A Prospective Observational Study of Hypogammaglobulinemia in the First Year After Lung Transplantation.

BACKGROUND: Immunosuppressive therapies have led to improved survival for lung transplant (LT) recipients but these therapies can lead to hypogammaglobulinemia (HGG) and potentially an increased risk of infection. Large prospective studies have not been performed to evaluate the impact of HGG on outcomes for LT recipients. METHODS: This is a single-center prospective observational study of LT recipients. Pretransplant and posttransplant IgG levels were measured and related to infection, rejection, antibiotic use, and immunosuppression use. RESULTS: One hundred thirty-three LT recipients were prospectively evaluated. Pretransplant IgG values were higher than IgG values at the time of transplant or any time thereafter (all P < 0.0001). Severe HGG (IgG < 400 mg/dL) was highest at the time of transplant (32.4%) while at 3, 6, 9, and 12 months posttransplant the prevalence of severe HGG was 7.4%, 7.5%, 8.9%, and 6.3%, respectively. Severe HGG was associated with 2 or more pneumonias (P = 0.0006) and increased number of antibiotic courses (P = 0.003) compared with the subjects without severe HGG. Pretransplant IgG level and less than 30% of pretransplant protective pneumococcal antibody levels were identified as pretransplant risk factors for severe HGG. In multivariate analysis, chronic obstructive pulmonary disease as the underlying disease and the use of basiliximab as the induction agent in conjunction with higher prednisone and mycophenolate dosing were most predictive of severe HGG (P = 0.005), whereas the combination of age, severe HGG and number of acute steroid courses were most predictive of total days of pneumonia (P = 0.0001). CONCLUSIONS: Our large prospective study identifies risk factors for severe HGG after LT and demonstrates that LT recipients with severe HGG are at increased risk for recurrent pneumonias and more antibiotic courses.

A 10-year experience of a novel and safe modified environmental rush immunotherapy protocol.

BACKGROUND: Allergen immunotherapy (AIT) is an effective treatment option for allergic rhinitis. Although conventional AIT takes 6 months to reach maintenance dosing, rush AIT accelerates the build-up period and reaches the maintenance dose months earlier. However, accelerated schedules of AIT carry an increased risk of systemic reactions (SR). OBJECTIVE: We aimed to describe a novel 1-day, eight-step modified environmental rush immunotherapy (MERIT) protocol, characteristics of the patients who underwent this therapy, and the safety of this procedure. We also compared distinguishing features of those patients with SRs. METHODS: We retrospectively analyzed demographic and clinical data of 362 adult patients seen in an outpatient university allergy clinic, from January 2005 to January 2015, and who underwent MERIT protocol treatment for allergic rhinitis. RESULTS: In a univariate analysis, the factors significantly associated with SR were lower body mass index (BMI); younger age; a higher number of allergens in the extracts; and the presence of cat, dust mite, and certain weed pollens. In a multivariate analysis, cat, dust mite, and mugwort were significantly associated with SRs. Over the 10-year period, 50 patients experienced SRs (13.81%), with a total number of 68 SRs. Only 4.7% of the SRs occurred on the MERIT day. Most SRs occurred >30 minutes and were mild. Our MERIT protocol continuation rate for all the patients was 49.2% and did not seem to be influenced by having an SR versus no SR. CONCLUSION: We present a modified rush AIT protocol that seems to be effective and safe. Most patients tolerated therapy, and only a minority of patients developed SRs, which generally were mild. We identified novel risk factors for SRs that may help determine optimal dosing to decrease the risk of SRs. Ultimately, future studies will be needed to compare the safety of our MERIT protocol with traditional AIT.

The morbidity and cost of vocal cord dysfunction misdiagnosed as asthma.

