenge P. vivax strain PvW1.

Raynals, an online tool for the analysis of dynamic light scattering.

Dynamic light scattering (DLS) is routinely employed to assess the homogeneity and size-distribution profile of samples containing microscopic particles in suspension or solubilized polymers. In this work, Raynals, user-friendly software for the analysis of single-angle DLS data that uses the Tikhonov-Phillips regularization, is introduced. Its performance is evaluated on simulated and experimental data generated by different DLS instruments for several proteins and gold nanoparticles. DLS data can easily be misinterpreted and the simulation tools available in Raynals allow the limitations of the measurement and its resolution to be understood. It was designed as a tool to address the quality control of biological samples during sample preparation and optimization and it helps in the detection of aggregates, showing the influence of large particles. Lastly, Raynals provides flexibility in the way that the data are presented, allows the export of publication-quality figures, is free for academic use and can be accessed online on the eSPC data-analysis platform at https://spc.embl-hamburg.de/.

The cell wall lipoprotein CD1687 acts as a DNA binding protein during deoxycholate-induced biofilm formation in Clostridioides difficile.

The ability of bacterial pathogens to establish recurrent and persistent infections is frequently associated with their ability to form biofilms. Clostridioides difficile infections have a high rate of recurrence and relapses and it is hypothesized that biofilms are involved in its pathogenicity and persistence. Biofilm formation by C. difficile is still poorly understood. It has been shown that specific molecules such as deoxycholate (DCA) or metronidazole induce biofilm formation, but the mechanisms involved remain elusive. In this study, we describe the role of the C. difficile lipoprotein CD1687 during DCA-induced biofilm formation. We showed that the expression of CD1687, which is part of an operon within the CD1685-CD1689 gene cluster, is controlled by multiple transcription starting sites and some are induced in response to DCA. Only CD1687 is required for biofilm formation and the overexpression of CD1687 is sufficient to induce biofilm formation. Using RNAseq analysis, we showed that CD1687 affects the expression of transporters and metabolic pathways and we identified several potential binding partners by pull-down assay, including transport-associated extracellular proteins. We then demonstrated that CD1687 is surface exposed in C. difficile, and that this localization is required for DCA-induced biofilm formation. Given this localization and the fact that C. difficile forms eDNA-rich biofilms, we confirmed that CD1687 binds DNA in a non-specific manner. We thus hypothesize that CD1687 is a component of the downstream response to DCA leading to biofilm formation by promoting interaction between the cells and the biofilm matrix by binding eDNA.

The Epidemiology of Pediatric Basketball Injuries Presenting to US Emergency Departments: 2011-2020.

OBJECTIVES: The purpose of this study is to describe the national epidemiology of basketball-related injuries in children and adolescents presenting to US emergency departments (EDs) from 2011 to 2020 and to quantify the effect of the COVID-19 pandemic. METHODS: The National Electronic Injury Surveillance System database was queried for cases of injury in persons aged 0 to 19 years related to product code 1205 (basketball and related equipment) presenting from January 1, 2011 to December 31, 2020. National injury estimates were calculated using National Electronic Injury Surveillance System-recommended weights and strata. The US Census data were used to determine the incidence of injury by age group and by sex. To quantify the effect of COVID-19, an interrupted time series analysis was performed using March 1, 2020 as the interrupting time point. The pre-COVID-19 trend was used to estimate the difference in injuries attributable to the COVID-19 pandemic. RESULTS: From 2011 to 2020, an estimated 3,210,953 (95% confidence interval = 2,655,812-3,788,094) visits were made to US EDs for basketball-related injuries in those aged younger than 20 years, corresponding to a mean annual incidence of 391 injuries per 100,000 population. The mean age of injury was 14.4 years (95% confidence interval = 14.3-14.5). Boys were more often injured than girls (76% vs 24% of all injuries, respectively). The foot was the most injured body part, accounting for 24% of injuries. Strains or sprains were the most common injury type (38% of injuries). During the COVID-19 pandemic, there were 155,638 fewer injuries than were expected based on pre-COVID-19 trends. During COVID-19, there were no significant differences in the proportions of injury types, body parts involved, sex, or age. CONCLUSIONS: Basketball remains a frequent cause of injury, especially in adolescents. The COVID-19 pandemic profoundly reduced the frequency of basketball-related injuries, but did not affect the type and body location of injuries presenting to the ED.

