ORCID Profile
0000-0001-5022-4692
Current Organisation
Commissariat à l'Énergie Atomique et aux Énergies Alternatives
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Publisher: Research Square Platform LLC
Date: 07-02-2023
DOI: 10.21203/RS.3.RS-2521252/V1
Abstract: The establishment of latent herpes simplex virus 1 (HSV-1) infection is controlled by promyelocytic leukemia nuclear bodies (PML NBs). Viral genomes are recruited to PML NBs structures and chromatinized by repressive H3.3K9me3 modified H3.3 histone variant to form viral DNA-containing PML-NBs (vDCP NBs). Exactly how this occurs is unclear. Here we identify an essential role for the HUSH complex and its SETDB1 and MORC2 effectors in the establishment and maintenance of latent herpes simplex virus 1 (HSV-1) infection. We show that the formation of repressive heterochromatin is dependent on HUSH, SETDB1 and MORC2 in vDCP NBs, and depletion of any of these components prior to viral infection decreases H3K9me3 levels over latent/quiescent HSV-1 genomes. Once latency is established, depletion of HUSH, SETDB1, or MORC2 by shRNAs or the HIV-2 Vpx protein, induces the reactivation of HSV-1 in infected primary human fibroblasts as well as human induced pluripotent stem cell-derived sensory neurons (hiPSDN). Our data demonstrate the potent antiviral restriction activity of the HUSH/SETDB1/ MORC2 complex to a non-integrated human herpesvirus, its close association with PML NBs, and introduces a new target for anti-herpesvirus therapy.
Publisher: Springer Science and Business Media LLC
Date: 19-05-2022
DOI: 10.1038/S41598-022-12597-4
Abstract: Primary infection with herpes simplex type 1 (HSV-1) occurring around the mouth and nose switches rapidly to lifelong latent infection in sensitive trigeminal ganglia (TG) neurons. Sporadic reactivation of these latent reservoirs later in life is the cause of acute infections of the corneal epithelium, which can cause potentially blinding herpes simplex keratitis (HSK). There is no effective vaccine to protect against HSK, and antiviral drugs provide only partial protection against recurrences. We previously engendered an acute disease-free, non-reactivating latent state in mice when challenged with virulent HSV-1 in orofacial mucosa, by priming with non-neurovirulent HSV-1 (TK del ) before the challenge. Herein, we define the local immune infiltration and inflammatory chemokine production changes after virulent HSV-1 challenge, which were elicited by TK del prime. Heightened immunosurveillance before virulent challenge, and early enhanced lymphocyte-enriched infiltration of the challenged lip were induced, which corresponded to attenuation of inflammation in the TG and enhanced viral control. Furthermore, classical latent-phase T cell persistence around latent HSV-1 reservoirs were severely reduced. These findings identify the immune processes that are likely to be responsible for establishing non-reactivating latent HSV-1 reservoirs. Stopping reactivation is essential for development of efficient vaccine strategies against HSV-1.
Publisher: Elsevier BV
Date: 04-2018
Publisher: Frontiers Media SA
Date: 30-10-2017
Publisher: Elsevier BV
Date: 02-2023
Publisher: Springer Science and Business Media LLC
Date: 11-06-2010
DOI: 10.1038/CGT.2010.27
Abstract: We describe the construction and evaluation of a recombinant hepatitis B surface antigen (HBsAg)-vectored DNA vaccine encoding the E7 and E6 tumor-associated oncoproteins of human papillomavirus (HPV) type 16. We show the induction of effector and memory cytotoxic T lymphocyte responses to E7 and E6 class I-restricted epitopes after a single immunization, which were associated with tumor prevention and therapy. The findings vindicate the use of a HBsAg-based DNA vaccine as a vehicle to elicit responses to co-encoded tumor antigens, and have specific implications for the development of a therapeutic vaccine for HPV-associated squamous carcinomas.
Publisher: MDPI AG
Date: 02-11-2020
Abstract: Ocular manifestations are a feature of West Nile virus infection. They mostly occur in association with severe neuroinvasive disease. Linear chorioretinitis is suggestive of the diagnosis and may raise diagnostic suspicion when associated with evocative systemic signs, and in an epidemic context. Various other less specific inflammatory ocular manifestations have been reported, including anterior uveitis, occlusive retinal vasculitis, optic neuritis, and diplopia. The pathophysiology of ocular disease remains unclear, but it reflects the neuroinvasiveness of the disease. Although ocular involvement most often resolves without visual sequelae, some patients may have permanent loss of vision, adding to the need for the development of a specific treatment and/or vaccines.
