Potential false-positive urine Legionella enzyme immunoassay test results.

The objective of this study was to identify potential false-positive urine Legionella pneumophila (Legionella) enzyme immunoassay test results. A total of 107 consecutive patients with positive EIA tests were retrospectively analyzed over a 34-month period. Concurrent blood, urine, and sputum cultures, as well as chest radiographic findings, were reviewed in these patients. Twenty patients (19%) had no radiographic evidence of pulmonary disease despite a positive EIA test. In those 20 patients, 14 also had growth of non-Legionella bacteria. Of patients with an infiltrate or opacity on chest imaging, only 27 had Legionella sputum cultures obtained, with Legionella culture growth occurring in 7 (26%). Nine other patients had negative Legionella sputum cultures but the growth of another pathogenic organism in blood, sputum, and/or urine cultures. Pseudomonas aeruginosa was the most common organism isolated, found in 20% of patients in the entire cohort. Twenty-five patients (23%) were characterized as having probable false-positive Legionella urinary antigen EIA testing, and an additional 17 patients (16%) were characterized as having possible false-positive Legionella EIA tests. Our findings suggest that urine Legionella EIA tests may lead to a substantial number of cases being misdiagnosed as Legionaries' disease in patients with non-Legionella bacterial colonization or infection.

Widespread Virus Replication in Alveoli Drives Acute Respiratory Distress Syndrome in Aerosolized H5N1 Influenza Infection of Macaques.

Human infections with highly pathogenic avian influenza A (H5N1) virus are frequently fatal but the mechanisms of disease remain ill-defined. H5N1 infection is associated with intense production of proinflammatory cytokines, but whether this cytokine storm is the main cause of fatality or is a consequence of extensive virus replication that itself drives disease remains controversial. Conventional intratracheal inoculation of a liquid suspension of H5N1 influenza virus in nonhuman primates likely results in efficient clearance of virus within the upper respiratory tract and rarely produces severe disease. We reasoned that small particle aerosols of virus would penetrate the lower respiratory tract and blanket alveoli where target cells reside. We show that inhalation of aerosolized H5N1 influenza virus in cynomolgus macaques results in fulminant pneumonia that rapidly progresses to acute respiratory distress syndrome with a fatal outcome reminiscent of human disease. Molecular imaging revealed intense lung inflammation coincident with massive increases in proinflammatory proteins and IFN-α in distal airways. Aerosolized H5N1 exposure decimated alveolar macrophages, which were widely infected and caused marked influx of interstitial macrophages and neutrophils. Extensive infection of alveolar epithelial cells caused apoptosis and leakage of albumin into airways, reflecting loss of epithelial barrier function. These data establish inhalation of aerosolized virus as a critical source of exposure for fatal human infection and reveal that direct viral effects in alveoli mediate H5N1 disease. This new nonhuman primate model will advance vaccine and therapeutic approaches to prevent and treat human disease caused by highly pathogenic avian influenza viruses.

Cell-Mediated Immunity Against Antigenically Drifted Influenza A(H3N2) Viruses in Children During a Vaccine Mismatch Season.

BACKGROUND: Emergence of antigenically drifted influenza A(H3N2) viruses resulted in reduced vaccine effectiveness in all age groups during the 2014-2015 influenza season. In children, inactivated influenza vaccine (IIV) elicited neutralizing antibodies (Abs) against drifted strains at significantly lower levels than against the vaccine strain. Little is known about the cross-reactivity of cell-mediated immunity against drifted strains in children. METHODS: Children aged 3-17 years (n = 48) received IIV during the 2014-2015 influenza season. Peripheral blood mononuclear cells, collected before (on day 0) and after (on days 7 and 21) vaccination were evaluated for induction of cross-reactive plasmablasts, memory B cells, and cytokine-secreting CD4(+) and CD8(+) T cells against the vaccine and drifted A(H3N2) viruses by an enzyme-linked immunospot assay and flow cytometry. RESULTS: IIV increased frequencies of plasmablasts and memory B cells. The overall induction of the T-cell response was not significant. Both B-cell and T-cell responses showed significant cross-reactivity against A(H3N2) viruses. Age and preexisting immunity affected virus-specific plasmablast responses and fold-change of T-cell responses, respectively. The proportion of T-helper type 1-prone (ie, interferon γ- or tumor necrosis factor α-secreting) CD4(+) T cell responses also increased with age. CONCLUSIONS: In children aged 3-17 years, B- and T-cell responses following IIV receipt showed significant cross-reactivity against A(H3N2) viruses during a vaccine mismatch season.

