Molecular neurodegeneration
Bhargavan, B;Woollard, SM;McMillan, JE;Kanmogne, GD;
PMID: 34809709 | DOI: 10.1186/s13024-021-00500-0
Neurocognitive impairment is present in 50% of HIV-infected individuals and is often associated with Alzheimer's Disease (AD)-like brain pathologies, including increased amyloid-beta (Aβ) and Tau hyperphosphorylation. Here, we aimed to determine whether HIV-1 infection causes AD-like pathologies in an HIV/AIDS humanized mouse model, and whether the CCR5 antagonist maraviroc alters HIV-induced pathologies.NOD/scid-IL-2Rγcnull mice engrafted with human blood leukocytes were infected with HIV-1, left untreated or treated with maraviroc (120 mg/kg twice/day). Human cells in animal's blood were quantified weekly by flow cytometry. Animals were sacrificed at week-3 post-infection; blood and tissues viral loads were quantified using p24 antigen ELISA, RNAscope, and qPCR. Human (HLA-DR+) cells, Aβ-42, phospho-Tau, neuronal markers (MAP 2, NeuN, neurofilament-L), gamma-secretase activating protein (GSAP), and blood-brain barrier (BBB) tight junction (TJ) proteins expression and transcription were quantified in brain tissues by immunohistochemistry, immunofluorescence, immunoblotting, and qPCR. Plasma Aβ-42, Aβ-42 cellular uptake, release and transendothelial transport were quantified by ELISA.HIV-1 significantly decreased human (h)CD4+ T-cells and hCD4/hCD8 ratios; decreased the expression of BBB TJ proteins claudin-5, ZO-1, ZO-2; and increased HLA-DR+ cells in brain tissues. Significantly, HIV-infected animals showed increased plasma and brain Aβ-42 and phospho-Tau (threonine181, threonine231, serine396, serine199), associated with transcriptional upregulation of GSAP, an enzyme that catalyzes Aβ formation, and loss of MAP 2, NeuN, and neurofilament-L. Maraviroc treatment significantly reduced blood and brain viral loads, prevented HIV-induced loss of neuronal markers and TJ proteins; decreased HLA-DR+ cells infiltration in brain tissues, significantly reduced HIV-induced increase in Aβ-42, GSAP, and phospho-Tau. Maraviroc also reduced Aβ retention and increased Aβ release in human macrophages; decreased the receptor for advanced glycation end products (RAGE) and increased low-density lipoprotein receptor-related protein-1 (LRP1) expression in human brain endothelial cells. Maraviroc induced Aβ transendothelial transport, which was blocked by LRP1 antagonist but not RAGE antagonist.Maraviroc significantly reduced HIV-induced amyloidogenesis, GSAP, phospho-Tau, neurodegeneration, BBB alterations, and leukocytes infiltration into the CNS. Maraviroc increased cellular Aβ efflux and transendothelial Aβ transport via LRP1 pathways. Thus, therapeutically targeting CCR5 could reduce viremia, preserve the BBB and neurons, increased brain Aβ efflux, and reduce AD-like neuropathologies.
Molecular therapy : the journal of the American Society of Gene Therapy
Handyside, B;Ismail, AM;Zhang, L;Yates, B;Xie, L;Sihn, CR;Murphy, R;Bouwman, T;Kim, CK;De Angelis, R;Karim, OA;McIntosh, NL;Doss, MX;Shroff, S;Pungor, E;Bhat, VS;Bullens, S;Bunting, S;Fong, S;
PMID: 36348622 | DOI: 10.1016/j.ymthe.2022.11.001
Recombinant adeno-associated virus (rAAV) vectors are often produced in HEK293 or Spodoptera frugiperda (Sf)-based cell lines. We compared expression profiles of "oversized" (∼5,000 bp) and "standard-sized" (4,600 bp) rAAV5-human α1-antitrypsin (rAAV5-hA1AT) vectors manufactured in HEK293 or Sf cells and investigated molecular mechanisms mediating expression decline. C57BL/6 mice received 6 × 1013 vg/kg of vector, and blood and liver samples were collected through week 57. For all vectors, peak expression (weeks 12-24) declined by 50% to week 57. For Sf- and HEK293-produced oversized vectors, serum hA1AT was initially comparable, but in weeks 12-57, Sf vectors provided significantly higher expression. For HEK293 oversized vectors, liver genomes decreased continuously through week 57 and significantly correlated with A1AT protein. In RNA-sequencing analysis, HEK293 vector-treated mice had significantly higher inflammatory responses in liver at 12 weeks compared with Sf vector- and vehicle-treated mice. Thus, HEK293 vector genome loss led to decreased transgene protein. For Sf-produced vectors, genomes did not decrease from peak expression. Instead, vector genome accessibility significantly decreased from peak to week 57 and correlated with transgene RNA. Vector DNA interactions with active histone marks (H3K27ac/H3K4me3) were significantly reduced from peak to week 57, suggesting that epigenetic regulation impacts transgene expression of Sf-produced vectors.