Publisher: Elsevier BV
Date: 02-2018
DOI: 10.1016/J.JIM.2018.12.002
Abstract: Current HLA-typing methods are typically designed to provide exquisitely-detailed identification of multiple HLA-alleles to satisfy the requirements for organ and bone marrow transplantation or genetic studies. Many human immunological studies, on the other hand, focus around only a small number of HLA alleles that are abundant or of relevance to specific diseases. Consequently, for such studies, many HLA typing approaches are not cost-effective and are potentially complicated, slow and not easily performed in-house. Work-flow would be streamlined by a simple, inexpensive and rapid typing method able to be performed in-house. We outline a straightforward approach that provides appropriate data for much immunological research. In a predominantly Caucasian population, flow cytometry using anti-HLA-A2, -B8 and -B7 antibodies consistently and accurately screened for s les carrying the highly-abundant HLA class I alleles HLA-A*02:01, -B*08:01 and -B*07:02 that form the focus of immunological studies. Next, we describe a straightforward and simple strategy for design and use of allele-specific PCR primers to identify, at high-resolution, alleles of interest. When combined with a simple gDNA extraction technique this provides reliable, simple and inexpensive in-house HLA typing demonstrated here for highly-abundant HLA class I alleles.
Publisher: Elsevier BV
Date: 07-2021
Publisher: Oxford University Press (OUP)
Date: 02-02-2021
DOI: 10.1093/RHEUMATOLOGY/KEAB093
Abstract: Peripheral ulcerative keratitis (PUK) is a severe corneal condition associated with uncontrolled RA. Tocilizumab (TCZ) is used to control RA, however, episodes of paradoxical ocular inflammation have been reported in TCZ-treated patients. We report a case series of PUK in TCZ-treated RA patients with ophthalmological and systemic findings and discuss the potential underlying mechanisms. Four patients (six eyes), 47–62 years of age, were included. At the onset of PUK, the median duration of RA was 13 years [interquartile range (IQR) 3–13] and the median treatment with TCZ was 9 months (IQR 3–14). Two patients had active disease [28-joint DAS (DAS28) & .2] and the disease was controlled in two patients (DAS28 ≤3.2). TCZ was initially replaced by another immunomodulatory treatment in all patients and later reintroduced in two patients without PUK recurrence. Corneal inflammation was controlled in all cases with local and systemic treatments, with severe visual loss in one eye. PUK may occur in patients with long-standing RA after a switch to TCZ and can be interpreted, depending on the context, as insufficient efficacy or a paradoxical manifestation. These cases highlight the urgent need for reliable biomarkers of the efficacy and paradoxical reactions of biologics.
Publisher: Elsevier BV
Date: 10-2022
DOI: 10.1016/J.JBSPIN.2022.105426
Abstract: To assess associations between ophthalmological features and the main systemic biomarkers of primary Sjögren's Syndrome (pSS), and to identify systemic biomarkers associated with severe keratoconjunctivitis sicca (KCS) in pSS patients. In this cross-sectional study, data was retrospectively extracted from the monocentric cohort of the French reference centre for pSS. We analysed data from the initial visit of patients admitted for suspicion of pSS and included patients validating pSS ACR/EULAR classification criteria. Ophthalmological assessment included Schirmer's test, tear break-up time, ocular staining score (OSS), and visual analogue scale (DED-VAS) for dry eye disease (DED) symptoms. Results of minor salivary gland biopsy, unstimulated whole salivary flow rate, anti-SSA/Ro antibodies, anti-SSB/La antibodies, and rheumatoid factor (RF) were collected. A total of 253 patients (245 females) with confirmed pSS, aged 56.6±13.0 years, were included, among which 37% had severe KCS. Multivariate analysis showed that the presence of anti-SSA/Ro antibodies, anti-SSB/La antibodies and RF were associated with conjunctival OSS (odds ratio-OR-=1.25 per OSS unit increase confidence interval-CI-95%=1.05-1.49 P=0.01 OR=1.31 per OSS unit increase CI95%=1.09-1.58, P=0.002, and OR=1.34 per OSS unit increase CI95%=1.12-1.59 P=0.001, respectively). Both anti-SSB/La antibodies and DED-VAS ≥ 5 were significantly associated with severe KCS (OR=2.03 CI95%=1.03-4.00 P .05 and OR=2.52, CI95%=1.31-4.90 P .01, respectively). Association between conjunctival OSS and systemic biomarkers of pSS indicate the crucial importance of conjunctival staining when pSS is suspected as a cause of DED. Conversely, patients with anti-SSB and DED-VAS ≥ 5 features should be prioritized for extensive evaluation by an ophthalmologist due to their association with severe KCS.
