Rare Detection of Antiviral Functions of Polyclonal IgA Isolated from Plasma and Breast Milk Compartments in Women Chronically Infected with HIV-1.

The humoral response to invading mucosal pathogens comprises multiple antibody isotypes derived from systemic and mucosal compartments. To understand the contribution of each antibody isotype/source to the mucosal humoral response, parallel investigation of the specificities and functions of antibodies within and across isotypes and compartments is required. The role of IgA against HIV-1 is complex, with studies supporting a protective role as well as a role for serum IgA in blocking effector functions. Thus, we explored the fine specificity and function of IgA in both plasma and mucosal secretions important to infant HIV-1 infection, i.e., breast milk. IgA and IgG were isolated from milk and plasma from 20 HIV-1-infected lactating Malawian women. HIV-1 binding specificities, neutralization potency, inhibition of virus-epithelial cell binding, and antibody-mediated phagocytosis were measured. Fine-specificity mapping showed IgA and IgG responses to multiple HIV-1 Env epitopes, including conformational V1/V2 and linear V2, V3, and constant region 5 (C5). Env IgA was heterogeneous between the milk and systemic compartments (Env IgA, τ = 0.00 to 0.63, P = 0.0046 to 1.00). Furthermore, IgA and IgG appeared compartmentalized as there was a lack of correlation between the specificities of Env-specific IgA and IgG (in milk, τ = -0.07 to 0.26, P = 0.35 to 0.83). IgA and IgG also differed in functions: while neutralization and phagocytosis were consistently mediated by milk and plasma IgG, they were rarely detected in IgA from both milk and plasma. Understanding the ontogeny of the divergent IgG and IgA antigen specificity repertoires and their effects on antibody function will inform vaccination approaches targeted toward mucosal pathogens.IMPORTANCE Antibodies within the mucosa are part of the first line of defense against mucosal pathogens. Evaluating mucosal antibody isotypes, specificities, and antiviral functions in relationship to the systemic antibody profile can provide insights into whether the antibody response is coordinated in response to mucosal pathogens. In a natural immunity cohort of HIV-infected lactating women, we mapped the fine specificity and function of IgA in breast milk and plasma and compared these with the autologous IgG responses. Antigen specificities and functions differed between IgG and IgA, with antiviral functions (neutralization and phagocytosis) predominantly mediated by the IgG fraction in both milk and plasma. Furthermore, the specificity of milk IgA differed from that of systemic IgA. Our data suggest that milk IgA and systemic IgA should be separately examined as potential correlates of risk. Preventive vaccines may need to employ different strategies to elicit functional antiviral immunity by both antibody isotypes in the mucosa.

Infant transmitted/founder HIV-1 viruses from peripartum transmission are neutralization resistant to paired maternal plasma.

Despite extensive genetic diversity of HIV-1 in chronic infection, a single or few maternal virus variants become the founders of an infant's infection. These transmitted/founder (T/F) variants are of particular interest, as a maternal or infant HIV vaccine should raise envelope (Env) specific IgG responses capable of blocking this group of viruses. However, the maternal or infant factors that contribute to selection of infant T/F viruses are not well understood. In this study, we amplified HIV-1 env genes by single genome amplification from 16 mother-infant transmitting pairs from the U.S. pre-antiretroviral era Women Infant Transmission Study (WITS). Infant T/F and representative maternal non-transmitted Env variants from plasma were identified and used to generate pseudoviruses for paired maternal plasma neutralization sensitivity analysis. Eighteen out of 21 (85%) infant T/F Env pseudoviruses were neutralization resistant to paired maternal plasma. Yet, all infant T/F viruses were neutralization sensitive to a panel of HIV-1 broadly neutralizing antibodies and variably sensitive to heterologous plasma neutralizing antibodies. Also, these infant T/F pseudoviruses were overall more neutralization resistant to paired maternal plasma in comparison to pseudoviruses from maternal non-transmitted variants (p = 0.012). Altogether, our findings suggest that autologous neutralization of circulating viruses by maternal plasma antibodies select for neutralization-resistant viruses that initiate peripartum transmission, raising the speculation that enhancement of this response at the end of pregnancy could further reduce infant HIV-1 infection risk.

HIV-Exposed Infants Vaccinated with an MF59/Recombinant gp120 Vaccine Have Higher-Magnitude Anti-V1V2 IgG Responses than Adults Immunized with the Same Vaccine.

