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1.
Nat Immunol ; 21(9): 1107-1118, 2020 09.
Artículo en Inglés | MEDLINE | ID: mdl-32788748

RESUMEN

In coronavirus disease 2019 (COVID-19), caused by severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection, the relationship between disease severity and the host immune response is not fully understood. Here we performed single-cell RNA sequencing in peripheral blood samples of 5 healthy donors and 13 patients with COVID-19, including moderate, severe and convalescent cases. Through determining the transcriptional profiles of immune cells, coupled with assembled T cell receptor and B cell receptor sequences, we analyzed the functional properties of immune cells. Most cell types in patients with COVID-19 showed a strong interferon-α response and an overall acute inflammatory response. Moreover, intensive expansion of highly cytotoxic effector T cell subsets, such as CD4+ effector-GNLY (granulysin), CD8+ effector-GNLY and NKT CD160, was associated with convalescence in moderate patients. In severe patients, the immune landscape featured a deranged interferon response, profound immune exhaustion with skewed T cell receptor repertoire and broad T cell expansion. These findings illustrate the dynamic nature of immune responses during disease progression.


Asunto(s)
Antígenos CD/metabolismo , Antígenos de Diferenciación de Linfocitos T/metabolismo , Betacoronavirus/inmunología , Infecciones por Coronavirus/inmunología , Interferón Tipo I/metabolismo , Neumonía Viral/inmunología , Receptores Inmunológicos/metabolismo , Adolescente , Adulto , Anciano , Antígenos CD/genética , Antígenos CD/inmunología , Antígenos de Diferenciación de Linfocitos T/genética , Antígenos de Diferenciación de Linfocitos T/inmunología , Linfocitos T CD4-Positivos/inmunología , Linfocitos T CD4-Positivos/metabolismo , Linfocitos T CD8-positivos/inmunología , Linfocitos T CD8-positivos/metabolismo , COVID-19 , Estudios de Cohortes , Infecciones por Coronavirus/sangre , Infecciones por Coronavirus/diagnóstico , Infecciones por Coronavirus/virología , Femenino , Proteínas Ligadas a GPI/genética , Proteínas Ligadas a GPI/inmunología , Proteínas Ligadas a GPI/metabolismo , Humanos , Interferón Tipo I/genética , Interferón Tipo I/inmunología , Células Asesinas Naturales/inmunología , Células Asesinas Naturales/metabolismo , Masculino , Persona de Mediana Edad , Pandemias , Neumonía Viral/sangre , Neumonía Viral/diagnóstico , Neumonía Viral/virología , RNA-Seq , Receptores Inmunológicos/genética , Receptores Inmunológicos/inmunología , SARS-CoV-2 , Índice de Severidad de la Enfermedad , Análisis de la Célula Individual
2.
Nature ; 584(7819): 120-124, 2020 08.
Artículo en Inglés | MEDLINE | ID: mdl-32454512

RESUMEN

An outbreak of coronavirus disease 2019 (COVID-19)1-3, caused by severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2)4, has spread globally. Countermeasures are needed to treat and prevent further dissemination of the virus. Here we report the isolation of two specific human monoclonal antibodies (termed CA1 and CB6) from a patient convalescing from COVID-19. CA1 and CB6 demonstrated potent SARS-CoV-2-specific neutralization activity in vitro. In addition, CB6 inhibited infection with SARS-CoV-2 in rhesus monkeys in both prophylactic and treatment settings. We also performed structural studies, which revealed that CB6 recognizes an epitope that overlaps with angiotensin-converting enzyme 2 (ACE2)-binding sites in the SARS-CoV-2 receptor-binding domain, and thereby interferes with virus-receptor interactions by both steric hindrance and direct competition for interface residues. Our results suggest that CB6 deserves further study as a candidate for translation to the clinic.


Asunto(s)
Anticuerpos Neutralizantes/inmunología , Anticuerpos Antivirales/inmunología , Betacoronavirus/inmunología , Infecciones por Coronavirus/inmunología , Infecciones por Coronavirus/virología , Neumonía Viral/inmunología , Neumonía Viral/virología , Glicoproteína de la Espiga del Coronavirus/química , Glicoproteína de la Espiga del Coronavirus/inmunología , Enzima Convertidora de Angiotensina 2 , Animales , Anticuerpos Neutralizantes/química , Anticuerpos Neutralizantes/farmacología , Anticuerpos Antivirales/química , Anticuerpos Antivirales/farmacología , Betacoronavirus/química , Unión Competitiva , COVID-19 , Línea Celular , Chlorocebus aethiops , Cristalización , Cristalografía por Rayos X , Femenino , Humanos , Técnicas In Vitro , Macaca mulatta/inmunología , Macaca mulatta/virología , Masculino , Modelos Moleculares , Pruebas de Neutralización , Pandemias , Peptidil-Dipeptidasa A/química , Peptidil-Dipeptidasa A/metabolismo , Unión Proteica/efectos de los fármacos , SARS-CoV-2 , Glicoproteína de la Espiga del Coronavirus/antagonistas & inhibidores , Glicoproteína de la Espiga del Coronavirus/metabolismo , Células Vero , Carga Viral/inmunología
3.
Sex Transm Infect ; 2024 May 24.
Artículo en Inglés | MEDLINE | ID: mdl-38789266