Publisher: Elsevier BV
Date: 09-2014
DOI: 10.1038/JID.2014.174
Publisher: BMJ
Date: 07-2020
Abstract: Dendritic cells (DCs) are crucial for the efficacy of cancer vaccines, but current vaccines do not harness the key cDC1 subtype required for effective CD8 + T-cell-mediated tumor immune responses. Vaccine immunogenicity could be enhanced by specific delivery of immunogenic tumor antigens to CD141 + DCs, the human cDC1 equivalent. CD141 + DCs exclusively express the C-type-lectin-like receptor CLEC9A, which is important for the regulation of CD8 + T cell responses. This study developed a new vaccine that harnesses a human anti-CLEC9A antibody to specifically deliver the immunogenic tumor antigen, NY-ESO-1 (New York esophageal squamous cell carcinoma 1), to human CD141 + DCs. The ability of the CLEC9A-NY-ESO-1 antibody to activate NY-ESO-1-specific naïve and memory CD8 + T cells was examined and compared with a vaccine comprised of a human DEC-205-NY-ESO-1 antibody that targets all human DCs. Human anti-CLEC9A, anti-DEC-205 and isotype control IgG4 antibodies were genetically fused to NY-ESO-1 polypeptide. Cross-presentation to NY-ESO-1-epitope-specific CD8 + T cells and reactivity of T cell responses in patients with melanoma were assessed by interferon γ (IFNγ) production following incubation of CD141 + DCs and patient peripheral blood mononuclear cells with targeting antibodies. Humanized mice containing human DC subsets and a repertoire of naïve NY-ESO-1-specific CD8 + T cells were used to investigate naïve T cell priming. T cell effector function was measured by expression of IFNγ, MIP-1β, tumor necrosis factor and CD107a and by lysis of target tumor cells. CLEC9A-NY-ESO-1 antibodies (Abs) were effective at mediating delivery and cross-presentation of multiple NY-ESO-1 epitopes by CD141 + DCs for activation of NY-ESO-1-specific CD8 + T cells. When benchmarked to NY-ESO-1 conjugated to an untargeted control antibody or to anti-human DEC-205, CLEC9A-NY-ESO-1 was superior at ex vivo reactivation of NY-ESO-1-specific T cell responses in patients with melanoma. Moreover, CLEC9A-NY-ESO-1 induced priming of naïve NY-ESO-1-specific CD8 + T cells with polyclonal effector function and potent tumor killing capacity in vitro. These data advocate human CLEC9A-NY-ESO-1 Ab as an attractive strategy for specific targeting of CD141 + DCs to enhance tumor immunogenicity in NY-ESO-1-expressing malignancies.
Publisher: American Society for Microbiology
Date: 12-2019
DOI: 10.1128/JVI.01586-19
Abstract: Herpetic keratitis (HK) is the leading cause of blindness by an infectious agent in the developed world. This disease can occur after reactivation of herpes simplex virus 1 in the trigeminal ganglia, leading to dissemination of virus to, and infection of, the cornea. A clinical paradox is evidenced by the bilateral presence of latent viral genomes in both trigeminal ganglia, while for any given patient the disease is unilateral with recurrences in a single eye. Our study links the kinetics of early infection to unilateral disease phenomenon and demonstrates protection against viral reactivation when kinetics are exploited. Our results have direct implications in the understanding of human disease pathogenesis and immunotherapeutic strategies for the treatment of HK and viral reactivations.