BACKGROUND: Vocal cord dysfunction (VCD) is frequently misdiagnosed and mistreated as asthma, which leads to morbidity secondary to unnecessary medication use and increased health care utilization. OBJECTIVE: We identified discriminating symptoms and triggers, and analyzed the costs, morbidity, and health care burden associated with misdiagnosis of VCD as asthma. We sought to determine if current measures of asthma control contributed to these findings. We evaluated if a simple set of breathing exercises would be an effective low-cost treatment option for those with VCD. METHODS: We compared the demographics, comorbidities, clinical symptoms, and symptom triggers of subjects with VCD misdiagnosed as asthma compared with those not misdiagnosed as asthma. Costs secondary to asthma misdiagnosis were quantified, and the effectiveness of breathing exercises as a treatment option was evaluated. RESULTS: We identified symptoms of shortness of breath, wheezing, chest tightness, and a trigger of exercise as being more common in the subjects with VCD misdiagnosed as asthma. Asthma medication use and health care utilization and costs were also higher in this group. The subjects with VCD had Asthma Control Questionnaire scores that labelled them as having uncontrolled asthma. Breathing exercises appeared to offer an inexpensive and effective treatment option for subjects with VCD. CONCLUSION: Misdiagnosis of VCD as asthma leads to significant morbidity and increased costs, and misuse of measures of asthma control may be contributing to these findings. Timely and accurate diagnosis of VCD and the use of breathing exercises have the potential to eliminate or minimize the burdens on the patient and the health care system.

Phenotypic and genotypic association of epithelial IL1RL1 to human TH2-like asthma.

BACKGROUND: Severe asthma remains poorly characterized, although it likely consists of at least 1 phenotype with features of TH2-like inflammation. IL1RL1, encoding both the IL-33 receptor, ST2L, and decoy receptor, sST2, has been genetically associated with asthma, though the mechanism for susceptibility remains unknown. OBJECTIVE: Given previous data supporting a role for IL1RL1 in TH2 inflammation, we hypothesized that ST2L expression might be increased in TH2-like asthma and that expression levels would be associated with single nucleotide polymorphisms in IL1RL1, possibly explaining its genetic relationship with asthma. We also sought to evaluate the regulation of ST2L and sST2 in vitro. METHODS: Endobronchial brushings and biopsies were obtained and expression of ST2L compared by severity levels, as well as by TH2-like biomarkers. Subjects were genotyped and the relationship of dichotomous expression of ST2L and sST2 to single nucleotide polymorphisms in IL1RL1 were determined. Epithelial cells were grown in air-liquid interface culture, and ST2L and sST2 responses to IFN-γ and IL-13 were evaluated. RESULTS: ST2L expression was increased in severe asthma (P = .02) and associated with multiple indicators of TH2-like inflammation, including blood eosinophils (P = .001), exhaled nitric oxide (P = .003), and epithelial CLCA1 (P < .0001) and eotaxin-3 (P = .001) mRNA expression. Multiple single nucleotide polymorphisms in IL1RL1 were found in relation to dichotomous expression of both ST2L and sST2. sST2 expression was associated with IFN-γ expression in bronchoalveolar lavage, while inducing its expression in vitro in primary human epithelial cells. CONCLUSION: Both pathologic and genetic approaches support a role for IL1RL1 in severe asthma, as well as TH2-lke asthma, suggesting that targeting this pathway may have therapeutic benefits.

Focal adhesion kinase-mediated activation of glycogen synthase kinase 3ß regulates IL-33 receptor internalization and IL-33 signaling.

IL-33, a relatively new member of the IL-1 cytokine family, plays a crucial role in allergic inflammation and acute lung injury. Long form ST2 (ST2L), the receptor for IL-33, is expressed on immune effector cells and lung epithelia and plays a critical role in triggering inflammation. We have previously shown that ST2L stability is regulated by the ubiquitin-proteasome system; however, its upstream internalization has not been studied. In this study, we demonstrate that glycogen synthase kinase 3ß (GSK3ß) regulates ST2L internalization and IL-33 signaling. IL-33 treatment induced ST2L internalization, and an effect was attenuated by inhibition or downregulation of GSK3ß. GSK3ß was found to interact with ST2L on serine residue 446 in response to IL-33 treatment. GSK3ß binding site mutant (ST2L(S446A)) and phosphorylation site mutant (ST2L(S442A)) are resistant to IL-33-induced ST2L internalization. We also found that IL-33 activated focal adhesion kinase (FAK). Inhibition of FAK impaired IL-33-induced GSK3ß activation and ST2L internalization. Furthermore, inhibition of ST2L internalization enhanced IL-33-induced cytokine release in lung epithelial cells. These results suggest that modulation of the ST2L internalization by FAK/GSK3ß might serve as a unique strategy to lessen pulmonary inflammation.

A novel scoring system to distinguish vocal cord dysfunction from asthma.