The c-di-AMP-binding protein CbpB modulates the level of ppGpp alarmone in Streptococcus agalactiae.

Cyclic di-AMP is an essential signalling molecule in Gram-positive bacteria. This second messenger regulates the osmotic pressure of the cell by interacting directly with the regulatory domains, either RCK_C or CBS domains, of several potassium and osmolyte uptake membrane protein systems. Cyclic di-AMP also targets stand-alone CBS domain proteins such as DarB in Bacillus subtilis and CbpB in Listeria monocytogenes. We show here that the CbpB protein of Group B Streptococcus binds c-di-AMP with a very high affinity. Crystal structures of CbpB reveal the determinants of binding specificity and significant conformational changes occurring upon c-di-AMP binding. Deletion of the cbpB gene alters bacterial growth in low potassium conditions most likely due to a decrease in the amount of ppGpp caused by a loss of interaction between CbpB and Rel, the GTP/GDP pyrophosphokinase.

Why Don't Adolescents Wear Their Brace? A Prospective Study Investigating Psychosocial Characteristics That Predict Scoliosis Brace Wear.

BACKGROUND: Although bracing for adolescent idiopathic scoliosis can prevent curve progression and reduce the risk for future surgery, children frequently do not wear their braces as prescribed. The purpose of this study is to investigate how a broad array of psychosocial characteristics predict future compliance with scoliosis brace wear. METHODS: This was a single institution, prospective cohort study. All adolescents prescribed a first-time brace for adolescent idiopathic scoliosis were eligible. Patients and their parents completed a separate series of questionnaires that assessed baseline psychosocial characteristics across 6 domains: (1) brace-specific attitudes; (2) body image and self-esteem; (3) school performance and social relationships; (4) psychological health; (5) family functioning; and (6) demographics and scoliosis-specific details (242 total questions across 12 validated questionnaires). Objective brace compliance was collected using temperature-sensitive monitors. Defining compliance as percentage of brace prescription completed, comparative analyses were performed to identify baseline psychosocial characteristics that were associated with future wear. A composite measure (Bracing Fidelity Follow-Up Scale [BFFS]) of the 12 most predictive individual questions across all domains (both parent and adolescent) was constructed to help assess which adolescents were at highest risk of failure to wear their brace. Total BFFS score for each parent-adolescent dyad who completed all the included surveys was then determined by awarding one point for each factor that positively influenced future brace wear (maximum 12 points), and a correlation was calculated between total score and percent adherence to prescribed brace wear. RESULTS: A total of 41 patients were included. On average, patients with high self-esteem, above average peer relationships and poor brace-specific attitudes had lower brace compliance, although patients with increased loneliness and parental religiousness had higher compliance. Body image, socioeconomic status, family dynamics, and school performance had no significant relationship with brace use. Total score on the Bracing Fidelity Follow-Up Scale (BFFS) was significantly associated with improved brace wear (r=0.687, P <0.001). Those with a score of 6 or above (n=15/33 [45%], median compliance 96%) were more reliable users (15/15 with compliance >75%), and those with a score of 5 or less (n=18/33 [55%], median compliance 50%) had less consistent brace wear (9/18 with compliance <50%). CONCLUSION: This prospective study identifies numerous baseline psychosocial factors that are associated with future compliance with scoliosis brace wear. Although in need of further validation before widespread clinical application, the novel BFF scale offers a potential opportunity to partially discriminate between compliant and noncompliant scoliosis brace users such that supportive resources (eg, supportive counseling, peer-support groups, additional provider-based education, etc.) can be targeted to those patients most likely to benefit. LEVEL OF EVIDENCE: II.

