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1.
Nat Immunol ; 23(3): 380-385, 2022 03.
Article in English | MEDLINE | ID: mdl-35115679

ABSTRACT

Delayed dosing intervals are a strategy to immunize a greater proportion of the population. In an observational study, we compared humoral and cellular responses in health care workers receiving two doses of BNT162b2 (Pfizer-BioNTech) vaccine at standard (3- to 6-week) and delayed (8- to 16-week) intervals. In the delayed-interval group, anti-receptor-binding domain antibody titers were significantly enhanced compared to the standard-interval group. The 50% plaque reduction neutralization test (PRNT50) and PRNT90 titers against wild-type (ancestral) severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) and Alpha, Beta and Delta variants were higher in the delayed-interval group. Spike-specific polyfunctional CD4+ and CD8+ T cells expressing interferon-γ and interleukin-2 were comparable between the two groups. Here, we show that the strategy of delaying second doses of mRNA vaccination may lead to enhanced humoral immune responses, including improved virus neutralization against wild-type and variant SARS-CoV-2 viruses. This finding has potentially important implications as vaccine implementation continues across a greater proportion of the global population.


Subject(s)
BNT162 Vaccine/immunology , CD4-Positive T-Lymphocytes/immunology , CD8-Positive T-Lymphocytes/immunology , COVID-19/immunology , SARS-CoV-2/physiology , Adult , Cells, Cultured , Female , Humans , Immunity, Humoral , Immunization, Secondary , Interferon-gamma/metabolism , Interleukin-2/metabolism , Male , Middle Aged , Vaccination , Vaccination Hesitancy
2.
Anal Chem ; 96(10): 3994-3998, 2024 Mar 12.
Article in English | MEDLINE | ID: mdl-38349767

ABSTRACT

Analytical chemistry has never yielded such a wealth of experimental data as it does today, and this exponential trend shows no sign of abating. We continually advance the capabilities of our instruments and conceive innovative concepts, all in a concerted effort to naturally push the boundaries of our understanding regarding intricate sample matrices. Spectroscopic imaging, in the broadest sense, is certainly the field where we observe this acceleration even more pronouncedly. Analytical chemistry swiftly grasped the significance of processing acquired data for comprehensive exploration through utilization of chemometrics or machine learning tools. One can assert today that chemometrics undeniably constitutes an integral facet in the advancement of an analytical approach. However, we are now faced with a new challenge, as the experimental data accumulated for certain analytical techniques are so vast and massive that exploring them with such tools has become unfeasible, and this is by no means a computational capacity issue. Analytical chemistry is far from being the sole field affected by this issue, and one could argue that others have grappled with it long before us, such as, for instance, social media, to name just one. The purpose of this paper is to demonstrate that such a domain, which may initially seem distant from our concerns, can offer novel tools capable of overcoming these barriers, even though we are not necessarily dealing with the same objects. More specifically, we delve into the clustering of over 10 million LIBS spectra acquired as part of an imaging experiment aimed at exploring a singular rock sample. This will serve to demonstrate that an open-source library developed by Meta (formerly known as Facebook) can enable us to conduct a comprehensive exploration of this sample, a feat deemed impossible with conventional data analysis approaches.

3.
Anal Chem ; 96(18): 7038-7046, 2024 May 07.
Article in English | MEDLINE | ID: mdl-38575850

ABSTRACT

Laser-induced breakdown spectroscopy (LIBS) imaging continues to gain strength as an influential bioanalytical technique, showing intriguing potential in the field of clinical analysis. This is because hyperspectral LIBS imaging allows for rapid, comprehensive elemental analysis, covering elements from major to trace levels consistently year after year. In this study, we estimated the potential of a multivariate spectral data treatment approach based on a so-called convex envelope method to detect exotic elements (whether they are minor or in trace amounts) in biopsy tissues of patients with occupational exposure-related diseases. More precisely, we have developed an approach called Interesting Features Finder (IFF), which initially allowed us to identify unexpected elements without any preconceptions, considering only the set of spectra contained in a LIBS hyperspectral data cube. This task is, in fact, almost impossible with conventional chemometric tools, as it entails identifying a few exotic spectra among several hundred thousand others. Once this detection was performed, a second approach based on correlation was used to locate their distribution in the biopsies. Through this unique data analysis pipeline to processing massive LIBS spectroscopic data, it was possible to detect and locate exotic elements such as tin and rhodium in a patient's tissue section, ultimately leading to a possible reclassification of their lung condition as an occupational disease. This review will thus demonstrate the potential of this new diagnostic tool based on LIBS imaging in addressing the shortcomings of approaches developed thus far. The proposed data processing approach naturally transcends this specific framework and can be leveraged across various domains of analytical chemistry, where the detection of rare events is concealed within extensive data sets.