Publisher: MDPI AG
Date: 05-02-2021
DOI: 10.3390/IJMS22041625
Abstract: The distinct properties of allo-reactive T-cell repertoires are not well understood. To investigate whether auto-reactive and allo-reactive T-cell repertoires encoded distinct properties, we used dextramer enumeration, enrichment, single-cell T-cell receptor (TCR) sequencing and multiparameter analysis. We found auto-reactive and allo-reactive T-cells differed in mean ex vivo frequency which was antigen dependent. Allo-reactive T-cells showed clear differences in TCR architecture, with enriched usage of specific T-cell receptor variable (TRBJ) genes and broader use of T-cell receptor variable joining (TRBJ) genes. Auto-reactive T-cell repertoires exhibited complementary determining regions three (CDR3) lengths using a Gaussian distribution whereas allo-reactive T-cell repertoires exhibited distorted patterns in CDR3 length. CDR3 loops from allo-reactive T-cells showed distinct physical-chemical properties, tending to encode loops that were more acidic in charge. Allo-reactive T-cell repertoires differed in ersity metrics, tending to show increased overall ersity and increased homogeneity between repertoires. Motif analysis of CDR3 loops showed allo-reactive T-cell repertoires differed in motif preference which included broader motif use. Collectively, these data conclude that allo-reactive T-cell repertoires are indeed different to auto-reactive repertoires and provide tangible metrics for further investigations and validation. Given that the antigens studied here are overexpressed on multiple cancers and that allo-reactive TCRs often show increased ligand affinity, this new TCR bank also has translational potential for adoptive cell therapy, soluble TCR-based therapy and rational TCR design.
Publisher: Elsevier BV
Date: 11-2014
DOI: 10.1016/J.JCONREL.2014.08.021
Abstract: The barrier morphology of skin provides major obstacles for the application of siRNA for gene silencing, which current delivery technologies do not effectively overcome. Emerging technologies utilise microprojection array devices to penetrate into the skin epidermis and dermis for delivery of drug payloads. Delivery of siRNA by such devices has been proven in principle, yet requires optimisation for clinical applications. Herein, we demonstrate the use of Nanopatch™ microprojection arrays to deliver liposome-encapsulated siRNA to overcome skin barrier, and in vivo siRNA delivery hurdles. This application provided effective silencing of CXCL1 expression induced by the co-delivery of Fluvax 2012® by microprojection array. Liposomes encapsulating siRNA were dry-coated onto microprojection arrays, and remained intact after elution from arrays in vitro. Microprojection arrays facilitated the delivery of fluorescently-labelled nucleic acids through murine ear stratum corneum to the epidermis and dermis, with diffusion from microprojections into adjacent skin evident within 30s. CXCL1 mRNA, induced by delivery of Fluvax by microprojection array, was reduced by 75% up to 20 h post-treatment by co-delivery of liposome-encapsulated CXCL1-specific siRNA, but not by arrays co-delivering liposome-encapsulated control siRNA. CXCL1 protein expression in explant cultures from skin treated with arrays bearing CXCL1 specific or control siRNA was similarly reduced. These results as a test case have many implications for gene silencing in skin and inflammation, with the benefit of targeted delivery using microprojection arrays to deliver liposome-encapsulated siRNA.
Publisher: Elsevier BV
Date: 03-2010
DOI: 10.1016/J.VIROL.2009.11.042
Abstract: We have previously demonstrated that the potent immunogenicity of hepatitis B surface antigen (HBsAg) may be exploited to deliver foreign antigens for cytotoxic T-lymphocyte (CTL) induction. Here we demonstrate that a single low-dose immunization with rHBsAg DNA is sufficient to prime for CTL responses against encoded foreign epitope and that the responses may be recalled many months after immunization. We show that simultaneous disease-protective CTL responses restricted through a ersity of MHC class I haplotypes are elicited by recombinant (r) HBsAg DNA containing multiple viral epitopes appended as a C'-terminal polyepitope or encoded in idually within the HBsAg polypeptide. CTL responses delivered by rHBsAg DNA were elicited in the presence of HBsAg-directed antibody. These studies vindicate the use of HBsAg as a powerful vector to deliver CTL responses to foreign antigen and have implications for a multidisease vaccine applicable to an MHC-polymorphic population.
