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1.
MMWR Morb Mortal Wkly Rep ; 69(1): 1-5, 2020 Jan 10.
Artigo em Inglês | MEDLINE | ID: mdl-31917782

RESUMO

In May 2018, a study of birth defects in infants born to women with diagnosed human immunodeficiency virus (HIV) infection in Botswana reported an eightfold increased risk for neural tube defects (NTDs) among births with periconceptional exposure to antiretroviral therapy (ART) that included the integrase inhibitor dolutegravir (DTG) compared with other ART regimens (1). The World Health Organization* (WHO) and the U.S. Department of Health and Human Services† (HHS) promptly issued interim guidance limiting the initiation of DTG during early pregnancy and in women of childbearing age with HIV who desire pregnancy or are sexually active and not using effective contraception. On the basis of additional data, WHO now recommends DTG as a preferred treatment option for all populations, including women of childbearing age and pregnant women. Similarly, the U.S. recommendations currently state that DTG is a preferred antiretroviral drug throughout pregnancy (with provider-patient counseling) and as an alternative antiretroviral drug in women who are trying to conceive.§ Since 1981 and 1994, CDC has supported separate surveillance programs for HIV/acquired immunodeficiency syndrome (AIDS) (2) and birth defects (3) in state health departments. These two surveillance programs can inform public health programs and policy, linkage to care, and research activities. Because birth defects surveillance programs do not collect HIV status, and HIV surveillance programs do not routinely collect data on occurrence of birth defects, the related data have not been used by CDC to characterize birth defects in births to women with HIV. Data from these two programs were linked to estimate overall prevalence of NTDs and prevalence of NTDs in HIV-exposed pregnancies during 2013-2017 for 15 participating jurisdictions. Prevalence of NTDs in pregnancies among women with diagnosed HIV infection was 7.0 per 10,000 live births, similar to that among the general population in these 15 jurisdictions, and the U.S. estimate based on data from 24 states. Successful linking of data from birth defects and HIV/AIDS surveillance programs for pregnancies among women with diagnosed HIV infection suggests that similar data linkages might be used to characterize possible associations between maternal diseases or maternal use of medications, such as integrase strand transfer inhibitors used to manage HIV, and pregnancy outcomes. Although no difference in NTD prevalence in HIV-exposed pregnancies was found, data on the use of integrase strand transfer inhibitors in pregnancy are needed to understand the safety and risks of these drugs during pregnancy.


Assuntos
Infecções por HIV/diagnóstico , Defeitos do Tubo Neural/epidemiologia , Complicações Infecciosas na Gravidez/diagnóstico , Adolescente , Adulto , Antirretrovirais/efeitos adversos , Antirretrovirais/uso terapêutico , Feminino , Infecções por HIV/tratamento farmacológico , Humanos , Recém-Nascido , Gravidez , Complicações Infecciosas na Gravidez/tratamento farmacológico , Estados Unidos/epidemiologia , Adulto Jovem
2.
Chem Eng J ; 3962020 Sep 15.
Artigo em Inglês | MEDLINE | ID: mdl-32523422

RESUMO

Immunotherapy has been a promising candidate for cancer treatment. The combination of photothermal therapy (PTT) and immunotherapy have shown to cause tumor ablation and induce host immune response. However, this strategy is often hampered by a limited immune response and undesirable immunosuppression. In this work, we developed an immunologically modified nanoplatform, using ovalbumin (OVA)-coated PEGylated MnFe2O4 nanoparticles (NPs) loaded with R837 immunoadjuvant (R837-OVA-PEG-MnFe2O4 NPs) to synergize PTT and immunotherapy for the treatment of breast cancer. The designed R837-OVA-PEG-MnFe2O4 NPs are able to elicit significant immune responses in vitro and in vivo. MnFe2O4 NPs also allowed for a reduction of systemic immunosuppression through downregulation of M2-associated cytokines. More importantly, the R837-OVA-PEG-MnFe2O4 NPs under laser irradiation effectively inhibited tumor growth and prevented lung metastases, leading to a prolonged survival time and improved survival rate. In addition, the designed multitasking MnFe2O4 NPs showed as a good contrast agent for magnetic resonance (MR) imaging to detect orthotopic breast tumor in vivo. Our work provides a novel strategy for combined PTT and improved immunotherapy in the treatment of breast and other metastatic cancers.