RESUMEN

OBJECTIVE: Sub-Saharan Africa is one of the regions with the highest burdens of HIV and hepatitis B virus (HBV), but data on the impact of antiretroviral therapy (ART) on HBV DNA suppression is limited. In this study, we aimed to determine the prevalence and associated factors of a positive hepatitis B surface antigen (HBsAg) among people living with HIV, and assess the suppression of ART on HBV replication in people living with HIV in Sierra Leone. METHODS: A cross-sectional study was designed to recruit people living with HIV aged 18 years or older in ten public hospitals in Sierra Leone between August 2022 and January 2023. Statistical analyses were performed using R software. Logistic regression analysis was used to assess factors independently associated with positive HBsAg and HBV DNA suppression. RESULTS: Of the 3106 people living with HIV recruited in this study, 2311 (74.4%) were women. The median age was 36 years, 166 (5.3%) had serological evidence of HBV vaccination. The overall prevalence of HBsAg positivity was 12.0% (95% CI: 10.9% to 13.2%). Male sex (adjusted OR (aOR) 2.11, 95% CI: 1.67 to 2.68; p<0.001) and being separated (aOR 1.83, 95% CI: 1.06 to 3.16, p=0.031; reference group: being married) were independent predictors of HBsAg seropositivity. Among 331 people living with HIV and HBV receiving ART, 242 (73.1%) achieved HBV DNA suppression (below 20 IU/mL). HBV suppression rate was higher in HIV-virally suppressed patients than those with unsuppressed HIV viral load (p<0.001). In addition, the male sex was more likely to have unsuppressed HBV DNA (aOR 1.17, 95% CI: 1.17 to 3.21; p=0.010). CONCLUSIONS: We reported a high prevalence of HBsAg seropositivity and low HBV immunisation coverage in people living with HIV in Sierra Leone. In addition, we observed that ART can efficiently result in a viral suppression rate of HBV infection. Therefore, achieving the global target of eliminating HBV infection by 2030 requires accelerated access to care for people living with HIV and HBV, including HBV testing, antiviral treatment and hepatitis B vaccination.

4.
Gut ; 72(1): 153-167, 2023 01.
Artículo en Inglés | MEDLINE | ID: mdl-35361683

RESUMEN

OBJECTIVE: A comprehensive immune landscape for HBV infection is pivotal to achieve HBV cure. DESIGN: We performed single-cell RNA sequencing of 2 43 000 cells from 46 paired liver and blood samples of 23 individuals, including six immune tolerant, 5 immune active (IA), 3 acute recovery (AR), 3 chronic resolved and 6 HBV-free healthy controls (HCs). Flow cytometry and histological assays were applied in a second HBV cohort for validation. RESULTS: Both IA and AR were characterised by high levels of intrahepatic exhausted CD8+ T (Tex) cells. In IA, Tex cells were mainly derived from liver-resident GZMK+ effector memory T cells and self-expansion. By contrast, peripheral CX3CR1+ effector T cells and GZMK+ effector memory T cells were the main source of Tex cells in AR. In IA but not AR, significant cell-cell interactions were observed between Tex cells and regulatory CD4+ T cells, as well as between Tex and FCGR3A+ macrophages. Such interactions were potentially mediated through human leukocyte antigen class I molecules together with their receptors CANX and LILRBs, respectively, contributing to the dysfunction of antiviral immune responses. By contrast, CX3CR1+GNLY+ central memory CD8+ T cells were concurrently expanded in both liver and blood of AR, providing a potential surrogate marker for viral resolution. In clinic, intrahepatic Tex cells were positively correlated with serum alanine aminotransferase levels and histological grading scores. CONCLUSION: Our study dissects the coordinated immune responses for different HBV infection phases and provides a rich resource for fully understanding immunopathogenesis and developing effective therapeutic strategies.


Asunto(s)
Linfocitos T CD8-positivos , Hígado , Humanos , Hígado/patología , Antivirales , Linfocitos T Reguladores , Análisis de Secuencia de ARN , Virus de la Hepatitis B
5.
Virol J ; 20(1): 279, 2023 Nov 29.
Artículo en Inglés | MEDLINE | ID: mdl-38031075

RESUMEN

INTRODUCTION: Viral load assessment for people living with HIV is key for monitoring treatment and achieving the 95-95-95. In this study, we aimed to assess the degree of viral suppression at different thresholds and treatment duration after the introduction of dolutegravir-based therapy in ten public hospitals in Sierra Leone. METHODS: We used a cross-sectional study design to recruits patients aged 18 years or older between August 2022 and January 2023. Statistical analyses were performed using R-software. Logistic regression was used to assess factors independently associated with viral suppression. The level of significance was set at P < 0.05. RESULTS: Of the 2,253 patients recruited, 1,720 (76%) were women and 1,705 (76%) were receiving a fixed dose combination of tenofovir, lamivudine and dolutegravir. The median age and duration of anti-retroviral therapy (ART) was 36.0 (IQR, 28.0-45.0) years and 40.9 (IQR, 14.4-79.6) months, respectively. Using a threshold of HIV RNA < 1000 copies/mL, 1,715 (88.4%) patients on ART for more than 6 months were virally suppressed. Viral suppression rates were higher with dolutegravir-based (1,277, 89.5%) than efavirenz-based (418, 86.2%) ART. HIV RNA was < 200 copies/mL in 1,643 (84.6%) patients or < 50 copies/mL in 1,487 (76.6%) patients or between 50 and 999 copies/mL in 228 (11.7%) patients. Viral suppression rates at different ART durations (months) were as follows: 84.2% (≤ 3), 88.8% (4-6), 90.9% (6-12), and 88.1% (> 12). Viral suppression rates were higher for patients aged 40 or older (40-50 years: aOR 2.05, 95%CI 1.41-3.04, P < 0.01; 50-60 years: aOR 2.51, 95%CI 1.53-4.35, P < 0.01; >60 years: aOR 2.69, 95%CI 1.28-6.63, P = 0.02). Men had 49% lower odds of viral suppression than women (aOR 0.50, 95% CI 0.38-0.67, P < 0.01). CONCLUSION: We report a viral suppression rate of 88.4% among patients on treatment for at least 6 months, with higher rate of suppression with dolutegravir than efavirenz. Factors associated with virological suppression were age and gender, emphasizing the need for innovative differentiated ART delivery models to optimize viral suppression and achieve the 95% target.