Examining patient perspectives on sarcoma surveillance: The Sarcoma Surveillance Survey.

OBJECTIVES: The optimal frequency and modality of sarcoma surveillance imaging are uncertain, and current practices vary substantially. While efforts to develop evidence-based guidelines are ongoing, patient perspectives regarding surveillance imaging have not been reported. The primary goal of this study was to pilot the novel Sarcoma Surveillance Survey to assess patient concerns regarding sarcoma surveillance. METHODS: In this single-center, cross-sectional study, patients receiving surveillance imaging after surgical sarcoma treatment were administered the 10-item Sarcoma Surveillance Survey, the validated Appraisal Scale, measuring positive and negative emotional reactions to imaging, and the Patient-Reported Outcomes Measurement Information System (PROMIS) Anxiety Short Form 8a as a measure of anxiety. RESULTS: Patients expressed highest levels of concern about cost and radiation exposure associated with surveillance, and most (87.6%) did not express a preference for more or less frequent imaging. Younger patients and those living further away from the imaging center were more concerned about cost of surveillance. Female patients had higher levels of concern compared to males regarding radiation, IV contrast, and overall levels of concern about surveillance. Higher levels of anxiety were correlated with preference for more frequent imaging (rs = 0.274, p = 0.027) and higher overall level of concern about surveillance (rs = 0.259, p = 0.037). Higher negative appraisal scores were also correlated with higher overall concerns (rs = 0.323; p = 0.012). CONCLUSIONS: Patient perspectives should be considered when developing sarcoma surveillance strategies. Identifying patients with greater anxiety and concerns regarding imaging may create opportunities for improved surveillance practices as well as counseling and survivorship interventions.

Patient and Disease Related Risk Factors Associated With Return to Sport Rates After AVN Treatment.

Background: Avascular necrosis (AVN) is a rare albeit serious condition that has a high risk for long term morbidity given the risk of chronic pain and arthroplasty after diagnoses. The recent rise in sports participation in the pediatric population demonstrates the importance of evaluating functional limitations after AVN treatment. Return to sport (RTS) rates after treatment for AVN have not been evaluated in pediatric or adolescent populations.It is necessary to evaluate all joints impacted by AVN due to heterogenous nature of the disease and the variety of sports that could be impacted by disease specific activity restrictions. Thus, this present study aimed to characterize RTS rate after AVN treatment, determine if there was a difference in RTS rates after operative versus nonoperative management, and identify demographic and treatment factors associated with RTS rates. Methods: This retrospective cohort study evaluated patients ages eight to twenty years old who were treated for symptomatic AVN of any joint between January 2005 and August 2021. Patient records were reviewed for demographic, disease, and treatment variables. Standard descriptive statistics and bivariate analyses were performed to describe and compare groups who did and did not RTS. A generalized estimating model was used to determine variables that were associated with better RTS rates. Results: A total of 144 patients and 190 lesions were evaluated in the study, 60 patients (43%) were female with a mean age of 14.36+/-3.24 years. The overall RTS rate after AVN treatment was 67% (64/96). Roughly 8% of patients (5/64) were able to return to multiple sports, however of those that returned to sports, 6% (4/64) reported playing at a lower level of competition. There was not a significant difference between the RTS rate for those who underwent operative versus nonoperative management (70% versus 62%, p=0.38). Males were almost 2.5 times more likely to return to sport than females (OR: 2.46, p=0.018). Conclusion: The ability to return to sports after AVN treatment has largely remained unknown in the pediatric and adolescent populations. Our data suggests that a majority of patients are able to RTS in the short term follow up with males being twice as likely to RTS compared to females. Physicians should maintain awareness of the long-term morbidity of AVN and understand the unique patient and disease characteristics that optimize functional outcomes in this population. Level of Evidence: III.

Evolution and activation mechanism of the flavivirus class II membrane-fusion machinery.