BACKGROUND: Vocal cord dysfunction is often misdiagnosed and mistreated as asthma, which can lead to increased and unnecessary medication use and increased health care utilization. OBJECTIVE: To develop a valid scoring index that could help distinguish vocal cord dysfunction from asthma. METHODS: We compared the demographics, comorbidities, clinical symptoms, and symptom triggers of subjects with vocal cord dysfunction (n = 89) and those with asthma (n = 59). By using multivariable logistic regression, we identified distinguishing features associated with vocal cord dysfunction, which were weighted and used to generate a novel score. The scoring index also was tested in an independent sample with documented vocal cord dysfunction (n = 72). RESULTS: We identified symptoms of throat tightness and dysphonia, the absence of wheezing, and the presence of odors as a symptom trigger as key features of vocal cord dysfunction that distinguish it from asthma. We developed a weighted index based on these characteristics, the Pittsburgh Vocal Cord Dysfunction Index. By using a cutoff of ≥4, this index had good sensitivity (0.83) and specificity (0.95) for the diagnosis of vocal cord dysfunction. The scoring index also performed reasonably well in the independent convenience sample with laryngoscopy-proven vocal cord dysfunction and accurately made the diagnosis in 77.8% of subjects. CONCLUSION: The Pittsburgh Vocal Cord Dysfunction Index is proposed as a simple, valid, and easy-to-use tool for diagnosing vocal cord dysfunction. If confirmed by a prospective evaluation in broader use, it may have significant clinical utility by facilitating a timely and accurate diagnosis of vocal cord dysfunction, thereby preventing misdiagnosis and mistreatment as asthma. Future prospective validation studies will need to be performed.

A retrospective analysis comparing subjects with isolated and coexistent vocal cord dysfunction and asthma.

Vocal cord dysfunction (VCD) is often misdiagnosed as asthma or complicates coexisting asthma. This study aimed to identify distinguishing clinical characteristics in patients with VCD, asthma, and coexisting VCD and asthma. We conducted a retrospective analysis of demographic and clinical data from 292 patients with VCD, asthma, coexisting VCD and asthma, and control subjects from an outpatient university asthma/allergy clinic. Concomitant asthma was present in 32.6% of VCD subjects. Overall, 42.4 % of all VCD subjects were previously misdiagnosed as having asthma for an average of 9.0 years. Upper airway symptoms were more prevalent in the VCD population and nocturnal apnea was more prevalent in comorbid VCD and asthma compared with either condition alone. Irritable bowel syndrome and chronic pain were identified as new comorbidities associated with VCD. VCD subjects who had been misdiagnosed with asthma had significantly more health care and asthma medication use compared to VCD subjects who had not mimicked asthma. There was no difference in asthma severity between those with and without VCD. Comorbid VCD and asthma led to an increase in long-acting ß-agonist use only, but no difference in health care usage, compared with asthma alone. These findings suggest that the main morbidity associated with VCD may not lie in its inherent disease process, but instead in its ability to mimic asthma.

Whole-exome sequencing identifies tetratricopeptide repeat domain 7A (TTC7A) mutations for combined immunodeficiency with intestinal atresias.

BACKGROUND: Combined immunodeficiency with multiple intestinal atresias (CID-MIA) is a rare hereditary disease characterized by intestinal obstructions and profound immune defects. OBJECTIVE: We sought to determine the underlying genetic causes of CID-MIA by analyzing the exomic sequences of 5 patients and their healthy direct relatives from 5 unrelated families. METHODS: We performed whole-exome sequencing on 5 patients with CID-MIA and 10 healthy direct family members belonging to 5 unrelated families with CID-MIA. We also performed targeted Sanger sequencing for the candidate gene tetratricopeptide repeat domain 7A (TTC7A) on 3 additional patients with CID-MIA. RESULTS: Through analysis and comparison of the exomic sequence of the subjects from these 5 families, we identified biallelic damaging mutations in the TTC7A gene, for a total of 7 distinct mutations. Targeted TTC7A gene sequencing in 3 additional unrelated patients with CID-MIA revealed biallelic deleterious mutations in 2 of them, as well as an aberrant splice product in the third patient. Staining of normal thymus showed that the TTC7A protein is expressed in thymic epithelial cells, as well as in thymocytes. Moreover, severe lymphoid depletion was observed in the thymus and peripheral lymphoid tissues from 2 patients with CID-MIA. CONCLUSIONS: We identified deleterious mutations of the TTC7A gene in 8 unrelated patients with CID-MIA and demonstrated that the TTC7A protein is expressed in the thymus. Our results strongly suggest that TTC7A gene defects cause CID-MIA.

Unique N-linked glycosylation of CasBrE Env influences its stability, processing, and viral infectivity but not its neurotoxicity.

