Journal club & Luncheon seminar


当ラボでは、HIVに関する研究の最新の情報を共有するために、2つの形式で論文紹介を行なっています。

1つは、月1回程度行うJournal club。ここでは最新のHIVに関する論文の要旨の紹介を行っています。

もう2つは、毎週1回行うLuncheon seminar。これは抄読会にあたるものです。三浦研と一緒に行なっており、HIVに関する論文を選び、その手法や注目すべき点について詳細に紹介し、我々の研究の参考にしています

 

各々が、重要だと感じた論文をここで紹介します。


Journal clubs


2018.4.20

 

 

明里

Journal :  SCIENCE TRANSLATIONAL MEDICINE 10, 6759, 2018

Title: CD32 is expressed on cells with transcriptionally active HIV but does not enrich for HIV DNA in resting T cells

URL: http://stm.sciencemag.org/content/10/437/eaar6759

Remarkable point:

HIV根治を目指す上で、リザーバー細胞の探索は重要な意味を持つ。昨年、DescoursらはCD32陽性休止期ヘルパーT細胞がHIVリザーバー細胞のマーカーであることを報告した(Nature, 2017)。しかし、本論文で著者らはCD32陽性ヘルパーT細胞の多くがCD69などの活性化マーカーを発現していること、CD32発現はHIVもしくはSIV感染ヘルパーT細胞と相関しないこと、むしろHIVを産生している活性化ヘルパーT細胞においてCD32が発現することを示した。以上の結果より、著者らはリザーバー細胞マーカーとしてのCD32の意義について否定した。どちらの主張が正しいのか、何故このような異なる結果が生じたのかについて、引き続き複数のラボによる検証が必要であろう。

 

鷲崎

Journal : The Journal of Clinical Investigation Volume 128 Number 3 March 2018

Title: HIV latency is reversed by ACSS2-driven histone crotonylation

Authors: Guochun Jiang, Don Nguyen, Nancie M. Archin, Steven A. Yukl, Gema Méndez-Lagares, Yuyang Tang, Maher M. Elsheikh, George R. Thompson III, Dennis J. Hartigan-O’Connor, David M. Margolis, Joseph K. Wong, Satya Dandekar

URL: https://www.jci.org/articles/view/98071#sd

Remarkable point: 

近年、プロモーター領域のヒストンのクロトニル化が遺伝子発現を促進することが明らかにされた。現在までにHIVの潜伏感染にはヒストンのアセチル化、メチル化などのエピジェネティックな修飾が関わっていることがすでに知られている。しかしながら、LTR領域のヒストンのクロトニル化がHIVの活性化に寄与しているのかについては明らかにされていない。そこで筆者はHIV潜伏感染患者のPBMCよりrCD4+ T cellを単離し、Na-Croで処理した。その結果、the crotonyl-CoA–producing enzyme acyl-CoA synthetase short-chain family member 2 (ACSS2)の発現が上昇し、ヒストンのクロトニル化が起こると共にreplication competentなウイルスが誘導されることが明らかにされた。さらに、既存のLRAPKC activatorPEP005Na-Croとを併用すると相乗的にHIVを再活性化することも明らかとなった。

また、SIV感染アカゲザルの腸管でのACSS2の発現を見たところ、急性期で発現が上昇し、慢性期で低下することが明らかとなった。このことからACSS2を介したヒストンのクロトニル化によりin vivoでもウイルスの発現が制御されている可能性が示唆された。このことから、(1)Na-Croが有望なLRAであること、(2)ヒストンのクロトニル化がHIVの活性化状態のコントロールに関わっていることが示された。

 

村田

Journal : The Journal of Immunology 2018 Apr 15;200(8):2714-2726.