Asunto(s)
Fármacos Anti-VIH , Infecciones por VIH , Masculino , Humanos , Femenino , Duración de la Terapia , Sierra Leona , Estudios Transversales , Benzoxazinas/efectos adversos , Oxazinas/uso terapéutico , Infecciones por VIH/tratamiento farmacológico , ARN , Carga Viral , Fármacos Anti-VIH/uso terapéutico
6.
BMC Infect Dis ; 23(1): 762, 2023 Nov 06.
Artículo en Inglés | MEDLINE | ID: mdl-37932713

RESUMEN

BACKGROUND: Globally, there were an estimated 7.1 million new syphilis infections in 2020, with more than 30% of these new infections reported in African countries such as Sierra Leone. Despite this, there is no HIV-specific syphilis screening program in Sierra Leone. Thus, data are needed to inform public health practice. In this study, we aimed to determine the prevalence of syphilis seropositivity and factors associated with syphilis seropositivity among people living with HIV (PLHIV). METHODS: A cross-sectional study was conducted at 10 health facilities in Sierra Leone, among adults with HIV, aged 18 years or older, from September 2022 to January 2023. Parameters of interest were collected including age, sex, marriage, antiretroviral therapy (ART) regimen, HIV viral load, duration of ART treatment, and hospital level of care. The syphilis antibody was detected by a rapid test based on immunochromatography assay. Data were analyzed using R-software version 4.2.3 (R Core Team, Vienna, Austria). Pearson's χ2 test, Fisher's exact test and Kruskal-Wallis H test were applied to assess the differences in syphilis seropositivity between groups as appropriate. Univariate logistic regression and multivariate logistic regression analysis was used to assess factors associated with syphilis seropositivity. The level of statistical significance was set at P < 0.05. RESULTS: Of the 3082 PLHIV individuals in our study, 2294 (74.4%) were female and 2867 (93.0%) were receiving ART. With a median age of 36 years, 211 (6.8%, 95% CI 6.0-7.7) were positive for syphilis. The prevalence of syphilis was highest in people aged 60 years and over (21.1%, 95%CI 14.7-29.2), followed by people aged 50-60 years (15.5%, 95%CI 11.9-19.9) and in the widowed population (11.9%, 95%CI 8.9-15.8). There were no differences in syphilis seropositivity between gender, ART status, ART regimen, duration of ART, HIV viral load and hospital level of care. Older age (50-60 years: adjusted OR 3.49, 95%CI 2.09-5.85 P < 0.001; 60-100 years: adjusted OR 4.28, 95%CI 2.21-8.17, P < 0.001) was an independent predictor of seropositive syphilis. CONCLUSIONS: We observed a high prevalence of syphilis among PLHIV. Older people and widowed population have higher syphilis seropositivity. Older age was an independent predictor of syphilis positivity. Therefore, we call for the integration of syphilis screening, treatment and prevention in HIV services.


Asunto(s)
Infecciones por VIH , Sífilis , Adulto , Humanos , Femenino , Persona de Mediana Edad , Anciano , Masculino , Estudios Transversales , Sífilis/epidemiología , Sierra Leona/epidemiología , Prevalencia , Infecciones por VIH/epidemiología , Hospitales
7.
BMC Infect Dis ; 23(1): 893, 2023 Dec 20.
Artículo en Inglés | MEDLINE | ID: mdl-38124099

RESUMEN

BACKGROUND: Antiretroviral therapy (ART) can reduce viral load in individuals infected with human immunodeficiency virus (HIV); however, some HIV-infected individuals still cannot achieve optimal immune recovery even after ART. Hence, we described the profile of peripheral immune cells and explored the association with disease progression in patients infected with HIV-1. METHODS: Mass cytometry analysis was used to characterize the circulating immune cells of 20 treatment-naïve (TNs), 20 immunological non-responders (INRs), 20 immunological responders (IRs), and 10 healthy controls (HCs). Correlation analysis was conducted between cell subpopulation percentages and indicators including HIV-1 cell-associated (CA)-RNA, DNA, CD4+ T cell count, and CD4/CD8 ratio. RESULTS: Global activation, immunosenescence, and exhaustion phenotypes were observed in myeloid cells and T cells from individuals with HIV-1 infection. We also found that specific subsets or clusters of myeloid, CD4+ T, and CD8+ T cells were significantly lost or increased in TN individuals, which could be partially restored after receiving ART. The percentages of several subpopulations correlated with HIV-1 CA-RNA, DNA, CD4+ T cell count, and CD4/CD8 ratio, suggesting that changes in immune cell composition were associated with therapeutic efficacy. CONCLUSION: These data provide a complete profile of immune cell subpopulations or clusters that are associated with disease progression during chronic HIV-1 infection, which will improve understanding regarding the mechanism of incomplete immune recovery in INRs.