Guo D, Zhao X, Wang A, Xie Q, Xu X, Sun J.
PMID: 30594747 | DOI: 10.1016/j.humpath.2018.10.041
The immunosuppressive effect of the programmed death (PD)-1/PD-L1 pathway plays an important role in the treatment of a variety of tumors, such as lung and breast cancer, but there is little literature about PD-1/PD-L1 in pheochromocytomas/paragangliomas (PCC/PGLs). We explored the relationship of PD-L1 and malignant behavior in 77 cases of PCC/PGL using immunohistochemistry (IHC) to assess protein expression and RNAscope to detect mRNA expression in 20 cases. The IHC data showed that 59.74% of the PCC/PGLs expressed PD-L1, and the extent of expression was highly correlated with Ki-67 (P = .019) and hypertension (P = .013), but not with age, sex, tumor size, capsular invasion, tumor necrosis, relapse/distant metastasis, secretion of noradrenaline/adrenaline/dopamine, or diabetes mellitus. In addition, we found an excellent correlation of PD-L1 mRNA and protein expression with a κ coefficient of 0.828, and further stratification of the IHC and RNAscope findings showed high consistency (Pearson's coefficient 0.753). The correlation of PD-L1 and Ki-67 indicated that PD-L1 could be considered a malignant proliferation biomarker for PCC/PGLs, which would be a putative biomarker for anti-PD-L1 therapies.
Shang Z, Yu J, Sun L, Tian J, Zhu S, Zhang B, Dong Q, Jiang N, Flores-Morales A, Chang C, Niu Y.
PMID: 30773595 | DOI: 10.1093/nar/gkz108
In PTEN-deficient prostate cancers, AKT signaling may be activated upon suppression of androgen receptor signaling. Activation of AKT as well as NF-κB signaling involves a key regulatory protein complex containing PHLPP, FKBP51 and IKKα. Here, we report a critical role of lncRNA PCAT1 in regulating the PHLPP/FKBP51/IKKα complex and progression of castration-resistant prostate cancer (CRPC). Using database queries, bioinformatic analyses, as well as RIP and RNA pull-down assays, we discovered and validated that the lncRNA-PCAT1 perturbs the PHLPP/FKBP51/IKKα complex and activates AKT and NF-κB signaling. Expression of lncRNA-PCAT1 is positively linked to CRPC progression. PCAT1 binds directly to FKBP51, displacing PHLPP from the PHLPP/FKBP51/IKKα complex, leading to activation of AKT and NF-κB signaling. Targeting PCAT1 restores PHLPP binding to FKBP1 leading to suppression of AKT signaling. Preclinical study in a mouse model of CRPC suggests therapeutic potential by targeting lncRNA PCAT1 to suppress CRPC progression. Together, the newly identified PCAT1/FKBP51/IKKα complex provides mechanistic insight in the interplay between AKT, NF-κB and AR signaling in CRPC, and the preclinical studies suggest that a novel role for PCAT1 as a therapeutic target.