Title: Associations of Simian Immunodeficiency Virus (SIV)-Specific Follicular CD8+ T Cells with Other Follicular T Cells Suggest Complex Contributions to SIV Viremia Control

Authors: Mohammad Arif Rahman, Katherine M. McKinnon, Tatiana S. Karpova, David A. Ball, David J. Venzon, Wenjin Fan, Guobin Kang, Qingsheng Li and Marjorie Robert-Guroff

URL: https://www.ncbi.nlm.nih.gov/pubmed/29507105

Remarkable point:

HIV感染において,リンパ濾胞にあるTfh細胞はART治療下でも持続的にウイルス産生する重要な細胞であり、サンクチュアリと考えられている。その一方でその濾胞の胚中心での細胞障害性のCD8+Tcellが確認されている。しかし濾胞内のCD8+Tcellとその他の細胞の関係についてはあまり研究がなされていなかった。この研究で著者らは、SIV/アカゲザルのモデルを用いて、濾胞内のCD8+Tcellviremiaに相関があること、CD8+TcellTfh細胞が分泌するIL-21によってviremiacontrolしていることを明らかにした。

濾胞内での細胞間の関係を明らかにすることは今後ワクチンの開発やリザーバーを排除する新たなストラテジーに有用であると考えられる。

 

 

 


Luncheon seminar


 

Date:2018.05.31

Name: Ayaka Washizaki

Journal : Science translational medicine

Title: TLR7 agonists induce transient viremia and reduce the viral reservoir in SIV-infected rhesus macaques on antiretroviral therapy

Authors: So-Yon Lim, Christa E. Osuna, Peter T. Hraber, Joe Hesselgesser, Jeffrey M. Gerold, Tiffany L. Barnes, Srisowmya Sanisetty, Michael S. Seaman, Mark G. Lewis, Romas Geleziunas, Michael D. Miller, Tomas Cihlar, William A. Lee, Alison L. Hill, James B. Whitney.

URL: http://stm.sciencemag.org/content/10/439/eaao4521

Background: HIV完治実現のため、Shock and kill療法が注目されている。Shock and kill療法に使うLRAとしてはすでに様々なものが注目されているが、未だ完治につながった例はない。

 LRAの候補の一つであるTLR7はすでにHBV治療薬として臨床試験が進んでおり、type I IFNの産生を促す効果があることがわかっている。さらにHIVでもtype I IFNを介したinnate immunityの活性化によりHIV specificCD8が誘導され、同時に潜伏感染細胞の再活性化もできることがex vitroの実験からわかっている。これらのことからTLR7 agonistLRAとして有望視されている。

今回、筆者たちはART下のSIVmac251感染アカゲザルに複数回のTLR7 agonistの経口投与を行い、投与前後のウイルスの再活性化、及びリザーバーサイズの検討を行った

Conclusion: TLR7 agonistを投与すると一時的にPVLの上昇が認められた。さらにTLR7 agonist投与前後のリザーバーサイズを検討してみると、13頭中2頭でリザーバーサイズの顕著な縮小が見られた。この2頭についてはこの論文で行われた全ての実験において潜伏感染細胞の存在が認められなかった。また、ARTを辞めても、CD8 depletionを行なってもウイルスのリバウンドが認められなかった。このことから、TLR7 agonistが非常に有望なLRAであるということが示された。

 

 

Date:2018.6.7

Name:Tomoyuki Miura

Journal: Nature Medicine, 24: 610-616, 2018.

Title: A single injection of crystallizable fragment domainmodified antibodies elicits durable protection from SHIV infection

Authors: Gautam R, Nishimura Y, Gaughan N, Gazumyan A, Schoofs T, Buckler-White A, Seaman MS, Swihart BJ, Follmann DA, Nussenzweig MC, Martin MA

URL: https://www.ncbi.nlm.nih.gov/pubmed/29662199

Background: In the absence of an effective and safe vaccine against HIV-1, the administration of broadly neutralizing antibodies (bNAbs) represents a logical alternative approach to prevent virus transmission. This group previously reported that single intravenous (i.v.) injections of native 3BNC117 or 10-1074 bNAbs prevented virus acquisition in macaques following repeated low-dose (RLD) challenges with tier 2 SHIVAD8-EO as compared to control monkeys that received no anti-HIV-1 neutralizing monoclonal antibodies. Therefore, this group examined two aspects of anti-HIV-1 immunoprophylaxis: (1) the long-term efficacy of the more potent 3BNC117 or 10-1074 bNAbs with the LS substitution in the crystallizable fragment to increase their half-lives infused individually through the i.v. route; and (2) the prevention of virus acquisition via the combination of LS-mutant 3BNC117 and 10-1074 monoclonal antibodies administered subcutaneously (s.c.).