In the RV144 vaccine trial, IgG responses against the HIV envelope variable loops 1 and 2 (V1V2) were associated with decreased HIV acquisition risk. We previously reported that infants immunized with an MF59-adjuvanted rgp120 vaccine developed higher-magnitude anti-V1V2 IgG responses than adult RV144 vaccinees. To determine whether the robust antibody response in infants is due to differences in vaccine regimens or to inherent differences between the adult and infant immune systems, we compared Env-specific IgG responses in adults and infants immunized with the same MF59- and alum-adjuvanted HIV envelope vaccines. At peak immunogenicity, the magnitudes of the gp120- and V1V2-specific IgG responses were comparable between adults and infants immunized with the alum/MNrgp120 vaccine (gp120 median fluorescence intensities [FIs] in infants = 7,118 and in adults = 11,510, P = 0.070; V1V2 median MFIs of 512 [infants] and 804 [adults], P = 0.50), whereas infants immunized with the MF59/SF-2 rgp120 vaccine had higher-magnitude antibody levels than adults (gp120 median FIs of 15,509 [infants] and 2,290 [adults], P < 0.001; V1V2 median FIs of 23,926 [infants] and 1,538 [adults]; P < 0.001). Six months after peak immunogenicity, infants maintained higher levels Env-specific IgG than adults. Anti-V1V2 IgG3 antibodies that were associated with decreased HIV-1 risk in RV144 vaccinees were present in 43% of MF59/rgp120-vaccinated infants but only in 12% of the vaccinated adults (P = 0.0018). Finally, in contrast to the rare vaccine-elicited Env-specific IgA in infants, rgp120 vaccine-elicited Env-specific IgA was frequently detected in adults. Our results suggest that vaccine adjuvants differently modulate gp120-specific antibody responses in adults and infants and that infants can robustly respond to HIV Env immunization.IMPORTANCE More than 150,000 pediatric HIV infections occur yearly, despite the availability of antiretroviral prophylaxis. A pediatric HIV vaccine could reduce the number of these ongoing infant infections and also prime for long-term immunity prior to sexual debut. We previously reported that immunization of infants with an MF59-adjuvanted recombinant gp120 vaccine induced higher-magnitude, potentially protective anti-V1V2 IgG responses than in adult vaccinees receiving the moderately effective RV144 vaccine. In the present study, we demonstrate that the robust response observed in infants is not due to differences in vaccine regimen or vaccine dose between adults and infants. Our results suggest that HIV vaccine adjuvants may differentially modulate immune responses in adults and infants, highlighting the need to conduct vaccine trials in pediatric populations.

Maternal Binding and Neutralizing IgG Responses Targeting the C-Terminal Region of the V3 Loop Are Predictive of Reduced Peripartum HIV-1 Transmission Risk.

The development of an effective maternal HIV-1 vaccine that could synergize with antiretroviral therapy (ART) to eliminate pediatric HIV-1 infection will require the characterization of maternal immune responses capable of blocking transmission of autologous HIV to the infant. We previously determined that maternal plasma antibody binding to linear epitopes within the variable loop 3 (V3) region of HIV envelope (Env) and neutralizing responses against easy-to-neutralize tier 1 viruses were associated with reduced risk of peripartum HIV infection in the historic U.S. Woman and Infant Transmission Study (WITS) cohort. Here, we defined the fine specificity and function of the potentially protective maternal V3-specific IgG antibodies associated with reduced peripartum HIV transmission risk in this cohort. The V3-specific IgG binding that predicted low risk of mother-to-child-transmission (MTCT) was dependent on the C-terminal flank of the V3 crown and particularly on amino acid position 317, a residue that has also been associated with breakthrough transmission in the RV144 vaccine trial. Remarkably, the fine specificity of potentially protective maternal plasma V3-specific tier 1 virus-neutralizing responses was dependent on the same region in the V3 loop. Our findings suggest that MTCT risk is associated with neutralizing maternal IgG that targets amino acid residues in the C-terminal region of the V3 loop crown, suggesting the importance of the region in immunogen design for maternal vaccines to prevent MTCT.IMPORTANCE Efforts to curb HIV-1 transmission in pediatric populations by antiretroviral therapy (ART) have been highly successful in both developed and developing countries. However, more than 150,000 infants continue to be infected each year, likely due to a combination of late maternal HIV diagnosis, lack of ART access or adherence, and drug-resistant viral strains. Defining the fine specificity of maternal humoral responses that partially protect against MTCT of HIV is required to inform the development of a maternal HIV vaccine that will enhance these responses during pregnancy. In this study, we identified amino acid residues targeted by potentially protective maternal V3-specific IgG binding and neutralizing responses, localizing the potentially protective response in the C-terminal region of the V3 loop crown. Our findings have important implications for the design of maternal vaccination strategies that could synergize with ART during pregnancy to achieve the elimination of pediatric HIV infections.

Association of HIV-1 Envelope-Specific Breast Milk IgA Responses with Reduced Risk of Postnatal Mother-to-Child Transmission of HIV-1.