3.
Sex Transm Dis ; 46(2): 139-142, 2019 02.
Artigo em Inglês | MEDLINE | ID: mdl-30169475

RESUMO

BACKGROUND: Louisiana has had the highest rates of congenital syphilis (CS) in the nation since 2012. Congenital syphilis case review boards were established statewide in 2016 to study CS cases and identify interventions. METHODS: We summarized the findings of CS review boards, assessed which cases were preventable by prenatal care providers, reviewed recommended interventions, and assessed subsequent improvement in provider practices. RESULTS: All 79 CS cases reported from January 2016 to July 2017 were reviewed by boards during August 2016 to August 2017. Twenty-six (33%) cases that could have been prevented by prenatal care providers had: lack of rescreening at 28 to 32 weeks (n = 15), lack of any screening (n = 5), treatment delay (n = 4), or incorrect interpretation of test results (n = 2). Twenty-one (27%) cases were possibly preventable by providers including: mother did not return for follow-up and treatment (n = 19), late third trimester reactive test with premature delivery (n = 1), or incomplete treatment and lack of follow-up by health department staff (n = 1). Thirty-two (40%) cases that were unlikely to be prevented by providers had: nonreactive test at 28-32 weeks then reactive test <30 days before delivery (n = 10), no prenatal care (n = 9), mother adequately treated, case by infant criteria (n = 8), first/second trimester nonreactive, reactive at preterm delivery (n = 4), or mother adequately treated, reinfected before delivery (n = 1). Providers were advised to adhere to CDC recommended syphilis screening and treatment protocols and rapidly report pregnant women with syphilis. Many providers changed their procedures. CONCLUSIONS: Congenital syphilis case review boards identified practices with inadequate screening, treatment, or reporting. Sharing these findings with providers changed practices and may prevent future cases.


Assuntos
Comitês de Ética em Pesquisa , Mães/estatística & dados numéricos , Complicações Infecciosas na Gravidez/prevenção & controle , Diagnóstico Pré-Natal/estatística & dados numéricos , Sífilis Congênita/prevenção & controle , Feminino , Humanos , Louisiana , Programas de Rastreamento , Gravidez , Complicações Infecciosas na Gravidez/microbiologia , Fatores de Risco , Sífilis Congênita/diagnóstico
4.
J Biol Chem ; 291(44): 23237-23247, 2016 10 28.
Artigo em Inglês | MEDLINE | ID: mdl-27646003

RESUMO

The thymus, an organ responsible for T cell development, is one of the more stress-sensitive tissues in the body. Stress, in the form of infections, radiation exposure, and steroids, impairs thymic epithelial cell (TEC) functions and induces the programmed cell death of immature thymocytes. MicroRNAs are small noncoding RNAs involved in tissue repair and homeostasis, with several supporting T cell development. We report that miR-205, an epithelial-specific miR, maintains thymopoiesis following inflammatory perturbations. Thus, the activation of diverse pattern recognition receptors in mice causes a more severe thymic hypoplasia and delayed T cell recovery when miR-205 is conditionally ablated in TECs. Gene expression comparisons in the TECs with/without miR-205 revealed a significant differential regulation of chemokine/chemokine receptor pathways, antigen processing components, and changes in the Wnt signaling system. This was partly a consequence of reduced expression of the transcriptional regulator of epithelial cell function, Forkhead Box N1 (Foxn1), and its two regulated targets, stem cell factor and ccl25, following stress. miR-205 mimics supplemented into miR-205-deficient fetal thymic organ cultures restored Foxn1 expression along with ccl25 and stem cell factor A number of putative targets of miR-205 were up-regulated in TECs lacking miR-205, consistent with an important role for this miR in supporting T cell development in response to stress.


Assuntos
Diferenciação Celular , Quimiocinas CC/metabolismo , Fatores de Transcrição Forkhead/genética , MicroRNAs/metabolismo , Fator de Células-Tronco/metabolismo , Linfócitos T/citologia , Linfócitos T/metabolismo , Animais , Células Cultivadas , Quimiocinas CC/genética , Feminino , Fatores de Transcrição Forkhead/metabolismo , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Knockout , MicroRNAs/genética , Fator de Células-Tronco/genética , Timócitos/citologia , Timócitos/metabolismo , Timo/citologia , Timo/crescimento & desenvolvimento , Timo/metabolismo
5.
Acta Biomater ; 175: 279-292, 2024 02.
Artigo em Inglês | MEDLINE | ID: mdl-38160856

RESUMO

Mucosal vaccinations for respiratory pathogens provide effective protection as they stimulate localized cellular and humoral immunities at the site of infection. Currently, the major limitation of intranasal vaccination is using effective adjuvants capable of withstanding the harsh environment imposed by the mucosa. Herein, we describe the efficacy of using a unique biopolymer, N-dihydrogalactochitosan (GC), as a nasal mucosal vaccine adjuvant against respiratory infections. Specifically, we mixed GC with recombinant SARS-CoV-2 trimeric spike (S) and nucleocapsid (NC) proteins to intranasally vaccinate K18-hACE2 transgenic mice, in comparison with Addavax (AV), an MF-59 equivalent. In contrast to AV, intranasal application of GC induces a robust, systemic antigen-specific antibody response and increases the number of T cells in the cervical lymph nodes. Moreover, GC+S+NC-vaccinated animals were largely resistant to the lethal SARS-CoV-2 challenge and experienced drastically reduced morbidity and mortality, with animal weights and behavior returning to normal 22 days post-infection. In contrast, animals intranasally vaccinated with AV+S+NC experienced severe weight loss, mortality, and respiratory distress, with none surviving beyond 6 days post-infection. Our findings demonstrate that GC can serve as a potent mucosal vaccine adjuvant against SARS-CoV-2 and potentially other respiratory viruses. STATEMENT OF SIGNIFICANCE: We demonstrated that a unique biopolymer, N-dihydrogalactochitosan (GC), was an effective nasal mucosal vaccine adjuvant against respiratory infections. Specifically, we mixed GC with recombinant SARS-CoV-2 trimeric spike (S) and nucleocapsid (NC) proteins to intranasally vaccinate K18-hACE2 transgenic mice, in comparison with Addavax (AV). In contrast to AV, GC induces a robust, systemic antigen-specific antibody response and increases the number of T cells in the cervical lymph nodes. About 90 % of the GC+S+NC-vaccinated animals survived the lethal SARS-CoV-2 challenge and remained healthy 22 days post-infection, while the AV+S+NC-vaccinated animals experienced severe weight loss and respiratory distress, and all died within 6 days post-infection. Our findings demonstrate that GC is a potent mucosal vaccine adjuvant against SARS-CoV-2 and potentially other respiratory viruses.