Conclusion: A single infusion of the 10-1074-LS monoclonal antibody protected four of six monkeys challenged on a weekly basis for more than 6 months. In addition and despite volume limitations (1.0 ml), s.c. combination immunoprophylaxis conferred protection in five of six monkeys against RLD challenge for a median of 20 weeks.

 

Date: 20180614

Name: Anna Hu

Journal: Journal of Experimental Medicine

Title: Spatial distribution and function of T follicular regulatory cells in human lymph nodes

Authors: Ismail Sayin, Andrea J. Radtke, Laura A. Vella, Wenjie Jin, E. John Wherry, Marcus Buggert, Michael R. Betts, Ramin S. Herati, Ronald N. Germain, David H. Canaday

URL: http://jem.rupress.org/content/early/2018/05/15/jem.20171940

Background: Follicular Regulatory T (Tfr) cells are an effector subset of regulatory T (Treg) cells. Sharing many characteristics with both Treg and Tfh cells, Tfr cells are also involved in humoral immunity, its principal known function being, to control germinal center responses by suppressing Tfh and B cell activity. Up to this point, it has been proposed that Tfr cells are located inside the germinal centers of lymph nodes and directly suppress Tfh and B cells accordingly. In terms of HIV, Tfr research remains to be an important topic due to its relationship with Tfh cells, a well-known reservoir for latent HIV. Recently, it has also been discovered that Tfr cells also have a potential to be infected with HIV as well and are possibly more permissive to infection than Tfh cells.

Conclusion: Through an examination of the spatial distribution, interacting partners, and function of Tfr cells in human lymph nodes, this paper has suggested two main points from its findings. First, they propose a model where Tfr cells regulate humoral immune response from the “outside-in.” This suggestion is in fact, a complete contradiction to earlier findings; however, this suggestion is supported by their observation that Tfr cells are mostly located in the T-B border and not the germinal center. Additionally, based on their finding of an enrichment of CD69+ Tfr cells at the T-B border and the ability for these CD69+ Tfr cells to produce GARP (a protein critical for the surface expression of latent TGF-b), they propose that Tfr cells may modulate antibody responses in a TGF-b dependent manner in mesenteric lymph nodes.

 

Date: 20180621

Name: Ai Himeno

Journal: Journal of Virology

Title: A novel strategy to adapt SHIV-E1 carrying env from an RV144 volunteer to rhesus macaques: coreceptor switch and final recovery of a pathogenic virus with exclusive R5 tropism 

Authors: Scinto HB, Gupta S, Thorat S, Mukhtar MM, Griffiths A, Delgado J, Plake E, Vyas HK, Strickland A, Byrareddy SN, Montefiori DC, LaBranche C, Pal R, Treece J, Orndorff S, Ferrari MG, Weiss D, Chenine AL, McLinden R, Michael N, Kim JH, Robb M, Rerks-Ngarm S, Pitisuttithum P, Nitayaphan S, Ruprecht RM.

URL: http://jvi.asm.org/content/early/2018/05/03/JVI.02222-17.long

Background: Definitive experiments to decipher the mechanisms of the partial protection observed in RV144 require passive immunization studies in NHPs with a relevant test virus. They have generated such a virus by inserting env from an RV144 placebo recipient into a SHIV backbone with HIV-like LTRs (with two NFkB site). Furthermore, they devised a novel strategy, which in vivo transfection by intra-muscular inoculation of infectious proviral DNA and repeated administration of cell-free virus under ablation of both arms of adaptive immunity (depletion of CD8+Tcell, NK cell and B cell).

Conclusion: They report the successful construction, adaptation, and characterization of a SHIV-E that carries an HIV CRF01_AE envelope isolated. The final SHIV-E1p5 isolate, an exclusively R5 tropic virus with tier 2 neutralization phenotype, grown in rhesus PBMC, was mucosally transmissible and pathogenic. Earlier SHIV-E passages showed coreceptor switch, again mimicking HIV biology in humans. Their series of SHIV-E strains mirrors HIV transmission and disease progression in humans. SHIV-E1p5 represents a biologically relevant tool to assess prevention strategies.

 

 

Date: 20180628

 

Name: Ejikeugwu Chika (Ph.D.)