Asunto(s)
Infecciones por VIH , VIH-1 , Humanos , Linfocitos T CD8-positivos , ARN , Progresión de la Enfermedad , ADN , Linfocitos T CD4-Positivos , Carga Viral , Recuento de Linfocito CD4
8.
Eur J Immunol ; 51(8): 2027-2039, 2021 08.
Artículo en Inglés | MEDLINE | ID: mdl-33974710

RESUMEN

Immune deficiency is one of the hallmarks of HIV infection and a major cause of adverse outcomes in people living with HIV (PLWH). Long-lived memory CD8+ T cells (LLMCs) are essential executors of long-term protective immunity; however, the generation and maintenance of LLMCs during chronic HIV infection are not well understood. In the present study, we analyzed circulating LLMCs in healthy controls (HCs) and PLWH with different disease statuses, including treatment naïve patients (TNs), complete responders (CRs), and immunological nonresponders (INRs). We found that both TNs and INRs showed severely compromised LLMCs compared with HCs and CRs, respectively. The decrease of LLMCs in TNs correlated positively with the reduction of their precursors, namely memory precursor effector T cells (MPECs), which might be associated with elevated pro-inflammatory cytokines. Strikingly, INRs showed an accumulation of MPECs, which exhibited diminished responsiveness to interleukin 7 (IL-7), thereby indicating abrogated differentiation into LLMCs. Moreover, in vitro studies showed that treatment with dexamethasone could improve the IL7-phosphorylated (p)-signal transducer and activator of transcription (STAT5) response by upregulating the expression of the interleukin 7 receptor (IL-7Rα) on MPECs in INRs. These findings provide insights that will encourage the development of novel therapeutics to improve immune function in PLWH.


Asunto(s)
Linfocitos T CD8-positivos/inmunología , Infecciones por VIH/inmunología , Memoria Inmunológica/inmunología , Interleucina-7/inmunología , Adulto , Femenino , Humanos , Masculino , Persona de Mediana Edad
9.
HIV Med ; 23 Suppl 1: 106-114, 2022 03.
Artículo en Inglés | MEDLINE | ID: mdl-35293101

RESUMEN

INTRODUCTION: To investigate the characteristics of ß7high CD4+ T cells during HIV-1 infection and the relationship between ß7high CD4+ T cells and HIV-1 disease progress. METHODS: This study enrolled 124 HIV-1-infected patients, including 80 treatment naïve patients (TNs), 41 patients who underwent antiretroviral therapy (ARTs), and three long-term no progression patients (LTNPs). Nineteen matched healthy subjects were included as controls (HCs). The characteristics and frequency of ß7high CD4+ T cells were analyzed using flow cytometry. An in vitro culture experiment was used to study HIV-1 infection of ß7high CD4+ T cells. Real-time polymerase chain reaction was performed to quantify HIV-1 DNA and CA-RNA levels. RESULTS: The frequency of ß7high CD4+ T in the peripheral blood was significantly decreased and negatively correlated with disease progression during chronic HIV-1 infection. A large proportion of ß7high CD4+ T cells showed Th17 phenotype. Furthermore, ß7high CD4+ T cells were preferentially infected by HIV-1 in vitro and in vivo. There were no significant differences of HIV-1 DNA, and CA-RNA levels between ß7high CD4+ T and ß7low CD4+ T subsets in HIV-1 infected individuals after antiviral treatment. CONCLUSION: The ß7high CD4+ T cells were negatively correlated with disease progression during chronic HIV-1 infection. ß7high CD4+ T cells are susceptible to infection with HIV-1 and HIV-1 latent cells.


Asunto(s)
Infecciones por VIH , Seropositividad para VIH , VIH-1 , Linfocitos T CD4-Positivos , Progresión de la Enfermedad , Infecciones por VIH/tratamiento farmacológico , Humanos , ARN
10.
Clin Immunol ; 229: 108773, 2021 08.
Artículo en Inglés | MEDLINE | ID: mdl-34102315