Subject(s)
Lung Diseases , Humans , Biopsy , Lung Diseases/diagnosis , Lung Diseases/pathology , Occupational Diseases/diagnosis , Occupational Diseases/pathology , Lasers , Spectrum Analysis/methods , Lung/pathology , Lung/chemistry , Lung/diagnostic imaging
4.
Clin Infect Dis ; 77(2): 229-236, 2023 07 26.
Article in English | MEDLINE | ID: mdl-36975097

ABSTRACT

BACKGROUND: In solid organ transplant (SOT) recipients, the primary vaccination series against Coronavirus Disease 2019 is 3 doses followed by boosters. We determined whether a fourth dose booster induced Omicron BA.4/5 neutralizing antibodies (nAbs) and T cells in a large multicenter cohort study. METHODS: Serum was collected 4-6 weeks post-third and post-fourth doses of messenger RNA vaccine in 222 SOT recipients. nAbs were measured using a pseudovirus neutralization assay that targeted the Omicron BA.4/5 spike protein. A subset underwent T-cell testing. RESULTS: The median age of the cohort was 63 years (interquartile range [IQR], 50-68) with 61.7% men. BA.4/5 nAb detection increased from 26.6% (59 of 222) post-third dose to 53.6% (119 of 222) post-fourth dose (P < .0001). In patients with breakthrough infection prior to the fourth dose (n = 27), nAbs were detected in 77.8% and median nAb titers were significantly higher compared with those with 4 vaccine doses alone (P < .0001). Factors associated with a low BA.4/5 neutralization response after the fourth dose were older age (odds ratio [OR], 0.96; 95% confidence interval [CI], .94-.99), mycophenolate use (OR, 0.39; 95% CI, .20-.77) and prednisone use (OR, 0.34; 95% CI, .18-.63), and vaccine type (OR, 0.72; 95% CI, .51-.99), while breakthrough infection prior to the fourth dose (OR, 3.6; 95% CI, 1.3-9.9) was associated with a greater nAb response. Polyfunctional BA.4/5-specific CD4+ T cells significantly increased after 4 doses and were identified in 76.9% of patients at a median frequency of 213/106 cells (IQR, 98-650). CONCLUSIONS: In summary, a booster significantly increases BA.4/5-specific neutralization and polyfunctional CD4+ T-cell responses, suggesting protection from severe disease even with new Omicron variants. However, SOT recipients who are older and on mycophenolate and prednisone need additional preventative strategies.


Subject(s)
COVID-19 , Organ Transplantation , Male , Humans , Middle Aged , Female , Cohort Studies , Prednisone , SARS-CoV-2 , Antibodies, Neutralizing , Breakthrough Infections , Immunosuppressive Agents/therapeutic use , RNA, Messenger , Transplant Recipients , mRNA Vaccines , Antibodies, Viral
5.
Am J Transplant ; 23(2): 278-283, 2023 02.
Article in English | MEDLINE | ID: mdl-36744606

ABSTRACT

Mutations in the spike protein of SARS-CoV-2 have allowed Omicron subvariants to escape neutralizing antibodies. The degree to which this occurs in transplant recipients is poorly understood. We measured BA.4/5 cross-neutralizing responses in 75 mostly vaccinated transplant recipients who recovered from BA.1 infection. Sera were collected at 1 and 6 months post-BA.1 infection, and a lentivirus pseudovirus neutralization assay was performed using spike constructs corresponding to BA.1 and BA.4/5. Uninfected immunized transplant recipients and health care worker controls were used for comparison. Following BA.1 infection, the proportion of transplant recipients with neutralizing antibody responses was 88.0% (66/75) against BA.1 and 69.3% (52/75) against BA.4/5 (P = .005). The neutralization level against BA.4/5 was approximately 17-fold lower than that against BA.1 (IQR 10.6- to 45.1-fold lower, P < .0001). BA.4/5 responses declined over time and by ≥0.5 log10 (approximately 3-fold) in almost half of the patients by 6 months. BA.4/5-neutralizing antibody titers in transplant recipients with breakthrough BA.1 infection were similar to those in immunized health care workers but significantly lower than those in uninfected triple-vaccinated transplant recipients. These results provide evidence that transplant recipients are at ongoing risk for BA.4/5 infection despite vaccination and prior Omicron strain infection, and additional mitigation strategies may be required to prevent severe disease in this cohort.


