Clinical and Microbial Determinants of Upper Respiratory Colonization with Streptococcus pneumoniae and Native Microbiota in People with HIV-1 and Control Adults.

BACKGROUND: The substantial risk for respiratory and invasive infections with Streptococcus pneumoniae (Spn) among people with HIV-1 (PWH) begins with asymptomatic colonization. The frequency of Spn colonization among U.S. adults with and without HIV-1 infection is not well-characterized in the conjugate vaccine era. METHODS: We determined Spn colonization frequency by culture and specific lytA gene QPCR and microbiota profile by 16S rRNA gene sequencing in nasopharyngeal (NP) and oropharyngeal (OP) DNA from 138 PWH and 93 control adults and associated clinical characteristics. RESULTS: The frequencies of Spn colonization among PWH and controls did not differ (11.6% vs 8.6%, respectively; p=0.46) using combined results of culture and PCR, independent of vaccination or behavioral risks. PWH showed altered microbiota composition (i.e., beta-diversity. NP: p=0.0028, OP: p=0.0098), decreased alpha-diversity (NP: p=0.024, OP: p=0.0045), and differences in the relative abundance of multiple bacterial taxa. Spn colonization was associated with altered beta-diversity in the NP (p=0.011), but not OP (p=0.21). CONCLUSIONS: Despite widespread conjugate vaccine and antiretroviral use, frequencies of Spn colonization among PWH and controls are currently consistent with those reported in the pre-conjugate era. The persistently increased risk of pneumococcal disease despite ART may relate to behavioral and immunologic variables other than colonization.

Altered Immunoglobulin Repertoire and Decreased IgA Somatic Hypermutation in the Gut during Chronic HIV-1 Infection.

Humoral immune perturbations contribute to pathogenic outcomes in persons with HIV-1 infection (PWH). Gut barrier dysfunction in PWH is associated with microbial translocation and alterations in microbial communities (dysbiosis), and IgA, the most abundant immunoglobulin (Ig) isotype in the gut, is involved in gut homeostasis by interacting with the microbiome. We determined the impact of HIV-1 infection on the antibody repertoire in the gastrointestinal tract by comparing Ig gene utilization and somatic hypermutation (SHM) in colon biopsies from PWH (n = 19) versus age and sex-matched controls (n = 13). We correlated these Ig parameters with clinical, immunological, microbiome and virological data. Gene signatures of enhanced B cell activation were accompanied by skewed frequencies of multiple Ig Variable genes in PWH. PWH showed decreased frequencies of SHM in IgA and possibly IgG, with a substantial loss of highly mutated IgA sequences. The decline in IgA SHM in PWH correlated with gut CD4+ T cell loss and inversely correlated with mucosal inflammation and microbial translocation. Diminished gut IgA SHM in PWH was driven by transversion mutations at A or T deoxynucleotides, suggesting a defect not at the AID/APOBEC3 deamination step but at later stages of IgA SHM. These results expand our understanding of humoral immune perturbations in PWH that could have important implications in understanding mucosal immune defects in individuals with chronic HIV-1 infection. IMPORTANCE The gut is a major site of early HIV-1 replication and pathogenesis. Extensive CD4+ T cell depletion in this compartment results in a compromised epithelial barrier that facilitates the translocation of microbes into the underlying lamina propria and systemic circulation, resulting in chronic immune activation. To date, the consequences of microbial translocation on the mucosal humoral immune response (or vice versa) remains poorly integrated into the panoply of mucosal immune defects in PWH. We utilized next-generation sequencing approaches to profile the Ab repertoire and ascertain frequencies of somatic hypermutation in colon biopsies from antiretroviral therapy-naive PWH versus controls. Our findings identify perturbations in the Ab repertoire of PWH that could contribute to development or maintenance of dysbiosis. Moreover, IgA mutations significantly decreased in PWH and this was associated with adverse clinical outcomes. These data may provide insight into the mechanisms underlying impaired Ab-dependent gut homeostasis during chronic HIV-1 infection.

Impact of HIV-1 Infection and Antigen Class on T Follicular Helper Cell Responses to Pneumococcal Polysaccharide-Protein Conjugate Vaccine-13.