Assuntos
Acetilglucosamina/análogos & derivados , Vacinas contra Influenza , Melfalan , Polissorbatos , Síndrome do Desconforto Respiratório , Infecções Respiratórias , Esqualeno , gama-Globulinas , Camundongos , Animais , Proteínas Virais , Adjuvantes de Vacinas , Anticorpos Antivirais , Adjuvantes Imunológicos/farmacologia , Proteínas Recombinantes/farmacologia , Infecções Respiratórias/prevenção & controle , Mucosa , Camundongos Transgênicos , Biopolímeros , Redução de Peso
6.
bioRxiv ; 2024 Jan 26.
Artigo em Inglês | MEDLINE | ID: mdl-38328121

RESUMO

T-cell immunoglobin and mucin domain protein-1 (TIM-1) mediates entry of Chikungunya virus (CHIKV) into some mammalian cells through the interaction with envelope phospholipids. While this interaction enhances entry, TIM has been shown to tether newly formed HIV and Ebola virus particles, limiting their efficient release. In this study, we investigate the ability of surface receptors such as TIM-1 to sequester newly budded virions on the surface of infected cells. We established a luminescence reporter system to produce Chikungunya viral particles that integrate nano-luciferase and easily quantify viral particles. We found that TIM-1 on the surface of host cells significantly reduced CHIKV release efficiency in comparison to other entry factors. Removal of cell surface TIM-1 through direct cellular knock-out or altering the cellular lipid distribution enhanced CHIKV release. Over the course of infection, CHIKV was able to counteract the tethering effect by gradually decreasing the surface levels of TIM-1 in a process that appears to be mediated by the nonstructural protein 2. This study highlights the importance of phosphatidylserine receptors in mediating not only the entry of CHIKV but also its release and could aid in developing cell lines capable of enhanced vaccine production.

7.
Clin Immunol ; 147(1): 11-22, 2013 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-23454892

RESUMO

Patients with 22q11.2 deletion syndrome have heterogeneous clinical presentations including immunodeficiency, cardiac anomalies, and hypocalcemia. The syndrome arises from hemizygous deletions of up to 3Mb on chromosome 22q11.2, a region that contains 60 genes and 4 microRNAs. MicroRNAs are important post-transcriptional regulators of gene expression, with mutations in several microRNAs causal to specific human diseases. We characterized the microRNA expression patterns in the peripheral blood of patients with 22q11.2 deletion syndrome (n=31) compared to normal controls (n=22). Eighteen microRNAs had a statistically significant differential expression (p<0.05), with miR-185 expressed at 0.4× normal levels. The 22q11.2 deletion syndrome cohort exhibited microRNA expression hyper-variability and group dysregulation. Selected microRNAs distinguished patients with cardiac anomalies, hypocalcemia, and/or low circulating T cell counts. In summary, microRNA profiling of chromosome 22q11.2 deletion syndrome/DiGeorge patients revealed a signature microRNA expression pattern distinct from normal controls with clinical relevance.


Assuntos
Síndrome de DiGeorge/genética , Perfilação da Expressão Gênica , MicroRNAs/genética , Análise de Sequência com Séries de Oligonucleotídeos/métodos , Adolescente , Criança , Pré-Escolar , Deleção Cromossômica , Cromossomos Humanos Par 22/genética , Estudos de Coortes , Feminino , Cardiopatias Congênitas/genética , Humanos , Hipocalcemia/genética , Lactente , Contagem de Linfócitos , Masculino , Linfócitos T/metabolismo
8.
Public Health Rep ; 138(2_suppl): 48S-55S, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-36734193

RESUMO

OBJECTIVE: To better understand health experiences among Two Spirit and lesbian, gay, bisexual, transgender, and queer and questioning (LGBTQ+) American Indian/Alaska Native (AI/AN) people, we examined experiences with access to health care of 223 AI/AN Two Spirit and LGBTQ+ people. METHODS: Participants of the Pride and Connectedness 2020 survey, conducted through the Northwest Portland Area Indian Health Board, were asked about barriers to seeking and accessing care through a 10-question scale. We compared cisgender and gender-diverse participant demographic and scale responses to explore potential differences based on gender identity using the Pearson χ2 test of independence and ordinal logistic regression, respectively. RESULTS: Both cisgender and gender-diverse participants experienced at least some difficulties accessing health care. Finances, lack of psychologists/other mental health support, and lack of psychological support groups for Two Spirit and LGBTQ+ communities were the top 3 barriers to care experienced by all participants (84%, 82%, and 80%, respectively). Compared with cisgender participants, gender-diverse participants were more likely to report difficulties accessing care for nearly all questions on the 10-question scale and nearly 3 times more likely to report fear of being mistreated within the health care system based on their gender identity (adjusted odds ratio = 2.9; 95% CI, 1.8-4.9; P < .001). CONCLUSIONS: Increased access to mental health services and improved health care provider training that focuses on culturally relevant and gender-affirming practices would benefit the health and well-being of AI/AN people who identify as Two Spirit and LGBTQ+.