UNLABELLED: Infants born to HIV-1-infected mothers in resource-limited areas where replacement feeding is unsafe and impractical are repeatedly exposed to HIV-1 throughout breastfeeding. Despite this, the majority of infants do not contract HIV-1 postnatally, even in the absence of maternal antiretroviral therapy. This suggests that immune factors in breast milk of HIV-1-infected mothers help to limit vertical transmission. We compared the HIV-1 envelope-specific breast milk and plasma antibody responses of clade C HIV-1-infected postnatally transmitting and nontransmitting mothers in the control arm of the Malawi-based Breastfeeding Antiretrovirals and Nutrition Study using multivariable logistic regression modeling. We found no association between milk or plasma neutralization activity, antibody-dependent cell-mediated cytotoxicity, or HIV-1 envelope-specific IgG responses and postnatal transmission risk. While the envelope-specific breast milk and plasma IgA responses also did not reach significance in predicting postnatal transmission risk in the primary model after correction for multiple comparisons, subsequent exploratory analysis using two distinct assay methodologies demonstrated that the magnitudes of breast milk total and secretory IgA responses against a consensus HIV-1 envelope gp140 (B.con env03) were associated with reduced postnatal transmission risk. These results suggest a protective role for mucosal HIV-1 envelope-specific IgA responses in the context of postnatal virus transmission. This finding supports further investigations into the mechanisms by which mucosal IgA reduces risk of HIV-1 transmission via breast milk and into immune interventions aimed at enhancing this response. IMPORTANCE: Infants born to HIV-1-infected mothers are repeatedly exposed to the virus in breast milk. Remarkably, the transmission rate is low, suggesting that immune factors in the breast milk of HIV-1-infected mothers help to limit transmission. We compared the antibody responses in plasma and breast milk of HIV-1-transmitting and -nontransmitting mothers to identify responses that correlated with reduced risk of postnatal HIV-1 transmission. We found that neither plasma nor breast milk IgG antibody responses were associated with risk of HIV-1 transmission. In contrast, the magnitudes of the breast milk IgA and secretory IgA responses against HIV-1 envelope proteins were associated with reduced risk of postnatal HIV-1 transmission. The results of this study support further investigations of the mechanisms by which mucosal IgA may reduce the risk of HIV-1 transmission via breastfeeding and the development of strategies to enhance milk envelope-specific IgA responses to reduce mother-to-child HIV transmission and promote an HIV-free generation.

The use of the Gail model, body mass index and SNPs to predict breast cancer among women with abnormal (BI-RADS 4) mammograms.

INTRODUCTION: Mammography screening results in a significant number of false-positives. The use of pretest breast cancer risk factors to guide follow-up of abnormal mammograms could improve the positive predictive value of screening. We evaluated the use of the Gail model, body mass index (BMI), and genetic markers to predict cancer diagnosis among women with abnormal mammograms. We also examined the extent to which pretest risk factors could reclassify women without cancer below the biopsy threshold. METHODS: We recruited a prospective cohort of women referred for biopsy with abnormal (BI-RADS 4) mammograms according to the American College of Radiology's Breast Imaging-Reporting and Data System (BI-RADS). Breast cancer risk factors were assessed prior to biopsy. A validated panel of 12 single-nucleotide polymorphisms (SNPs) associated with breast cancer were measured. Logistic regression was used to assess the association of Gail risk factors, BMI and SNPs with cancer diagnosis (invasive or ductal carcinoma in situ). Model discrimination was assessed using the area under the receiver operating characteristic curve, and calibration was assessed using the Hosmer-Lemeshow goodness-of-fit test. The distribution of predicted probabilities of a cancer diagnosis were compared for women with or without breast cancer. RESULTS: In the multivariate model, age (odds ratio (OR)=1.05; 95% confidence interval (CI), 1.03 to 1.08; P<0.001), SNP panel relative risk (OR=2.30; 95% CI, 1.06 to 4.99, P=0.035) and BMI (≥30 kg/m2 versus <25 kg/m(2); OR=2.20; 95% CI, 1.05 to 4.58; P=0.036) were significantly associated with breast cancer diagnosis. Older women were more likely than younger women to be diagnosed with breast cancer. The SNP panel relative risk remained strongly associated with breast cancer diagnosis after multivariable adjustment. Higher BMI was also strongly associated with increased odds of a breast cancer diagnosis. Obese women (OR=2.20; 95% CI, 1.05 to 4.58; P=0.036) had more than twice the odds of cancer diagnosis compared to women with a BMI<25 kg/m2. The SNP panel appeared to have predictive ability among both white and black women. CONCLUSIONS: Breast cancer risk factors, including BMI and genetic markers, are predictive of cancer diagnosis among women with BI-RADS 4 mammograms. Using pretest risk factors to guide follow-up of abnormal mammograms could reduce the burden of false-positive mammograms.

A Multicenter Retrospective Study Evaluating Intravenous to Oral Antibiotic Stepdown for Uncomplicated Streptococcal Bacteremia.