Pneumococcal infections are common and serious complications of HIV-1 disease. Prevention has been compromised by the limited magnitude and quality of Ab responses to T cell-independent type 2 pneumococcal capsular polysaccharides (PPS). The pneumococcal polysaccharide-protein conjugate vaccine-13 (PCV-13) contains PPS conjugated to the T cell-dependent protein (diphtheria toxoid [DT] [CRM197]). We investigated the differential response to PPS and DT by human Ab-secreting B cells (ASC) after immunization with PCV-13 in newly diagnosed healthy HIV+ and control adults. The numbers of PPS-specific IgG ASC increased significantly and similarly in HIV+ and controls. However, DT-specific IgG ASC increased in controls but not HIV+ subjects. To determine the cellular basis of these disparate responses to DT and PPS, we characterized the frequency and activation of T follicular helper (Tfh) cells, the predominant T cell subset providing B cell help. Expression of inducible T cell costimulator (ICOS), which sustains Tfh function and phenotype, increased significantly among controls, when compared with the HIV+ group. Increases in ICOS+ Tfh correlated with changes in T-dependent, DT-specific IgG ASC in controls but not in HIV+ In contrast, ICOS expression did not correlate with T cell-independent type 2 PPS-specific ASC in either group. Of note, upon optimized ex vivo stimulation, CD4 T cells from HIV+ subjects differentiated into Tfh cells and formed synapses with Raji B cells at frequencies similar to that of controls. In summary, PCV-13-induced increase in ICOS expression on Tfh was associated with responses to DT, which was compromised in recently diagnosed healthy HIV+ adults and can be restored ex vivo by providing effective Tfh-differentiating signals.

Designing and implementing methodology for double-blind, placebo-controlled clinical trials using blood products within the Department of Veterans Affairs.

BACKGROUND: Success in conducting clinical trials during the coronavirus disease of 2019 pandemic requires the ability to innovate and adapt. There are well-established procedures for the blinding of investigational agents, especially medications, in placebo-controlled randomized clinical trials within the Veterans Health Administration. However, these procedures, managed by research pharmacists, may not apply to investigational agents that are not exclusively managed by pharmacy, such as blood products, including coronavirus disease of 2019 convalescent plasma (plasma). In the absence of established blinding procedures, such studies require special design considerations to minimize uncertainty or bias. METHODS: We describe the processes and procedures developed for blinding of plasma in "Veterans Affairs CoronavirUs Research and Efficacy Studies-1" as a prototypical study using this class of investigational therapeutic agents. Veterans Affairs CoronavirUs Research and Efficacy Studies-1 is an ongoing multicenter randomized clinical trial testing the efficacy of plasma added to conventional therapy for severe acute respiratory syndrome coronavirus-2 infection. RESULTS: We report the design of procedures to supply investigational blood products or 0.9% normal saline (saline) control while ensuring the integrity of the blind. Key aspects include workflow considerations, physical blinding strategies, and methods for engaging stakeholders. These procedures leverage the well-established Veterans Affairs research pharmacist's research infrastructure, and Blood Bank Services, which is responsible for blood-based investigational products. CONCLUSION: By describing the methods used to deliver blood products in a blinded manner in Veterans Affairs CoronavirUs Research and Efficacy Studies-1, we strive both to educate and to increase awareness to improve the implementation of these biological therapeutics for future, high-quality research studies.

The Impact of Moderate or High-Intensity Combined Exercise on Systemic Inflammation Among Older Persons With and Without HIV.

BACKGROUND: We investigated whether higher-intensity exercise provided greater decrease in markers of inflammation, and whether responses differed by HIV serostatus. METHODS: People with HIV (PWH; n = 32) and controls (n = 37) aged 50-75 years completed 12 weeks moderate-intensity exercise, then were randomized to moderate- or high-intensity exercise for 12 additional weeks (n = 27 and 29, respectively). Inflammation biomarkers were measured at 0, 12, 24 weeks. Mixed and multiple regression models were adjusted for baseline inflammation, age, and body mass index. RESULTS: Baseline tumor necrosis factor-α (TNF-α), soluble TNF receptor 2 (sTNFR2), and soluble CD14 (sCD14) were significantly higher among PWH than controls (P < .04). From week 0-12, changes in interleukin-6 (IL-6), TNF-α, and sTNFR1 were not significantly different by HIV serostatus. We found no significant interaction between HIV serostatus/exercise intensity on week 12-24 changes in IL-6, TNF-α, and sTNFR1. Among high-intensity exercisers, PWH and controls had significant increases in sCD14 (P ≤ .003), controls significant increases in IL-10 (P = .01), and PWH nonsignificant decrease in highly sensitive C-reactive protein (P = .07). Other markers were not significantly different by serostatus or intensity. CONCLUSIONS: Moderate and high-intensity exercise elicited similar effects on inflammation among PWH and controls, with additional beneficial effects seen among high-intensity exercisers. Increase in sCD14 and attenuated IL-10 increase (PWH only) merit further study. CLINICAL TRIALS REGISTRATION: NCT02404792.