Assuntos
Minorias Sexuais e de Gênero , Humanos , Masculino , Feminino , Identidade de Gênero , Indígena Americano ou Nativo do Alasca , Acessibilidade aos Serviços de Saúde
9.
J Innov Opt Health Sci ; 16(3)2023 May.
Artigo em Inglês | MEDLINE | ID: mdl-38550850

RESUMO

The tumor microenvironment (TME) promotes pro-tumor and anti-inflammatory metabolisms and suppresses the host immune system. It prevents immune cells from fighting against cancer effectively, resulting in limited efficacy of many current cancer treatment modalities. Different therapies aim to overcome the immunosuppressive TME by combining various approaches to synergize their effects for enhanced anti-tumor activity and augmented stimulation of the immune system. Immunotherapy has become a major therapeutic strategy because it unleashes the power of the immune system by activating, enhancing, and directing immune responses to prevent, control, and eliminate cancer. Phototherapy uses light irradiation to induce tumor cell death through photothermal, photochemical, and photo-immunological interactions. Phototherapy induces tumor immunogenic cell death, which is a precursor and enhancer for anti-tumor immunity. However, phototherapy alone has limited effects on long-term and systemic anti-tumor immune responses. Phototherapy can be combined with immunotherapy to improve the tumoricidal effect by killing target tumor cells, enhancing immune cell infiltration in tumors, and rewiring pathways in the TME from anti-inflammatory to pro-inflammatory. Phototherapy-enhanced immunotherapy triggers effective cooperation between innate and adaptive immunities, specifically targeting the tumor cells, whether they are localized or distant. Herein, the successes and limitations of phototherapy combined with other cancer treatment modalities will be discussed. Specifically, we will review the synergistic effects of phototherapy combined with different cancer therapies on tumor elimination and remodeling of the immunosuppressive TME. Overall, phototherapy, in combination with other therapeutic modalities, can establish anti-tumor pro-inflammatory phenotypes in activated tumor-infiltrating T cells and B cells and activate systemic anti-tumor immune responses.

10.
PLoS One ; 18(8): e0289139, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37552656

RESUMO

The rapid emergence and global dissemination of SARS-CoV-2 that causes COVID-19 continues to cause an unprecedented global health burden resulting in nearly 7 million deaths. While multiple vaccine countermeasures have been approved for emergency use, additional treatments are still needed due to sluggish vaccine rollout, vaccine hesitancy, and inefficient vaccine-mediated protection. Immunoadjuvant compounds delivered intranasally can guide non-specific innate immune responses during the critical early stages of viral replication, reducing morbidity and mortality. N-dihydrogalactochitosan (GC) is a novel mucoadhesive immunostimulatory polymer of ß-0-4-linked N-acetylglucosamine that is solubilized by the conjugation of galactose glycans with current applications as a cancer immunotherapeutic. We tested GC as a potential countermeasure for COVID-19. GC was well-tolerated and did not produce histopathologic lesions in the mouse lung. GC administered intranasally before and after SARS-CoV-2 exposure diminished morbidity and mortality in humanized ACE2 receptor expressing mice by up to 75% and reduced infectious virus levels in the upper airway. Fluorescent labeling of GC shows that it is confined to the lumen or superficial mucosa of the nasal cavity, without involvement of adjacent or deeper tissues. Our findings demonstrate a new application for soluble immunoadjuvants such as GC for preventing disease associated with SARS-CoV-2 and may be particularly attractive to persons who are needle-averse.


Assuntos
COVID-19 , SARS-CoV-2 , Camundongos , Animais , Acetilglucosamina , Replicação Viral
11.
bioRxiv ; 2023 May 03.
Artigo em Inglês | MEDLINE | ID: mdl-37205468