Publisher: Springer Science and Business Media LLC
Date: 30-01-2021
DOI: 10.1186/S13023-021-01707-6
Abstract: Thygeson’s superficial punctate keratitis (TSPK) is a rare and still poorly understood disease of the ocular surface, responsible for recurrent episodes of photophobia and eye pain. While TSPK is considered as a benign condition, a subset of patients has frequent recurrences or even chronic disease, two situations in which there are currently no therapeutic guidelines. We used a preexisting Facebook TSPK patient support group to assess the clinical journey and the burden of disease of TSPK. An online survey was sent to the patient support group. The first part of the questionnaire gathered information on demographics and the patient’s clinical journey [diagnostic modalities, symptoms, duration and frequency of recurrent episodes (RE), efficacy and tolerance to treatments]. The second part focused on quality of life (QoL) using the Ocular Surface Disease-QoL (OSD-QoL) questionnaire. Seventy-two patients out of 595 members of the support group completed the questionnaire during the 3-months study period. Eighty percent of patients developed symptoms before 30 years old, and 47% reported a delay in the diagnosis above 1 year. Sixty percent of patients reported over 5 RE yearly, and 18% of RE lasted more than 3 months. Forty percent of all patients used cyclosporine eyedrops (50% of those with 5 episodes/year) and it was perceived as effective by 72% of these patients. The impact on daily life activities was judged as severe by 22% of patients, while 38% reported reduced professional activity and 80% were deeply saddened by their eye condition. TSPK patients may present with frequent recurrences and/or chronic disease, that result in a severe impact on QoL, and an off-label use of topical immunomodulatory eye drops, suggesting the urgent need for controlled studies. The utility of using social networks for rare ophthalmic disease research includes, faster data collection, data from patients across the globe, and also raises relevant questions about their real needs.
Publisher: Springer Science and Business Media LLC
Date: 12-03-2018
Publisher: Elsevier BV
Date: 06-2022
DOI: 10.1016/J.AJO.2022.01.010
Abstract: To describe the clinical and virological profiles of patients with herpes simplex keratitis (HSK) caused by acyclovir-resistant (ACV Multicenter retrospective case series. HSV-1 resistance to ACV was confirmed using sequencing of genes encoding HSV-1 thymidine kinase (TK) and DNA polymerase (DNA pol). Data were collected on the number of HSK episodes before and after the diagnosis of resistance, ocular findings including the type of HSK, immune status of patients, antiviral treatments, and HSV-1 genotypic resistance profiles. This study evaluated 18 HSK patients (13 male and 5 female, aged 66.8 ± 4.7 years) with ACV HSV-1 resistance to ACV must be suspected in HSK patients with recurrences despite AVP and/or in cases that respond poorly to a suppressive antiviral regimen. Immunocompromised patients and/or those with longstanding disease may be particularly at risk for developing resistance.
Publisher: Elsevier BV
Date: 04-2023
Publisher: Wiley
Date: 10-02-2018
DOI: 10.1111/IMCB.12009
Abstract: Mice reconstituted with human hematopoietic stem cells are valuable models to study aspects of the human immune system in vivo. We describe a humanized mouse model (hu mice) in which fully functional human CD141
Publisher: Elsevier BV
Date: 02-2023
Publisher: Research Square Platform LLC
Date: 04-12-2020
DOI: 10.21203/RS.3.RS-118219/V1
Abstract: Aims / background: Rubella virus-associated uveitis (RVAU) classically presents with the clinical features of Fuchs uveitis syndrome (FUS). We report a series RVAU, and discuss the relevance of available diagnostic strategies, and vaccination to prevent disease. Methods: We retrospectively included patients with RV-positive aqueous humor (AH) with RT-PCR and/or intraocular RV-IgG production, between January 2014 and December 2019. RV-IgG titers from AH and serum were compared with other virus-specific IgG titers (VZV and/or CMV and/or HSV-1), to determine the derived Goldmann-Witmer coefficient (GWC’). Clinical findings at presentation and during follow-up are reported, as well as the anti-RV vaccination status. Results: All 13 included patients demonstrated intraocular synthesis of RV-IgG (median GWC’: 9.5 3.2-100). RV-RNA was detected in one patient while PCR results were negative for other HSV1, VZV and CMV. The mean delay in diagnosis was 13 ± 12.6 years, with an initial presentation of FUS in only 3 patients (23 %). Only four patients had been vaccinated, but all after the recommended age. Conclusion: As RVAU is a pleiomorphic entity, virological analysis (RV RT-PCR and GWC’) of aqueous humor is essential to improve the diagnosis and management of this entity. Improper vaccination against RV appears to be implicated in RVAU.