Journal of visualized experiments : JoVE
Carver, AJ;Taylor, RJ;Stevens, HE;
PMID: 37125793 | DOI: 10.3791/64760
The placenta is an essential organ that regulates and maintains mammalian development in utero. The placenta is responsible for the transfer of nutrients and waste between the mother and fetus and the production and delivery of growth factors and hormones. Placental genetic manipulations in mice are critical for understanding the placenta's specific role in prenatal development. Placental-specific Cre-expressing transgenic mice have varying effectiveness, and other methods for placental gene manipulation can be useful alternatives. This paper describes a technique to directly alter placental gene expression using CRISPR gene manipulation, which can be used to modify the expression of targeted genes. Using a relatively advanced surgical approach, pregnant dams undergo a laparotomy on embryonic day 12.5 (E12.5), and a CRISPR plasmid is delivered by a glass micropipette into the individual placentas. The plasmid is immediately electroporated after each injection. After dam recovery, the placentas and embryos can continue development until assessment at a later time point. The evaluation of the placenta and offspring after the use of this technique can determine the role of time-specific placental function in development. This type of manipulation will allow for a better understanding of how placental genetics and function impact fetal growth and development in multiple disease contexts.
medRxiv : the preprint server for health sciences
Gonzalez, V;Li, L;Buarpung, S;Prahl, M;Robinson, JF;Gaw, SL;
PMID: 36778281 | DOI: 10.1101/2023.02.01.23285349
Despite universal recommendations for COVID-19 mRNA vaccination in pregnancy, uptake has been lower than desired. There have been limited studies of the direct impact of COVID-19 mRNA vaccine exposure in human placental tissue. Using a primary human villous explant model, we investigated the uptake of two common mRNA vaccines (BNT162b2 Pfizer-BioNTech or mRNA-1273 Moderna), and whether exposure altered villous cytokine responses. Explants derived from second or third trimester chorionic villi were incubated with vaccines at supraphysiologic concentrations and analyzed at two time points. We observed minimal uptake of mRNA vaccines in placental explants by in situ hybridization and quantitative RT-PCR. No specific or global cytokine response was elicited by either of the mRNA vaccines in multiplexed immunoassays. Our results suggest that the human placenta does not readily absorb the COVID-19 mRNA vaccines nor generate a significant inflammatory response after exposure.
Potluri, T;Taylor, MJ;Stulberg, JJ;Lieber, RL;Zhao, H;Bulun, SE;
PMID: 35439171 | DOI: 10.1172/jci.insight.152011
Greater than 25% of all men develop an inguinal hernia in their lifetime, and more than 20 million inguinal hernia repair surgeries are performed worldwide each year. The mechanisms causing abdominal muscle weakness, the formation of inguinal hernias, or their recurrence are largely unknown. We previously reported that excessively produced estrogen in the lower abdominal muscles (LAMs) triggers extensive LAM fibrosis, leading to hernia formation in a transgenic male mouse model expressing the human aromatase gene (Aromhum). To understand the cellular basis of estrogen-driven muscle fibrosis, we performed single-cell RNA sequencing on LAM tissue from Aromhum and wild-type littermates. We found a fibroblast-like cell group composed of 6 clusters, 2 of which were validated for their enrichment in Aromhum LAM tissue. One of the potentially novel hernia-associated fibroblast clusters in Aromhum was enriched for the estrogen receptor-α gene (Esr1hi). Esr1hi fibroblasts maximally expressed estrogen target genes and seemed to serve as the progenitors of another cluster expressing ECM-altering enzymes (Mmp3hi) and to upregulate expression of proinflammatory, profibrotic genes. The discovery of these 2 potentially novel and unique hernia-associated fibroblasts may lead to the development of novel treatments that can nonsurgically prevent or reverse inguinal hernias.
