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Studies on cellular reservoirs of HIV-1 in patients on antiretroviral therapy / Kelly Miriam Cheney.Cheney, Kelly Miriam January 2005 (has links)
Amendments appended. / Bibliography: leaves 140-165. / xi, 165 leaves : ill. ; 30 cm. / Title page, contents and abstract only. The complete thesis in print form is available from the University Library. / Thesis (Ph.D.)--University of Adelaide, Dept. of Microbiology and Immunology, 2005
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Development of spray-dried polycaprolactone-drug loaded nanoparticles towards improving current HIV chemotherapy29 July 2013 (has links)
M.Sc. (Chemistry) / Human immunodeficiency virus (HIV) is continuously rewriting medical history as one of the diseases affecting humankind. Current treatments available for HIV, namely antiretrovirals (ARVs), do not completely eradicate the virus from the body, leading to life time commitment. Many ARVs suffer from high toxicities and unpleasant side effects; as a result many patients do not adhere to the treatment. Nanoparticles (NPs) used as drug delivery systems (DDS) hold tremendous potential, since they can easily protect the drug from external environment and enter the human cells to deliver drugs. Therefore, the main objective of this work was to load two ARVs, namely lamivudine (LAM) and efavirenz (EFV), into a biodegradable, biocompatible poly(epsilon-caprolactone) (PCL) polymer based NPs. LAM is a hydrophilic drug suffering from low half life of 5 to 7 hours and many unpleasant side effects. EFV is a hydrophobic drug suffering from low aqueous solubility (4 μg/ml), which leads to a limited oral absorption and low bioavailability (40-45%).
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Treatment of HIV infection with didanosive and foscarnet / by Graeme John Moyle.Moyle, Graeme John. January 1995 (has links)
Copies of author's previously published works inserted. / Bibliography: leaves 230-282. / 291 leaves : / Title page, contents and abstract only. The complete thesis in print form is available from the University Library. / Covers clinical data relating to trials with two antiretroviral agents, didanosine and foscarnet, conducted at St Stephen's clinic, London, discussing aspects of their therapetic efficacy, effect on survival, clinical and laboratory tolerability. / Thesis (M.D.)--University of Adelaide, Dept. of Medicine, 1995
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Mechanism study of a small molecule F18 as a novel anti-HIV-1 non-nucleoside reverse transcriptase inhibitorLu, Xiaofan., 陆小凡. January 2012 (has links)
Non-nucleoside reverse transcriptase inhibitor (NNRTI) is one of the key components of antiretroviral drug regimen against human immunodeficiency virus type-1 (HIV-1) replication. However, the low genetic barriers to drug-resistance or cross-resistance, side effects, as well as the unaffordable cost of NNRTIs compromise their clinical usage. Therefore, to develop novel NNRTIs with potent antiviral activity against HIV-1 becomes a major concern in the treatment and prevention of HIV/AIDS.
(+)-Calanolide A, which is a natural product initially extracted from the tropical rainforest tree Calophyllum lanigerum, was identified as an attractive NNRTI against HIV-1 despite virus strains containing drug-resistant K103N/Y181C mutations. In this study, a chemical library was constructed based on the three chiral carbon centers of (+)-Calanolide A. After screening the activity against HIVNL4-3 wild-type and several NNRTI-resistant pseudoviruses, a small molecule 10-chloromethyl-11- demethyl-12-oxo-calanolide A (F18) was identified as novel NNRTI with promising anti-HIV efficacy.