Characterization and Implementation of a Diverse Simian Immunodeficiency Virus SIVsm Envelope Panel in the Assessment of Neutralizing Antibody Breadth Elicited in Rhesus Macaques by Multimodal Vaccines Expressing the SIVmac239 Envelope.

UNLABELLED: Antibodies that can neutralize diverse viral strains are likely to be an important component of a protective human immunodeficiency virus type 1 (HIV-1) vaccine. To this end, preclinical simian immunodeficiency virus (SIV)-based nonhuman primate immunization regimens have been designed to evaluate and enhance antibody-mediated protection. However, these trials often rely on a limited selection of SIV strains with extreme neutralization phenotypes to assess vaccine-elicited antibody activity. To mirror the viral panels used to assess HIV-1 antibody breadth, we created and characterized a novel panel of 14 genetically and phenotypically diverse SIVsm envelope (Env) glycoproteins. To assess the utility of this panel, we characterized the neutralizing activity elicited by four SIVmac239 envelope-expressing DNA/modified vaccinia virus Ankara vector- and protein-based vaccination regimens that included the immunomodulatory adjuvants granulocyte-macrophage colony-stimulating factor, Toll-like receptor (TLR) ligands, and CD40 ligand. The SIVsm Env panel exhibited a spectrum of neutralization sensitivity to SIV-infected plasma pools and monoclonal antibodies, allowing categorization into three tiers. Pooled sera from 91 rhesus macaques immunized in the four trials consistently neutralized only the highly sensitive tier 1a SIVsm Envs, regardless of the immunization regimen. The inability of vaccine-mediated antibodies to neutralize the moderately resistant tier 1b and tier 2 SIVsm Envs defined here suggests that those antibodies were directed toward epitopes that are not accessible on most SIVsm Envs. To achieve a broader and more effective neutralization profile in preclinical vaccine studies that is relevant to known features of HIV-1 neutralization, more emphasis should be placed on optimizing the Env immunogen, as the neutralization profile achieved by the addition of adjuvants does not appear to supersede the neutralizing antibody profile determined by the immunogen. IMPORTANCE: Many in the HIV/AIDS vaccine field believe that the ability to elicit broadly neutralizing antibodies capable of blocking genetically diverse HIV-1 variants is a critical component of a protective vaccine. Various SIV-based nonhuman primate vaccine studies have investigated ways to improve antibody-mediated protection against a heterologous SIV challenge, including administering adjuvants that might stimulate a greater neutralization breadth. Using a novel SIV neutralization panel and samples from four rhesus macaque vaccine trials designed for cross comparison, we show that different regimens expressing the same SIV envelope immunogen consistently elicit antibodies that neutralize only the very sensitive tier 1a SIV variants. The results argue that the neutralizing antibody profile elicited by a vaccine is primarily determined by the envelope immunogen and is not substantially broadened by including adjuvants, resulting in the conclusion that the envelope immunogen itself should be the primary consideration in efforts to elicit antibodies with greater neutralization breadth.

Comparision of how old age psychiatry and general adult psychiatry services meet the needs of elderly people with functional mental illness: cross-sectional survey.