Molecular Therapy - Methods & Clinical Development
Sihn, C;Handyside, B;Liu, S;Zhang, L;Murphy, R;Yates, B;Xie, L;Torres, R;Russell, C;O’Neill, C;Pungor, E;Bunting, S;Fong, S;
| DOI: 10.1016/j.omtm.2021.12.004
Valoctocogene roxaparvovec (AAV5-hFVIII-SQ) is an adeno-associated virus serotype 5 (AAV5)-based gene therapy vector containing a B-domain-deleted human coagulation Factor VIII (hFVIII) gene controlled by a liver-selective promoter. AAV5-hFVIII-SQ is currently under clinical investigation as treatment for severe hemophilia A. The full-length AAV5-hFVIII-SQ is >4.9 kb, which is over the optimal packaging limit of AAV5. Following administration, the vector must undergo a number of genome-processing, assembly, and repair steps to form full-length circularized episomes that mediate long-term FVIII expression in target tissue. To understand the processing kinetics of the oversized AAV5-hFVIII-SQ vector genome into circular episomes, we characterized the various molecular forms of the AAV5-hFVIII-SQ genome at multiple time points up to 6 months postdose in the liver of murine and nonhuman primate models. Full-length circular episomes were detected in liver tissue beginning 1 week postdosing. Over 6 months, quantities of circular episomes (in predominantly head-to-tail configuration) increased, while DNA species lacking inverted terminal repeats were preferentially degraded. Levels of duplex, circular, full-length genomes significantly correlated with levels of hFVIII-SQ RNA transcripts in mice and nonhuman primates dosed with AAV5-hFVIII-SQ. Altogether, we show that formation of full-length circular episomes in the liver following AAV5-hFVIII-SQ transduction was associated with long-term FVIII expression.
High CYP27A1 expression is a biomarker of favorable prognosis in premenopausal patients with estrogen receptor positive primary breast cancer
Inasu, M;Bendahl, PO;Fernö, M;Malmström, P;Borgquist, S;Kimbung, S;
PMID: 34556659 | DOI: 10.1038/s41523-021-00333-6
27-hydroxycholesterol (27HC), synthesized from cholesterol by the enzyme CYP27A1, differentially impacts estrogen receptor positive (ER+) breast cancer (BC) cell growth depending on estrogen levels. This study examined the association between CYP27A1 expression and prognosis in a cohort of 193 premenopausal patients with lymph node-negative primary BC with limited exposure to adjuvant systemic cancer treatments. In multivariable analyses among patients with ER+ tumors, high CYP27A1 protein and mRNA expressions were associated with four- and eight-fold reductions in the incidence of distant recurrence-free survival events: HRadj = 0.26, 95% CI = 0.07-0.93 and HRadj = 0.13, 95% CI = 0.03-0.60, respectively. In vitro studies revealed that 27HC treatment potently inhibited ER+ BC cell proliferation under lipid-depleted conditions regardless of estradiol levels, transcriptionally mediated through the downregulation of ER signaling with a concomitant upregulation of cholesterol export. Importantly, if validated, these results may have implications for adjuvant treatment decisions in premenopausal patients, especially when de-escalation of therapy is being considered.
Dietary suppression of MHC class II expression in intestinal epithelial cells enhances intestinal tumorigenesis
Beyaz, S;Chung, C;Mou, H;Bauer-Rowe, KE;Xifaras, ME;Ergin, I;Dohnalova, L;Biton, M;Shekhar, K;Eskiocak, O;Papciak, K;Ozler, K;Almeqdadi, M;Yueh, B;Fein, M;Annamalai, D;Valle-Encinas, E;Erdemir, A;Dogum, K;Shah, V;Alici-Garipcan, A;Meyer, HV;Özata, DM;Elinav, E;Kucukural, A;Kumar, P;McAleer, JP;Fox, JG;Thaiss, CA;Regev, A;Roper, J;Orkin, SH;Yilmaz, ÖH;
PMID: 34529935 | DOI: 10.1016/j.stem.2021.08.007
Little is known about how interactions of diet, intestinal stem cells (ISCs), and immune cells affect early-stage intestinal tumorigenesis. We show that a high-fat diet (HFD) reduces the expression of the major histocompatibility complex class II (MHC class II) genes in intestinal epithelial cells, including ISCs. This decline in epithelial MHC class II expression in a HFD correlates with reduced intestinal microbiome diversity. Microbial community transfer experiments suggest that epithelial MHC class II expression is regulated by intestinal flora. Mechanistically, pattern recognition receptor (PRR) and interferon-gamma (IFNγ) signaling regulates epithelial MHC class II expression. MHC class II-negative (MHC-II-) ISCs exhibit greater tumor-initiating capacity than their MHC class II-positive (MHC-II+) counterparts upon loss of the tumor suppressor Apc coupled with a HFD, suggesting a role for epithelial MHC class II-mediated immune surveillance in suppressing tumorigenesis. ISC-specific genetic ablation of MHC class II increases tumor burden cell autonomously. Thus, HFD perturbs a microbiome-stem cell-immune cell interaction that contributes to tumor initiation in the intestine.