Further studies were performed to investigate the antiviral breadth, drug resistance profile and underlying mechanism of the action of F18. F18 consistently displayed a potent activity against primary HIV-1 isolates including various subtypes of M group, CRF01_AE, and laboratory-adapted drug-resistant viruses in PBMC based assay. Moreover, F18 displayed distinct profiles against 17 NNRTI-resistant pseudoviruses, with an excellent potency especially against one of the most prevalent strains with the Y181C mutation (EC50=1.0nM) in cell line based assay, which was in stark contrast from the extensively used NNRTIs nevirapine and efavirenz. F18-resistant viruses were induced by in vitro serial passages, and mutation L100I was appeared to be the dominant contributor to F18-resistance, further suggesting a binding motif different from nevirapine and efavirenz. The efficacy of F18 was non-antagonistic when used in combination with other antiretrovirals against both wild-type and drug-resistant viruses in infected PBMCs. Interestingly, F18 displayed a highly synergistic antiviral effect with nevirapine against nevirapine-resistant virus (Y181C). Furthermore, in silico docking analysis suggested that F18 may bind to the HIV-1 reverse transcriptase in a way different to other NNRTIs. For the potential as an anti-HIV-1 microbicide, F18 also showed the stable and rapid release, as well as the sustained antiviral activity against HIV-1 wild-type virus in a formulation temperature-sensitive acidic gel.
In summary, this study presents F18 as a new potential drug for clinical use and also underlies new mechanism-based design for future NNRTI. / published_or_final_version / Microbiology / Doctoral / Doctor of Philosophy
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Factors that influence adherence to highly active antiretroviral therapy (HAART).Naicker, Michaela Helene. January 2011 (has links)
HIV/AIDS remains one of the most pressing challenges facing South African society. South Africa has the highest number of people living with HIV as well as the highest number of people on HIV treatment globally, yet only 37% of persons eligible for treatment have access to treatment. The advent of HAART ushered in a new era in the treatment of HIV infection. HIV infection was no longer a life threatening terminal illness, HIV/AIDS became a chronic manageable disease. The full clinical benefit of HAART can only be achieved with near perfect adherence i.e. > 95%. This means taking the medication exactly as prescribed; on time, no missed doses, every day, lifelong. No other chronic medication requires such stringent adherence rates for optimal therapeutic benefit, which may mean the choice between life and death. Achieving near perfect adherence poses a serious challenge to health service providers and persons on treatment as typical adherence rates for medication prescribed over long periods are in the 50 – 75 % range. Persons on HAART live with the additional burden of drug resistance and limited treatment options if near perfect adherence rates are not achieved. The purpose of this qualitative study was to explore the factors that influence adherence to HAART. These factors may be related to the person, the health care team and system, the treatment regimen, the social and economic environment or to the effects of HIV disease. Factors may either negatively or positively influence a person’s ability to adhere optimally to their prescribed treatment. A small sample of thirteen participants were purposefully selected for this study. Data was collected using in-depth interviews which were tape recorded and transcribed for thematic analysis. The value of this study is that it may assist health care providers, persons on treatment and the health care system to better comprehend the challenges of lifelong optimal adherence to HAART. / Thesis (M.A.)-University of KwaZulu-Natal, Durban, 2011.
