scholarly journals HTLV-1 AND TUBERCULOSIS ASSOCIATION: A REVIEW OF THE LITERATURE

Author(s):  
Normeide Pedreira dos Santos ◽  
Monique Lírio ◽  
Rita Elizabeth Moreira Mascarenhas ◽  
Leonardo Pereira Santana ◽  
Bernardo Galvão Castro ◽  
...  

Objective: To review and evaluate the scientific evidences on the relationship between tuberculosis (TB) and HTLV-1 infection. Methods: Searches on MEDLINE, LILACS/SciELO and Cochrane Library databases were performed using the following keywords: HTLV-1 Infection, Human T-lymphotropic virus type 1; Paraparesis Tropical Spastic; Tuberculosis. The following data were evaluated: Study design, sample size, number of controls, frequency of HTLV-1 infection in patients with TB and uninfected controls, mortality in HTLV-1/TB coinfected individuals compared with controls group, response in vivo and in vitro to PPD, frequency of individuals with tuberculin skin test (TST) positive or negative. Results: Nineteen articles were selected: twelve investigated prevalence, four mortality, three evaluated both prevalence and mortality and six described immunological findings. The majority of the studies was conducted in South America (Brazil and Peru), and Japan. Seven out of 12 studies found an increased risk of HTLV-1 in patients with TB diagnosis. The prevalence of HTLV-1/TB co-infection ranged from1.49 % in Brazil to 11.4 % in patients in Peru. Two out of five studies found a higher mortality of patients with HTLV-1/TB co-infection compared to patients with TB alone. Three studies conducted in Africa (Guinea Bissau and Senegal) found no increase in the mortality of patients co-infected with TB and HTLV-1. A decreased response to PPD in vitro or in vivo was observed in co-infected individuals compared with patients with TB alone. Conclusion: Patients with TB diagnosis have a higher prevalence of HTLV-1, compared with uninfected controls. Co-infection HTLV-1/TB increases the mortality of TB.

2010 ◽  
Vol 84 (24) ◽  
pp. 12801-12809 ◽  
Author(s):  
Won-Kyung Cho ◽  
Moon Kyoo Jang ◽  
Keven Huang ◽  
Cynthia A. Pise-Masison ◽  
John N. Brady

ABSTRACT Positive transcription elongation factor b (P-TEFb) plays an important role in stimulating RNA polymerase II elongation for viral and cellular gene expression. P-TEFb is found in cells in either an active, low-molecular-weight (LMW) form or an inactive, high-molecular-weight (HMW) form. We report here that human T-lymphotropic virus type 1 (HTLV-1) Tax interacts with the cyclin T1 subunit of P-TEFb, forming a distinct Tax/P-TEFb LMW complex. We demonstrate that Tax can play a role in regulating the amount of HMW complex present in the cell by decreasing the binding of 7SK snRNP/HEXIM1 to P-TEFb. This is seen both in vitro using purified Tax protein and in vivo in cells transduced with Tax expression constructs. Further, we find that a peptide of cyclin T1 spanning the Tax binding domain inhibits the ability of Tax to disrupt HMW P-TEFb complexes. These results suggest that the direct interaction of Tax with cyclin T1 can dissociate P-TEFb from the P-TEFb/7SK snRNP/HEXIM1 complex for activation of the viral long terminal repeat (LTR). We also show that Tax competes with Brd4 for P-TEFb binding. Chromatin immunoprecipitation (ChIP) assays demonstrated that Brd4 and P-TEFb are associated with the basal HTLV-1 LTR, while Tax and P-TEFb are associated with the activated template. Furthermore, the knockdown of Brd4 by small interfering RNA (siRNA) activates the HTLV-1 LTR promoter, which results in an increase in viral expression and production. Our studies have identified Tax as a regulator of P-TEFb that is capable of affecting the balance between its association with the large inactive complex and the small active complex.


2000 ◽  
Vol 74 (3) ◽  
pp. 1094-1100 ◽  
Author(s):  
Joshua T. Bartoe ◽  
Björn Albrecht ◽  
Nathaniel D. Collins ◽  
Michael D. Robek ◽  
Lee Ratner ◽  
...  