B Cell Compartmentalization in Blood and Cerebrospinal Fluid of HIV-Infected Ugandans with Cryptococcal Meningitis.

Activated B cells modulate infection by differentiating into pathogen-specific antibody-producing effector plasmablasts/plasma cells, memory cells, and immune regulatory B cells. In this context, the B cell phenotypes that infiltrate the central nervous system during human immunodeficiency virus (HIV) and cryptococcal meningitis coinfection are ill defined. We characterized clinical parameters, mortality, and B cell phenotypes in blood and cerebrospinal fluid (CSF) by flow cytometry in HIV-infected adults with cryptococcal (n = 31) and noncryptococcal (n = 12) meningitis and in heathy control subjects with neither infection (n = 10). Activation of circulating B cells (CD21low) was significantly higher in the blood of subjects with HIV infection than in that of healthy controls and greater yet in matched CSF B cells (P < 0.001). Among B cell subsets, elevated frequencies of memory and plasmablasts/plasma cells most clearly distinguished the CSF from blood compartments. With cryptococcal meningitis, lower frequencies of expression of the regulatory protein programmed death-1 (PD-1) on plasmablasts/plasma cells in blood (median, 7%) at presentation were associated with significantly decreased 28-day survival (29% [4/14 subjects]), whereas higher PD-1 expression (median, 46%) characterized subjects with higher survival (88% [14/16 subjects]). With HIV infection, B cell differentiation and regulatory markers are discrete elements of the circulating and CSF compartments with clinical implications for cryptococcal disease outcome, potentially due to their effects on the fungus and other local immune cells.

Ontogeny of CD4+ T Lymphocytes With Phenotypic Susceptibility to HIV-1 During Exclusive and Nonexclusive Breastfeeding in HIV-1-Exposed Ugandan Infants.

Background: Among infants exposed to human immunodeficiency virus (HIV) type 1, mixed breastfeeding is associated with higher postnatal HIV-1 transmission than exclusive breastfeeding, but the mechanisms of this differential risk are uncertain. Methods: HIV-1-exposed Ugandan infants were prospectively assessed during the first year of life for feeding practices and T-cell maturation, intestinal homing (ß7hi), activation, and HIV-1 coreceptor (CCR5) expression in peripheral blood. Infants receiving only breast milk and those with introduction of other foods before 6 months were categorized as exclusive and nonexclusive, respectively. Results: Among CD4+ and CD8+ T cells, the expression of memory, activation, and CCR5 markers increased rapidly from birth to week 2, peaking at week 6, whereas cells expressing the intestinal homing marker increased steadily in the central memory (CM) and effector memory T cells over 48 weeks. At 24 weeks, when feeding practices had diverged, nonexclusively breastfed infants showed increased frequencies and absolute counts of ß7hi CM CD4+ and CD8+ T cells, including the HIV-1-targeted cells with CD4+ß7hi/CCR5+ coexpression, as well as increased activation. Conclusions: The T-cell phenotype associated with susceptibility to HIV-1 infection (CCR5+, gut-homing, CM CD4+ T cells) was preferentially expressed in nonexclusively breastfed infants, a group of infants at increased risk for HIV-1 acquisition.

Timing of antiretroviral therapy after diagnosis of cryptococcal meningitis.