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Application and engineering of ribosome-inactivating proteins for targeting immunodeficiency virus / CUHK electronic theses & dissertations collectionJanuary 2014 (has links)
Ribosome-inactivating proteins (RIPs) are cytotoxins that remove a specific adenine from the sarcin-ricin loop (SRL) of large ribosomal RNA and in turn inhibit protein synthesis. Apart from N-glycosidase activity, some RIPs are found to possess antiviral activity and the suppression on human immunodeficiency virus (HIV) has been extensively studied. / Maize RIP stands out from other members for having an internal inactivation region and requires proteolytic removal to regain full activity. We have exploited the innate regulatory mechanism of maize RIP and increased its specificity towards HIV by adding the HIV protease recognition site to the inhibitory segment. Our results demonstrated the wild-type maize RIP is inhibitory on simian immunodeficiency virus (SIV) replication in rhesus macaque and showed the HIV sensitive variant undergoes specific proteolytic activation upon viral infection and exerts enhanced in vitro antiviral effects. Therapeutic applications of RIPs are often restricted by short in vivo half-life and strong allergic responses and we attempted to improve the therapeutic potential of maize RIP by coupling with polyethylene glycol (PEG). Two mutants were generated for PEGylation and the resultant MOD-PEG₂₀ₖ variant was shown to be less sensitive to antibody recognition and has a prolonged plasma half-life, suggesting it may have enhanced therapeutic values. Besides, the applicability of protease-activation system in RIPs without inactivation loop was tested using ricin A chain (RTA) as the test case and HIV recognition sites were introduced either within or at C-terminus of the protein. The C-terminal RTA variants were specifically processed and had the anti-HIV activity increased in HIV-infected cells. / The present work illustrates the potential development of maize RIP as an anti-HIV agent and shows PEGylation can serve to enhance the protein for in vivo applications. Besides, the engineering of RTA with HIV recognition site suggests the potential of the protease-activation strategy to other RIPs for activity control. / 核糖體失活蛋白(RIPs)是一種細胞毒素蛋白,能特異地水解核糖體sarcin-ricin環(SRL),通過脫嘌呤抑制核糖體的蛋白合成功能。除此功能以外,很多RIP還具有抗病毒的活性,如抗人免疫缺陷病毒(HIV)的活性。 / 玉米RIP與其他的RIP不同,它含有一段內部失活結構域,需通過蛋白水解作用移除該結構域才能成為活性體。我們利用玉米RIP的這一特性,通過對內部結構域的改造,獲得了兩個可被HIV蛋白酶特異識別的突變體。體外實驗証明HIV可以特異地識別突變體上的蛋白酶切割位點,從而將其啟動產生抗病毒活性。另外,我們以蓖麻毒素A鏈(RTA)為例,分別於蛋白質的內部和碳端插入HIV識別序列,驗證了蛋白酶啟動系統在沒有內部失活結構域的RIP中,也能通過HIV蛋白酶的切割而活化並取得抗病毒活性。我們還揭示玉米RIP活性體可以有效抑制猿免疫缺陷病毒(SIV)在感染恒河猴體內的複制。此外,我們嘗試通過與聚乙二醇(PEG)融合來優化玉米RIP的免疫原性和半衰期,成功製備了兩種融合突變體,MOD-PEG₂₀ₖ顯示較不容易被抗體識別且延長了血液半衰期。 / 綜上所述,我們的研究表明玉米RIP作為抗HIV抑制劑具有良好的研發前景,而RTA的改造展示蛋白酶啟動系統可應用於其他RIP,同時我們還證明了PEG修飾可以很好的應用於蛋白類藥物的研發。 / Au, Ka Yee. / Thesis M.Phil. Chinese University of Hong Kong 2014. / Includes bibliographical references (leaves 84-95). / Abstracts also in Chinese. / Title from PDF title page (viewed on 17, October, 2016). / Detailed summary in vernacular field only. / Detailed summary in vernacular field only. / Detailed summary in vernacular field only.