BACKGROUND: There is little research evidence as to whether general adult psychiatry or old age psychiatry should look after old people with enduring mental illness. AIMS: To compare the extent to which general adult and old age psychiatric services meet the needs of older people with enduring mental illness. METHOD: A total of 74 elderly patients with functional psychiatric disorders were identified by reviewing the notes of patients over the age of 60 living in a defined inner urban catchment area. Data were collected on the morbidity and needs of the sample. Needs were assessed using the Elderly Psychiatric Needs Schedule (EPNS). RESULTS: The participants in contact with old age psychiatry had significantly fewer unmet needs compared with those in contact with general adult psychiatry (2.8 v. 5.6, t = 2.2, P<0.03). Total needs were not significantly different between those managed by old age and general adult services (8.0 v. 6.5 respectively, t = 1.2, P = 0.2). CONCLUSIONS: This study found that old age psychiatry services were better placed to meet the needs of elderly people with mental illness. This finding supports the need for a separate old age psychiatry service.

Live attenuated mutants of Francisella tularensis protect rabbits against aerosol challenge with a virulent type A strain.

Francisella tularensis, a Gram-negative bacterium, is the causative agent of tularemia. No licensed vaccine is currently available for protection against tularemia, although an attenuated strain, dubbed the live vaccine strain (LVS), is given to at-risk laboratory personnel as an investigational new drug (IND). In an effort to develop a vaccine that offers better protection, recombinant attenuated derivatives of a virulent type A strain, SCHU S4, were evaluated in New Zealand White (NZW) rabbits. Rabbits vaccinated via scarification with the three attenuated derivatives (SCHU S4 ΔguaBA, ΔaroD, and ΔfipB strains) or with LVS developed a mild fever, but no weight loss was detected. Twenty-one days after vaccination, all vaccinated rabbits were seropositive for IgG to F. tularensis lipopolysaccharide (LPS). Thirty days after vaccination, all rabbits were challenged with aerosolized SCHU S4 at doses ranging from 50 to 500 50% lethal doses (LD50). All rabbits developed fevers and weight loss after challenge, but the severity was greater for mock-vaccinated rabbits. The ΔguaBA and ΔaroD SCHU S4 derivatives provided partial protection against death (27 to 36%) and a prolonged time to death compared to results for the mock-vaccinated group. In contrast, LVS and the ΔfipB strain both prolonged the time to death, but there were no survivors from the challenge. This is the first demonstration of vaccine efficacy against aerosol challenge with virulent type A F. tularensis in a species other than a rodent since the original work with LVS in the 1960s. The ΔguaBA and ΔaroD SCHU S4 derivatives warrant further evaluation and consideration as potential vaccines for tularemia and for identification of immunological correlates of protection.

Transfer of learning between hands to handle a novel object in old age.

Transferring information about object weight between hands for use in scaling prehension forces likely depends on the integrity of the structures linking the two sides of the brain. It is unknown whether healthy older adults, who demonstrate a modest decline in this connectivity, transfer fingertip force scaling for object weight between hands. In the present study, healthy older and young adults performed two tasks: gripping and lifting an object, and a ballistic finger abduction movement. For the grip and lift task, participants practiced lifting a novel object using a precision pinch grip with the right hand (RH) and then did so again with the left hand (LH). For the ballistic task, participants were trained to maximally accelerate the right index finger by abducting it. On the grip and lift task, all participants appeared to overestimate the object weight during the 1st RH lift, followed by a progressive reduction on successive lifts. This adaptation was transferred to the LH in both groups on their first lift and remained stable over subsequent lifts. In contrast, the training-induced peak abduction acceleration on the ballistic task transferred poorly to the LH in older with considerably better transfer in young adults. We conclude that the memory representations scaling the lift force for the grip and lift task generalized to the untrained hand, while the greater acceleration that was acquired during practice of the ballistic task showed an incomplete transfer to the opposite hand. These differences may indicate task-dependent interhemispheric transfer of learning in old age.

Function-based gene identification using enzymatically generated normalized shRNA library and massive parallel sequencing.