RESUMO

Rationale: Natural killer (NK) cells provide protective anti-cancer immunity. However, the cancer therapy induced activation gene signatures and pathways in NK cells remain unclear. Methods: We applied a novel localized ablative immunotherapy (LAIT) by synergizing photothermal therapy (PTT) with intra-tumor delivering of the immunostimulant N-dihydrogalactochitosan (GC), to treat breast cancer using a mammary tumor virus-polyoma middle tumor-antigen (MMTV-PyMT) mouse model. We performed single-cell RNA sequencing (scRNAseq) analysis to unveil the cellular heterogeneity and compare the transcriptional alterations induced by PTT, GC, and LAIT in NK cells within the tumor microenvironment (TME). Results: ScRNAseq showed that NK subtypes, including cycling, activated, interferon-stimulated, and cytotoxic NK cells. Trajectory analysis revealed a route toward activation and cytotoxicity following pseudotime progression. Both GC and LAIT elevated gene expression associated with NK cell activation, cytolytic effectors, activating receptors, IFN pathway components, and cytokines/chemokines in NK subtypes. Single-cell transcriptomics analysis using immune checkpoint inhibitor (ICI)-treated animal and human samples revealed that ICI-induced NK activation and cytotoxicity across several cancer types. Furthermore, ICI-induced NK gene signatures were also induced by LAIT treatment. We also discovered that several types of cancer patients had significantly longer overall survival when they had higher expression of genes in NK cells that were also specifically upregulated by LAIT. Conclusion: Our findings show for the first time that LAIT activates cytotoxicity in NK cells and the upregulated genes positively correlate with beneficial clinical outcomes for cancer patients. More importantly, our results further establish the correlation between the effects of LAIT and ICI on NK cells, hence expanding our understanding of mechanism of LAIT in remodeling TME and shedding light on the potentials of NK cell activation and anti-tumor cytotoxic functions in clinical applications.

12.
Appl Environ Microbiol ; 78(19): 6829-37, 2012 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-22820329

RESUMO

Mycobacterial shuttle vectors contain dual origins of replication for growth in both Escherichia coli and mycobacteria. One such vector, pSUM36, was re-engineered for high-level protein expression in diverse bacterial species. The modified vector (pSUM-kan-MCS2) enabled green fluorescent protein expression in E. coli, Mycobacterium smegmatis, and M. avium at levels up to 50-fold higher than that detected with the parental vector, which was originally developed with a lacZα promoter. This high-level fluorescent protein expression allowed easy visualization of M. smegmatis and M. avium in infected macrophages. The M. tuberculosis gene esat-6 was cloned in place of the green fluorescence protein gene (gfp) to determine the impact of ESAT-6 on the innate inflammatory response. The modified vector (pSUM-kan-MCS2) yielded high levels of ESAT-6 expression in M. smegmatis. The ability of ESAT-6 to suppress innate inflammatory pathways was assayed with a novel macrophage reporter cell line, designed with an interleukin-6 (IL-6) promoter-driven GFP cassette. This stable cell line fluoresces in response to diverse mycobacterial strains and stimuli, such as lipopolysaccharide. M. smegmatis clones expressing high levels of ESAT-6 failed to attenuate IL-6-driven GFP expression. Pure ESAT-6, produced in E. coli, was insufficient to suppress a strong inflammatory response elicited by M. smegmatis or lipopolysaccharide, with ESAT-6 itself directly activating the IL-6 pathway. In summary, a pSUM-protein expression vector and a mammalian IL-6 reporter cell line provide new tools for understanding the pathogenic mechanisms deployed by various mycobacterial species.


Assuntos
Expressão Gênica , Vetores Genéticos , Genética Microbiana/métodos , Macrófagos/microbiologia , Biologia Molecular/métodos , Mycobacterium/genética , Antígenos de Bactérias/biossíntese , Antígenos de Bactérias/genética , Proteínas de Bactérias/biossíntese , Proteínas de Bactérias/genética , Escherichia coli/genética , Fluorescência , Genes Reporter , Proteínas de Fluorescência Verde/biossíntese , Proteínas de Fluorescência Verde/genética , Evasão da Resposta Imune , Tolerância Imunológica , Mycobacterium/patogenicidade , Proteínas Recombinantes/biossíntese , Proteínas Recombinantes/genética , Fatores de Virulência/biossíntese , Fatores de Virulência/genética
13.
Clin Transl Med ; 12(7): e937, 2022 07.
Artigo em Inglês | MEDLINE | ID: mdl-35808806

RESUMO

BACKGROUND: Metastatic breast cancer poses great challenge in cancer treatment. N-dihydrogalactochitosan (GC) is a novel immunoadjuvant that stimulates systemic immune responses when administered intratumourally following local tumour ablation. A combination of photothermal therapy (PTT) and GC, referred to as localized ablative immunotherapy (LAIT), extended animal survival and generates an activated B cell phenotype in MMTV-PyMT mouse mammary tumour microenvironment (TME). However, how T cell populations respond to LAIT remains to be elucidated. METHODS: Using depletion antibodies, we studied the contributions of CD8+ and CD4+ T cells to the therapeutic effect of LAIT. Using single-cell RNA-sequencing (scRNAseq), we analysed tumour-infiltrating T cell heterogeneity and dissected their transcriptomes upon treatments of PTT, GC, and LAIT (PTT+GC). RESULTS: Loss of CD8+ T cells after LAIT abrogated the therapeutic benefits of LAIT. Ten days after treatment, proportions of CD8+ and CD4+ T cells in untreated TME were 19.2% and 23.0%, respectively. Upon LAIT, both proportions were increased to 25.5% and 36.2%, respectively. In particular, LAIT increased the proportions of naïve and memory cells from a resting state to an activated state. LAIT consistently induced the expression of co-stimulatory molecules, type I IFN responsive genes, and a series of antitumor cytokines, Ifng, Tnf, Il1, and Il17 in CD8+ and CD4+ T cells. LAIT also induced immune checkpoints Pdcd1, Ctla4, and Lag3 expression, consistent with T cell activation. Relevant to clinical translation, LAIT also upregulated genes in CD8+ and CD4+ T cells that positively correlated with extended survival of breast cancer patients. CONCLUSIONS: Overall, our results reveal that LAIT prompts immunological remodelling of T cells by inducing broad proinflammatory responses and inhibiting suppressive signalling to drive antitumour immunity.