RESUMEN

BACKGROUND: The dynamics of viral reservoir decay and naïve CD4 T-cell recovery between immunological non-responders (INR) and complete responders (CR) during long-term antiretroviral treatment (ART) are not fully known. METHODS: Twenty-eight chronic HIV-infected individuals on 5-year ART were divided into two groups: INR (CD4 counts ≤350 cells/µL, n = 13) and CR (CD4 counts ≥500 cells/µL, n = 15). The levels of HIV DNA and cell-associated HIV RNA (CA-RNA), CD4 counts, naïve CD4 counts and their correlations were analyzed at baseline, years 1, 3 and 5 of ART between the two groups. Expression of PD-1 on CD4 T-cells was quantified by flow cytometry. Linear mixed effect models were used to estimate the change procession in repeated measurements over 5 years. Slopes of the above-mentioned indicators were estimated using participant-specific linear regressions, respectively. RESULTS: INR maintained higher levels of HIV DNA and CA-RNA with higher percentages of PD-1+CD4 T-cells compared with CR during 5-year ART, concurrent with lower naïve CD4 T-cells. However, the rates of HIV DNA and CA-RNA decay in INR were not different from that in CR over time, and INR had higher rates of naïve CD4 T-cell percentage recovery. The baseline levels of HIV DNA were positively associated with the 5-year levels of HIV DNA, but negatively associated with the 5-year naïve CD4 counts. CONCLUSIONS: INR maintained significantly higher viral reservoir and lower naïve CD4 T-cells compared with CR during 5-year ART, however, the rates of reservoir decay and naïve CD4 T-cell percentage growth within INR were not lower than that in CR over time.


Asunto(s)
Terapia Antirretroviral Altamente Activa , Linfocitos T CD4-Positivos/inmunología , Infecciones por VIH/inmunología , Infecciones por VIH/virología , Adulto , Recuento de Linfocito CD4 , China , ADN Viral/sangre , ADN Viral/genética , Progresión de la Enfermedad , VIH/efectos de los fármacos , VIH/genética , Infecciones por VIH/tratamiento farmacológico , Sobrevivientes de VIH a Largo Plazo , Humanos , Modelos Lineales , Estudios Longitudinales , Masculino , Persona de Mediana Edad , ARN Viral/sangre , ARN Viral/genética , Factores de Tiempo , Carga Viral/efectos de los fármacos
11.
Nanotechnology ; 32(14): 145201, 2021 Apr 02.
Artículo en Inglés | MEDLINE | ID: mdl-33352536

RESUMEN

We demonstrate the use of a photonic crystal (PhC) structure to improve the performance of a germanium avalanche photodetector (APD) by simultaneously manipulating the distribution of the optical and electric fields. The PhC is fabricated at the top center of the vertical germanium APD. For a 14 µm diameter device, the 1550 nm responsivity increases from 0.2 to 0.6 A W-1 at unity gain, owing to the resonance-enhanced absorption. Moreover, the structure separates the absorption and multiplication regions of the device, resulting in an increase of the avalanche gain and the gain-bandwidth product. Under -10 dBm input optical power, a 3 dB bandwidth of 34 GHz before avalanche and a clear 40 Gbps eye diagram under avalanche demonstrates good high-speed performance of the device.

12.
Clin Infect Dis ; 71(16): 2066-2072, 2020 11 19.
Artículo en Inglés | MEDLINE | ID: mdl-32357209

RESUMEN

BACKGROUND: Thousands of medical staff have been infected with severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), with hundreds of deaths reported. Such loss could be prevented if there were a serologic assay for SARS-CoV-2-specific antibodies for serological surveillance of its infection at the early stage of disease. METHODS: Using Chinese hamster ovarian (CHO) cell-expressed full-length SARS-CoV-2 S1 protein as capturing antigen, a coronavirus disease 2019 (COVID-19)/SARS-CoV-2 S1 serology enzyme-linked immunosorbent assay (ELISA) kit was developed and validated with negative samples collected prior to the outbreak or during the outbreak and positive samples from patients confirmed with COVID-19. RESULTS: The specificity of the ELISA kit was 97.5%, as examined against total 412 normal human samples. The sensitivity was 97.1% by testing against 69 samples from hospitalized and/or recovered COVID-19 patients. The overall accuracy rate reached 97.3%. The assay was able to detect SARS-CoV-2 antibody on day 1 after the onset of COVID-19 disease. The average antibody levels increased during hospitalization and 14 days after discharge. SARS-CoV-2 antibodies were detected in 28 of 276 asymptomatic medical staff and 1 of 5 nucleic acid test-negative "close contacts" of COVID-19 patients. CONCLUSIONS: With the assays developed here, we can screen medical staff, incoming patients, passengers, and people who are in close contact with the confirmed patients to identify the "innocent viral spreaders," protect the medical staff, and stop further spread of the virus.


Asunto(s)
Anticuerpos Antivirales/sangre , COVID-19/sangre , COVID-19/epidemiología , Animales , Células CHO , COVID-19/virología , Cricetulus , Ensayo de Inmunoadsorción Enzimática , SARS-CoV-2/inmunología , SARS-CoV-2/patogenicidad , Pruebas Serológicas
13.
Nanotechnology ; 31(45): 455602, 2020 Nov 06.
Artículo en Inglés | MEDLINE | ID: mdl-32736366

RESUMEN

The application of ordered Ge quantum dots (QDs) is limited by the indirect bandgap and the large size. Here, a structure of hollow nanopillars (HNPs) is proposed to grow small ordered Ge QDs using molecular beam epitaxy by suppressing the expansion of the central holes (CHs) during degassing and inhibiting the lateral growth of Ge QDs, the growth mechanisms are explained by the evolution of surface morphology and the surface chemical potential distribution. The width of Ge QDs in CHs mainly depends on the diameter of HNPs and has little relationship to the diameter of CHs. The small ordered Ge QDs with a mean base diameter of 47.1 nm and a period of 1 µm are grown under high growth temperature (580 °C). The size, shape, height, and period of HNPs are all shown to affect the growth of Ge QDs in CHs. Hence, HNPs provide us with more controllable parameters than pits to control the shape, location, and size of Ge QDs.

