Mutation of the herpes simplex virus 1 KOS UL45 gene reveals dose dependent effects on central nervous system growth

Summary.  The herpes simplex virus type 1 (HSV-1) UL45 gene encodes an 18 kDa virion envelope protein whose function remains unknown. Previous studies using a UL45 null mutant, UL45Δ, demonstrated that deletion of the UL45 gene altered plaque size in Vero and HeLa cells, but was not essential for replication in these cell types. The goal of this study was to determine if mutation of the UL45 gene influenced virus growth in the CNS. Two UL45 mutants, as well as a repaired revertant virus, were constructed and tested for their ability to cause encephalitis and replicate in the CNS. The UL45 mutants were not lethal when 1 × 10³ pfu were injected intracerebrally into Balb/c mice. In contrast, at inocula greater than 1 × 10³, the UL45 mutants were lethal. In vivo growth curves derived from mice inoculated intracerebrally with 1 × 10³ pfu of virus revealed that the mutants grew poorly compared to wild type or revertant viruses. These results suggest that the 18 kDa UL45 gene product is required for efficient growth in the central nervous system at low doses. We propose that the UL45 gene may play an important role under the conditions of a naturally acquired infection. Received June 23, 2001 Accepted November 1, 2001     

In vitro sensitivity of Blastocystis hominis to garlic, ginger, white cumin, and black pepper used in diet

To determine the growth pattern and in vitro susceptibility of Blastocystis hominis to metronidazole (MTZ), garlic, ginger, white cumin, and black pepper. Stool specimens were collected from 16 irritable bowel syndrome (IBS) and 10 controls between July–November 2010. Stool microscopy and culture for B. hominis was performed. Drug susceptibility assays was done using 0.01 and 0.1 mg/ml of MTZ, garlic, ginger, white cumin, and black pepper. Effect was assessed on B. hominis culture after 48 h. Stool DNA was extracted using stool DNA extraction kit (Qiagen) and polymerase chain reaction (PCR) done using subtype-specific sequence-tagged-site primers. B. hominis genotype 3 and coinfection of 1 and 3 tended to grow well in culture compared to isolated type 1 infection. Exposed to MTZ at a concentration of 0.01 mg/ml, 38% (6/16) B. hominis from IBS did not grow in culture compared to 100% (10/10) of B. hominis from control (p = 0.001). When they were exposed to MTZ at 0.1 mg/ml, 56% (9/16) B. hominis from IBS did not grow in cultures compared to 100% (10/10) from control (p = 0.01). Forty-four percent (7/16) B. hominis from IBS did not grow in culture compared to 100% (10/10) B. hominis from control when exposed to garlic at a concentration of 0.01 mg/ml (p = 0.003) and following exposure to garlic at 0.1 mg/ml, 38% (6/16) B. hominis from IBS did not grow in cultures compared to 100% (10/10) from control (p = 0.001). B. hominis isolates from IBS had a cell count of 6,625 at a MTZ concentration of 0.01 mg/ml that reduced to 1,250 as MTZ concentration was increased to 0.1 mg/ml (p = 0.08). B. hominis from IBS with a mean cell count of 3 × 10⁵ at baseline decreased to 1 × 10⁴ when exposed to garlic at 0.01 mg/ml (p < 0.001) and to 1 × 10³ (p < 0.001) when garlic was 0.1 mg/ml. B. hominis from IBS cell count decreased to 1 × 10⁵ when exposed to white cumin at 0.01 mg/ml (p = 0.01) and to 1 × 10⁵ (p < 0.001) when white cumin was 0.1 mg/ml. Exposed to black pepper at 0.1 mg/ml, cell count of B. hominis from IBS decreased to 1 × 10⁵ (p = 0.01). B. hominis from IBS decreased to 1.3 × 10⁵ exposed to ginger at 0.01 mg/ml (p = 0.001). B. hominis isolates were mostly genotypes 3, type 1 and 3 coinfection, and non-typeable B. hominis isolates. B. hominis isolates from IBS mostly genotype 1 demonstrated an increased sensitivity to garlic at 0.01 mg/ml with a B. hominis cell count of 3,714 compared to 6,142 when exposed to 0.01 mg/ml of MTZ. However, this sensitivity did not increase as garlic concentration was increased to 0.1 mg/ml, for B. hominis cell count was 6,000 compared to 1,428 as MTZ was increased to 0.1 mg/ml.     