Background: The purpose of this study was to compare the efficacy and safety of intravenous (IV) versus oral (PO) stepdown therapy for uncomplicated streptococcal bacteremia. Methods: This multicenter, retrospective study included adult patients with uncomplicated streptococcal bacteremia between 1 July 2019 and 1 July 2022. Patients who received IV therapy for the full treatment course were compared to patients who transitioned to PO therapy after initial IV therapy. The primary outcome was clinical success, defined as absence of infection recurrence, infection-related readmission, and infection-related mortality at 90 days. Secondary outcomes included microbiological success, length of stay (LOS), and IV line-associated complications. Results: Of 238 patients included, 47.1% received PO stepdown therapy. Clinical success occurred in 94.4% and 94.6% in the IV only and PO stepdown groups, respectively (P = .946). Patients who transitioned to PO therapy received a median duration of IV therapy of 3.9 days (interquartile range, 2.9-7.3 days). Line complications were more frequent in the IV only group, primarily driven by catheter-related infections (7.2% vs 0%, P = .002). LOS was significantly shorter in the PO stepdown group (5.5 vs 9.2 days, P < .001). Conclusions: Patients transitioned to PO antibiotics for uncomplicated streptococcal bacteremia had similar rates of clinical success compared to patients who received only IV therapy. With consideration of infectious source, severity of illness, and comorbidities, PO stepdown following initial IV antibiotics for uncomplicated streptococcal bacteremia in select patients is a reasonable approach that may result in decreased LOS and line-related complications.

Incremental impact of breast cancer SNP panel on risk classification in a screening population of white and African American women.

Breast cancer risk prediction remains imperfect, particularly among non-white populations. This study examines the impact of including single-nucleotide polymorphism (SNP) alleles in risk prediction for white and African American women undergoing screening mammogram. Using a prospective cohort study, standard risk information and buccal swabs were collected at the time of screening mammography. A 12 SNP panel was performed by deCODE genetics. Five-year and lifetime risks incorporating SNPs were calculated by multiplying estimated Breast Cancer Risk Assessment Tool (BCRAT) risk by the total genetic risk ratio. Concordance between the BCRAT and the combined model (BCRAT + SNPs) in identifying high-risk women was measured using the kappa statistic. SNP data were available for 810 women (39 % African American, 55 % white). The mean BCRAT 5-year risk was 1.71 % for whites and 1.18 % for African Americans. Mean genetic risk ratios were 1.09 in whites and 1.29 in African Americans. Among whites, three SNPs had higher frequencies, and among African Americans, seven SNPs had higher and four had lower high-risk allele frequencies than previously reported. Agreement between the BCRAT and the combined model was relatively low for identifying high-risk women (5-year κ = 0.54, lifetime κ = 0.36). Addition of SNPs had the greatest effect among African Americans, with 12.4 % identified as having high-5-year risk by BCRAT, but 33 % by the combined model. A greater proportion of African Americans were reclassified as having high-5-year risk than whites using the combined model (21 vs. 10 %). The addition of SNPs to the BCRAT reclassifies the high-risk status of some women undergoing screening mammography, particularly African Americans. Further research is needed to determine the clinical validity and utility of the SNP panel for use in breast cancer risk prediction, particularly among African Americans for whom these risk alleles have generally not been validated.

Orexinergic activity modulates altered vital signs and pituitary hormone secretion in experimental sepsis.

OBJECTIVES: Sepsis is a common, lethal poorly understood disorder affecting nearly a million Americans annually. The syndrome is characterized by altered cardiodynamics, respiration, metabolism, pituitary function, arousal, and impaired interaction among organ systems. The immunologic and endocrine systems, which are in part responsible for organ-organ communication, have been studied extensively in sepsis. However, little is known about sepsis-induced changes in central nervous system activity. HYPOTHESIS: A defect in hypothalamic neurons secreting the neurotransmitter orexin modulates physiologic derangements in sepsis. DESIGN: Animal study. SETTING: University Research Laboratory. INTERVENTIONS: Male C57Bl6 mice were made septic using cecal ligation and puncture. Data were collected 24 or 48 hours later, blood was collected, animals were killed, and brain tissue was harvested, fixed, and sectioned. Hypothalamic sections were subjected to immunohistochemistry using antibodies to orexin and c-Fos, a marker of neuronal activity. In a separate cohort of mice, cannulas were placed in the right lateral cerebral ventricle. Cecal ligation and puncture was performed 1 week later. At 24 or 48 hours post-cecal ligation and puncture, vital signs were measured, and1 µL of saline with or without 3 nmol orexin-A was infused. Vital signs were repeated at 25 or 49 hours post-cecal ligation and puncture, blood was collected, animals were killed, and brains were removed, fixed, sectioned, and stained. MEASUREMENTS AND MAIN RESULTS: Orexinergic activity decreased six-fold following cecal ligation and puncture. This change was associated with decreases in arousal, temperature, and heart and respiratory rates. Levels of selected pituitary hormones increased 24 hours post-cecal ligation and puncture but were significantly lower than baseline at 48 hours. Injection of orexin-A increased vital signs to baseline levels. Hormone levels were unaffected at 25 hours but increased to supranormal levels at 49 hours. CONCLUSIONS: Sepsis-induced changes in activity, vital signs, and pituitary hormones are modulated by the orexinergic system. This finding implicates central nervous system dysfunction in the pathogenesis of sepsis, suggesting further study of neurological dysfunction to identify novel approaches to management.