ABSTRACT Human T-lymphotropic virus type 1 (HTLV-1) causes adult T-cell leukemia/lymphoma and is associated with a variety of immune-mediated disorders. The role of four open reading frames (ORFs), located between env and the 3′ long terminal repeat of HTLV-1, in mediating disease is not entirely clear. By differential splicing, ORF II encodes two proteins, p13II and p30II, both of which have not been functionally defined. p13II localizes to mitochondria and may alter the configuration of the tubular network of this cellular organelle. p30II localizes to the nucleolus and shares homology with the transcription factors Oct-1 and -2, Pit-1, and POU-M1. Both p13II and p30II are dispensable for infection and immortalization of primary human and rabbit lymphocytes in vitro. To test the role of ORF II gene products in vivo, we inoculated rabbits with lethally irradiated cell lines expressing the wild-type molecular clone of HTLV-1 (ACH.1) or a clone containing selected mutations in ORF II (ACH.30/13.1). ACH.1-inoculated animals maintained higher HTLV-1-specific antibody titers than animals inoculated with ACH.30/13.1. Viral p19 antigen was transiently detected in ex vivo cultures of peripheral blood mononuclear cells (PBMC) from only two ACH.30/13.1-inoculated rabbits, while PBMC cultures from all ACH.1-inoculated rabbits routinely produced p19 antigen. In only three of six animals exposed to the ACH.p30II/p13IIclone could provirus be consistently PCR amplified from extracted PBMC DNA and quantitative competitive PCR showed the proviral loads in PBMC from ACH.p30II/p13II-infected rabbits to be dramatically lower than the proviral loads in rabbits exposed to ACH. Our data indicate selected mutations in pX ORF II diminish the ability of HTLV-1 to maintain high viral loads in vivo and suggest an important function for p13II and p30II in viral pathogenesis.


2006 ◽  
Vol 80 (10) ◽  
pp. 4781-4791 ◽  
Author(s):  
Meisheng Zhou ◽  
Hanxin Lu ◽  
Hyeon Park ◽  
Jaime Wilson-Chiru ◽  
Rebecca Linton ◽  
...  

ABSTRACT Human T-lymphotropic virus type 1 (HTLV-1) encodes a transcriptional activator, Tax, whose function is essential for viral transcription and replication. Tax transactivates the viral long-terminal repeat through a series of protein-protein interactions which facilitate CREB and CBP/p300 binding. In addition, Tax dissociates transcription repressor histone deacetylase 1 interaction with the CREB response element. The subsequent events through which Tax interacts and communicates with RNA polymerase II and cyclin-dependent kinases (CDKs) are not clearly understood. Here we present evidence that Tax recruits positive transcription elongation factor b (P-TEFb) (CDK9/cyclin T1) to the viral promoter. This recruitment likely involves protein-protein interactions since Tax associates with P-TEFb in vitro as demonstrated by glutathione S-transferase fusion protein pull-down assays and in vivo as shown by coimmunoprecipitation assays. Functionally, small interfering RNA directed toward CDK9 inhibited Tax transactivation in transient assays. Consistent with these findings, the depletion of CDK9 from nuclear extracts inhibited Tax transactivation in vitro. Reconstitution of the reaction with wild-type P-TEFb, but not a kinase-dead mutant, recovered HTLV-1 transcription. Moreover, the addition of the CDK9 inhibitor flavopiridol blocked Tax transactivation in vitro and in vivo. Interestingly, we found that Tax regulates CDK9 kinase activity through a novel autophosphorylation pathway.


1983 ◽  
Vol 50 (02) ◽  
pp. 576-580 ◽  
Author(s):  
M A Boogaerts ◽  
D E Hammerschmidt ◽  
C Roelant ◽  
R L Verwilghen ◽  
H S Jacob

SummaryImmune triggered granulocyte (PMN)-endothelial interactions have been implicated in the pathogenesis of vascular diseases. While hyperuricemia and gout are associated with an increased risk of atherogenesis, we studied the modulation by mono- sodiumurate (MSU) crystals of PMN-endothelial interactions in vitro. The relationship between calciumoxalate (COX) crystals - implicated in the vasculitis of primary oxalosis - and immunologically mediated endothelial injury was also explored.Both MSU- and COX-crystals activate complement (C), as illustrated by the finding of strong PMN aggregating activity and large amounts of C3a and C5a-anaphylatoxin in MSU- and COX- crystal incubated sera.MSU- and COX-crystal treated sera stimulate PMN to adhere to and induce significant 51Cr-release from endothelial cells in vitro. Platelets significantly increase crystal-triggered PMN endothelial cell adherence and 51Cr-release. This platelet augmenting effect depends on the release of platelet constituents (e. g. serotonin).Microcrystalline material present in vessel walls, thus may cause C-activation and may trigger PMN and platelets to damage endothelium in vitro and in vivo. These findings may have relevance to the understanding of the accelerated atherogenesis of hyperuricemia and the fulminant vasculitis of oxalosis or ethylene glycol poisoning.