Subject(s)
COVID-19 , Humans , COVID-19/epidemiology , SARS-CoV-2 , Transplant Recipients , Antibodies, Neutralizing , Biological Assay , Breakthrough Infections , Antibodies, Viral
6.
Ann Intern Med ; 175(2): 226-233, 2022 02.
Article in English | MEDLINE | ID: mdl-34807716

ABSTRACT

BACKGROUND: COVID-19 is more severe in transplant recipients. Variants of concern have supplanted wild-type virus. In transplant recipients, data are limited on 2-dose or 3-dose vaccine immunogenicity against variant viruses. OBJECTIVE: To assess neutralizing antibody responses against SARS-CoV-2 variants in transplant recipients after 2 and 3 vaccine doses. DESIGN: Secondary analysis of a randomized, double-blind, controlled trial of a third dose of mRNA-1273 vaccine versus placebo. (ClinicalTrials.gov: NCT04885907). SETTING: Single-center transplant program. PATIENTS: Organ transplant recipients. INTERVENTION: Third dose of mRNA-1273 vaccine versus placebo. MEASUREMENTS: Sera were analyzed for neutralization against wild-type virus and the Alpha, Beta, and Delta variants using a surrogate virus neutralization assay and a spike-pseudotyped lentivirus assay. RESULTS: A total of 117 transplant recipients were analyzed (60 in the mRNA-1273 group and 57 in the placebo group). Sera were obtained before and 4 to 6 weeks after the third dose. After 2 doses, the proportion of patients with positive neutralization for all 3 variants was small compared with wild-type virus. After the third dose of mRNA-1273 vaccine, the proportion with a positive neutralization response versus placebo was improved for all 3 variants as measured by both assays. Based on the pseudovirus neutralization assay against the Delta variant, 33 of 60 (55%) patients were positive in the mRNA-1273 group versus 10 of 57 (18%) in the placebo group (difference, 37 [95% CI, 19 to 53] percentage points). The differences were 36 (CI, 17 to 51) percentage points for the Alpha variant and 31 (CI, 15 to 46) percentage points for the Beta variant. In the mRNA-1273 group, lower neutralization values were observed for variants compared with wild-type virus, especially the Beta variant. LIMITATIONS: There is no clear correlate of protection for neutralizing antibody. This was a secondary analysis. CONCLUSION: In organ transplant recipients, a third dose of mRNA vaccine increases neutralizing antibody response against SARS-CoV-2 variants compared with placebo. PRIMARY FUNDING SOURCE: Ajmera Transplant Centre.


Subject(s)
2019-nCoV Vaccine mRNA-1273/administration & dosage , Antibodies, Neutralizing/blood , COVID-19/immunology , COVID-19/prevention & control , Organ Transplantation , SARS-CoV-2 , Transplant Recipients , 2019-nCoV Vaccine mRNA-1273/adverse effects , Aged , COVID-19/virology , Double-Blind Method , Female , Humans , Immunocompromised Host , Male , Middle Aged
7.
Am J Transplant ; 22(8): 2089-2093, 2022 08.
Article in English | MEDLINE | ID: mdl-35266606

ABSTRACT

The SARS-CoV-2 virus Omicron variant has now supplanted wild-type virus as the dominant circulating strain globally. Three doses of mRNA COVID-19 vaccine are recommended for transplant recipients as their primary vaccine series. However, the immunogenicity of mRNA vaccines as they specifically relate to the Omicron variant are not well studied. We analyzed Omicron-specific neutralization in transplant recipients after three-doses of mRNA-1273 vaccine. Neutralization was determined using a SARS-CoV-2 spike pseudotyped lentivirus assay with constructs for Omicron and Delta variants. A total of 60 transplant patients (kidney, kidney-pancreas, lung, heart, liver) were analyzed 1 month and 3 months after completion of three doses of mRNA-1273. At 1 month, 11/60 (18.3%) patients had detectable neutralizing antibody responses to Omicron (log10 ID50 of 2.38 [range 1.34-3.57]). At 3 months, 8/51 (15.7%) were positive (median log10 ID50 [1.68; range 1.12-3.61; approximate fivefold reduction over time]). The proportion of positive patients was lower for Omicron versus wild-type, and Omicron vs. Delta (p < .001). No demographic variables were found to be significantly associated with Omicron response. Many patients with a positive anti-RBD response still had undetectable Omicron-specific neutralizing antibody. In conclusion, three doses of mRNA vaccine results in poor neutralizing responses against the Omicron variant in transplant patients.