 

Journal : Antiviral Research

 

Title: Adipocytes Impair Efficacy of Antiretroviral Therapy

 

Authors: Jacob Couturier, Lee C. Winchester, James W. Suliburk, Gregory K. Wilkerson, Anthony T. Podany, Neeti Agarwal, Corrine Ying Xuan Chua, Pramod N. Nehete, Bharti P. Nehete, Alessandro Grattoni, K. Jagannadha Sastry, Courtney V. Fletcher, Jordan E. Lake, Ashok Balasubramanyan and Dorothy E. Lewis

 

URL: https://www.ncbi.nlm.nih.gov/pmc/articles/PMC5955795/

 

Background: HIV persistence is facilitated by inadequate distribution of antiretroviral drugs in cellular and anatomic reservoirs. For example, incomplete suppression of viral replication in lymph nodes is associated with decreased drug penetration. Adequate distribution of antiretroviral drugs to infected cells in HIV patients is critical for viral suppression. In humans and primates, HIV- and SIV-infected CD4 T cells in adipose tissues have recently been identified as reservoirs for infectious virus. To better characterize adipose tissue as a pharmacological sanctuary for HIV-infected cells, in vitro experiments were conducted to assess antiretroviral drug efficacy in the presence of adipocytes, and drug penetration in adipose tissue cells (stromal-vascular-fraction cells and mature adipocytes) was examined in treated humans and monkeys.

 

Conclusion: The study concluded that adipocytes significantly impact antiretroviral functions and that INSTIs penetrate adipose tissue more consistently than N(t)RTIs. Drug penetration into AT is important not only for controlling AT HIV reservoirs, but also because other major HIV reservoirs - such as lymph nodes, GALT and bone marrow - are lipid-rich or intricately associated with adipocytes/AT function. Complete targeting of viral reservoirs with ART should take into consideration the role of adipose tissue penetration and lipid-rich milieus.

 

 

 

Date:2018.7.5

Name:Hisatoshi Shida

Journal: Nature Medicine, 24, 847856, 2018.

Title: HIV vaccine candidate activation of hypoxia and the inflammasome in CD14+ monocytes is associated with a decreased risk of SIVmac251acquisition

Authors: Vaccari MFourati SGordon SNBrown DRBissa MSchifanella LSilva de Castro IDoster MNGalli VOmsland MFujikawa DGorini GLiyanage NPMTrinh HVMcKinnon KMFoulds KEKeele BFRoederer MKoup RAShen XTomaras GDWong MPMunoz KJGach JSForthal DNMontefiori DCVenzon DJFelber BKRosati MPavlakis GNRao MSekaly RPFranchini G.

URL:https://www.ncbi.nlm.nih.gov/pubmed/29785023

Background: RV144 trial that is composed with priming of canarypox (ALVAC) vector expressing HIV-1 env followed by booster of gp120/alum lowered infection rate by 30%. To improve vaccine efficacy, the authors tested the ability of ALVACSIV, DNASIV and Ad26SIV vaccine prime modalities together with two ALVACSIV+ gp120 protein boosts to reduce the risk of SIVmac251 acquisition in rhesus macaques.

Conclusion: They found that the DNA and ALVAC prime regimens were effective, but the Ad26 prime was not. The activation of hypoxia and the inflammasome in CD14+CD16− monocytes, gut-homing CCR5-negative CD4+ T helper 2 (TH2) cells and antibodies to variable region 2 correlated with a decreased risk of SIVmac251 acquisition. By contrast, signal transducer and activator of transcription 3 activation in CD16+ monocytes was associated with an increased risk of virus acquisition. The Ad26 prime regimen induced the accumulation of CX3CR1+CD163+ macrophages in lymph nodes and of long-lasting CD4+ TH17 cells in the gut and lungs. Our data indicate that the selective engagement of monocyte subsets following a vaccine prime influences long-term immunity, uncovering an unexpected association of CD14+ innate monocytes with a reduced risk of SIVmac251 acquisition.