14.
Nanotechnology ; 31(38): 385603, 2020 Sep 18.
Artículo en Inglés | MEDLINE | ID: mdl-32480391

RESUMEN

Semiconductor microcavities can greatly enhance the light-emission of embedded quantum dots (QDs). Here, a new route toward the microcavity-QD system by fabricating microcavities followed by growing ordered QDs on a patterned microresonator is proposed, which keeps QDs from being etched. Self-assembled Ge QDs prefer to form at the rims of Si microrings or microdisks. The Ge QDs on the pit- or groove-patterned microring resonator (MRR) show better size uniformity and position accuracy. These features are explained by the evolutions of surface morphology and surface chemical potential distribution. Sharp photoluminescence peaks in the telecommunication band with the quality factors in the range of 450-850 from groove-patterned MRR are observed at 295 K due to efficient overlap between Ge QDs and resonant modes. Our schemes shed light on the exactly site-controlled growth of QDs on micro- and nano-structures, which further facilitates the investigation of light-matter interactions.

15.
Microbiol Immunol ; 64(6): 458-468, 2020 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-32221997

RESUMEN

HIV replication can be inhibited by CXCR5+ CD8 T cells (follicular cytotoxic T cell [TFC]) which transfer into B-cell follicles where latent HIV infection persists. However, how cytokines affect TFC remain unclear. Understanding which cytokines show the ability to affect TFC could be a key strategy toward curing HIV. Similar mechanisms could be used for the growth and transfer of TFCs and follicular helper T (TFH) cells; as a result, we hypothesized that cytokines IL-6, IL-21, and transforming growth factor-ß (TGF-ß), which are necessary for the differentiation of TFH cells, could also dictate the development of TFCs. In this work, lymph node mononuclear cells and peripheral blood mononuclear cells from HIV-infected individuals were cocultured with IL-6, IL-21, and TGF-ß. We then carried out T-cell receptor (TCR) repertoire analysis to compare the differences between CXCR5- and CXCR5+ CD8 T cells. Our results showed that the percentage and function of TFC can be enhanced by stimulation with TGF-ß. Besides, TGF-ß stimulation enhanced the diversity of TCR and complementarity-determining region 3 sequences. HIV DNA showed a negative correlation with TFC. The use of TGF-ß to promote the expression of CXCR5+ CD8 T cells could become a new treatment approach for curing HIV.


Asunto(s)
Infecciones por VIH/inmunología , Ganglios Linfáticos/inmunología , Subgrupos Linfocitarios/inmunología , Receptores CXCR5/inmunología , Linfocitos T Citotóxicos/inmunología , Linfocitos T Colaboradores-Inductores/inmunología , Factor de Crecimiento Transformador beta/fisiología , Adolescente , Adulto , Diferenciación Celular , Células Cultivadas , Técnicas de Cocultivo , VIH-1 , Humanos , Interleucina-6/inmunología , Interleucinas/inmunología , Ganglios Linfáticos/patología , Subgrupos Linfocitarios/patología , Masculino , Persona de Mediana Edad , Linfocitos T Citotóxicos/patología , Linfocitos T Colaboradores-Inductores/patología , Adulto Joven
16.
J Gene Med ; 19(5)2017 May.
Artículo en Inglés | MEDLINE | ID: mdl-28370835

RESUMEN

BACKGROUND: Poor endosomal release is a major barrier of polyplex-mediated gene transfection. Antimicrobial peptides (AMPs) are commonly used to improve polyethylenimine (PEI)-mediated gene transfection by increasing endosomal release. In the present study, we designed novel pH-sensitive peptides that highly enhance transfection efficiency compared to their parent peptides. METHODS: Two analogues of melittin (Mel) and RV-23 (RV) were synthesized by replacing the positively-charged residues in their sequences with glutamic acid residues. The pH-sensitive lysis ability of the peptides, the effect of the peptides on physicochemical characteristics, the intracellular trafficking, the transfection efficiency, and the cytotoxicity of the polyplexes were determined. RESULTS: The acidic peptides showed pH-sensitive lytic activity. The hemolytic activity of acidic peptides at pH 5.0 was higher than that at pH 7.4. The incorporation of acidic peptides did not affect the DNA binding ability of PEI but affected the physicochemical characteristics of the PEI/DNA polyplexes, which may be beneficial for endosomal release and gene transfection. The incorporation of acidic peptides into PEI/DNA polyplexes enhanced the PEI-mediated transfection efficiency corresponding to up to 42-fold higher luciferase activity compared to that of PEI alone. CONCLUSIONS: The results of the present study indicate that replacement of positively-charged residues with glutamic acid residues in the AMP sequence yields pH-sensitive peptides, which enhance the transfection efficiency of PEI/DNA polyplexes in various cell lines.