The flavivirus envelope glycoproteins prM and E drive the assembly of icosahedral, spiky immature particles that bud across the membrane of the endoplasmic reticulum. Maturation into infectious virions in the trans-Golgi network involves an acid-pH-driven rearrangement into smooth particles made of (prM/E)2 dimers exposing a furin site for prM cleavage into "pr" and "M". Here we show that the prM "pr" moiety derives from an HSP40 cellular chaperonin. Furthermore, the X-ray structure of the tick-borne encephalitis virus (pr/E)2 dimer at acidic pH reveals the E 150-loop as a hinged-lid that opens at low pH to expose a positively-charged pr-binding pocket at the E dimer interface, inducing (prM/E)2 dimer formation to generate smooth particles in the Golgi. Furin cleavage is followed by lid-closure upon deprotonation in the neutral-pH extracellular environment, expelling pr while the 150-loop takes the relay in fusion loop protection, thus revealing the elusive flavivirus mechanism of fusion activation.

Patients With Metastatic Disease Are at Highest Risk for Anxiety and Depression in an Orthopedic Oncology Patient Population.

PURPOSE: Patients with cancer are at risk for anxiety and depression; however, the patterns and predictors of symptoms in an orthopedic oncology population have not been studied. METHODS: We retrospectively reviewed Patient-Reported Outcomes Measurement Information System scores of all adult patients who underwent palliative surgery for metastatic cancer, resection of a sarcoma, or nononcologic total joint arthroplasty at a single institution from 2015 to 2020. Backward stepwise linear regression was used to determine risk factors for perioperative anxiety and depression. RESULTS: Postoperative anxiety and depression were more prevalent in patients with metastatic disease than localized cancer or nononcologic conditions (P < .001 and P < .001, respectively). Worse preoperative pain and function were associated with higher preoperative anxiety (ß = .321, P = .001; ß = -.236, P = .012, respectively) and depression (ß = .245, P = .009; ß = -.279, P = .003, respectively). Worse preoperative anxiety, preoperative depression, and postoperative pain were associated with higher postoperative anxiety (ß = .204, P = .012; ß = .260, P = .001; ß = .447, P < .001, respectively). Worse preoperative depression and postoperative pain also predicted higher postoperative depression (ß = .542, P < .001; ß = .325, P < .001, respectively). CONCLUSION: Anxiety and depression were most prevalent in patients with metastatic disease. Compared with total joint arthroplasty patients, patients with cancer less frequently experienced postoperative improvements in anxiety and depression. Worse preoperative pain and function were independently associated with greater preoperative anxiety and depression. Providers should maintain awareness of the relationship between mental and physical health to optimize outcomes.

High-affinity autoreactive plasma cells disseminate through multiple organs in patients with immune thrombocytopenic purpura.

The major therapeutic goal for immune thrombocytopenic purpura (ITP) is to restore normal platelet counts using drugs to promote platelet production or by interfering with mechanisms responsible for platelet destruction. Eighty percent of patients with ITP possess anti-integrin αIIbß3 IgG autoantibodies that cause platelet opsonization and phagocytosis. The spleen is considered the primary site of autoantibody production by autoreactive B cells and platelet destruction. The immediate failure in approximately 50% of patients to recover a normal platelet count after anti-CD20 rituximab-mediated B cell depletion and splenectomy suggests that autoreactive, rituximab-resistant, IgG-secreting B cells (IgG-SCs) reside in other anatomical compartments. We analyzed more than 3,300 single IgG-SCs from spleen, bone marrow, and/or blood of 27 patients with ITP, revealing high interindividual variability in affinity for αIIbß3, with variations over 3 logs. IgG-SC dissemination and range of affinities were, however, similar for each patient. Longitudinal analysis of autoreactive IgG-SCs upon treatment with the anti-CD38 mAb daratumumab demonstrated variable outcomes, from complete remission to failure with persistence of high-affinity anti-αIIbß3 IgG-SCs in the bone marrow. This study demonstrates the existence and dissemination of high-affinity autoreactive plasma cells in multiple anatomical compartments of patients with ITP that may cause the failure of current therapies.