Subject(s)
2019-nCoV Vaccine mRNA-1273 , COVID-19 , Transplant Recipients , 2019-nCoV Vaccine mRNA-1273/immunology , Antibodies, Neutralizing , Antibodies, Viral , COVID-19/prevention & control , Humans , Neutralization Tests , SARS-CoV-2 , Spike Glycoprotein, Coronavirus
8.
J Infect Dis ; 224(11): 1849-1860, 2021 12 01.
Article in English | MEDLINE | ID: mdl-34739078

ABSTRACT

T-cell immunity associated with severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection or vaccination in solid organ transplant recipients (SOTRs) is poorly understood. To address this, we measured T-cell responses in 50 SOTRs with prior SARS-CoV-2 infection. The majority of patients mounted SARS-CoV-2-specific CD4+ T-cell responses against spike (S), nucleocapsid, and membrane proteins; CD8+ T-cell responses were generated to a lesser extent. CD4+ T-cell responses correlated with antibody levels. Severity of disease and mycophenolate dose were moderately associated with lower proportions of antigen-specific T cells. Relative to nontransplant controls, SOTRs had perturbations in both total and antigen-specific T cells, including higher frequencies of total PD-1+ CD4+ T cells. Vaccinated SOTRs (n = 55) mounted significantly lower proportions of S-specific polyfunctional CD4+ T cells after 2 doses, relative to unvaccinated SOTRs with prior coronavirus disease 2019. Together, these results suggest that SOTRs generate robust T-cell responses following natural infection that correlate with disease severity but generate comparatively lower T-cell responses following mRNA vaccination.


Subject(s)
COVID-19 Vaccines/immunology , COVID-19/immunology , T-Lymphocytes/immunology , Transplant Recipients , Humans , Immunity, Cellular , Organ Transplantation , SARS-CoV-2 , Vaccination
9.
Am J Transplant ; 21(12): 3980-3989, 2021 12.
Article in English | MEDLINE | ID: mdl-34347934

ABSTRACT

Solid organ transplant recipients are at high risk of severe disease from COVID-19. We assessed the immunogenicity of mRNA-1273 vaccine using a combination of antibody testing, surrogate neutralization assays, and T cell assays. Patients were immunized with two doses of vaccine and immunogenicity assessed after each dose using the above tests. CD4+ and CD8+ T cell responses were assessed in a subset using flow-cytometry. A total of 127 patients were enrolled of which 110 provided serum at all time points. A positive anti-RBD antibody was seen in 5.0% after one dose and 34.5% after two doses. Neutralizing antibody was present in 26.9%. Of note, 28.5% of patients with anti-RBD did not have neutralizing antibody. T cell responses in a sub-cohort of 48 patients showed a positive CD4+ T cell response in 47.9%. Of note, in this sub-cohort, 46.2% of patients with a negative anti-RBD, still had a positive CD4+ T cell response. The vaccine was safe and well-tolerated. In summary, immunogenicity of mRNA-1273 COVID-19 vaccine was modest, but a subset of patients still develop neutralizing antibody and CD4+T- cell responses. Importantly polyfunctional CD4+T cell responses were observed in a significant portion who were antibody negative, further highlighting the importance of vaccination in this patient population. IRB Statement: This study was approved by the University Health Network Research Ethics Board (CAPCR ID 20-6069).


Subject(s)
COVID-19 , Organ Transplantation , Antibodies, Neutralizing , Antibodies, Viral , COVID-19 Vaccines , Humans , Immunity, Cellular , Organ Transplantation/adverse effects , SARS-CoV-2
10.
Am J Transplant ; 21(8): 2709-2718, 2021 08.
Article in English | MEDLINE | ID: mdl-33484237

ABSTRACT

The humoral immune response to influenza virus infection is complex and may be different compared to the antibody response elicited by vaccination. We analyzed the breadth of IgG and IgA responses in solid organ transplant (SOT) recipients to a diverse collection of 86 influenza antigens elicited by natural influenza A virus (IAV) infection or by vaccination. Antibody levels were quantified using a custom antigen microarray. A total of 120 patients were included: 80 IAV infected (40 A/H1N1 and 40 A/H3N2) and 40 vaccinated. Based on hierarchical clustering analysis, infection with either H1N1 or H3N2 virus showed a more diverse antibody response compared to vaccination. Similarly, H1N1-infected individuals showed a significant IgG response to 27.9% of array antigens and H3N2-infected patients to 43.0% of antigens, whereas vaccination elicited a less broad immune response (7.0% of antigens). Immune responses were not exclusively targeting influenza hemagglutinin (HA) proteins but were also directed against conserved influenza antigens. Serum IgA responses followed a similar profile. This study provides novel data on the breadth of antibody responses to influenza. We also found that the diversity of response is greater in influenza-infected rather than vaccinated patients, providing a potential mechanistic rationale for suboptimal vaccine efficacy in this population.