As a general strategy for function-based gene identification, an shRNA library containing approximately 150 shRNAs per gene was enzymatically generated from normalized (reduced-redundance) human cDNA. The library was constructed in an inducible lentiviral vector, enabling propagation of growth-inhibiting shRNAs and controlled activity measurements. RNAi activities were measured for 101 shRNA clones representing 100 human genes and for 201 shRNAs derived from a firefly luciferase gene. Structure-activity analysis of these two datasets yielded a set of structural criteria for shRNA efficacy, increasing the frequencies of active shRNAs up to 5-fold relative to random sampling. The same library was used to select shRNAs that inhibit breast carcinoma cell growth by targeting potential oncogenes. Genes targeted by the selected shRNAs were enriched for 10 pathways, 9 of which have been previously associated with various cancers, cell cycle progression, or apoptosis. One hundred nineteen genes, enriched through this selection and represented by two to six shRNAs each, were identified as potential cancer drug targets. Short interfering RNAs against 19 of 22 tested genes in this group inhibited cell growth, validating the efficiency of this strategy for high-throughput target gene identification.

The effects of 72 h of dynamic ankle immobilization on neural excitability and lower extremity kinematics.

BACKGROUND: Ankle injuries can foster maladaptive changes in nervous system function that predisposes patients to subsequent injury. Patients are often placed in a dynamic boot immobilizer (BI) following injury; however, little is known about the effects of this treatment on neuromechanical function. RESEARCH QUESTION: We aimed to determine the effect of 72 h of BI-use on neural excitability and lower extremity joint motion in a healthy cohort. METHODS: Twelve uninjured individuals (20.8 ± 1.4 yrs, 1.7 ± 0.1 m, 75.2 ± 9.9 kg) participated in this crossover study. Neural excitability and lower extremity kinematics were assessed before and after 72 h of BI or compression sock (CS) use. Neural excitability was assessed via the Hoffmann (H) reflex and transcranial magnetic stimulation of the motor cortex by measuring muscle activation at the tibialis anterior, peroneus longus, and soleus of the immobilized extremity. Three-dimensional lower extremity joint angles were assessed while participants walked on a treadmill. Repeated-measures analyses of variance detected changes in neural excitability and peak joint angles across time-points and testing conditions, while statistical parametric mapping (SPM) was implemented to determine continuous joint angle changes (α = 0.05). RESULTS: Pre-BI to post-BI, HMax:MMax ratio (F = 6.496; p = 0.031) significantly decreased. The BI did not alter resting motor threshold (F = 0.601; p = 0.468), or motor evoked potential amplitudes (F > 2.82; p > 0.608). Significant changes in peak knee and hip angles in the frontal and transverse planes were observed (p < 0.05), with no changes at the ankle. SPM analyses revealed significant hip and knee changes in range of motion (p < 0.05). SIGNIFICANCE: Decreased measures of reflex but not corticospinal excitability suggest that BI-use for 72 h unloaded the joint enough to generate peripheral changes, but not the CNS, as has been described in casting models. Further, kinematic changes were observed in proximal lower extremity joints, likely due to swing-phase adaptations while wearing the BI.

Evidence of early B-cell dysregulation in simian immunodeficiency virus infection: rapid depletion of naïve and memory B-cell subsets with delayed reconstitution of the naïve B-cell population.

Despite eliciting a robust antibody response in humans, several studies in human immunodeficiency virus (HIV)-infected patients have demonstrated the presence of B-cell deficiencies during the chronic stage of infection. While several explanations for the HIV-induced B-cell deficit have been proposed, a clear mechanistic understanding of this loss of B-cell functionality is not known. This study utilizes simian immunodeficiency virus (SIV) infection of rhesus macaques to assess B-cell population dynamics beginning at the acute phase and continuing through the chronic phase of infection. Flow cytometric assessment demonstrated a significant early depletion of both naïve and memory B-cell subsets in the peripheral blood, with differential kinetics for recovery of these populations. Furthermore, the altered numbers of naïve and memory B-cell subsets in these animals corresponded with increased B-cell activation and altered proliferation profiles during the acute phase of infection. Finally, all animals produced high titers of antibody, demonstrating that the measurement of virus-specific antibody responses was not an accurate reflection of alterations in the B-cell compartment. These data indicate that dynamic B-cell population changes in SIV-infected macaques arise very early after infection at the precise time when an effective adaptive immune response is needed.