Assuntos
Linfócitos T CD8-Positivos , Neoplasias , Acetilglucosamina/análogos & derivados , Adjuvantes Imunológicos/farmacologia , Animais , Camundongos , Análise de Sequência de RNA , Microambiente Tumoral
14.
Theranostics ; 12(2): 639-656, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-34976205

RESUMO

Rationale: B cells have emerged as key regulators in protective cancer immunity. However, the activation pathways induced in B cells during effective immunotherapy are not well understood. Methods: We used a novel localized ablative immunotherapy (LAIT), combining photothermal therapy (PTT) with intra-tumor delivery of the immunostimulant N-dihydrogalactochitosan (GC), to treat mice bearing mouse mammary tumor virus-polyoma middle tumor-antigen (MMTV-PyMT). We used single-cell RNA sequencing to compare the transcriptional changes induced by PTT, GC and PTT+GC in B cells within the tumor microenvironment (TME). Results: LAIT significantly increased survival in the tumor-bearing mice, compared to the treatment by PTT and GC alone. We found that PTT, GC and PTT+GC increased the proportion of tumor-infiltrating B cells and induced gene expression signatures associated with B cell activation. Both GC and PTT+GC elevated gene expression associated with antigen presentation, whereas GC elevated transcripts that regulate B cell activation and GTPase function and PTT+GC induced interferon response genes. Trajectory analysis, where B cells were organized according to pseudotime progression, revealed that both GC and PTT+GC induced the differentiation of B cells from a resting state towards an effector phenotype. The analyses confirmed upregulated interferon signatures in the differentiated tumor-infiltrating B cells following treatment by PTT+GC but not by GC. We also observed that breast cancer patients had significantly longer survival time if they had elevated expression of genes in B cells that were induced by PTT+GC therapy in the mouse tumors. Conclusion: Our findings show that the combination of local ablation and local application of immunostimulant initiates the activation of interferon signatures and antigen-presentation in B cells which is associated with positive clinical outcomes for breast cancer. These findings broaden our understanding of LAIT's regulatory roles in remodeling TME and shed light on the potentials of B cell activation in clinical applications.


Assuntos
Apresentação de Antígeno , Linfócitos B/imunologia , Imunoterapia , Interferons/metabolismo , Neoplasias Mamárias Experimentais/imunologia , Animais , Linfócitos B/metabolismo , Feminino , Regulação Neoplásica da Expressão Gênica , Linfócitos do Interstício Tumoral/imunologia , Linfócitos do Interstício Tumoral/metabolismo , Neoplasias Mamárias Experimentais/genética , Neoplasias Mamárias Experimentais/mortalidade , Neoplasias Mamárias Experimentais/terapia , Camundongos , Transcriptoma
15.
J Immunother Cancer ; 10(10)2022 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-36253002

RESUMO

BACKGROUND: Localized ablative immunotherapies hold great promise in stimulating antitumor immunity to treat metastatic and poorly immunogenic tumors. Tumor ablation is well known to release tumor antigens and danger-associated molecular patterns to stimulate T-cell immunity, but its immune stimulating effect is limited, particularly against metastatic tumors. METHODS: In this study, we combined photothermal therapy with a potent immune stimulant, N-dihydrogalactochitosan, to create a local ablative immunotherapy which we refer to as laser immunotherapy (LIT). Mice bearing B16-F10 tumors were treated with LIT when the tumors reached 0.5 cm3 and were monitored for survival, T-cell activation, and the ability to resist tumor rechallenge. RESULTS: We found that LIT stimulated a stronger and more consistent antitumor T-cell response to the immunologically 'cold' B16-F10 melanoma tumors and conferred a long-term antitumor memory on tumor rechallenge. Furthermore, we discovered that LIT generated de novo CD8+ T-cell responses that strongly correlated with animal survival and tumor rejection. CONCLUSION: In summary, our findings demonstrate that LIT enhances the activation of T cells and drives de novo antitumor T-cell responses. The data presented herein suggests that localized ablative immunotherapies have great potential to synergize with immune checkpoint therapies to enhance its efficacy, resulting in improved antitumor immunity.