Activation of proneuronal transcription factor Ascl1 in maternal liver ensures a healthy pregnancy
Cellular and molecular gastroenterology and hepatology
Lee, J;Garcia, V;Nambiar, SM;Jiang, H;Dai, G;
PMID: 34438112 | DOI: 10.1016/j.jcmgh.2021.08.009
Maternal liver exhibits robust adaptations to pregnancy to accommodate the metabolic needs of developing and growing placenta and fetus by largely unknown mechanisms. We found that achaete-scute homolog-like 1 (Ascl1), a gene encoding a basic helix-loop-helix transcription factor essential for neuronal development, is highly activated in maternal hepatocytes during the second half of gestation in mice.To investigate whether and how Ascl1 plays a pregnancy-dependent role, we deleted the Ascl1 gene specifically in maternal hepatocytes from mid-gestation until term.As a result, we identified multiple Ascl1-dependent phenotypes. Maternal livers lacking Ascl1 exhibited aberrant hepatocyte structure, increased hepatocyte proliferation, enlarged hepatocyte size, reduced albumin production, and elevated release of liver enzymes, indicating maternal liver dysfunction. Simultaneously, maternal pancreas and spleen and the placenta displayed marked overgrowth; and the maternal ceca microbiome showed alterations in relative abundance of several bacterial subpopulations. Moreover, litters born from maternal hepatic Ascl1-deficient dams experienced abnormal postnatal growth after weaning, implying an adverse pregnancy outcome. Mechanistically, we found that maternal hepatocytes deficient for Ascl1 exhibited robust activation of insulin-like growth factor 2 expression, which may contribute to the Ascl1-dependent phenotypes widespread in maternal and uteroplacental compartments.In summary, we demonstrate that maternal liver, via activating Ascl1 expression, modulates the adaptations of maternal organs and the growth of the placenta to maintain a healthy pregnancy. Our studies reveal Ascl1 as a novel and critical regulator of the physiology of pregnancy.
Cholesterol-functionalized DNA/RNA heteroduplexes cross the blood-brain barrier and knock down genes in the rodent CNS
Nagata, T;Dwyer, CA;Yoshida-Tanaka, K;Ihara, K;Ohyagi, M;Kaburagi, H;Miyata, H;Ebihara, S;Yoshioka, K;Ishii, T;Miyata, K;Miyata, K;Powers, B;Igari, T;Yamamoto, S;Arimura, N;Hirabayashi, H;Uchihara, T;Hara, RI;Wada, T;Bennett, CF;Seth, PP;Rigo, F;Yokota, T;
PMID: 34385691 | DOI: 10.1038/s41587-021-00972-x
Achieving regulation of endogenous gene expression in the central nervous system (CNS) with antisense oligonucleotides (ASOs) administered systemically would facilitate the development of ASO-based therapies for neurological diseases. We demonstrate that DNA/RNA heteroduplex oligonucleotides (HDOs) conjugated to cholesterol or α-tocopherol at the 5' end of the RNA strand reach the CNS after subcutaneous or intravenous administration in mice and rats. The HDOs distribute throughout the brain, spinal cord and peripheral tissues and suppress the expression of four target genes by up to 90% in the CNS, whereas single-stranded ASOs conjugated to cholesterol have limited activity. Gene knockdown was observed in major CNS cell types and was greatest in neurons and microglial cells. Side effects, such as thrombocytopenia and focal brain necrosis, were limited by using subcutaneous delivery or by dividing intravenous injections. By crossing the blood-brain barrier more effectively, cholesterol-conjugated HDOs may overcome the limited efficacy of ASOs targeting the CNS without requiring intrathecal administration.