Nonpathogenic simian immunodeficiency virus infection of sooty mangabeys is not associated with high levels of autologous neutralizing antibodies.

Simian immunodeficiency virus (SIV) infection of natural-host species, such as sooty mangabeys (SMs), is characterized by a high level of viral replication and a low level of generalized immune activation, despite evidence of an adaptive immune response. Here the ability of SIV-infected SMs to mount neutralizing antibodies (Nab) against autologous virus was compared to that of human immunodeficiency virus type 1 (HIV-1) subtype C-infected subjects. While high levels of Nab were observed in HIV-1 infection, samples obtained at comparable time points from SM exhibited relatively low titers of autologous Nab. Nevertheless, SM plasma with higher Nab titers also contained elevated peripheral CD4(+) T-cell levels, suggesting a potential immunologic benefit for SMs. These data indicate that AIDS resistance in these primates is not due to high Nab titers and raise the possibility that low levels of Nab might be an inherent feature of natural-host SIV infections.

Slowing of dexterous manipulation in old age: force and kinematic findings from the 'nut-and-rod' task.

The task of sliding a nut from a rod has been used to study manual slowing in old age (Smith et al. in Neurology 53:1458-1461, 1999; Neurobiol Aging 26:883-890, 2005). In this experiment, we sought to determine if the age-related slowing in this task occurs with losses of motor precision, as indicated by the forces exerted on the rod. The forces exerted by the nut on the rod were monitored along with the kinematics of the hand in old and young adults while they attempted to lift a nut from three vertically oriented rods of different shape (straight, single curve, double curve). Old adults performed the task 64% slower than young adults for the straight rod, 100% slower for the single-curve rod, and 80% slower for the double-curve rod. Old adults did not differ from the young adults in the amount of force exerted against the rods in the horizontal plane, or in the steadiness of these forces, but exerted greater force impulses in the vertical direction over the course of a trial (359% straight, 236% single curve, 214% double curve) and much more force in the vertical direction (255% straight, 267% single curve, 159% double curve). Old adults also performed the task with 35% greater average roll of the hand into pronation. We suspect that old adults tilted the nut, even for the straight rod, dragging it against the rod to create the elevated vertical forces. These observations support previous speculation that old adults do not control the external moments applied to grasped objects as well as young adults.

Differential gene expression in peripheral blood mononuclear cells from children immunized with inactivated influenza vaccine.

The human immune response to inactivated influenza vaccine is dynamic and impacted by age and preexisting immunity. Our goal was to identify postvaccination transcriptomic changes in peripheral blood mononuclear cells from children. Blood samples were obtained before and at 3 or 7 days postvaccination with 2016-2017 quadrivalent inactivated influenza vaccine and RNA sequencing was performed. There were 1,466 differentially expressed genes (DEGs) for the Day 0-Day 3 group and 513 DEGs for the Day 0-Day 7 group. Thirty-three genes were common between the two groups. The majority of the transcriptomic changes at Day 3 represented innate inflammation and apoptosis pathways. Day 7 DEGs were characterized by activation of cellular processes, including the regulation of cytoskeleton, junctions, and metabolism, and increased expression of immunoglobulin genes. DEGs at Day 3 were compared between older and younger children revealing increased inflammatory gene expression in the older group. Vaccine history in the year prior to the study was characterized by robust DEGs at Day 3 with decreased phagosome and dendritic cell maturation in those who had been vaccinated in the previous year. PBMC responses to inactivated influenza vaccination in children differed significantly by the timing of sampling, patient age, and vaccine history. These data provide insight into the expected molecular pathways to be temporally altered by influenza vaccination in children.