Assuntos
Linfócitos T CD8-Positivos , Melanoma Experimental , Acetilglucosamina/análogos & derivados , Animais , Antígenos de Neoplasias , Imunoterapia/métodos , Camundongos , Camundongos Endogâmicos C57BL
16.
Acta Biomater ; 138: 453-462, 2022 01 15.
Artigo em Inglês | MEDLINE | ID: mdl-34757232

RESUMO

Pancreatic cancer (PC) is the most lethal malignancy due to its high metastatic ability and poor drug permeability. Here, a synergized interventional photothermal-immunotherapy strategy was developed with imaging guidance and temperature monitoring by magnetic resonance imaging (MRI) technique, for the local treatment of metastatic PC. A tumor microenvironment (TME)-responsive nanoplatform was fabricated via coating of DSPE-PEG and indocyanine green (ICG) onto imiquimod (IMQ) loaded amorphous iron oxide nanoparticles (IONs). This unique nanoplatform, IMQ@IONs/ICG, served as a contrast agent for MRI, a drug delivery vehicle for IMQ and ICG, and a catalyst for TME modulation. The biodegradable IMQ@IONs/ICG was also non-toxic, and improved the penetration of the loaded drugs in PC to maximize thermal ablation of the tumor and minimize damage to the surrounding healthy tissue. For the treatment of aggressive, metastatic Panc02-H7 pancreatic tumors in mice, ION-assisted MRI was employed to guide the administration of interventional photothermal therapy (IPTT) and monitor the temperature distribution in target tumor and surrounding tissue during treatment. The local IPTT treatment induced in situ immunogenic cell death (ICD), and, in combination with released IMQ, triggered a strong antitumor immunity, leading to decreased metastases and increased CD8+ in spleen and tumors. With precise local treatment and monitoring, treated primary tumors were completely eradicated, mesentery metastases were dramatically reduced, and the survival time was significantly prolonged, without damage to normal tissue and systemic autoimmunity. Overall, this synergistic strategy represents a promising approach to treat PC with significant potential for clinical applications. STATEMENT OF SIGNIFICANCE: Pancreatic cancer (PC) is one of the most lethal malignancies because it is non-permeable to drugs and highly metastatic. In this study, we designed a tumor microenvironment-responsive amorphous iron oxide nanoplatform (ION) to co-deliver photothermal agent (ICG) and toll-like-receptor-7 agonist (IMQ). This biodegradable nanoplatform IMQ@IONs/ICG improved the penetration of the loaded drugs in pancreatic tumor. With MR imaging guidance and temperature monitoring, the precise interventional photothermal therapy on mouse Panc02-H7 orthotopic tumors releases tumor antigens to initiate tumor-special immune responses, amplified by the released IMQ. Our results demonstrate that IMQ@IONs/ICG overcomes the obstacle of drug delivery to pancreatic tumors, and when combined with photothermal therapy, induces a systemic antitumor immunity to control metastatic tumors.


Assuntos
Nanopartículas , Neoplasias Pancreáticas , Animais , Linhagem Celular Tumoral , Compostos Férricos , Imunoterapia , Verde de Indocianina , Camundongos , Neoplasias Pancreáticas/terapia , Fototerapia , Terapia Fototérmica , Microambiente Tumoral
17.
Mucosal Immunol ; 14(1): 68-79, 2021 01.
Artigo em Inglês | MEDLINE | ID: mdl-32483197

RESUMO

Thymocytes bearing αß T cell receptors (TCRαß) with high affinity for self-peptide-MHC complexes undergo negative selection or are diverted to alternate T cell lineages, a process termed agonist selection. Among thymocytes bearing TCRs restricted to MHC class I, agonist selection can lead to the development of precursors that can home to the gut and give rise to CD8αα-expressing intraepithelial lymphocytes (CD8αα IELs). The factors that influence the choice between negative selection versus CD8αα IEL development remain largely unknown. Using a synchronized thymic tissue slice model that supports both negative selection and CD8αα IEL development, we show that the affinity threshold for CD8αα IEL development is higher than for negative selection. We also investigate the impact of peptide presenting cells and cytokines, and the migration patterns associated with these alternative cell fates. Our data highlight the roles of TCR affinity and the thymic microenvironments on T cell fate.


Assuntos
Linfócitos T CD8-Positivos/imunologia , Linfócitos T CD8-Positivos/metabolismo , Seleção Clonal Mediada por Antígeno , Linfócitos Intraepiteliais/imunologia , Linfócitos Intraepiteliais/metabolismo , Receptores de Antígenos de Linfócitos T alfa-beta/metabolismo , Timo/imunologia , Timo/metabolismo , Linfócitos T CD8-Positivos/citologia , Microambiente Celular , Seleção Clonal Mediada por Antígeno/genética , Seleção Clonal Mediada por Antígeno/imunologia , Antígenos de Histocompatibilidade/química , Antígenos de Histocompatibilidade/genética , Antígenos de Histocompatibilidade/imunologia , Linfócitos Intraepiteliais/citologia , Peptídeos/imunologia , Timo/citologia
18.
Elife ; 102021 04 22.
Artigo em Inglês | MEDLINE | ID: mdl-33884954

RESUMO

Functional tuning of T cells based on their degree of self-reactivity is established during positive selection in the thymus, although how positive selection differs for thymocytes with relatively low versus high self-reactivity is unclear. In addition, preselection thymocytes are highly sensitive to low-affinity ligands, but the mechanism underlying their enhanced T cell receptor (TCR) sensitivity is not fully understood. Here we show that murine thymocytes with low self-reactivity experience briefer TCR signals and complete positive selection more slowly than those with high self-reactivity. Additionally, we provide evidence that cells with low self-reactivity retain a preselection gene expression signature as they mature, including genes previously implicated in modulating TCR sensitivity and a novel group of ion channel genes. Our results imply that thymocytes with low self-reactivity downregulate TCR sensitivity more slowly during positive selection, and associate membrane ion channel expression with thymocyte self-reactivity and progress through positive selection.