Transposable Elements in Bats Show Differential Accumulation Patterns Determined by Class and Functionality.

Bat genomes are characterized by a diverse transposable element (TE) repertoire. In particular, the genomes of members of the family Vespertilionidae contain both active retrotransposons and active DNA transposons. Each TE type is characterized by a distinct pattern of accumulation over the past ~40 million years. Each also exhibits its own target site preferences (sometimes shared with other TEs) that impact where they are likely to insert when mobilizing. Therefore, bats provide a great resource for understanding the diversity of TE insertion patterns. To gain insight into how these diverse TEs impact genome structure, we performed comparative spatial analyses between different TE classes and genomic features, including genic regions and CpG islands. Our results showed a depletion of all TEs in the coding sequence and revealed patterns of species- and element-specific attraction in the transcript. Trends of attraction in the distance tests also suggested significant TE activity in regions adjacent to genes. In particular, the enrichment of small, non-autonomous TE insertions in introns and near coding regions supports the hypothesis that the genomic distribution of TEs is the product of a balance of the TE insertion preference in open chromatin regions and the purifying selection against TEs within genes.

Abdominal migraine: an under-diagnosed cause of recurrent abdominal pain in children.

OBJECTIVE: Our objective was to demonstrate that, despite recognition by both the gastroenterology and headache communities, abdominal migraine (AM) is an under-diagnosed cause of chronic, recurrent, abdominal pain in childhood in the USA. BACKGROUND: Chronic, recurrent abdominal pain occurs in 9-15% of all children and adolescents. After exclusion of anatomic, infectious, inflammatory, or other metabolic causes, "functional abdominal pain" is the most common diagnosis of chronic, idiopathic, abdominal pain in childhood. Functional abdominal pain is typically categorized into one, or a combination of, the following 4 groups: functional dyspepsia, irritable bowel syndrome, AM, or functional abdominal pain syndrome. International Classification of Headache Disorders--(ICHD-2) defines AM as an idiopathic disorder characterized by attacks of midline, moderate to severe abdominal pain lasting 1-72 hours with vasomotor symptoms, nausea and vomiting, and included AM among the "periodic syndromes of childhood that are precursors for migraine." Rome III Gastroenterology criteria (2006) separately established diagnostic criteria and confirmed AM as a well-defined cause of recurrent abdominal pain. METHODS: Following institutional review board approval, a retrospective chart review was conducted on patients referred to an academic pediatric gastroenterology practice with the clinical complaint of recurrent abdominal pain. ICHD-2 criteria were applied to identify the subset of children fulfilling criteria for AM. Demographics, diagnostic evaluation, treatment regimen and outcomes were collected. RESULTS: From an initial cohort of 600 children (ages 1-21 years; 59% females) with recurrent abdominal pain, 142 (24%) were excluded on the basis of their ultimate diagnosis. Of the 458 patients meeting inclusion criteria, 1824 total patient office visits were reviewed. Three hundred eighty-eight (84.6%) did not meet criteria for AM, 20 (4.4%) met ICHD-2 formal criteria for AM and another 50 (11%) had documentation lacking at least 1 criterion, but were otherwise consistent with AM (probable AM). During the observation period, no children seen in this gastroenterology practice had received a diagnosis of AM. CONCLUSION: Among children with chronic, idiopathic, recurrent abdominal pain, AM represents about 4-15%. Given the spectrum of treatment modalities now available for pediatric migraine, increased awareness of cardinal features of AM by pediatricians and pediatric gastroenterologists may result in improved diagnostic accuracy and early institution of both acute and preventative migraine-specific treatments.

Potential barriers to adherence in pediatric dermatology.

This study sought to identify barriers to treatment in children with chronic inflammatory skin disease, particularly those with atopic dermatitis, psoriasis, and acne vulgaris. Caregivers of 101 patients seen in the Children's Specialty Group Division of Dermatology, Children's Hospital of The King's Daughters, Norfolk, Virginia, completed an 11-item Likert scale questionnaire. This survey addressed complexity and time requirements for treatment, medication cost, vehicle formulation, perceived safety, and caregiver understanding of chronicity of skin disorders. Parents and caregivers indicated that adequate instructions for using the medications were provided but that they felt less comfortable with treating their child's skin disease during a severe flare. The complexity of treatment programs, time required to apply medications, and vehicle type were not considered prohibitive factors. Caregivers were concerned about the cost and safety of prescribed medications and had a less understanding of the chronicity of inflammatory skin disorders.