Dynamics of the Formation of Rhythmic Activity of the Heart in Fetuses and Newborn Rats

The development of heart activity and its relationship with respiratory and motor activities were studied in rat fetuses with preserved placental circulation on gestation days 15-20 (E15-20) and in newborn rats (P0). During the studied period, the heart rate in fetuses increased from 175.93 ± 6.10 bpm (E15) to 271.82 ± 5.93 bpm (E20). After birth, the heart rate decreased to 220.94 ± 8.73 bpm. Heart rate variability in the decasecond and near-minute ranges was detected. At E16 stage it is presented by slow regular oscillations lasting for 20-35 sec with an amplitude of 10-45 msec. Comparison of functional activities of the cardiac and somatic motor systems showed that at E16, fl uctuations in heart rate are independent of the bouts of motor excitation. During growing, the degree of synchronization of heart rate variability with physical activity increased. E17-18 stage is characterized by short-term episodes of heart rate deceleration associated with motor activity; their duration and amplitude did not depend much on the force of movement. At E19-20, decelerations typical of early gestation terms were replaced by acceleration-type reactions typical for mature organism, which is related to maturation of coordination function of the nervous system. In the heart rhythm, respiratory arrhythmia appears during episodes of rhythmic breathing. Newborn rats demonstrated acceleration episodes; their parameters depend on the force of motor bouts; respiratory arrhythmia was not observed.     

Cytologic and morphologic characteristics of human papillomavirus infection in cervix uteri pathology]

The role of human papilloma virus (HPV) in genital cancer is not yet clear at present, but the available data testify to serious changes in cervix uteri epithelium in the process of its infection. Close correlation was demonstrated between HPV type specificity and the degree of epithelial morphological changes as well as histologic tumor variant, and its degree of differentiation. Interrelation between HPV type and level of both regression and progression of atypically changed cervix uteri epithelium is established. Cytomorphological method of the evaluation of cell koilocytotic atypia is the marker to diagnose HPV infection when screening a chosen woman population. The development and introducing of sensitive and reliable identification methods of type-specific DNA sequences of HPV infection in diagnostic material to form a low risk (HPV-6 and II types) and a high risk group (HPV-16 and 18 types) by malignancy of cervix uteri epithelium have considerable promise. It is advisable to study HPV role in the development of adenogenic tumors of uterine cervix and body.     

Interleukin-18 Binding Protein in the Sera of Patients with Wegener’s Granulomatosis

Introduction  In the present study, we examined the levels of the pro-inflammatory cytokine IL-18 and its natural inhibitor, the IL-18 binding protein (IL-18BP), in sera of Wegener’s granulomatosis (WG) patients at various stages of the disease. Patients and Methods  Sera from eight consecutive biopsy-proven systemic WG patients (four men and four women; age at diagnosis 58.4 ± 13.8 years) were obtained longitudinally with a follow-up period of 55.2 ± 30 months. Sera obtained from 50 healthy subjects were used as controls. Results and Discussion  Serum levels of IL-18, IL-18BP, and free IL-18 obtained during an active phase of the disease (Birmingham Vasculitis Activity Score, BVAS > 10) were more than twofold higher than levels in the same patients during inactive disease stages (BVAS < 5; P < 0.002; P < 0.006, and P < 0.03 for IL-18, IL-18BP, and free IL-18, respectively). During inactive stages, the levels of these markers were comparable to those of healthy controls. The elevated levels of IL-18 and IL-18BP in sera during active stages of disease suggest a possible role in the pathogenesis and course of the WG. Conclusion  Despite the elevated IL-18BP levels during active disease, free IL-18 remained higher than in the inactive disease stages, suggesting a potential benefit of administration of exogenous IL-18BP as a novel therapeutic approach for active WG.     

Influence of Image Metrics When Assessing Image Quality from a Test Object in Cardiac X-ray Systems

Modern fluoroscopic systems used for invasive cardiology typically acquire digital images in a 1,024 × 1,024 × 12 bits. These images are maintained in the original format while they remain on the imaging system itself. However, images are usually stored using a reduced 512 × 512 × 8-bits format. This paper presents a method for digital analysis of test objects images. The results obtained using image-intensifier and flat-detector systems are given for the original and reduced matrices. Images were acquired using a test object (TO) and a range of polymethyl methacrylate (PMMA) thicknesses from 4 to 28 cm. Adult patient protocols were evaluated for 16–28 cm of PMMA using the image-intensifier system. Pediatric protocols were evaluated for 4–16 cm of PMMA using the flat-detector system. The TO contains disks of various thicknesses to evaluate low contrast sensitivity and a bar pattern to evaluate high-contrast spatial resolution (HCSR). All available fluoroscopic and cine modes were evaluated. Entrance surface air kerma was also measured. Signal-to-noise ratio (SNR) was evaluated using regions of interest (ROI). HCSR was evaluated by comparing the statistical analysis of a ROI placed over the image of the bar pattern against a reference ROI. For both systems, an improvement of approximately 20% was observed for the SNR on the reduced matrices. However, the HCSR parameter was substantially lower in the reduced metrics. Cardiologists should consider the clinical influence of reduced spatial resolution when using the archived images.     