Subject(s)
Influenza A Virus, H1N1 Subtype , Influenza Vaccines , Influenza, Human , Antibodies, Viral , Humans , Influenza A Virus, H3N2 Subtype , Influenza, Human/prevention & control , Transplant Recipients , Vaccination
11.
Am J Transplant ; 21(6): 2246-2253, 2021 06.
Article in English | MEDLINE | ID: mdl-33565711

ABSTRACT

Lung transplant recipients are at high risk for herpes zoster and preventive measures are a significant unmet need. We investigated the safety and immunogenicity of two doses of a recombinant zoster vaccine (RZV) in lung transplant recipients (≥50 years). We enrolled 50 patients of which 49 received at least one vaccine dose. Anti-glycoprotein E (gE) antibody levels (n = 43) increased significantly compared to baseline (median optical density [OD] 1.96; interquartile range [IQR]: 1.17-2.89) after the first (median OD 3.41, IQR 2.54-3.81, p < .0001) and second vaccine dose (median OD 3.63, IQR 3.39-3.86, p < .0001). gE-specific polyfunctional CD4+ T cell frequencies (n = 38) also increased from baseline (median 85 per 106 CD4+ T cells; IQR: 46-180) to the first (median 128 per 106 CD4+ T cells; IQR: 82-353; p = .023) and after the second dose (median 361 per 106 CD4+ T cells; IQR: 146-848; p < .0001). Tenderness (83.0%; 95%CI: 69.2-92.4%) and redness (31.9%; 95%CI: 19.1-47.1%) at injection site were common. One rejection episode within 3 weeks of vaccination was observed. This is the first study demonstrating that RZV was safe and elicited significant humoral and cell-mediated immunity in lung transplant recipients. RZV is a new option for the prevention of shingles in this population.


Subject(s)
Herpes Zoster Vaccine , Herpes Zoster , Antibodies, Viral , Herpes Zoster Vaccine/adverse effects , Humans , Lung , Transplant Recipients
12.
J Infect Dis ; 221(1): 53-62, 2020 01 01.
Article in English | MEDLINE | ID: mdl-31550354

ABSTRACT

BACKGROUND: Despite annual immunization, solid organ transplant (SOT) patients remain at increased risk for severe influenza infection because of suboptimal vaccine immunogenicity. We aimed to compare the CD4+ and CD8+ T-cell responses of the high-dose (HD) and the standard-dose (SD) trivalent inactivated vaccine. METHODS: We collected peripheral blood mononuclear cells pre- and postimmunization from 60 patients enrolled in a randomized trial of HD versus SD vaccine (30 HD; 30 SD) during the 2016-2017 influenza season. RESULTS: The HD vaccine elicited significantly greater monofunctional and polyfunctional CD4+ and CD8+ T-cell responses against influenza A/H1N1, A/H3N2, and B. For example, median vaccine-elicited influenza-specific polyfunctional CD4+ T cells were higher in recipients of the HD than SD vaccine after stimulation with influenza A/H1N1 (1193 vs 0 per 106 CD4+ T cells; P = .003), A/H3N2 (1154 vs 51; P = .008), and B (1102 vs 0; P = .001). Likewise, vaccine-elicited influenza-specific polyfunctional CD8+ T cells were higher in recipients of the HD than SD vaccine after stimulation with influenza B (367 vs 0; P = .002). CONCLUSIONS: Our study provides novel evidence that HD vaccine elicits greater cellular responses compared with the SD vaccine in SOT recipients, which provides support to preferentially consider use of HD vaccination in the SOT setting.