Publisher: SAGE Publications
Date: 14-03-2022
DOI: 10.1177/11206721221087562
Abstract: Rubella virus-associated uveitis (RVAU) classically presents with the clinical features of Fuchs uveitis syndrome (FUS). We report a series RVAU, and discuss the relevance of available diagnostic strategies, and how vaccination could potentially prevent disease. We retrospectively included patients with RV-positive aqueous humor (AH) with RT-PCR and/or intraocular RV-IgG production, between January 2014 and December 2019. RV-IgG titers from AH and serum were compared with other virus-specific IgG titers (VZV and/or CMV and/or HSV-1), to determine the derived Goldmann-Witmer coefficient (GWC’). Clinical findings at presentation and during follow-up are reported, as well as the anti-RV vaccination status. All 13 included patients demonstrated intraocular synthesis of RV-IgG (median GWC’: 9.5 3.2–100). RV-RNA was detected in one patient while PCR results were negative for other HSV1, VZV and CMV. The mean delay in diagnosis was 13 ± 12.6 years, with an initial presentation of FUS in only 3 patients (23%). Only four patients had been vaccinated, but all after the recommended age. As RVAU is a pleiomorphic entity, virological analysis (RV RT-PCR and GWC’) of aqueous humor is essential to improve the diagnosis and management of this entity. Improper vaccination against RV appears to be implicated in RVAU.
Publisher: Elsevier BV
Date: 06-2019
DOI: 10.1016/J.AJO.2019.02.012
Abstract: Immune checkpoint inhibitors (ICI) targeting the programmed cell death protein 1 (PD-1), or its ligand PD-L1, are the mainstay of metastatic cancer treatment. Patients receiving these treatments may develop immune-related adverse events (irAEs). This study aimed to estimate the prevalence and describe the clinical patterns of moderate-to-severe ocular irAEs-associated with anti-PD-(L)1 treatment. Prospective case series. This study included patients recruited via (1) a single-center prospective cohort and (2) a national pharmacovigilance registry between June 2014 and March 2018, and focused on patients with moderate-to-severe ocular irAEs following anti-PD-(L)1. All patients underwent a comprehensive ophthalmologic assessment. The main outcome measure was the prevalence of moderate-to-severe ocular irAEs. Of a total of 745 patients included in the prospective cohort, 3 developed moderate-to-severe ocular irAEs, providing a prevalence of 0.4% and an incidence of 0.7 per 1000 patient-months of treatment. An additional 5 cases of moderate-to-severe ocular irAEs were reported through the national registry. From these 8 patients, 5 presented with intraocular inflammation, 2 with ocular surface disease, and 1 with orbital myopathy. Five patients (62.5%) experienced additional extraophthalmologic irAEs. Ocular irAEs led to permanent discontinuation of anti-PD-(L)1 in 4 patients. Treatment by local and/or systemic corticosteroids allowed resolution or control of the ocular symptoms in 7 of 8 patients. Although uncommon, anti-PD-(L)1-associated ocular complications may be sight-threatening and lead to discontinuation of anti-PD-(L)1 treatments. Patients complaining of eye problems while receiving ICI treatment should immediately be seen by an ophthalmologist.
Publisher: Wiley
Date: 2022
DOI: 10.1002/CTI2.1361
Abstract: DROSHA and DICER have central roles in the biogenesis of microRNAs (miRNAs). However, we previously showed that in the murine system, DROSHA has an alternate function where it directly recognises and cleaves protein‐coding messenger (m)RNAs and this is critical for safeguarding the pluripotency of haematopoietic stem cells (HSCs). Maintenance of murine HSC function is dependent on DROSHA‐mediated cleavage of two mRNAs, Myl9 and Todr1 . The goal of this study is to determine whether this pathway is conserved in human HSCs. DROSHA and DICER were knocked down in human cord blood CD34 + HSCs with short hairpin RNAs. The function of HSCs was analysed in vitro and in humanised mice. Analysis of mRNA cleavage was performed by capture of 5′ phosphorylated RNAs. Consistent with murine HSCs, DROSHA knockdown impaired the differentiation of human HSCs in vitro and engraftment into humanised mice, whereas DICER knockdown had no impact. DROSHA cleaves the MYL9 mRNA in human HSCs and DROSHA deficiency resulted in the accumulation of the mRNA. However, ectopic expression of MYL9 did not impair human HSC function. We were unable to identify a human homolog of Todr1. A miRNA‐independent function of DROSHA is critical for the function of human HSCs. DROSHA directly recognises and degrades mRNAs in humans HSCs. However, unlike in murine HSCs, the degradation of the MYL9 mRNA alone is not critical for human HSC function. Therefore, DROSHA must be inhibiting other targets and/or has another miRNA‐independent function that is essential for safeguarding the pluripotency of human HSCs.