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Synthesis and evaluation of novel HIV-1 enzyme inhibitorsOlomola, Temitope Oloruntoba January 2011 (has links)
This study has involved the design, synthesis and evaluation of novel HIV-1 enzyme inhibitors accessed by synthetic elaboration of Baylis-Hillman adducts. Several series of complex coumarin-AZT and cinnamate ester-AZT conjugates have been prepared, in high yields, by exploiting the click reaction between appropriate Baylis-Hillman derived precursors and azidothymidine (AZT), all of which have been fully characterised using spectroscopic techniques. These conjugates, designed as potential dual-action HIV-1 inhibitors, were tested against the appropriate HIV-1 enzymes, i.e. HIV-1 reverse transcriptase and protease or HIV-1 reverse transcriptase and integrase. A number of the ligands have exhibited % inhibition levels and IC50 values comparable to drugs in clinical use, permitting their identification as lead compounds for the development of novel dual-action inhibitors. In silico docking of selected ligands into the active sites of the respective enzymes has provided useful insight into binding conformations and potential hydrogen-bonding interactions with active-site amino acid residues. A series of furocoumarin carboxamide derivatives have been synthesised in four steps starting from resorcinol and these compounds have also been tested for HIV-1 integrase inhibition activity. The structures of unexpected products isolated from Aza-Baylis-Hillman reactions of N-tosylaldimines have been elucidated by spectroscopic analysis, and confirmed by single crystal X-ray analysis. A mechanism for what appears to be an unprecedented transformation has been proposed. Microwave-assisted SeO₂ oxidation of Baylis-Hillman-derived 3-methylcoumarins has provided convenient and efficient access to coumarin-3-carbaldehydes, and a pilot study has revealed the potential of these coumarin-3-carbaldehydes as scaffolds for the construction of tricyclic compounds. The HCl-catalysed reaction of tert-butyl acrylate derived Baylis-Hillman adducts has been shown to afford 3-(chloromethyl)coumarins and α-(chloromethyl)cinnamic acids, the Zstereochemistry of the latter being established by X-ray crystallography. ¹H NMR-based experimental kinetic and DFT-level theoretical studies have been undertaken to establish the reaction sequence and other mechanistic details. Base-catalysed cyclisation on the other hand, has been shown to afford 2H-chromene rather than coumarin derivatives.
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Influence of non-synonymous sequence mutations on the architecture of HIV-1 clade C protease receptor site : docking and molecular dynamics studiesOnywera, David Harris January 2014 (has links)
Despite the current interventions to avert contagions and AIDS-related deaths, sub-Saharan Africa is still the region most severely affected by the HIV/AIDS pandemic, where clade C is the dominant circulating HIV-1 strain. The pol-encoded HIV-1 protease enzyme has been extensively exploited as a drug target. Protease inhibitors have been engineered within the framework of clade B, the commonest in America, Europe and Australia. Recent studies have attested the existence of sequence and catalytic disparities between clades B and C proteases that could upset drug susceptibilities. Emergence of drug-resistant associated mutations and combinatorial explosions due to recombination thwarts the attempt to stabilize the current highly active antiretroviral therapy (HAART) baseline. The project aimed at identifying the structural and molecular mechanisms hired by mutants to affect the efficacies of both FDA approved and Rhodes University (RU)-synthesized inhibitors, in order to define how current and or future drugs ought to be modified or synthesized with the intent of combating drug resistance. The rationale involved the generation of homology models of the HIV-1 sequences from the South African infants failing treatment with two protease inhibitors: lopinavir and ritonavir (as monitored by alterations in surrogate markers: CD4 cell count decline and viral load upsurge). Consistent with previous studies, we established nine polymorphisms: 12S, 15V, 19I, 36I, 41K, 63P, 69K, 89M, and 93L, linked to subtype C wild-type; some of which are associated with protease treatment in clade B. Even though we predicted two occurrence patterns of M46I, I54V and V82A mutations as V82A→I54V→M46I and I54V→V82A→M46V, other possibilities might exist. Mutations either caused a protracted or contracted active site cleft, which enforced differential drug responses. The in silico docking indicated susceptibility discordances between clades B and C in certain polymorphisms and non-polymorphisms. The RU-synthesized ligands displayed varied efficacies that were below those of the FDA approved protease inhibitors. The flaps underwent a wide range of structural motions to accommodate and stabilize the ligands. Computational analyses unravelled the need for these potential drugs to be restructured by (de novo) drug engineers to improve their binding fits, affinities, energies and interactions with multiple key protease residues in order to target resilient HIV-1 assemblages. Accumulating evidences on contrasting drug-choice interpretations from the Stanford HIVdb should act as an impetus for the customization of a HIVdb for the sub-Saharan subcontinent.