Demonstration of multiple HPV types in normal cervix and in cervical squamous cell carcinoma using the polymerase chain reaction on paraffin wax embedded material.

The prevalence of human papilloma virus (HPV) types 6, 11, 16 and 18 was investigated using the polymerase chain reaction on formalin fixed, paraffin wax embedded material in 19 cases of cervical squamous cell carcinoma and in 10 normal cervices. HPV DNA was detected in 16 of 19 carcinomas, with multiple types present in 11 of these. HPV 16 or 18, or both, were present in all cases in which HPV was shown. Six of 10 cases of normal cervix contained HPV; five of these contained two or more HPV types, including HPV 16 or 18, or both. This study shows the feasibility of using the PCR on paraffin wax embedded material and indicates a high rate of carriage of multiple HPV types in both normal and neoplastic cervix.     

Prevalence,viral load,and physical status of HPV 16 and 18 in cervical adenosquamous carcinoma

Adenosquamous carcinoma of the uterine cervix is a rare mixture of malignant squamous and glandular epithelial elements and accounts for approximately 10% of cervical carcinomas. The aims of the present study were to evaluate the prevalence, physical status, and viral load of HPV 16 and 18 in adenosquamous carcinoma. Formalin-fixed paraffin-embedded tissue samples from 20 cases of histologically diagnosed adenosquamous carcinoma were examined. The squamous and glandular components were separately microdissected and analyzed for their HPV DNA subtype, viral load, and physical status using real-time polymerase chain reaction (PCR). The percentages of HPV 16- and 18-positive cases among all the HPV-positive cases were 36.8% (7/19) and 57.9% (11/19) in the squamous epithelial elements and 33.3% (6/18) and 61.1% (11/18) in the glandular elements, respectively. PCR analysis with E2 primers revealed that seven of eleven (63.6%) HPV 18-positive cases had the pure integrated form in both elements. The mean HPV 16 DNA copy numbers/cell was 7.22 in the squamous elements and 1.33 in the glandular elements (p = 0.04) while the corresponding mean HPV 18 DNA copy numbers/cell was 1.50 and 0.89, respectively. The prevalence of HPV 18 in adenosquamous carcinoma was high and many HPV 18-positive cases were the pure integrated form resulting in very low copy numbers/cell. It is possible that more aggressive transformation with early integration of HPV 18 results in cases with greater chromosomal instabilities, higher growth rates, and rapid progression.     

<Emphasis Type="Italic">S</Emphasis>-Methylisothiourea Induces Apoptosis of Herpes Simplex Virus-1-Infected Microglial Cells

Our study showed that S-methylisothiourea (SMT) had anti-inflammatory effects in treating herpes simplex encephalitis in mice, and SMT also induced apoptosis of herpes simplex virus (HSV-1)-infected microglial cells. Both animal and cell models were employed in this study. Both models included the following five groups: a normal control group, a virus group (HSV-1 infected), an SMT group (HSV-1-infected + SMT (0.1 mg/10 g)), a dexamethasone group (HSV-1 infected + dexamethasone (2 μg/10 g)), and an APS group (HSV-1-infected + APS (0.8 mg/10 g)). ELISA was used to measure tumor necrosis factor (TNF)-α, interleukin (IL)-1β, and IL-10, and Greiss method was used for measuring nitric oxide (NO) secretion. HE staining was performed for detecting changes in mice brain. Flow cytometry assay for caspase-3, caspase-8, caspase-9, and caspase-12 expressions was also carried out to assess apoptosis. Expressions of TNF-α, IL-1β, and NO were significantly elevated after stimulation of microglial cells with HSV-1. Following SMT intervention, TNF-α, IL-1β, and NO levels were significantly decreased. The inflammatory changes in HSV-1-infected murine brain tissues were also reduced. SMT induction of apoptosis of HSV-stimulated microglia seemed to be through three pathways: the death receptor, mitochondrially gated, and endoplasmic reticulum. SMT can reduce HSV-induced inflammatory insult to the brain. Its mechanism of action is most probably due to the induction of microglial cell apoptosis.     