BACKGROUND: Cryptococcal meningitis accounts for 20 to 25% of acquired immunodeficiency syndrome-related deaths in Africa. Antiretroviral therapy (ART) is essential for survival; however, the question of when ART should be initiated after diagnosis of cryptococcal meningitis remains unanswered. METHODS: We assessed survival at 26 weeks among 177 human immunodeficiency virus-infected adults in Uganda and South Africa who had cryptococcal meningitis and had not previously received ART. We randomly assigned study participants to undergo either earlier ART initiation (1 to 2 weeks after diagnosis) or deferred ART initiation (5 weeks after diagnosis). Participants received amphotericin B (0.7 to 1.0 mg per kilogram of body weight per day) and fluconazole (800 mg per day) for 14 days, followed by consolidation therapy with fluconazole. RESULTS: The 26-week mortality with earlier ART initiation was significantly higher than with deferred ART initiation (45% [40 of 88 patients] vs. 30% [27 of 89 patients]; hazard ratio for death, 1.73; 95% confidence interval [CI], 1.06 to 2.82; P=0.03). The excess deaths associated with earlier ART initiation occurred 2 to 5 weeks after diagnosis (P=0.007 for the comparison between groups); mortality was similar in the two groups thereafter. Among patients with few white cells in their cerebrospinal fluid (<5 per cubic millimeter) at randomization, mortality was particularly elevated with earlier ART as compared with deferred ART (hazard ratio, 3.87; 95% CI, 1.41 to 10.58; P=0.008). The incidence of recognized cryptococcal immune reconstitution inflammatory syndrome did not differ significantly between the earlier-ART group and the deferred-ART group (20% and 13%, respectively; P=0.32). All other clinical, immunologic, virologic, and microbiologic outcomes, as well as adverse events, were similar between the groups. CONCLUSIONS: Deferring ART for 5 weeks after the diagnosis of cryptococcal meningitis was associated with significantly improved survival, as compared with initiating ART at 1 to 2 weeks, especially among patients with a paucity of white cells in cerebrospinal fluid. (Funded by the National Institute of Allergy and Infectious Diseases and others; COAT ClinicalTrials.gov number, NCT01075152.).

Expression of immunoglobulin D is increased in chronic rhinosinusitis.

BACKGROUND: Immunoglobulin (Ig) D is largely localized to the upper airway and reacts with colonizing respiratory pathogens. OBJECTIVE: To determine whether chronic rhinosinusitis (CRS) is associated with increased IgD expression. METHODS: We performed immunofluorescent staining for cytoplasmic IgD, IgA, IgM, and surface plasma cell marker CD138 (syndecan-1) in sinus tissue of patients with CRS with and without nasal polyps (CRSwNP and CRSsNP, respectively) and control subjects without CRS (n = 6 each). Sinonasal mucus antibody levels of patients with CRSwNP or CRSsNP and control subjects were measured by enzyme-linked immunosorbent assay (n = 13, 11, and 9 subjects, respectively). Cells per square millimeter and antibody levels were compared by analysis of variance. Histopathology was performed with sinus tissue from subjects in the 3 groups (n = 6, 8, and 13 subjects respectively). RESULTS: Cells expressing cytoplasmic IgD exceeded those with cytoplasmic IgA and IgM and represented most CD138+ plasma cells in the lamina propria. The frequencies of IgD+ plasma cells were significantly higher in patients with CRSsNP and CRSwNP compared with control subjects (P < .01). Only patients with CRSwNP showed increased frequencies of IgM and IgA plasma cells (P < .01). In contrast to high plasma cell frequencies in tissues, the levels of secreted IgD were lower than those of IgA, IgM, and IgG but were highest in the CRSwNP group compared with the other groups (P < .05). CONCLUSION: IgD plasma cells are prominent in sinus tissues and are increased in CRS. That IgD protein also shows the lowest concentration of antibodies in secretions suggests that its activity might be targeted to the tissue rather than secretions.

The immunopathogenesis of cryptococcal immune reconstitution inflammatory syndrome: understanding a conundrum.

PURPOSE OF REVIEW: Cryptococcal meningitis causes significant mortality among HIV-infected patients, despite antifungal therapy and use of antiretroviral therapy (ART). In patients with cryptococcal meningitis, ART is often complicated by immune reconstitution inflammatory syndrome (IRIS), manifesting as unmasking of previously unrecognized subclinical infection (unmasking CM-IRIS) or paradoxical worsening of symptoms in the central nervous system after prior improvement with antifungal therapy (paradoxical CM-IRIS). We review our current understanding of the pathogenesis of this phenomenon, focusing on unifying innate and adaptive immune mechanisms leading to the development of this often fatal syndrome. RECENT FINDINGS: We propose that HIV-associated CD4 T-cell depletion, chemokine-driven trafficking of monocytes into cerebrospinal fluid in response to cryptococcal meningitis, and poor localized innate cytokine responses lead to inadequate cryptococcal killing and clearance of the fungus. Subsequent ART-associated recovery of T-cell signaling and restored cytokine responses, characterized by IFN-γ production, triggers an inflammatory response. The inflammatory response triggered by ART is dysregulated because of impaired homeostatic and regulatory mechanisms, culminating in the development of CM-IRIS. SUMMARY: Despite our incomplete understanding of the immunopathogenesis of CM-IRIS, emerging data exploring innate and adaptive immune responses could be exploited to predict, prevent and manage CM-IRIS and associated morbid consequences.