 

 

Date: 19.07.2018

 

Name: YALÇIN PISIL

 

Journal : Journal of Virology, August 2017,Volume 91,     Issue 15, e00677-17

 

Title: Reducing V3 Antigenicity and Immunogenicity on Soluble, Native-Like HIV-1 Env SOSIP Trimers

 

Authors: Rajesh P. Ringe,a Gabriel Ozorowski,b Kimmo Rantalainen,b Weston B. Struwe,c Katie Matthews,a* Jonathan L. Torres,b Anila Yasmeen,a Christopher A. Cottrell,b Thomas J. Ketas,a Celia C. LaBranche,e David C. Montefiori,d Albert Cupo,a Max Crispin,c,d Ian A. Wilson,b Andrew B. Ward,b Rogier W. Sanders,a,f P. J. Klasse,a John P. Moorea

 

URL: http://jvi.asm.org/content/91/15/e00677-17.full

 

Background: One successful stabilization strategy (SOSIP) involves introduction of an intermolecular disulfide bond (SOS) to link gp120 and gp41, a point substitution (I559P, i.e., IP) to maintain the gp41 subunits in their pre-fusion form, and truncation at residue 664 to improve trimer solubility.

 

SOSIP trimers display the epitopes for multiple bNAbs but can also expose binding sites for some types of non-NAbs. Non-Nabs is binding to epitopes in the gp120 V3 region.

 

It is presently uncertain whether antibodies against V3 can interfere with the induction of NAbs, but there are good arguments in favor of suppressing such “off-target” immune responses.

 

Therefore, They have assessed how to minimize the exposure of V3 non-NAb epitopes and thereby reduce their immunogenicity by introducing N-glycans within the V3 region of BG505 SOSIP trimers.

 

Conclusion: A rabbit immunogenicity study showed that the glycan-modified SOSIP.664- E64K.M1M7 and parental SOSIP.664 trimers induced comparable titers of autologous tier-2 NAbs, but the tier-1 NAb titers elicited by the modified trimers were reduced.

 

Reducing the immunogenicity of V3 and other non-NAb epitopes on germ line-targeting SOSIP trimers, including by using the glycan-masking method, may be worthwhile.

 

 

Date:2018.7.26

 

Name: Megumi Murata

 

Journal : Nature Immunology

 

Title: Resistance of HIV-infected macrophages to CD8+ T lymphocyte–mediated killing drives activation of the immune system

 

Authors: Kiera L. Clayton, David R. Collins, Josh Lengieza, Musie Ghebremichael, Farokh Dotiwala, Judy Lieberman and Bruce D. Walker

 

URL: https://www.nature.com/articles/s41590-018-0085-3

 

Background: It has been suggested that infected macrophages contribute to the persistence and pathogenesis of HIV. Infected macrophages efficiently disseminate virus to CD4+ T cells via neutralization-evading cell-to-cell spread. Studies of animal models of HIV infection further support the proposal of in vivo infection and persistence of macrophages, even during combination antiretroviral therapy. CD8+ cytotoxic T lymphocytes (CTLs) control viral levels during and chronic stages of HIV infection. However, most studies have focused on the control of infected CD4+ T cells by CTLs, with less focus on infected macrophages. The efficiency of CTL-mediated killing of HIV-infected CD4+ T cells relative to that of HIV-infected macrophages is poorly characterized.

 

Improved understanding of CTL responses to HIV-infected macrophages will inform strategies to eliminate this population and combat HIV-associated inflammation.

 

Conclusion: They characterized and compared the interactions of HIV-specific ex vivo CTLs with HIV-infected CD4+ T cell targets and macrophage targets. They found that macrophages were less susceptible to CTL-mediated killing than were CD4+ T cells and that this was an intrinsic characteristic of macrophages independent of HIV infection. Although CTL cytotoxic granules mediated the killing of both cell types, CD4+ T cells underwent rapid caspase-independent cell death, while macrophages underwent a slower granzyme B– and caspase-3-dependent death. Inefficient CTL-mediated killing of macrophages drove prolonged formation of synapses between effector cells and target cells, greater secretion of IFN-γ (a major macrophage-activating cytokine) from CTLs and induction of macrophage pro-inflammatory chemokines that recruited monocytes

 

and T cells. Inefficient killing of macrophages by CTLs might contribute to chronic inflammation, a hallmark of chronic disease caused by HIV.