The envelope protein (Env) from the CasBrE murine leukemia virus (MLV) can cause acute spongiform neurodegeneration analogous to that induced by prions. Upon central nervous system (CNS) infection, Env is expressed as multiple isoforms owing to differential asparagine (N)-linked glycosylation. Because N-glycosylation can affect protein folding, stability, and quality control, we explored whether unique CasBrE Env glycosylation features could influence neurovirulence. CasBrE Env possesses 6/8 consensus MLV glycosylation sites (gs) but is missing gs3 and gs5 and contains a putative site (gs*). Twenty-nine mutants were generated by modifying these three sites, individually or in combination, to mimic the amino acid sequence in the nonneurovirulent Friend 57 MLV. Three basic viral phenotypes were observed: replication defective (dead; titer < 1 focus-forming unit [FFU]/ml), replication compromised (RC) (titer = 10(2) to 10(5) FFU/ml); and wild-type-like (WTL) (titer > 10(5) FFU/ml). Env protein was undetectable in dead mutants, while RC and WTL mutants showed variations in Env expression, processing, virus incorporation, virus entry, and virus spread. The newly introduced gs3 and gs5 sites were glycosylated, whereas gs* was not. Six WTL mutants tested in mice showed no clear attenuation in disease onset or severity versus controls. Furthermore, three RC viruses tested by neural stem cell (NSC)-mediated brainstem dissemination also induced acute spongiosis. Thus, while unique N-glycosylation affected structural features of Env involved in protein stability, proteolytic processing, and virus assembly and entry, these changes had minimal impact on CasBrE Env neurotoxicity. These findings suggest that the Env protein domains responsible for spongiogenesis represent highly stable elements upon which the more variable viral functional domains have evolved.

Community opinions regarding oral immunotherapy for food allergies.

BACKGROUND: Food oral immunotherapy (OIT) is a promising but still investigational new therapy for food allergy. OBJECTIVE: We sought to investigate beliefs and opinions among OIT participants and nonparticipants to better understand community awareness of this therapy. METHODS: A 30-question on-line survey was administered to members, website visitors, and social media followers of the Kids with Food Allergy Foundation. Questions inquired about general knowledge and attitudes about OIT, its reported safety and efficacy, complications, insurance coverage, and its Food and Drug Administration (FDA) approval status. RESULTS: Among 1,274 survey respondents, 15.9% had discussed OIT as a treatment option with their allergy provider. Five percent (n = 64) of respondents reported that their child was currently participating in OIT, including 73.4% (n = 47) in a private practice setting. Participants reported varying degrees of being informed about OIT safety (85%), efficacy (46.4% told unrestricted ingestion), risks (relapse 53.4%, eosinophilic esophagitis 3.5%, oral allergy syndrome 10.7%, and failure 56.9%). Significantly fewer participants than nonparticipants agreed that OIT's present safety, efficacy, risks, and approval status would dissuade participation. Significantly fewer participants agreed that OIT should not be offered outside the research setting without definitive proof of both its safety and efficacy. CONCLUSION: In this exploratory study, differences in beliefs and opinions existed between OIT participants and nonparticipants. Among participants, there were also significant differences in beliefs among academic versus nonacademic participants. Accurate and complete information about OIT safety, efficacy, risks, and approval status was not universally conveyed.

Retrovirus-induced spongiform neurodegeneration is mediated by unique central nervous system viral targeting and expression of env alone.

Certain murine leukemia viruses (MLVs) can induce progressive noninflammatory spongiform neurodegeneration similar to that caused by prions. The primary MLV determinants responsible have been mapped to within the env gene; however, it has remained unclear how env mediates disease, whether non-Env viral components are required, and what central nervous system (CNS) cells constitute the critical CNS targets. To address these questions, we examined the effect of transplanting engraftable C17.2 neural stem cells engineered to pseudotype, disseminate, and trans-complement neurovirulent (CasBrE, CasE, and CasES) or non-neurovirulent (Friend and SFF-FE) env sequences (SU or SU/TM) within the CNS using either the "non-neurovirulent" amphotropic helper virus, 4070A, or pgag-polgpt (a nonpackaged vector encoding Gag-Pol). These studies revealed that acute MLV-induced spongiosis results from two separable activities of Env. First, Env causes neuropathology through unique viral targeting within the CNS, which was efficiently mediated by ecotropic Envs (CasBrE and Friend), but not 4070A amphotropic Env. Second, Env induces spongiosis through a toxin activity that is MLV-receptor independent and does not require the coexpression of other viral structural proteins. CasBrE and 4070A Envs possess the toxin activity, whereas Friend Env does not. Although the identity of the critical viral target cell(s) remains unresolved, our results appear to exclude microglia and oligodendrocyte lineage cells, while implicating viral entry into susceptible neurons. Thus, MLV-induced disease parallels prionopathies in that a single protein, Env, mediates both the CNS targeting and the toxicity of the infectious agent that manifests itself as progressive vacuolar neurodegeneration.