Lifting a familiar object: visual size analysis, not memory for object weight, scales lift force.

The brain can accurately predict the forces needed to efficiently manipulate familiar objects in relation to mechanical properties such as weight. These predictions involve memory or some type of central representation, but visual analysis of size also yields accurate predictions of the needed fingertip forces. This raises the issue of which process (weight memory or visual size analysis) is used during everyday life when handling familiar objects. Our aim was to determine if subjects use a sensorimotor memory of weight, or a visual size analysis, to predictively set their vertical lift force when lifting a recently handled object. Two groups of subjects lifted an opaque brown bottle filled with water (470 g) during the first experimental session, and then rested for 15 min in a different room. Both groups were told that they would lift the same bottle in their next session. However, the experimental group returned to lift a slightly smaller bottle filled with water (360 g) that otherwise was identical in appearance to the first bottle. The control group returned to lift the same bottle from the first session, which was only partially filled with water so that it also weighed 360 g. At the end of the second session subjects were asked if they observed any changes between sessions, but no subject indicated awareness of a specific change. An acceleration ratio was computed by dividing the peak vertical acceleration during the first lift of the second session by the average peak acceleration of the last five lifts during the first session. This ratio was >1 for the control subjects 1.30 (SEM 0.08), indicating that they scaled their lift force for the first lift of the second session based on a memory of the (heavier) bottle from the first session. In contrast, the acceleration ratio was 0.94 (0.10) for the experimental group (P < 0.011). We conclude that the experimental group processed visual cues concerning the size of the bottle. These findings raise the possibility that even with familiar objects we predict fingertip forces using an on-line visual analysis of size (along with memory of density), rather than accessing memory related to object weight.

Failure to disrupt the 'sensorimotor' memory for lifting objects with a precision grip.

When repetitively lifting an object with mechanical properties that vary from lift-to-lift, the fingertip forces for gripping and lifting are influenced strongly by the previous lift, revealing a 'sensorimotor' memory. Two recent reports indicate that the sensorimotor memory for grip force is easily disrupted by an unrelated task like a strong pinch or vibration, even when the lift was performed with the hand contralateral to the vibration or preceding pinch. These findings indicate that this memory may reflect sensory input or muscle contraction levels, rather than object properties or the specific task of gripping and lifting. Here we report that the predictive scaling of lift force was not disrupted by conditioning tasks that featured exerting a vertical isometric force with the upper extremity. When subjects lifted a 2 N object repetitively the peak lift force rate was 26.4 N/s. The lift force rate increased to 36.1 N/s when the 2 N object was lifted (regardless of hand) after lifting the 8 N object with the right hand, which reveals the expected 'sensorimotor' memory. The lift force rate did not increase (24.8 vs. 26.4 N/s for the control condition) when a bout of isometric exertion (9.8 N) in the vertical direction with the distal right forearm preceded lifts of the 2 N object. This finding was confirmed with another isometric task designed to more closely mimic lifting an object with a precision grip. This difference in the sensitivity of grip versus lift force to a preceding isometric contraction indicates that separate sensorimotor memories contribute to the predictive scaling of the commands for gripping and lifting an object.

Inflammatory Mediator Expression Associated With Antibody Response Induced by Live Attenuated vs Inactivated Influenza Virus Vaccine in Children.