Induction of Neutralizing Responses against Autologous Virus in Maternal HIV Vaccine Trials.

A maternal vaccine capable of boosting neutralizing antibody (NAb) responses directed against circulating viruses in HIV-infected pregnant women could effectively decrease mother-to-child transmission of HIV. However, it is not known if an HIV envelope (Env) vaccine administered to infected pregnant women could enhance autologous virus neutralization and thereby reduce this risk of vertical HIV transmission. Here, we assessed autologous virus NAb responses in maternal plasma samples obtained from AIDS Vaccine Evaluation Group (AVEG) protocols 104 and 102, representing historical phase I safety and immunogenicity trials of recombinant HIV Env subunit vaccines administered to HIV-infected pregnant women (ClinicalTrials registration no. NCT00001041). Maternal HIV Env-specific plasma binding and neutralizing antibody responses were characterized before and after vaccination in 15 AVEG 104 (n = 10 vaccine recipients, n = 5 placebo recipients) and 2 AVEG 102 (n = 1 vaccine recipient, n = 1 placebo recipient) participants. Single-genome amplification (SGA) was used to obtain HIV env gene sequences of autologous maternal viruses for pseudovirus production and neutralization sensitivity testing in pre- and postvaccination plasma of HIV-infected pregnant vaccine recipients (n = 6 gp120, n = 1 gp160) and placebo recipients (n = 3). We detected an increase in Env subunit MN gp120-specific IgG binding in the group of vaccine recipients between the first immunization visit and the last visit at delivery (P = 0.027, 2-sided Wilcoxon test). While no difference was observed in the levels of autologous virus neutralization potency between groups, in both groups maternal plasma collected at delivery more effectively neutralized autologous viruses from early pregnancy than late pregnancy. Immunization strategies capable of further enhancing these autologous virus NAb responses in pregnant women will be important to block vertical transmission of HIV.IMPORTANCE Maternal antiretroviral therapy (ART) has effectively reduced but not eliminated the burden of mother-to-child transmission of HIV across the globe, as an estimated 160,000 children were newly infected with HIV in 2018. Thus, additional preventive strategies beyond ART will be required to close the remaining gap and end the pediatric HIV epidemic. A maternal active immunization strategy that synergizes with maternal ART could further reduce infant HIV infections. In this study, we found that two historic HIV Env vaccines did not enhance the ability of HIV-infected pregnant women to neutralize autologous viruses. Therefore, next-generation maternal HIV vaccine candidates must employ alternate approaches to achieve potent neutralizing antibody and perhaps nonneutralizing antibody responses to effectively impede vertical virus transmission. Moreover, these approaches must reflect the broad diversity of HIV strains and widespread availability of ART worldwide.

Development and application of a multiplex assay for the simultaneous measurement of antibody responses elicited by common childhood vaccines.

Because vaccine co-administration can affect elicited immune responses, it is important to evaluate new vaccines in the context of pre-existing vaccination schedules. This is particularly necessary for new pediatric vaccines, as the World Health Organization's infant immunization program already schedules several vaccines to be administered during the first months of life. To facilitate the assessment of inter-vaccine interference, we developed a pediatric vaccine multiplex assay (PVMA) to simultaneously measure antibodies against vaccines commonly administered to infants, including hepatitis B, Haemophilus influenzae type B, diphtheria, tetanus, pertussis, rubella, and respiratory syncytial virus (RSV). Comparison of antibody concentrations determined by enzyme-linked immunosorbent assays (ELISAs) and the PVMA demonstrated that the PVMA is highly sensitive, specific, reproducible, and accurate. Moreover, the PVMA requires half the time to assess a cohort compared to ELISAs, and only costs marginally more. Demonstrating the utility of the assay, we employed the PVMA to assess vaccine interference in the setting of a candidate vaccine, using the infant HIV vaccines from the completed Pediatric AIDS Clinical Trials Group (PACTG) protocols 230 and 326 as examples. There was no substantial difference in antibody concentrations between vaccine and placebo recipients, which suggests that HIV vaccination did not disrupt antibody responses elicited by routine pediatric vaccines. Thus, the PVMA is a reliable, high-throughput technique that requires minimal sample volume to measure multiple antibody concentrations concurrently, and is an efficient alternative to ELISAs for the measurement of vaccine-elicited antibody responses in large cohorts.