The relationship of circulating proteins in early pregnancy with preterm birth.

BACKGROUND: Preterm birth (PTB) (< 37 completed weeks' gestation) is a pathological outcome of pregnancy and a major global health problem. Babies born preterm have an elevated risk for long-term adverse medical and neurodevelopmental sequelae. Substantial evidence implicates intrauterine infection and/or inflammation in PTB. However, these are often relatively late findings in the process, when PTB is inevitable. Identification of earlier markers of PTB may make successful intervention possible. Although select proteins, notably those related to the inflammatory pathways, have been associated with PTB, there has been a lack of research into the role of other protein pathways in the development of PTB. The purpose of this study was to investigate, using a previously described biomarker discovery approach, a subset of circulating proteins and their association with PTB focusing on samples from early pregnancy. OBJECTIVES: The objectives of the study were as follows: (1) to perform a large-scale biomarker discovery, utilizing an innovative platform to identify proteins associated with preterm birth in plasma taken between 10 and 15 weeks' gestation and, (2) to determine which protein pathways are most strongly associated with preterm birth. To address these aims, we measured 1129 proteins in a plasma sample from early pregnancy using a multiplexed aptamer-based proteomic technology developed in Colorado by SomaLogic. STUDY DESIGN: Using a nested case-control approach, we measured proteins at a single time point in early pregnancy in 41 women who subsequently delivered preterm and 88 women who had term uncomplicated deliveries. We measured 1129 proteins using a multiplexed aptamer-based proteomic technology developed by SomaLogic. Logistic regressions and random forests were used to compare protein levels. RESULTS: The complement factors B and H and the coagulation factors IX and IX ab were the highest-ranking proteins distinguishing cases of preterm birth from term controls. The top 3 pathways associated with preterm birth were the complement cascade, the immune system, and the clotting cascade. CONCLUSION: Using a discovery approach, these data provide further confirmation that there is an association of immune- and coagulation-related events in early pregnancy with preterm birth. Thus, plasma protein profiles at 10-15 weeks of gestation are related to the development of preterm birth later in pregnancy.

Mouse marginal zone B cells harbor specificities similar to human broadly neutralizing HIV antibodies.

A series of potent, broadly neutralizing HIV antibodies have been isolated from B cells of HIV-infected individuals. VRC01 represents a subset of these antibodies that mediate neutralization with a restricted set of IGHV genes. The memory B cells expressing these antibodies were isolated years after infection; thus, the B-cell subpopulation from which they originated and the extent of participation in the initial HIV antibody response, if any, are unclear. Here we evaluated the frequency of anti-gp120 B cells in follicular (FO) and marginal zone (MZ) B-cell compartments of naïve WT mice and comparable human populations in uninfected individuals. We found that in non-HIV-exposed humans and mice, the majority of gp120-reactive B cells are of naïve and FO phenotype, respectively. Murine FO B cells express a diverse antibody repertoire to recognize gp120. In contrast, mouse MZ B cells recognize gp120 less frequently but preferentially use IGHV1-53 to encode gp120-specific antibodies. Notably, IGHV1-53 shows high identity to human IGHV1-2*02, which has been repeatedly found to encode broadly neutralizing mutated HIV antibodies, such as VRC01. Finally, we show that human MZ-like B cells express IGHV1-2*02, and that IGHV1-53 expression is enriched in mouse MZ B cells. These data suggest that efforts toward developing an HIV vaccine might consider eliciting protective HIV antibody responses selectively from alternative B-cell populations harboring IGHV gene segments capable of producing protective antibodies.

Cellular immune activation in cerebrospinal fluid from ugandans with cryptococcal meningitis and immune reconstitution inflammatory syndrome.