BACKGROUND: The reasons for differences in vaccine effectiveness between live attenuated influenza vaccine (LAIV) and inactivated influenza vaccine (IIV) are not clear. METHODS: Blood samples were obtained before vaccination and at days 7 and 21 postvaccination with 2015-2016 quadrivalent IIV or LAIV. Serologic response to the vaccine was measured by hemagglutination inhibition assay. Targeted RNA sequencing and serum cytokine analysis were performed. Paired analyses were used to determine gene expression and were compared between IIV and LAIV recipients. Classification And Regression Trees analysis (CART) identified the strongest associations with vaccine response. RESULTS: Forty-six enrollees received IIV, and 25 received LAIV. The mean age was 11.5 (±3.7) years. Seroconversion with IIV was associated with changes in expression of PRKRA and IFI6. Nonseroconversion for both IIV and LAIV was characterized by increased interferon-stimulated gene expression. Seroprotection with both vaccines was associated with altered expression of CXCL2 and CD36. For LAIV, CART showed that changes in expression of CD80, CXCL2, and CASP1 were associated with seroprotection. Serum cytokines showed that IIV seroconversion was associated with decreased CCL3. LAIV seroprotection tracked with decreased tumor necrosis factor-α and interferon-γ. CONCLUSIONS: Distinct markers of seroconversion and seroprotection against IIV and LAIV were identified using immunophenotyping and CART analysis.

Aerosol prime-boost vaccination provides strong protection in outbred rabbits against virulent type A Francisella tularensis.

Tularemia, also known as rabbit fever, is a severe zoonotic disease in humans caused by the gram-negative bacterium Francisella tularensis (Ft). While there have been a number of attempts to develop a vaccine for Ft, few candidates have advanced beyond experiments in inbred mice. We report here that a prime-boost strategy with aerosol delivery of recombinant live attenuated candidate Ft S4ΔaroD offers significant protection (83% survival) in an outbred animal model, New Zealand White rabbits, against aerosol challenge with 248 cfu (11 LD50) of virulent type A Ft SCHU S4. Surviving rabbits given two doses of the attenuated strains by aerosol did not exhibit substantial post-challenge fevers, changes in erythrocyte sedimentation rate or in complete blood counts. At a higher challenge dose (3,186 cfu; 139 LD50), protection was still good with 66% of S4ΔaroD-vaccinated rabbits surviving while 50% of S4ΔguaBA vaccinated rabbits also survived challenge. Pre-challenge plasma IgG titers against Ft SCHU S4 corresponded with survival time after challenge. Western blot analysis found that plasma antibody shifted from predominantly targeting Ft O-antigen after the prime vaccination to other antigens after the boost. These results demonstrate the superior protection conferred by a live attenuated derivative of virulent F. tularensis, particularly when given in an aerosol prime-boost regimen.

Differential gene expression elicited by children in response to the 2015-16 live attenuated versus inactivated influenza vaccine.

BACKGROUND: In recent influenza seasons, the live attenuated influenza vaccine (LAIV) has not demonstrated the same level of vaccine effectiveness as that observed among children who received the inactivated influenza vaccine (IIV). To better understand this difference, this study compared the mRNA sequencing transcription profile (RNA seq) in children who received either IIV or LAIV. METHODS: Children 3-17years of age receiving quadrivalent influenza vaccine were enrolled. Blood samples were collected on Day 0 prior to vaccination and again on Day 7 (range 6-10days) following vaccination. Total RNA was isolated from PAXgene tubes and sequenced for a custom panel of 89 transcripts using the TruSeq Targeted RNA Expression method. Fold differences in normalized RNA seq counts from Day 0 to Day 7 were calculated, log2 transformed and compared between the two vaccine groups. RESULTS: Of 72 children, 46 received IIV and 26 received LAIV. Following IIV vaccination, 7 genes demonstrated significant differential expression at Day 7 (down-regulated). In contrast, following LAIV vaccination, 8 genes demonstrated significant differential expression at Day 7 (5 up-regulated and 3 down-regulated). Only two genes demonstrated similar patterns of regulation in both groups. CONCLUSIONS: Differential regulation of genes was observed between 2015-16 LAIV and IIV recipients. These results help to elucidate the immune response to influenza vaccines and may be related to the difference in vaccine effectiveness observed in recent years between LAIV and IIV.