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Search of inhibitors that target HIV pre-mRNA splicing to overcome drug resistance.January 2012 (has links)
引發獲得性免疫缺陷綜合癥(AIDS)的人類免疫缺陷病毒(HIV)是一種逆轉錄病毒。過去的十餘年間,高效抗逆轉錄病毒治療療法(HARRT),在抗病毒感染方面取得了很大的成功。高效抗逆轉錄病毒治療療法是一種將多種抗逆轉錄病毒藥物複合的藥物聯用療法。然而,因為病毒的逆轉錄過程極易突變,導致HIV已經可以對大多數使用的抑製藥物產生抗藥性。因此,有越來越多的需要去尋找新型的抗病毒複製機理,例如將人體細胞蛋白作為載體,來達到克服病毒抗藥性的目的。 / HIV-1的複製離不開宿主細胞的剪接因子,例如SR蛋白。選擇性剪接因子ASF/SF2,一個典型的調控pre-RNA剪接的SR蛋白,在HIV-1的pre-mRNA剪接和複製中起到了很重要的調控作用。ASF/SF2和其他SR蛋白一樣,都被丝氨酸/苏氨酸蛋白激酶(SRPK)磷酸化,磷酸化位點位於C端的丝氨酸/苏氨酸結構域(RS domain)。SRPK通過磷酸化來調節ASF/SF2在細胞中的分佈。對於SRPK 和ASF/SF2複合物的結構學和功能學研究指出,ASF/SF2的docking motif和SRPK1的遠離活性位點的docking groove存在很強的相互作用。而這種相互作用是調節磷酸化過程關鍵。所以,在我們的研究過程中,我們希望通過阻斷2個蛋白的相互作用來干擾ASF/SF2的磷酸化,進而抑制其在HIV-1 pre-mRNA剪接過程中的活性。 / 我們採用以結構為基礎的藥物模擬篩選,來選擇潛在的抑制物,達到通過抑制物與docking groove的相互作用來阻斷ASF/SF2和SRPK1的相互作用,以達到抑制磷酸化的目的。我們使用的數據庫來自于ZINC數據庫(UCSF),包括天然產物數據庫和SPECS。我們採用AutoDock Vina 和AutoDock 4.2 二個模擬軟件來栓選數據庫中351473个化合物。并從中選出50個潛在的化合物用作之後的化學生物學測試。體外的激酶活性試驗顯示,6個化合物對ASF/SF2的磷酸化有抑製作用。 / 體外的HIV-1 pre-mRNA剪接實驗顯示,5個化合物在逆轉錄PCR(RT-PCR)中有一定得抑制效果。和DMSO對照組相比,在抑製劑作用下剪接產物的生成被抑制。HIV-1病毒合胞體感染實驗顯示,有一個化合物對病毒的感染起到了一定的抑制作用。 / 其他的測試實驗還在進行中,包括對SRPK1和抑制物複合物的結構研究,從而更好的研究抑制物的作用機理。以及,採用表面等離子共振波譜來進行動力學研究和其他關於化合物在病毒複製過程中的實驗測試。 / Human immunodeficient virus (HIV) is a retrovirus that cause acquired immunodeficiency syndrome (AIDS). Highly active antiretroviral therapy (HAART) is a treatment of HIV infection that uses combinations of antiretroviral drugs and has achieved great success in the past two decades. However, since the reverse transcription process of viral RNA is notoriously prone to error, HIV-1 can acquire resistance to nearly all known inhibitors and has started to develop resistance to HAART. Therefore, there is an ongoing search for new drugs with novel inhibitory mechanism such as targeting cellular proteins essential for HIV-1 replication to overcome drug resistance of the virus. / HIV-1 mRNA undergoes complex splicing and the expression of the integrated HIV-1 provirus is largely dependent on the host’s splicing machinery which assembly requires splicing factors such as serine-arginine rich proteins (SR proteins). Alternative splicing factor/splicing factor 2 (ASF/SF2), a prototypic SR protein that is essential for pre-mRNA splicing, has been shown to play critical roles during HIV-1 pre-mRNA splicing and replication. ASF/SF2, like other SR proteins, is phosphorylated by SR protein-specific kinases (SRPKs) at its C-terminal arginine/serine (RS) domain, which governs its localization and metabolism. Structural and functional studies of SRPK1 in complex with ASF/SF2 has revealed that a docking groove on SRPK1 that is distal to the active site interacts strongly with a docking motif and the RS domain of ASF/SF2, leading to high affinity binding as well as regulating the mechanism of phosphorylation. In this study, we propose that by blocking this interaction, we might interfere the phosphorylation of ASF/SF2 and inhibit its activity during splicing of HIV-1 pre-mRNA. / Structure-based in silico screening method is adopted to identify potential inhibitors that bind to the docking groove of SRPK1 to block the binding and phosphorylation of ASF/SF2. The compound libraries being used include the Natual Products Database and SPECS database from ZINC (UCSF). 