BACKGROUND: Human immunodeficiency virus (HIV)-associated cryptococcal meningitis (CM) is characterized by high fungal burden and limited leukocyte trafficking to cerebrospinal fluid (CSF). The immunopathogenesis of CM immune reconstitution inflammatory syndrome (IRIS) after initiation of antiretroviral therapy at the site of infection is poorly understood. METHODS: We characterized the lineage and activation status of mononuclear cells in blood and CSF of HIV-infected patients with noncryptococcal meningitis (NCM) (n = 10), those with CM at day 0 (n = 40) or day 14 (n = 21) of antifungal therapy, and those with CM-IRIS (n = 10). RESULTS: At diagnosis, highly activated CD8(+) T cells predominated in CSF in both CM and NCM. CM-IRIS was associated with an increasing frequency of CSF CD4(+) T cells (increased from 2.2% to 23%; P = .06), a shift in monocyte phenotype from classic to an intermediate/proinflammatory, and increased programmed death ligand 1 expression on natural killer cells (increased from 11.9% to 61.6%, P = .03). CSF cellular responses were distinct from responses in peripheral blood. CONCLUSIONS: After CM, T cells in CSF tend to evolve with the development of IRIS, with increasing proportions of activated CD4(+) T cells, migration of intermediate monocytes to the CSF, and declining fungal burden. These changes provide insight into IRIS pathogenesis and could be exploited to more effectively treat CM and prevent CM-IRIS.

Impact of Cerebrospinal Fluid Leukocyte Infiltration and Neuroimmmune Mediators on Survival with HIV-Associated Cryptococcal Meningitis.

Introduction: Cryptococcal meningitis remains a prominent cause of death in persons with advanced HIV disease. CSF leukocyte infiltration predicts survival at 18 weeks; however, how CSF immune response relates to CSF leukocyte infiltration is unknown. Methods: We enrolled 401 adults with HIV-associated cryptococcal meningitis in Uganda who received amphotericin and fluconazole induction therapy. We assessed the association of CSF leukocytes, chemokine, and cytokine responses with 18-week survival. Results: Participants with CSF leukocytes ≥50/µL, had higher probability 68% (52/77) of 18-week survival compared with 52% (151/292) 18-week survival in those with ≤50 cells/µL (Hazard Ratio=1.63, 95% confidence intervals 1.14-2.23; p=0.008). Survival was also associated with higher expression of T helper (Th)-1, Th17 cytokines, and immune regulatory elements. CSF levels of Programmed Death-1 Ligand, CXCL10, and Interleukin (IL)-2 independently predicted survival. In multivariate analysis, CSF leukocytes were inversely associated with CSF fungal burden and positively associated with CSF protein, interferon-gamma (IFN-γ), IL-17A, tumor necrosis factor (TNF)-α, and peripheral blood CD4+ and CD8+ T cells expression. Conclusion: 18-week survival after diagnosis of cryptococcal meningitis was associated with higher CSF leukocytes at baseline with greater T helper 1 (IFN-γ, IL-2 and TNF-α cytokines), T helper 17 (IL-17A cytokine) and CXCR3+ T cell (CXCL10 chemokine) responses. These results highlight the interdependent contribution of soluble and cellular immune responses in predicting survival with HIV-associated cryptococcal meningitis.

Lactation and neonatal nutrition: defining and refining the critical questions.

This paper resulted from a conference entitled "Lactation and Milk: Defining and refining the critical questions" held at the University of Colorado School of Medicine from January 18-20, 2012. The mission of the conference was to identify unresolved questions and set future goals for research into human milk composition, mammary development and lactation. We first outline the unanswered questions regarding the composition of human milk (Section I) and the mechanisms by which milk components affect neonatal development, growth and health and recommend models for future research. Emerging questions about how milk components affect cognitive development and behavioral phenotype of the offspring are presented in Section II. In Section III we outline the important unanswered questions about regulation of mammary gland development, the heritability of defects, the effects of maternal nutrition, disease, metabolic status, and therapeutic drugs upon the subsequent lactation. Questions surrounding breastfeeding practice are also highlighted. In Section IV we describe the specific nutritional challenges faced by three different populations, namely preterm infants, infants born to obese mothers who may or may not have gestational diabetes, and infants born to undernourished mothers. The recognition that multidisciplinary training is critical to advancing the field led us to formulate specific training recommendations in Section V. Our recommendations for research emphasis are summarized in Section VI. In sum, we present a roadmap for multidisciplinary research into all aspects of human lactation, milk and its role in infant nutrition for the next decade and beyond.

Crohn's patients and healthy infants share immunodominant B cell response to commensal flagellin peptide epitopes.