Subject(s)
Immunity, Cellular/immunology , Influenza A Virus, H1N1 Subtype/immunology , Influenza A Virus, H3N2 Subtype/immunology , Influenza B virus/immunology , Influenza Vaccines/immunology , Influenza, Human/immunology , CD4 Lymphocyte Count , CD4-Positive T-Lymphocytes/immunology , CD8-Positive T-Lymphocytes/immunology , Female , Humans , Immunocompromised Host/immunology , Immunogenicity, Vaccine , Influenza Vaccines/administration & dosage , Influenza, Human/virology , Male , Middle Aged , Organ Transplantation , Vaccine Potency
13.
J Infect Dis ; 219(4): 535-539, 2019 01 29.
Article in English | MEDLINE | ID: mdl-30192949

ABSTRACT

Influenza is responsible for significant morbidity after transplantation. We evaluated T-helper 1/T-helper 2 (Th2) cytokines and interleukin (IL) 10 levels during influenza infection in the posttransplant setting. Serum samples from 277 transplant recipients were analyzed at influenza diagnosis and 28 days later for interferon gamma (IFN-γ), IL-4, IL-13, and IL-10. IL-13 levels were associated with protection against pneumonia and intensive care unit (ICU) admission, whereas the IFN-γ/IL-13 ratio and IL-10 levels were associated with an increased risk of pneumonia and ICU admission. This association was independent of viral load. A skewing of immune responses toward Th2 in transplant patients appears to confer protection from severe influenza infection, independent of viral load.


Subject(s)
Cytokines/blood , Influenza, Human/pathology , Pneumonia, Viral/pathology , Transplant Recipients , Adult , Aged , Female , Humans , Male , Middle Aged , Prospective Studies , Serum/chemistry , Viral Load
14.
Am J Transplant ; 19(9): 2495-2504, 2019 09.
Article in English | MEDLINE | ID: mdl-30916879

ABSTRACT

Cytomegalovirus (CMV) is an immunomodulatory virus that indirectly increases the risk for bacterial, fungal, and viral infections. However, the pathogenesis of this phenomenon is poorly understood. We determined whether inflammatory responses to different Toll-like receptor (TLR) ligands are blunted during CMV infection in solid-organ transplant (SOT) patients. Peripheral blood mononuclear cells from 38 SOT patients with and without CMV were incubated in the presence of various viral, fungal, and bacterial TLR ligands. Cytokines were measured in the supernatant by multiplex enzyme-linked immunosorbent assay. Patients had blunted cytokine responses to bacterial, fungal, and viral ligands during CMV infection when compared to the absence of CMV infection. This was independent of viral load, clinical presentation of CMV infection or immunosuppression, supporting the clinical observation in SOT recipients that CMV infection increases susceptibility to bacterial, fungal, and other viral infections. Moreover, in the absence of CMV infection, patients with subsequent CMV infection had lower cytokines in response to TLR ligands compared to those without subsequent CMV infection, suggesting that inherent differences in patients not directly related to CMV also contribute to this increased susceptibility. In summary, these data provide novel ex vivo evidence to support indirect effects of CMV.


Subject(s)
Cytomegalovirus Infections/complications , Inflammation/metabolism , Toll-Like Receptors/metabolism , Transplant Recipients , Transplantation/adverse effects , Adult , Antiviral Agents/therapeutic use , Cytokines/metabolism , Cytomegalovirus , Female , Ganciclovir/therapeutic use , Humans , Immunosuppression Therapy/adverse effects , Inflammation/immunology , Leukocytes, Mononuclear/cytology , Ligands , Male , Middle Aged , Organ Transplantation , Pilot Projects , Postoperative Complications , Prospective Studies , Valganciclovir/therapeutic use , Viral Load
15.
Am J Transplant ; 19(8): 2318-2328, 2019 08.
Article in English | MEDLINE | ID: mdl-30748090

ABSTRACT

The humoral immune response of transplant recipients to influenza vaccination has been studied in detail. In contrast, the hemagglutinin inhibiting (HI) antibody response evoked by natural influenza infection and its impact on viral kinetics is unknown. In this prospective, multicenter, cohort study of natural influenza infection in transplant recipients, we measured HI antibody titers at presentation and 4 weeks later. Serial nasopharyngeal viral loads were determined using a quantitative influenza A polymerase chain reaction (PCR). We analyzed 196 transplant recipients with influenza infection. In the cohort of organ transplant patients with influenza A (n = 116), seropositivity rates for strain-specific antibodies were 44.0% (95% confidence interval [CI] 31.5-53.2%) at diagnosis and 64.7% (95% CI 55.4-72.9%) 4 weeks postinfection. Seroconversion was observed in 32.8% (95% CI 24.7-41.9%) of the cases. Lung transplant recipients were more likely to seroconvert (P = .002) and vaccine recipients were less likely to seroconvert (P = .024). A subset of patients (n = 30) who were unresponsive to prior vaccination were also unresponsive to natural infection. There was no correlation between viral kinetics and antibody response. This study provides novel data on the seroresponse to influenza infection in transplant patients and its relationship to a number of parameters including a prior vaccination status, virologic measures, and clinical variables.