 

 

Date: 2018.09.06

 

Name: Wei Keat TAN

 

Journal: Science Immunology

 

Title: CD4+ T cell–mediated HLA class II cross-restriction in HIV controllers

 

Authors: Moran Galperin, Carine Farenc, Madhura Mukhopadhyay, Dhilshan Jayasinghe, Amandine Decroos, Daniela Benati1, Li Lynn Tan, Lisa Ciacchi, Hugh H. Reid, Jamie Rossjohn, Lisa A. Chakrabarti and Stephanie Gras

 

URL: http://immunology.sciencemag.org/content/3/24/eaat0687

 

Background: 

 

The rare patients, a.k.a elite controllers, who are able to spontaneously control HIV replication in the absence of therapy show signs of a particularly efficient cellular immune response. Previously, a set of unusual T-cell (public TCRs) receptors found in the CD4+ T cells of most elite controllers is able to recognize low levels of HIV peptide and recognize an array of HLAs. In the current study, they, therefore, observed public TCRs’ effects on immune response to infection, and what enables them to be activated by multiple HLAs.

 

Conclusion: 

 

In brief, this paper reported that the high-affinity public TCRs conferred anti-HIV cytotoxic activity to heterologous CD4+ and CD8+ T cells across multiple HLA-DR molecules. CD4+ and CD8+ T cells armed with one of the public TCRs (selected based on high frequency in elite controllers) effectively recognized and killed HIV-infected dendritic cells, at least in in vitro. This paper also determined the structure of the complexes formed when public TCRs interact with different HLAs holding bits of protein from HIV, and found that each TCR’s contact was primarily with the HIV-derived peptide rather than with the HLA itself.

 

 

 

Date:2018.09.13

 

Name:山浦 瑞樹

 

Journal : PLOS ONE July.2018

 

Title: Brain is a potential sanctuary for subtype C HIV-1 irrespective of ART treatment outcome

 

Authors: For Yue Tso,Guobin Kang,Eun Hee Kwon,Peter Julius,Qingsheng Li,John T. West,Charles Wood

 

 URL: https://journals.plos.org/plosone/article?id=10.1371/journal.pone.0201325

 

Background:HIV根治を目指すうえで、HIVウイルスのリザーバーの存在は重要な因子になる。Koenig Sらが1986年にScience誌で「脳は数あるHIVのリザーバーの一つである」と報告して以来、複数のラボで数多くの研究が為されてきた。ところが、多くの研究で用いられてきた検体はほとんどがSubtype Bと呼ばれる、欧米に患者数が多い検体であり、世界全体の約50%以上の患者が感染しているSubtype Cの検体についてはほとんど為されてこなかったのが現状である。

 

本研究ではSubtype Cに感染し、その後cART療法を受けた患者八名の検体を用いた。そして果たしてcARTの成功と失敗とHIVウイルスが脳をリザーバーにするのか、否かについて研究し、HIVstrainによってリザーバーの指向性があるのかについて先行研究から比較検討を行った。

 

Conclusion:本研究の結果として、HIVウイルスはcARTの成功と失敗に関わらず脳をリザーバーにしていることが示された。加えて、Subtype Bを用いた先行研究でも今回と同様の結果が得られていることから、strainによるリザーバーの指向性は無いと著者らは結論付けている。今回のようにSubtype Cを用いたHIVリザーバーの研究は未知の領域が広い。このテーマに対するアプローチは引き続き複数のラボで行われる必要があるだろう。

 

 

 

Date:2018/09/27

 

Name:Li Jialin

 

Journal : AIDS 2018, 32:555563

 

Title: Development of broad neutralization activity in simian/human immunodeficiency virus-infected rhesus macaques after long-term infection

 

Authors: Nan Gao, Wei Wang, Chu Wang, Tiejun Gu, Rui Guo, Bin Yu, Wei Kong, Chuan Qin, Elena E. Giorgi, Zhiwei Chen, Samantha Townsley, Shiu-Lok Hu, Xianghui Yu, and Feng Gao

 

URL: https://insights.ovid.com/pubmed?pmid=29239895

 

Background: Nonhuman primates (NHPs) are the only animal model that can be used to evaluate protection efficacy of HIV-1 envelope vaccines. However, whether broadly neutralizing antibodies (bnAbs) can be elicited in NHPs infected with SHIV has not been fully understood. This study is to investigate whether broad neutralization activities were developed in SHIV- infected macaques after long-term infection as in humans.

 

Conclusion: With their results, which demonstrate that bnAbs targeting common HIV-1 epitopes can be elicited in SHIV1157ipd3N4-infected macaques as in humans after 46 years of infection, and SHIV/NHP can serve as an ideal model to study bnAb maturation.