Asunto(s)
Antiinfecciosos/química , Péptidos/química , Polietileneimina/química , Antiinfecciosos/farmacología , Línea Celular , Línea Celular Tumoral , ADN/metabolismo , Endosomas/metabolismo , Técnicas de Transferencia de Gen , Células HeLa , Células Hep G2 , Células Endoteliales de la Vena Umbilical Humana , Humanos , Concentración de Iones de Hidrógeno , Meliteno/química , Péptidos/administración & dosificación , Péptidos/farmacología , Transfección/métodos
17.
Pharm Res ; 33(8): 1881-98, 2016 08.
Artículo en Inglés | MEDLINE | ID: mdl-27075873

RESUMEN

PURPOSE: To develop vincristine (VCR) and doxorubicin (DOX) co-encapsulated thermo-sensitive liposomes (VD-TSL) against drug resistance, with increased tumor inhibition rate and decreased system toxicity, improving drug targeting efficiency upon mild hyperthermia (HT) in solid tumor. METHODS: Based on similar physicochemical properties, VCR and DOX were co-loaded in TSL with pH gradient active loading method and characterized. The time-dependent drug release profiles at 37 and 42°C were assessed by HPLC. Then we analysed the phospholipids in filtrate after ultrafiltration and studied VD-TSL stability in mimic in vivo conditions and long-time storage conditions (4°C and -20°C). Cytotoxic effect was studied on PANC and sw-620 using MTT. Intracellular drug delivery was studied by confocal microscopy on HT-1080. In vivo imaging of TSL pharmacokinetic and biodistribution was performed on MCF-7 tumor-bearing nude mice. And therapeutic efficacy on these xenograft models were followed under HT. RESULTS: VD-TSL had excellent particle distribution (about 90 nm), high entrapment efficiency (>95%), obvious thermo-sensitive property, and good stability. MTT proved VD-TSL had strongest cell lethality compared with other formulations. Confocal microscopy demonstrated specific accumulation of drugs in tumor cells. In vivo imaging proved the targeting efficiency of TSL under hyperthermia. Then therapeutic efficacy revealed synergism of VCR and DOX co-loaded in TSL, together with HT. CONCLUSION: VD-TSL could increase drug efficacy and decrease system toxicity, by making good use of synergism of VCR and DOX, as well as high targeting efficiency of TSL.


Asunto(s)
Antibióticos Antineoplásicos/administración & dosificación , Doxorrubicina/administración & dosificación , Portadores de Fármacos/administración & dosificación , Sistemas de Liberación de Medicamentos/métodos , Vincristina/administración & dosificación , Animales , Antibióticos Antineoplásicos/química , Neoplasias de la Mama/tratamiento farmacológico , Fenómenos Químicos/efectos de los fármacos , Doxorrubicina/química , Portadores de Fármacos/química , Sinergismo Farmacológico , Femenino , Humanos , Liposomas , Células MCF-7 , Ratones , Ratones Desnudos , Temperatura , Distribución Tisular/efectos de los fármacos , Distribución Tisular/fisiología , Vincristina/química , Ensayos Antitumor por Modelo de Xenoinjerto/métodos
18.
Clin Transl Med ; 14(5): e1699, 2024 May.
Artículo en Inglés | MEDLINE | ID: mdl-38783408

RESUMEN

BACKGROUND: The gut is an important site for human immunodeficiency virus (HIV) infection and immune responses. The role of gut mucosal immune cells in immune restoration in patients infected with HIV undergoing antiretroviral therapy remains unclear. METHODS: Ileocytes, including 54 475 immune cells, were obtained from colonoscopic biopsies of five HIV-negative controls, nine immunological responders (IRs), and three immunological non-responders (INRs) and were analyzed using single-cell RNA sequencing. Immunohistochemical assays were performed for validation. The 16S rRNA gene was amplified using PCR in faecal samples to analyze faecal microbiota. Flow cytometry was used to analyze CD4+ T-cell counts and the activation of T cells. RESULTS: This study presents a global transcriptomic profile of the gut mucosal immune cells in patients infected with HIV. Compared with the IRs, the INRs exhibited a lower proportion of gut plasma cells, especially the IGKC+IgA+ plasma cell subpopulation. IGKC+IgA+ plasma cells were negatively associated with enriched f. Prevotellaceae the INRs and negatively correlated with the overactivation of T cells, but they were positively correlated with CD4+ T-cell counts. The INRs exhibited a higher proportion of B cells than the IRs. Follicular and memory B cells were significantly higher in the INRs. Reduced potential was observed in the differentiation of follicular or memory B cells into gut plasma cells in INRs. In addition, the receptor-ligand pairs CD74_MIF and CD74_COPA of memory B/ follicular helper T cells were significantly reduced in the INRs, which may hinder the differentiation of memory and follicular B cells into plasma cells. CONCLUSIONS: Our study shows that plasma cells are dysregulated in INRs and provides an extensive resource for deciphering the immune pathogenesis of HIV in INRs. KEY POINTS: An investigation was carried out at the single-cell-level to analyze gut mucosal immune cells alterations in PLWH after ART. B cells were significantly increased and plasma cells were significantly decreased in the INRs compared to the IRs and NCs. There are gaps in the transition from gut follicular or memory B cellsinto plasma cells in INRs.