Maternal Humoral Immune Correlates of Peripartum Transmission of Clade C HIV-1 in the Setting of Peripartum Antiretrovirals.

Despite the widespread use of antiretrovirals (ARV), more than 150,000 pediatric HIV-1 infections continue to occur annually. Supplemental strategies are necessary to eliminate pediatric HIV infections. We previously reported that maternal HIV envelope-specific anti-V3 IgG and CD4 binding site-directed antibodies, as well as tier 1 virus neutralization, predicted a reduced risk of mother-to-child transmission (MTCT) of HIV-1 in the pre-ARV era U.S.-based Women and Infants Transmission Study (WITS) cohort. As the majority of ongoing pediatric HIV infections occur in sub-Saharan Africa, we sought to determine if the same maternal humoral immune correlates predicted MTCT in a subset of the Malawian Breastfeeding, Antiretrovirals, and Nutrition (BAN) cohort of HIV-infected mothers (n = 88, with 45 transmitting and 43 nontransmitting). Women and infants received ARV at delivery; thus, the majority of MTCT was in utero (91%). In a multivariable logistic regression model, neither maternal anti-V3 IgG nor clade C tier 1 virus neutralization was associated with MTCT. Unexpectedly, maternal CD4 binding-site antibodies and anti-variable loop 1 and 2 (V1V2) IgG were associated with increased MTCT, independent of maternal viral load. Neither infant envelope (Env)-specific IgG levels nor maternal IgG transplacental transfer efficiency was associated with transmission. Distinct humoral immune correlates of MTCT in the BAN and WITS cohorts could be due to differences between transmission modes, virus clades, or maternal antiretroviral use. The association between specific maternal antibody responses and in utero transmission, which is distinct from potentially protective maternal antibodies in the WITS cohort, underlines the importance of investigating additional cohorts with well-defined transmission modes to understand the role of antibodies during HIV-1 MTCT.

The Presence and Anti-HIV-1 Function of Tenascin C in Breast Milk and Genital Fluids.

Tenascin-C (TNC) is a newly identified innate HIV-1-neutralizing protein present in breast milk, yet its presence and potential HIV-inhibitory function in other mucosal fluids is unknown. In this study, we identified TNC as a component of semen and cervical fluid of HIV-1-infected and uninfected individuals, although it is present at a significantly lower concentration and frequency compared to that of colostrum and mature breast milk, potentially due to genital fluid protease degradation. However, TNC was able to neutralize HIV-1 after exposure to low pH, suggesting that TNC could be active at low pH in the vaginal compartment. As mucosal fluids are complex and contain a number of proteins known to interact with the HIV-1 envelope, we further studied the relationship between the concentration of TNC and neutralizing activity in breast milk. The amount of TNC correlated only weakly with the overall innate HIV-1-neutralizing activity of breast milk of uninfected women and negatively correlated with neutralizing activity in milk of HIV-1 infected women, indicating that the amount of TNC in mucosal fluids is not adequate to impede HIV-1 transmission. Moreover, the presence of polyclonal IgG from milk of HIV-1 infected women, but not other HIV-1 envelope-binding milk proteins or monoclonal antibodies, blocked the neutralizing activity of TNC. Finally, as exogenous administration of TNC would be necessary for it to mediate measurable HIV-1 neutralizing activity in mucosal compartments, we established that recombinantly produced TNC has neutralizing activity against transmitted/founder HIV-1 strains that mimic that of purified TNC. Thus, we conclude that endogenous TNC concentration in mucosal fluids is likely inadequate to block HIV-1 transmission to uninfected individuals.

Comparative phenotypic and CARD15 mutational analysis among African American, Hispanic, and White children with Crohn's disease.

BACKGROUND: Despite a large body of literature on the subject of Crohn's disease (CD), very little information is available on racial/ethnic differences related to disease presentation, clinical course, and genetics. The first identified CD susceptibility gene, CARD15, seems to be present in up to 40% of white children with CD. However, the frequency of this gene among patients with CD of other racial/ethnic groups in the United States is not known. METHODS: We conducted a multicenter study on African American and Hispanic children with CD to describe the phenotypic and genotypic (CARD15) features in comparison with white children with CD. We also analyzed the frequency of CARD15 mutations in large control samples from white, African American, and Hispanic children. RESULTS: The disease location and behavior were similar among all 3 groups, with inflammatory behavior and the ileocolonic location being the most frequent phenotype. However, significantly lower frequencies of CARD15 mutations were seen in African American (P < 0.0001) and Hispanic (P < 0.0001) children with CD compared with white children with CD. This lower CARD15 frequency among African American patients with CD was also mirrored in the general population. CONCLUSIONS: Phenotypic features of CD are similar among African American and Hispanic children compared with white children. CARD15 mutations are not increased among African American and Hispanic children with CD. CARD15 mutational frequencies among African American and Hispanic children within the general population are lower compared with white children within the general population. Future genetics studies will be required to determine the relationships between genotype and CD phenotype in various ethnic and racial groups.