Gene therapy for arthritis.

Arthritis is among the leading causes of disability in the developed world. There remains no cure for this disease and the current treatments are only modestly effective at slowing the disease's progression and providing symptomatic relief. The clinical effectiveness of current treatment regimens has been limited by short half-lives of the drugs and the requirement for repeated systemic administration. Utilizing gene transfer approaches for the treatment of arthritis may overcome some of the obstacles associated with current treatment strategies. The present review examines recent developments in gene therapy for arthritis. Delivery strategies, gene transfer vectors, candidate genes, and safety are also discussed.

Inflammatory cytokine regulation of transgene expression in human fibroblast-like synoviocytes infected with adeno-associated virus.

OBJECTIVE: An ideal gene transfer vector for chronic inflammatory diseases such as rheumatoid arthritis (RA) would provide local transgene expression only when the disease is active. To determine whether adeno-associated virus (AAV) possesses this ability, the effects of inflammatory cytokines on transgene expression were evaluated in human RA fibroblast-like synoviocytes (FLS). METHODS: Human FLS were infected with AAV in the presence or absence of inflammatory cytokines or synovial fluid obtained from patients with RA. Transgene expression was monitored by either enzyme-linked immunosorbent assay or flow cytometry. Transgene messenger RNA (mRNA) was measured by real-time quantitative reverse transcription-polymerase chain reaction. RESULTS: Inflammatory cytokines increased transgene expression in FLS by up to 60-fold. Synovial fluid from patients with RA, but not from patients without arthritis, was also able to increase expression in synoviocytes. Protein expression correlated with transgene mRNA levels. The enhanced expression required the continued presence of cytokines because, upon removal, transgene expression returned to baseline levels. Expression could be repeatedly reinduced by reexposure to cytokines. The effect was not promoter specific and was demonstrated to be phosphatidylinositol 3-kinase-dependent. CONCLUSION: These results suggest that expression of a therapeutic transgene can be controlled by the presence of inflammation following AAV gene transfer, making it an attractive vector for chronic inflammatory diseases such as RA.

Reexamination of amphotropic murine leukemia virus neurovirulence: neural stem cell-mediated microglial infection fails to induce acute neurodegeneration.

The 4070A amphotropic murine leukemia virus (A-MuLV) has been variably reported to harbor neurovirulence determinants within its env gene. In this report we reexamined this issue by applying two approaches previously demonstrated to amplify murine leukemia virus neurovirulence. The first approach involved introducing the 4070A env gene into the background of Friend virus clone FB29 to enhance peripheral virus replication kinetics and central nervous system entry. The resulting chimeric virus, FrAmE, exhibited widespread vascular infection throughout the central nervous system (CNS); however, parenchymal infection was quite limited. Neither clinical neurological signs nor spongiform neurological changes accompanied FrAmE CNS infection. To overcome this CNS entry limitation, 4070A and FrAmE were delivered directly into the CNS via transplantation of infected C17.2 neural stem cells (NSCs). Significantly, NSC dissemination of either 4070A or FrAmE resulted in widespread, high-level amphotropic virus expression within the CNS parenchyma, including the infection of microglia, the critical target required for inducing neurodegeneration. Despite the extensive CNS infection, no associated clinical neurological signs or acute neuropathological changes were observed. Interestingly, we observed the frequent appearance of circulating polytropic (MCF) virus in the serum of amphotropic virus-infected animals. However, neither peripheral inoculation of an amphotropic/MCF virus mixture nor transplantation of NSCs expressing both amphotropic and MCF viruses induced acute clinical neurological signs or spongiform neuropathology. Thus, the results generated in this study suggest that the 4070A env gene is not inherently neurovirulent. However, the frequent appearance of endogenous MCF viruses suggests the possibility that the interactions of amphotropic viruses with endogenous retroviral elements could contribute to the development of retrovirus-induced neurodegenerative disease.