351,473 compounds have been screened using the program Autodock Vina as well as Autodock 4.0. Until now 50 potential candidates of inhibitor have been selected for biochemical analyses. In vitro kinase assays showed that six compounds exhibit inhibitory activity against the phosphorylation of ASF/SF2. / To test the effect of the selected inhibitors on the splicing of HIV-1 mRNA, ex vivo splicing assay has been performed. Current results showed that the synthesis of splicing products extracted from drug-treated cells was less efficient when compared to untreated cells. Biological assays testing the inhibitory effects of the compounds on viral infection are currently underway. Our preliminary result suggested that one of the compounds could indeed inhibit HIV-1 viral infection. / Other biochemical and biological analyses including structural study of kinase-inhibitor complexes to understand the mode of inhibition; measurement of binding kinetics using surface plasmon resonance spectroscopy (SPR); and biological assays testing the inhibitory effects of the compounds on replication are underway. / Detailed summary in vernacular field only. / Detailed summary in vernacular field only. / Detailed summary in vernacular field only. / Detailed summary in vernacular field only. / Detailed summary in vernacular field only. / Yu, Xiyao. / Thesis (M.Phil.)--Chinese University of Hong Kong, 2012. / Includes bibliographical references (leaves 95-107). / Abstracts also in Chinese. / Abstract --- p.I / 摘要 --- p.III / Acknowledgements --- p.V / TABLE OF CONTENTS --- p.VI / LIST OF FIGURES --- p.IX / LIST OF TABLES --- p.XI / Chapter Chapter I --- : Introduction --- p.1 / Chapter 1.1 --- HIV, HAART and HIV Drug Resistance --- p.2 / Chapter 1.2 --- HIV-1 alternative splicing mechanism --- p.9 / Chapter 1.3 --- SR Protein Family --- p.13 / Chapter 1.4 --- Functional roles of SR protein in HIV pre-mRNA splicing --- p.16 / Chapter 1.5 --- Phosphorylation States of SR Proteins --- p.18 / Chapter 1.6 --- SR protein Kinase --- p.20 / Chapter 1.7 --- Interaction between SRPK1 and ASF/SF2 --- p.23 / Chapter 1.8 --- IDC16 and SPRIN340 --- p.26 / Chapter 1.9 --- Structure-based drug screening --- p.27 / Chapter 1.10 --- AutoDock Suite --- p.29 / Chapter 1.11 --- Kinase-substrate interaction inhibitors --- p.30 / Chapter 1.12 --- Focus of study --- p.34 / Chapter Chapter II --- : Materials and Methods --- p.35 / Chapter 2.1 --- Materials --- p.36 / Chapter 2.1.1 --- Bacterial strain --- p.36 / Chapter 2.1.2 --- Antibodies --- p.36 / Chapter 2.1.3 --- Cell line --- p.36 / Chapter 2.1.4 --- Plasmid --- p.36 / Chapter 2.1.5 --- Reagents --- p.38 / Chapter 2.2 --- Expression and purification of Recombinant protein --- p.38 / Chapter 2.3 --- In silico screening of inhibitors --- p.44 / Chapter 2.4 --- Kinase Glo Assay --- p.45 / Chapter 2.5 --- In vitro kinase assay --- p.45 / Chapter 2.6 --- Cell Culture --- p.46 / Chapter 2.7 --- MTT Assay --- p.46 / Chapter 2.8 --- Immunocytochemistry --- p.47 / Chapter 2.9 --- Ex vivo splicing assay --- p.47 / Chapter 2.10 --- Surface plasmon resonance spectroscope --- p.48 / Chapter Chapter III --- : Results --- p.50 / Chapter 3.1 --- In silico screening of inhibitors --- p.51 / Chapter 3.2 --- Selected Compounds Inhibits SRPK1 in Vitro --- p.60 / Chapter 3.2.1 --- Protein purification --- p.60 / Chapter 3.2.2 --- Inhibits ASF/SF2 Phosphorylation by SRPK --- p.66 / Chapter 3.3 --- Surface Plasmon Resonance Binding Competition Assay --- p.76 / Chapter 3.4 --- Inhibitors Alters HIV-1 Alternative Splicing ex Vivo --- p.79 / Chapter 3.5 --- Cytotoxic effect of candidate compound on HeLa cells --- p.84 / Chapter 3.6 --- Nature compound alters ASF/SF2 localization --- p.86 / Chapter Chapter IV --- : Discussion and Conclusion --- p.89 / References --- p.95