About half of patients with Crohn's disease (CD) develop selective serum IgG response to flagellin proteins of the Lachnospiraceae family. Here, we identified a dominant B cell peptide epitope in CD, locating in the highly conserved "hinge region" between the D0 and D1 domains at the amino-terminus of Lachnospiraceae flagellins. Serum IgG reactive to this epitope is present at an elevated level in adult CD patients and in pediatric CD patients at diagnosis. Most importantly, high levels of serum IgG to the hinge epitope were found in most infants from 3 different geographic regions (Uganda, Sweden, and the USA) at one year of age. This vigorous homeostatic response decrements with age as it is not present in healthy adults. These data identify a distinct subset of CD patients, united by a shared reactivity to this dominant flagellin epitope that may represent failure of a homeostatic response beginning in infancy.

Divergent Neuroimmune Signatures in the Cerebrospinal Fluid Predict Differential Gender-Specific Survival Among Patients With HIV-Associated Cryptococcal Meningitis.

Survival among people with HIV-associated cryptococcal meningitis (CM) remains low, exceptionally among women with the increased threat of death on current optimal use of antifungal drugs. Cryptococcus dissemination into the central nervous system (CNS) prompts a neuroimmune reaction to activate pathogen concomitant factors. However, no consistent diagnostic or prognostic immune-mediated signature is reported to underpin the risk of death or mechanism to improve treatment or survival. We theorized that the distinct neuroimmune cytokine or chemokine signatures in the cerebrospinal fluid (CSF), distinguish survivors from people who died on antifungal treatment, who may benefit from tailored therapy. We considered the baseline clinical disease features, cryptococcal microbiologic factors, and CSF neuroimmune modulated signatures among 419 consenting adults by gender (biological sex assigned at birth) (168 females and 251 males) by 18 weeks of survival on antifungal management. Survival at 18 weeks was inferior among females than males (47% vs. 59%; hazard ratio HR=1.4, 95% CI: 1.0 to 1.9, and p=0.023). Unsupervised principal component analysis (PCA) demonstrated the divergent neuroimmune signatures by gender, survival, and intragender-specific survival. Overall, females displayed lower levels of PD-L1, IL-1RA, and IL-15 than males (all p≤0.028). Female survivors compared with those who died, expressed significant fold elevations in levels of CSF (CCL11 - myeloid and CXCL10 - lymphoid chemokine (in both p=0.001), and CSF Th1, Th2, and Th17 cytokines. In contrast, male survivors expressed distinctly lower levels of CSF IL-15 and IL-8 compared with those who died. Survivors of either gender demonstrated a significant increase in the levels of immune regulatory element, IL-10. In the finale, we classified divergent neuroimmune key signatures in CSF by gender, survival, and intragender-specific survival among people with HIV-associated cryptococcal meningitis. These intragender-specific survival associated-neuroimmune signatures, suggests the discrete role of gender immune regulating mechanisms as the possible targets for interventions to advance therapy to improve survival among people with HIV-associated cryptococcal meningitis.

Design of VA CoronavirUs Research and Efficacy Studies-1 (VA CURES-1): A double-blind, randomized placebo-controlled trial of COVID-19 convalescent plasma in hospitalized patients with early respiratory compromise.

Background: Effective therapeutics for severe acute respiratory syndrome CoronaVirus-2 (SARS-CoV-2) infection are evolving. Under Emergency Use Authorization, COVID-19 convalescent plasma (CCP) was widely used in individuals hospitalized for COVID-19, but few randomized controlled trials supported its efficacy to limit respiratory failure or death. Methods: VA CoronavirUs Research and Efficacy Studies-1 (VA CURES-1) was a double-blind, multi-site, placebo-controlled, randomized clinical trial evaluating the efficacy and safety of CCP with conventional therapy in hospitalized Veterans with SARS-CoV-2 infection and early respiratory compromise (requirement for oxygen). Participants (planned sample size 702) were randomized 1:1 to receive CCP with high titer neutralizing activity or 0.9% saline, stratified by site and age (≥65 versus <65 years old). Participants were followed daily during initial hospitalization and at Days 15, 22 and 28. Outcomes: The composite primary outcome was acute hypoxemic respiratory failure or all-cause death by Day 28. Secondary outcomes by day 28 included time-to-recovery, clinical severity, mortality, rehospitalization for COVID-19, and adverse events. Serial respiratory and blood samples were collected for safety, virologic and immunologic analyses and future studies. Key variables in predicting the success of CURES-1 were: (1) enrollment early in the course of severe infection; (2) use of plasma with high neutralizing activity; (3) reliance on unambiguous, clinically meaningful outcomes. CURES-1 was terminated for futility due to perceived inability to enroll in the lull between the Alpha and Delta waves of the SARS CoV-2 epidemic. Conclusions: VA CURES-1 was a large multi-site trial designed to provide conclusive information about the efficacy of CCP in well-characterized patients at risk for progression of COVID-19. It utilized a rigorous study design with relevant initial timing, quality of product and outcomes. Trial registration: ClinicalTrials.gov Identifier: NCT04539275.