Subject(s)
Antibodies, Viral/immunology , Immunity, Humoral/immunology , Influenza A virus/immunology , Influenza B virus/immunology , Influenza, Human/immunology , Transplant Recipients/statistics & numerical data , Transplantation Immunology/immunology , Adult , Female , Follow-Up Studies , Humans , Influenza Vaccines/immunology , Influenza, Human/prevention & control , Male , Middle Aged , Organ Transplantation , Prognosis , Prospective Studies
17.
Clin Infect Dis ; 67(9): 1322-1329, 2018 10 15.
Article in English | MEDLINE | ID: mdl-29635437

ABSTRACT

Background: Seasonal influenza infection may cause significant morbidity and mortality in transplant recipients. The purpose of this study was to assess the epidemiology of symptomatic influenza infection posttransplant and determine risk factors for severe disease. Methods: Twenty centers in the United States, Canada, and Spain prospectively enrolled solid organ transplant (SOT) or hematopoietic stem cell transplant (HSCT) recipients with microbiologically confirmed influenza over 5 consecutive years (2010-2015). Demographics, microbiology data, and outcomes were collected. Serial nasopharyngeal swabs were collected at diagnosis and upto 28 days, and quantitative polymerase chain reaction for influenza A was performed. Results: We enrolled 616 patients with confirmed influenza (477 SOT; 139 HSCT). Pneumonia at presentation was in 134 of 606 (22.1%) patients. Antiviral therapy was given to 94.1% for a median of 5 days (range, 1-42 days); 66.5% patients were hospitalized and 11.0% required intensive care unit (ICU) care. The receipt of vaccine in the same influenza season was associated with a decrease in disease severity as determined by the presence of pneumonia (odds ratio [OR], 0.34 [95% confidence interval {CI}, .21-.55], P < .001) and ICU admission (OR, 0.49 [95% CI, .26-.90], P = .023). Similarly, early antiviral treatment (within 48 hours) was associated with improved outcomes. In patients with influenza A, pneumonia, ICU admission, and not being immunized were also associated with higher viral loads at presentation (P = .018, P = .008, and P = .024, respectively). Conclusions: Annual influenza vaccination and early antiviral therapy are associated with a significant reduction in influenza-associated morbidity, and should be emphasized as strategies to improve outcomes of transplant recipients.


Subject(s)
Influenza, Human/epidemiology , Transplant Recipients , Adolescent , Adult , Aged , Aged, 80 and over , Antiviral Agents/therapeutic use , Canada/epidemiology , Child , Child, Preschool , Female , Hospitalization/statistics & numerical data , Humans , Infant , Influenza Vaccines/therapeutic use , Influenza, Human/drug therapy , Male , Middle Aged , Prospective Studies , Risk Factors , Spain/epidemiology , United States/epidemiology , Vaccination , Young Adult
18.
Anal Bioanal Chem ; 410(19): 4749-4762, 2018 Jul.
Article in English | MEDLINE | ID: mdl-29806067

ABSTRACT

In this study, a series of polymeric ionic liquid (PIL) sorbent coatings is evaluated for the extraction of polar volatile organic compounds (VOCs) from Brazilian wines using headspace solid-phase microextraction (HS-SPME), including samples from 'Isabella' and 'BRS Magna' cultivars-the latter was recently introduced by the Brazilian Agricultural Research Corporation - National Grape & Wine Research Center. The structurally tuned SPME coatings were compared to the commercial SPME phases, namely poly(acrylate) (PA) and divinylbenzene/carboxen/poly(dimethylsiloxane) (DVB/CAR/PDMS). The separation, detection and identification of the aroma profiles were obtained using comprehensive two-dimensional gas chromatography mass spectrometry (GC×GC-MS). The best performing PIL-based SPME fiber, namely 1-hexadecyl-3-vinylimidazolium bis[(trifluoromethyl)sulfonyl]imide with 1,12-di(3-vinylimidazolium)dodecane dibis[(trifluoromethyl)sulfonyl]imide incorporated cross-linker supported on an elastic nitinol wire, exhibited superior performance to DVB/CAR/PDMS regarding the average number of extracted peaks and extracted more polar analytes providing additional insight into the aroma profile of 'BRS Magna' wines. Four batches of wine were evaluated, namely 'Isabella' and 'BRS Magna' vintages 2015 and 2016, using highly selective PIL-based SPME coatings and enabled the detection of 350+ peaks. Furthermore, this is the first report evaluating the aroma of 'BRS Magna' wines. A hybrid approach that combined pixel-based Fisher ratio and peak table-based data comparison was used for data handling. This proof-of-concept experiment provided reliable and statistically valid distinction of wines that may guide regulation agencies to create high sample throughput protocols to screen wines exported by Brazilian vintners. Graphical abstract Highly selective extraction of wine aroma using polymeric ionic liquid.