Programmed evolution for optimization of orthogonal metabolic output in bacteria.

Current use of microbes for metabolic engineering suffers from loss of metabolic output due to natural selection. Rather than combat the evolution of bacterial populations, we chose to embrace what makes biological engineering unique among engineering fields - evolving materials. We harnessed bacteria to compute solutions to the biological problem of metabolic pathway optimization. Our approach is called Programmed Evolution to capture two concepts. First, a population of cells is programmed with DNA code to enable it to compute solutions to a chosen optimization problem. As analog computers, bacteria process known and unknown inputs and direct the output of their biochemical hardware. Second, the system employs the evolution of bacteria toward an optimal metabolic solution by imposing fitness defined by metabolic output. The current study is a proof-of-concept for Programmed Evolution applied to the optimization of a metabolic pathway for the conversion of caffeine to theophylline in E. coli. Introduced genotype variations included strength of the promoter and ribosome binding site, plasmid copy number, and chaperone proteins. We constructed 24 strains using all combinations of the genetic variables. We used a theophylline riboswitch and a tetracycline resistance gene to link theophylline production to fitness. After subjecting the mixed population to selection, we measured a change in the distribution of genotypes in the population and an increased conversion of caffeine to theophylline among the most fit strains, demonstrating Programmed Evolution. Programmed Evolution inverts the standard paradigm in metabolic engineering by harnessing evolution instead of fighting it. Our modular system enables researchers to program bacteria and use evolution to determine the combination of genetic control elements that optimizes catabolic or anabolic output and to maintain it in a population of cells. Programmed Evolution could be used for applications in energy, pharmaceuticals, chemical commodities, biomining, and bioremediation.

Agreement of self-reported hormone receptor status with cancer registry data in young breast cancer patients.

BACKGROUND: Though breast cancer subtype is a key determinant of treatment choice and prognosis, few studies have assessed breast cancer patients' knowledge of estrogen and progesterone receptor (ER/PR) status. METHODS: Women diagnosed with invasive breast cancer at age 18-64 years in 2007 were recruited from the Pennsylvania Cancer Registry, and mailed a questionnaire that asked respondents to identify their ER/PR status. There were 2191 respondents included in the analysis. Agreement between self-report and cancer registry ER/PR status was assessed using kappa statistic. Logistic regression was used to assess the association of demographic, socioeconomic, and tumor factors with inaccurate self-report of ER/PR status. RESULTS: Fifty-nine percent of respondents reported ER/PR positive status, 15% reported ER/PR negative status, 17% responded 'don't know', and 9% did not respond. Overall, there was 69% agreement between self-report and cancer registry data, and fair agreement as measured by kappa (0.36). After excluding women who did not know or did not report their ER/PR status, there was 93% agreement, and substantial agreement as measured by kappa (0.76). Women who were older, non-white, less educated, lower income, and had ER/PR negative disease were significantly more likely to inaccurately report their ER/PR status. CONCLUSIONS: Though a significant proportion of women do not know their hormone receptor status, women who reported their ER/PR status were accurate. Our results suggest room for improvement in patient knowledge of tumor subtypes, but also that self-reported ER/PR status may be a useful surrogate when medical record or cancer registry data is unavailable.

Effective analgesia using physical interventions for infant immunizations.

BACKGROUND: To measure the analgesic effectiveness of the 5 S's (swaddling, side/stomach position, shushing, swinging, and sucking) alone and combined with sucrose, during routine immunizations at 2 and 4 months. METHODS: We conducted a prospective, randomized, placebo-controlled trial with 2- and 4-month-old infants during well-child visits. Patients were assigned into 4 groups (2 × 2) receiving either 2 mL of water or 2 mL of 24% oral sucrose and then either standard-of-care comfort measures by parents or intervention with the 5 S's immediately postvaccination. The Modified Riley Pain Score was used to score the infants' pain at 15-second intervals for 2 minutes, then every 30 seconds up to 5 minutes postvaccination. Repeated-measures analysis of variance examined between group differences and within-subject variability of treatment effect on overall pain scores and length of crying. RESULTS: Two hundred thirty infants were enrolled. Results revealed significantly different mean pain scores between study groups with the exception of the 5S's and 5S's with sucrose groups. These 2 groups had lower similar mean scores over time, followed by sucrose alone, then control. The same trend was found with the proportion of children crying as with the mean pain score outcome measure. CONCLUSIONS: Physical intervention of the 5 S's (swaddling, side/stomach position, shushing, swinging, and sucking) provided decreased pain scores on a validated pain scale and decreased crying time among 2- and 4-month-old infants during routine vaccinations. The use of 5S's did not differ from 5S's and sucrose.