Incidence and clinical outcomes of pneumonia in persons with down syndrome in the United States.

BACKGROUND: Persons with Down syndrome (DS) experience an increased risk of pneumonia. We determined the incidence and outcomes of pneumonia and relationship to underlying comorbidities in persons with and without DS in the United States. METHODS: This retrospective matched cohort study used de-identified administrative claims data from Optum. Persons with DS were matched 1:4 to persons without DS on age, sex, and race/ethnicity. Pneumonia episodes were analyzed for incidence, rate ratios and 95 % confidence intervals, clinical outcomes, and comorbidities. RESULTS: During 1-year follow-up among 33796 persons with and 135184 without DS, the incidence of all-cause pneumonia (pneumonia) was substantially higher among people with DS than those without DS (12427 vs. 2531 episodes/100000 person-years; 4.7-5.7 fold increase). Persons with DS and pneumonia were more likely to be hospitalized (39.4 % vs. 13.9 %) or admitted to the ICU (16.8 % vs. 4.8 %). Mortality was higher 1 year after first pneumonia (5.7 % vs. 2.4 %; P < 0.0001). Results were similar for episodes of pneumococcal pneumonia. Specific comorbidities were associated with pneumonia, particularly heart disease in children and neurologic disease in adults, which only partially mediated the effect of DS on pneumonia. CONCLUSIONS: Among persons with DS, incidence of pneumonia and associated hospitalizations were increased; mortality among those with pneumonia was comparable at 30 days, but higher at 1 year. DS should be considered an independent risk condition for pneumonia.

Divergent neuroimmune signatures in the cerebrospinal fluid predict differential gender-specific survival among patients with HIV-associated cryptococcal meningitis.

Introduction: Survival among people with HIV-associated cryptococcal meningitis (CM) remains low, particularly among women, despite the currently optimal use of antifungal drugs. Cryptococcus dissemination into the central nervous system [brain, spinal cord, and cerebrospinal fluid (CSF)] elicits the local production of cytokines, chemokines, and other biomarkers. However, no consistent diagnostic or prognostic neuroimmune signature is reported to underpin the risk of death or to identify mechanisms to improve treatment and survival. We hypothesized that distinct neuroimmune signatures in the CSF would distinguish survivors from people who died on antifungal treatment and who may benefit from tailored therapy. Methods: We considered baseline clinical features, CSF cryptococcal fungal burden, and CSF neuroimmune signatures with survival at 18 weeks among 419 consenting adults by "gender" (168 women and 251 men by biological sex defined at birth). Results: Survival at 18 weeks was significantly lower among women than among men {47% vs. 59%, respectively; hazard ratio (HR) = 1.4 [95% confidence interval (CI), 1.0 to 1.9; p = 0.023]}. Unsupervised principal component analysis (PCA) demonstrated divergent neuroimmune signatures by gender, survival, and intragender-specific survival. Overall, women had lower levels of programmed death ligand 1, Interleukin (IL) (IL-11RA/IL-1F30, and IL-15 (IL-15) than men (all p < 0.028). Female survivors compared with those who died expressed significant elevations in levels of CCL11 and CXCL10 chemokines (both p = 0.001), as well as increased T helper 1, regulatory, and T helper 17 cytokines (all p < 0.041). In contrast, male survivors expressed lower levels of IL-15 and IL-8 compared with men who died (p < 0.044). Conclusions: Survivors of both genders demonstrated a significant increase in the levels of immune regulatory IL-10. In conclusion, the lower survival among women with CM was accompanied by distinct differential gender-specific neuroimmune signatures. These female and male intragender-specific survival-associated neuroimmune signatures provide potential targets for interventions to advance therapy to improve the low survival among people with HIV-associated CM.