Publisher: Wiley
Date: 2020
DOI: 10.1002/CTI2.1141
Publisher: Elsevier BV
Date: 03-2023
Publisher: American Diabetes Association
Date: 31-12-2014
DOI: 10.2337/DB14-1151
Abstract: Dysfunction in effector memory has been proposed to contribute to autoimmunity in type 1 diabetes (T1D). Using a unique cohort of age- and sex-matched T1D patients, nonaffected siblings, and unrelated control children, we undertook a detailed analysis of proliferation, activation, effector responses, and apoptosis in reactivated CD4+Tm cells during T-cell receptor stimulation. Across cohorts, there was no difference in the proliferation of reactivated CD4+Tm cells. In T1D patients and siblings, CD4+Tm cells easily acquired the activated CD25+ phenotype and effectively transitioned from a central (CD62L+Tcm) to an effector memory (CD62L−Tem) phenotype with an elevated cytokine “signature” comprising interferon (IFN)-γ and interleukin-10 in T1D patients and IFN-γ in siblings. This lified Tem phenotype also exhibited an exaggerated immune shutdown with heightened sensitivity to activation-induced cell death and Fas-independent apoptosis. Apoptosis resulted in the elimination of one-half of the effector memory in T1D patients and siblings compared with one-third of the effector memory in control subjects. These data suggest genetic/environment-driven immune alteration in T1D patients and siblings that manifests in an exaggerated CD4+Tem response and shutdown by apoptosis. Further immunological studies are required to understand how this exaggerated CD4+Tem response fits within the pathomechanisms of T1D and how the effector memory can be modulated for disease treatment and/or prevention.
Publisher: Elsevier BV
Date: 09-2016
DOI: 10.1016/J.JCONREL.2016.06.045
Abstract: DNA vaccines have many advantages such as thermostability and the ease and rapidity of manufacture for ex le, in an influenza pandemic situation where rapid production of vaccine is essential. However, immunogenicity of DNA vaccines was shown to be poor in humans unless large doses of DNA are used. If a highly efficacious DNA vaccine delivery system could be identified, then DNA vaccines have the potential to displace protein vaccines. In this study, we show in a C57BL/6 mouse model, that the Nanopatch, a microprojection array of high density (>21,000 projections/cm(2)), could be used to deliver influenza nucleoprotein DNA vaccine to skin, to generate enhanced antigen specific antibody and CD8(+) T cell responses compared to the conventional intramuscular (IM) delivery by the needle and syringe. Antigen specific antibody was measured using ELISA assays of mice vaccinated with a DNA plasmid containing the nucleoprotein gene of influenza type A/WSN/33 (H1N1). Antigen specific CD8(+) T cell responses were measured ex-vivo in splenocytes of mice using IFN-γ ELISPOT assays. These results and our previous antibody and CD4(+) T cell results using the Nanopatch delivered HSV DNA vaccine indicate that the Nanopatch is an effective delivery system of general utility that could potentially be used in humans to increase the potency of the DNA vaccines.
Publisher: Elsevier BV
Date: 11-2018
DOI: 10.1016/J.VIROL.2007.06.041
Abstract: We propose the replacement of endogenous epitopes with foreign epitopes to exploit the highly immunogenic hepatitis B surface antigen (HBsAg) as a vaccine vector to elicit disease-protective cytotoxic T-lymphocyte (CTL) responses. Locations were defined within the HBsAg gene where replacements of DNA encoding HBsAg epitopes may be made to generate functional recombinant (r) HBsAg DNA vaccines. We demonstrate that rHBsAg DNA vaccines encoding multiple copies of a model tumor epitope from human papillomavirus (HPV) elicit enhanced CTL responses compared to rHBsAg DNA vaccines encoding a single copy. We show that rHBsAg DNA vaccines elicit a marked prophylactic and long-lived therapeutic protection against epitope expressing tumor, although protective efficacy was not improved by increasing the number of copies of the tumor epitope DNA. These results demonstrate the efficacy of HBsAg as a vector for the delivery of foreign CTL epitopes using the epitope replacement strategy, and have implications for rHBsAg vaccine design. The results also have implications for the derivation of a therapeutic vaccine for HPV-associated squamous carcinoma.
Location: Australia
Location: Australia
Location: France
No related grants have been discovered for Oscar Haigh.