Assuntos
Diferenciação Celular , Antígenos de Histocompatibilidade Classe I/imunologia , Receptores de Antígenos de Linfócitos T/imunologia , Tolerância a Antígenos Próprios , Timócitos/imunologia , Timo/imunologia , Animais , Linhagem da Célula , Regulação da Expressão Gênica , Antígenos de Histocompatibilidade Classe I/metabolismo , Canais Iônicos/genética , Canais Iônicos/metabolismo , Cinética , Camundongos Endogâmicos C57BL , Camundongos Transgênicos , Fenótipo , Receptores de Antígenos de Linfócitos T/genética , Receptores de Antígenos de Linfócitos T/metabolismo , Transdução de Sinais , Timócitos/metabolismo , Timo/crescimento & desenvolvimento , Timo/metabolismo , Transcriptoma
19.
J Nat Prod ; 73(5): 942-8, 2010 May 28.
Artigo em Inglês | MEDLINE | ID: mdl-20450206

RESUMO

Chemical epigenetic manipulation of Penicillium citreonigrum led to profound changes in the secondary metabolite profile of its guttate. While guttate from control cultures exhibited a relatively simple assemblage of secondary metabolites, the guttate collected from cultures treated with 50 muM 5-azacytidine (a DNA methyltransferase inhibitor) was highly enriched in compounds representing at least three distinct biosynthetic families. The metabolites obtained from the fungus included six azaphilones (sclerotiorin (1), sclerotioramine (6), ochrephilone (2), dechloroisochromophilone III (3), dechloroisochromophilone IV (4), and 6-((3E,5E)-5,7-dimethyl-2-methylenenona-3,5-dienyl)-2,4-dihydroxy-3-methylbenzaldehyde (5)), pencolide (7), and two new meroterpenes (atlantinones A and B (9 and 10, respectively)). While pencolide was detected in the exudates of both control and 5-azacytidine-treated cultures, all of the other natural products were found exclusively in the guttates of the epigenetically modified fungus. All of the metabolites from the P. citreonigrum guttate were tested for antimicrobial activity in a disk diffusion assay. Both sclerotiorin and sclerotioramine caused modest inhibition of Staphylococcus epidermidis growth; however, only sclerotioramine was active against a panel of Candida strains.


Assuntos
Compostos Heterocíclicos/isolamento & purificação , Cetonas/isolamento & purificação , Penicillium/química , Penicillium/genética , Azacitidina/farmacologia , Benzopiranos/química , Benzopiranos/isolamento & purificação , Candida/efeitos dos fármacos , Metilases de Modificação do DNA/antagonistas & inibidores , Compostos Heterocíclicos/química , Compostos Heterocíclicos/farmacologia , Cetonas/química , Cetonas/farmacologia , Testes de Sensibilidade Microbiana , Estrutura Molecular , Penicillium/efeitos dos fármacos , Penicillium/metabolismo , Pigmentos Biológicos/química , Pigmentos Biológicos/isolamento & purificação , Solo , Staphylococcus epidermidis/efeitos dos fármacos , Terpenos/química , Terpenos/isolamento & purificação
20.
Oncoimmunology ; 9(1): 1685300, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32002300

RESUMO

Cancer immunotherapy continues to make headway as a treatment for advanced stage tumors, revealing an urgent need to understand the fundamentals of anti-tumor immune responses. Noteworthy is a scarcity of data pertaining to the breadth and specificity of tumor-specific T cell responses in metastatic breast cancer. Autochthonous transgenic models of breast cancer display spontaneous metastasis in the FVB/NJ mouse strain, yet a lack of knowledge regarding tumor-bound MHC/peptide immune epitopes in this mouse model limits the characterization of tumor-specific T cell responses, and the mechanisms that regulate T cell responses in the metastatic setting. We recently generated the NetH2pan prediction tool for murine class I MHC ligands by building an FVB/NJ H-2q ligand database and combining it with public information from six other murine MHC alleles. Here, we deployed NetH2pan in combination with an advanced proteomics workflow to identify immunogenic T cell epitopes in the MMTV-PyMT transgenic model for metastatic breast cancer. Five unique MHC I/PyMT epitopes were identified. These tumor-specific epitopes were confirmed to be presented by the class I MHC of primary MMTV-PyMT tumors and their T cell immunogenicity was validated. Vaccination using a DNA construct encoding a truncated PyMT protein generated CD8 + T cell responses to these MHC class I/peptide complexes and prevented tumor development. In sum, we have established an MHC-ligand discovery pipeline in FVB/NJ mice, identified and tracked H-2Dq/PyMT neoantigen-specific T cells, and developed a vaccine that prevents tumor development in this metastatic model of breast cancer.


Assuntos
Antígenos de Neoplasias , Neoplasias da Mama , Animais , Neoplasias da Mama/genética , Modelos Animais de Doenças , Epitopos de Linfócito T/genética , Feminino , Humanos , Camundongos , Camundongos Endogâmicos , Metástase Neoplásica
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