Author(s):  
M.J. Murphy ◽  
R.R. Price ◽  
J.C. Sloman

The in vitro human tumor cloning assay originally described by Salmon and Hamburger has been applied recently to the investigation of differential anti-tumor drug sensitivities over a broad range of human neoplasms. A major problem in the acceptance of this technique has been the question of the relationship between the cultured cells and the original patient tumor, i.e., whether the colonies that develop derive from the neoplasm or from some other cell type within the initial cell population. A study of the ultrastructural morphology of the cultured cells vs. patient tumor has therefore been undertaken to resolve this question. Direct correlation was assured by division of a common tumor mass at surgical resection, one biopsy being fixed for TEM studies, the second being rapidly transported to the laboratory for culture.


Author(s):  
Hyoung-Jin Moon ◽  
Won Lee ◽  
Ji-Soo Kim ◽  
Eun-Jung Yang ◽  
Hema Sundaram

Abstract Background Aspiration testing before filler injection is controversial. Some believe that aspiration can help prevent inadvertent intravascular injection, while others cite false-negative results and question its value given that the needle position always changes somewhat during injection procedures. Objectives To test the relation of false-negative results to the viscosity of the material within the needle lumen and determine whether a less viscous material within the needle lumen could decrease the incidence of false-negative results. Methods In vitro aspiration tests were performed using 30-G and 27-G needle gauges, two cross-linked hyaluronic acid fillers, normal saline bags pressurized at 140 and 10 mmHg to mimic human arterial and venous pressures, and three needle lumen conditions (normal saline, air, and filler). Testing was repeated three times under each study condition (72 tests in total). For in vivo correlation, aspiration tests were performed on femoral arteries and central auricular veins in three rabbits (4–5 aspirations per site, 48 tests in total). Results In vitro and in vivo testing using 30-G needles containing filler both showed false-negative results on aspiration testing. In vitro and in vivo testing using needles containing saline or air showed positive findings. Conclusions False-negative results from aspiration testing may be reduced by pre-filling the needle lumen with saline rather than a filler. The pressurized system may help overcome challenges of animal models with intravascular pressures significantly different from those of humans. The adaptability of this system to mimic various vessel pressures may facilitate physiologically relevant studies of vascular complications.


2021 ◽  
Vol 7 (1) ◽  
Author(s):  
Yi Xin She ◽  
Qing Yang Yu ◽  
Xiao Xiao Tang

AbstractInterleukins, a group of cytokines participating in inflammation and immune response, are proved to be involved in the formation and development of pulmonary fibrosis. In this article, we reviewed the relationship between interleukins and pulmonary fibrosis from the clinical, animal, as well as cellular levels, and discussed the underlying mechanisms in vivo and in vitro. Despite the effects of interleukin-targeted treatment on experimental pulmonary fibrosis, clinical applications are lacking and unsatisfactory. We conclude that intervening in one type of interleukins with similar functions in IPF may not be enough to stop the development of fibrosis as it involves a complex network of regulation mechanisms. Intervening interleukins combined with other existing therapy or targeting interleukins affecting multiple cells/with different functions at the same time may be one of the future directions. Furthermore, the intervention time is critical as some interleukins play different roles at different stages. Further elucidation on these aspects would provide new perspectives on both the pathogenesis mechanism, as well as the therapeutic strategy and drug development.


2021 ◽  
Vol 22 (12) ◽  
pp. 6196
Author(s):  
Anna Pieniazek ◽  
Joanna Bernasinska-Slomczewska ◽  
Lukasz Gwozdzinski

The presence of toxins is believed to be a major factor in the development of uremia in patients with chronic kidney disease (CKD) and end-stage renal disease (ESRD). Uremic toxins have been divided into 3 groups: small substances dissolved in water, medium molecules: peptides and low molecular weight proteins, and protein-bound toxins. One of the earliest known toxins is urea, the concentration of which was considered negligible in CKD patients. However, subsequent studies have shown that it can lead to increased production of reactive oxygen species (ROS), and induce insulin resistance in vitro and in vivo, as well as cause carbamylation of proteins, peptides, and amino acids. Other uremic toxins and their participation in the damage caused by oxidative stress to biological material are also presented. Macromolecules and molecules modified as a result of carbamylation, oxidative stress, and their adducts with uremic toxins, may lead to cardiovascular diseases, and increased risk of mortality in patients with CKD.


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