Asunto(s)
Infecciones por VIH , Mucosa Intestinal , Células Plasmáticas , Humanos , Infecciones por VIH/inmunología , Infecciones por VIH/tratamiento farmacológico , Masculino , Células Plasmáticas/inmunología , Mucosa Intestinal/inmunología , Femenino , Adulto , Persona de Mediana Edad , Células B de Memoria/inmunología , Linfocitos B/inmunología
19.
Cancer Med ; 13(11): e7304, 2024 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-38826094

RESUMEN

BACKGROUND: The surge in omicron variants has caused nationwide breakthrough infections in mainland China since the December 2022. In this study, we report the neutralization profiles of serum samples from the patients with breast cancer and the patients with liver cancer who had contracted subvariant breakthrough infections. METHODS: In this real-world study, we enrolled 143 COVID-19-vaccinated (81 and 62 patients with breast and liver cancers) and 105 unvaccinated patients with cancer (58 and 47 patients with breast and liver cancers) after omicron infection. Anti-spike receptor binding domain (RBD) IgGs and 50% pseudovirus neutralization titer (pVNT50) for the preceding (wild type), circulating omicron (BA.4-BA.5, and BF.7), and new subvariants (XBB.1.5) were comprehensively analyzed. RESULTS: Patients with liver cancer receiving booster doses had higher levels of anti-spike RBD IgG against circulating omicron (BA.4-BA.5, and BF.7) and a novel subvariant (XBB.1.5) compared to patients with breast cancer after breakthrough infection. Additionally, all vaccinated patients produced higher neutralizing antibody titers against circulating omicron (BA.4-BA.5, and BF.7) compared to unvaccinated patients. However, the unvaccinated patients produced higher neutralizing antibody against XBB.1.5 than vaccinated patients after Omicron infection, with this trend being more pronounced in breast cancer than in liver cancer patients. Moreover, we found that there was no correlation between anti-spike RBD IgG against wildtype virus and the neutralizing antibody titer, but a positive correlation between anti-spike RBD IgG and the neutralizing antibody against XBB.1.5 was found in unvaccinated patients. CONCLUSION: Our study found that there may be differences in vaccine response and protective effect against COVID-19 infection in patients with liver and breast cancer. Therefore, we recommend that COVID-19 vaccine strategies should be optimized based on vaccine components and immunology profiles of different patients with cancer.


Asunto(s)
Anticuerpos Neutralizantes , Anticuerpos Antivirales , Neoplasias de la Mama , Vacunas contra la COVID-19 , COVID-19 , Neoplasias Hepáticas , SARS-CoV-2 , Humanos , Femenino , COVID-19/inmunología , COVID-19/epidemiología , COVID-19/prevención & control , COVID-19/virología , Neoplasias Hepáticas/virología , Neoplasias Hepáticas/inmunología , Neoplasias Hepáticas/epidemiología , Neoplasias de la Mama/inmunología , Neoplasias de la Mama/epidemiología , Neoplasias de la Mama/virología , SARS-CoV-2/inmunología , Anticuerpos Neutralizantes/sangre , Anticuerpos Neutralizantes/inmunología , Persona de Mediana Edad , Anticuerpos Antivirales/sangre , Anticuerpos Antivirales/inmunología , China/epidemiología , Vacunas contra la COVID-19/inmunología , Adulto , Anciano , Glicoproteína de la Espiga del Coronavirus/inmunología , Masculino , Brotes de Enfermedades , Inmunoglobulina G/sangre , Inmunoglobulina G/inmunología
20.
Emerg Microbes Infect ; 13(1): 2364744, 2024 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-38935839

RESUMEN

Recurrent opportunistic infections (OIs) in patients with severely immunosuppressed AIDS remain an unresolved medical challenge despite advancements in antiretroviral therapy (ART). To address this gap, we developed an HLA-mismatched allogeneic adoptive immune therapy (AAIT) specifically targeting this patient population. The safety and efficacy of this novel therapeutic approach were preliminarily confirmed in our phase 1 trial. Subsequently, a multicenter, open-label, controlled, phase 2a trial was conducted to evaluate the efficacy of AAIT in combination with ART compared with the conventional ART-only regimen. No difference in the incidence of adverse events (AEs) was observed between the two groups at the 96-week follow-up. AAIT treatment improved CD4+ T cell recovery at weeks 72 (P = 0.048) and 96 (P = 0.024) compared to the Control Group. Additionally, stratified analysis of patients in the AAIT Group showed that donor/recipient sex mismatch was significantly associated with the likelihood of patients achieving an immunological response (OR = 8.667; 95% CI, 2.010-37.377; P = 0.004). These findings suggest that AAIT serves as a promising adjunct therapy for improving the outcomes of patients with severely immunosuppressed AIDS. Further studies are needed to elucidate the immunological mechanisms underlying AAIT and identify the subpopulations that respond optimally to this therapeutic approach. This trial is registered at www.clinicaltrials.gov (NCT04098770).Trial registration: ClinicalTrials.gov identifier: NCT04098770.Trial registration: ClinicalTrials.gov identifier: NCT02651376.


Asunto(s)
Huésped Inmunocomprometido , Inmunoterapia Adoptiva , Humanos , Masculino , Femenino , Adulto , Persona de Mediana Edad , Inmunoterapia Adoptiva/métodos , Antígenos HLA/inmunología , Síndrome de Inmunodeficiencia Adquirida/inmunología , Síndrome de Inmunodeficiencia Adquirida/tratamiento farmacológico , Resultado del Tratamiento , Infecciones Oportunistas Relacionadas con el SIDA/inmunología , Infecciones Oportunistas Relacionadas con el SIDA/tratamiento farmacológico , Trasplante Homólogo , Linfocitos T CD4-Positivos/inmunología , Recuento de Linfocito CD4
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