Subject(s)
Gas Chromatography-Mass Spectrometry/methods , Ionic Liquids/chemistry , Odorants/analysis , Solid Phase Microextraction/methods , Wine/analysis , Brazil , Discriminant Analysis , Polymers/chemistry
19.
J Infect Dis ; 215(4): 537-546, 2017 02 15.
Article in English | MEDLINE | ID: mdl-28003351

ABSTRACT

Background: Homo sapiens mature micro-ribonucleic acid (miRNA)-200b-3p and 200c-3p are predicted to bind to 3' untranslated region of mRNA encoding human cytomegalovirus (HCMV) immediate early protein 2 (IE2). We hypothesized that expression of these miRNAs pretransplant could predict HCMV replication after solid organ transplantation (SOT). Methods: A total of 272 SOT recipients were HCMV-seropositive pretransplant and were managed using preemptive therapy. Pretransplant peripheral blood mononuclear cells were stimulated with HCMV followed by collection of RNA 1 day poststimulation. The miRNAs were quantified using real-time reverse transcription-polymerase chain reaction. Human foreskin fibroblasts were transfected with 200b-3p and 200c-3p and infected with HCMV 1 hour post-transfection. Protein was collected at 3 days postinfection (dpi) and 7 dpi underwent immunoblotting for IE2. Results: Medians of 200b-3p and 200c-3p were significantly lower in recipients with HCMV replication (n = 144) (361.6 vs 552.6, P = .035; 3586.8 vs 12986.8 copies/µL, P = .03, respectively). Multivariate regression revealed that 200b-3p ≥100 copies/µL (odds ratio [OR]: 0.53; P = .02), was associated with less HCMV replication. Transfection with 200b-3p resulted in 2.7- and 2.5-fold decreased IE2 at 3 dpi and 7 dpi, respectively, compared to mock cells. Conclusions: MicroRNAs may play a biologically relevant role in controlling HCMV replication post-transplant.


Subject(s)
Cytomegalovirus Infections/virology , Cytomegalovirus/physiology , MicroRNAs/metabolism , Organ Transplantation , Virus Replication , Adult , Aged , Cell Line , Female , Follow-Up Studies , HeLa Cells , Humans , Immediate-Early Proteins/genetics , Immediate-Early Proteins/metabolism , Leukocytes, Mononuclear/metabolism , Leukocytes, Mononuclear/virology , Logistic Models , Male , MicroRNAs/genetics , Middle Aged , Multivariate Analysis , Prospective Studies , RNA, Messenger/genetics , RNA, Messenger/metabolism , Reproducibility of Results
20.
J Infect Dis ; 211(11): 1745-56, 2015 Jun 01.
Article in English | MEDLINE | ID: mdl-25538276

ABSTRACT

Although clinical and experimental evidence indicates that female sex hormones and hormonal contraceptives regulate susceptibility to human immunodeficiency virus type 1 (HIV-1) infection, the underlying mechanism remains unknown. Genital epithelial cells (GECs) are the first cells to encounter HIV during sexual transmission and their interaction with HIV may determine the outcome of exposure. This is the first report that HIV uptake by GECs increased significantly in the presence of the hormonal contraceptive medroxyprogesterone acetate (MPA) and progesterone and that uptake occurred primarily via endocytosis. No productive infection was detected, but endocytosed virus was released into apical and basolateral compartments. Significantly higher viral transcytosis was observed in the presence of MPA. In GEC and T-cell cocultures, maximum viral replication in T cells was observed in the presence of MPA, which also broadly upregulated chemokine production by GECs. These results suggest that MPA may play a significant role in regulating susceptibility to HIV.


Subject(s)
Epithelial Cells/virology , HIV Infections/virology , HIV-1/drug effects , Medroxyprogesterone Acetate/pharmacology , T-Lymphocytes/virology , Virus Internalization/drug effects , Virus Replication/drug effects , Cells, Cultured , Contraceptive Agents, Female/pharmacology , Cytokines/metabolism , Endocytosis , Female , Humans , Progesterone/pharmacology , Up-Regulation , Uterus/cytology
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