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CD4? T-cell deficiency and dysfunction in HIV patients receiving combination antiretroviral therapyFernandez, Sonia January 2007 (has links)
[Truncated abstract] Failure to fully reconstitute the immune system is a common clinical problem in HIV patients who were severely immunodeficient before responding to combination antiretroviral therapy (CART). This can manifest as a deficiency in the number or function of CD4+ T-cells and occurs most often in patients who had a nadir CD4+ T-cell count below 100/μl when CART was commenced. Observational studies of large cohorts of HIV patients, such as the D:A:D study, have demonstrated that patients with low CD4+ T-cell counts have increased rates of death compared with patients who have normal CD4+ T-cell counts. Furthermore, individual case studies suggest that impaired recovery of pathogen-specific immune responses during CART is associated with opportunistic infections or disease progression. This thesis addresses possible causes of deficiencies in CD4+ T-cell number or function in HIV patients who were very immunodeficient prior to treatment and are responding (virologically) to CART. Firstly, the role of the thymus in producing naive CD4+ T-cells and the effects of persistent immune activation on the recovery of CD4+ T-cell numbers were assessed in patients with either low or high CD4+ T-cell counts after long-term CART. ... Proportions of antigen presenting cell (APC) subpopulations were examined in HIV patients with low or high CMV-specific CD4+ T-cell responses after long-term CART. HIV patients had significantly lower proportions of plasmacytoid dendritic cells (pDC) than HIV-negative controls. Furthermore, the proportions of pDC were positively correlated with CMV-specific CD4+ T-cell responses in HIV patients. Proportions of myeloid dendritic cells (mDC) were significantly higher in HIV patients than controls, and were also increased in patients with low CMV-specific CD4+ T-cell responses. Proportions of M-DC8+ dendritic cells or CD14+ monocytes did not differ between patients and controls, nor were they associated with CMV-specific CD4+ T-cell responses. Quantitation of cytokine (interferon-α, tumour necrosis factor-α, interleukin (IL) -12, IL-23, IL-15, IL-18 and IL-10) mRNA in unstimulated, purified populations of the APC described above revealed few significant differences between patients with low or high CD4+ T-cell IFN-γ responses to CMV. The only notable difference was the slight elevation of IL-15 mRNA levels in patients compared to controls. Since patients in the high responder group had the highest levels of IL-15 mRNA, this association may reflect the anti-apoptotic properties of IL-15. These studies provide valuable insights into the causes of persistent CD4+ T-cell deficiency and dysfunction in HIV patients on CART and may lead to better monitoring and treatments.
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