Diagnostic value of procalcitonin in pleural effusions

This study was to determine the diagnostic value of procalcitonin (PCT) in the differentiation of infectious and non-infectious causes of pleural effusion. From January 2005 to April 2005, we measured the PCT levels of pleural effusion from 76 patients using an immunoluminometric assay. The types of pleural infusions studied were para-pneumonic effusion (n = 26), empyema (n = 7), tuberculous pleurisy (n = 8), malignant pleural effusion (n = 25) and transudative pleural effusion (n = 8). The PCT levels were low in transudative pleural effusions (0.188 ± 0.077 ng/mL) and tuberculous pleurisy (0.130 ± 0.069 ng/mL), but high in empyema (5.147 ± 3.056 ng/mL), para-pneumonic effusion (1.091 ± 0.355 ng/mL), and malignant pleural effusion (0.241 ± 0.071 ng/mL). The receiver-operating characteristic curve analysis for an optimal discrimination between empyema and para-pneumonic effusion from non-para-pneumonic effusion could be performed at a cut-off point of 0.18 ng/mL with area under the curve of 0.776 (sensitivity: 69.7%, specificity: 72.1%). The correlation was found between pleural effusion PCT and serum PCT levels in 16 patients (r ² = 0.967, p < 0.001). In conclusion, a high pleural effusion PCT level suggests the presence of empyema and para-pneumonic effusion.     

Six-stage cascade paramagnetic mode magnetophoretic separation system for human blood samples

This paper is focused on the development of a six-stage cascade paramagnetic mode magnetophoretic separation (PMMS) system for separating suspended cells in blood based on their native magnetic properties. The design and fabrication of a PMMS system are presented and the microfluidic separation system is characterized experimentally using human whole blood as the case study. The PMMS system can separate blood cells types continuously using the magnetophoretic force produced from a high magnetic field gradient without magnetic or fluorescent tagging. Experimental results demonstrated that red blood cell separation in the PMMS system at a volumetric flow rate of 28.8 μL / hr, resulting in a separation time of 10.4 min for a 5.0 μL blood sample with a separation efficiency of 89.5 ± 0.20%. The PMMS system was tested at higher volumetric flow rates of 50.4 μL / hr and 72.0 μL / hr. The measured separation efficiencies were 86.2 ± 1.60% and 59.9 ± 6.06% respectively.     

Real-time PCR strategy and detection of bacterial agents of lymphadenitis

The aim of this study was to compare 16 S rRNA gene amplification and sequencing with a systematic real-time PCR assay screening strategy that includes all common known pathogens recovered from lymph node biopsy specimens. Lymph node biopsy samples sent to our laboratory from January 2007 to December 2008 were tested in the study. Lymph nodes were screened for the presence of any bacteria by PCR amplification and sequencing targeting the 16 S rRNA gene and also by a specific real-time PCR strategy that includes Bartonella henselae, mycobacteria, Francisella tularensis, and Tropheryma whipplei. By testing 491 lymph nodes, we found that the sensitivity of our specific real-time PCR assay strategy was significantly higher than 16 S rRNA PCR amplification and sequencing for the detection of Bartonella henselae (142 vs 98; p < 10⁻⁴), Francisella tularensis (16 vs 10, p < 10⁻⁴), and mycobacteria (8 versus 3, p < 10⁻⁴). None of the samples was positive for Tropheryma whipplei. Our study demonstrates the usefulness and specificity of a systematic real-time PCR strategy for molecular analysis of lymph node biopsy specimens and the higher sensitivity compared with standard 16 S rRNA gene amplification and sequencing.     

Evidence for a segmented genome and partial nucleotide sequences of maize yellow stripe virus,a proposed new tenuivirus

Summary Attempts at molecular characterization of a maize yellow stripe virus (MYSV) isolate from Egypt revealed that it has a tenuivirus-like segmented genome consisting of five RNA segments (>9.5, 2.4, 2.1, 1.6 and 1.6 kb). Whereas the complete sequence of RNA-5 consists of 1562 nts, only 1152, 1085, 1213, and 808 nts of RNA-1, -2, -3, and -4, respectively, were determined from the MYSV genome, estimated to be 18 kb. Four of the MYSV segments had complementary and conserved 5′ and 3′ termini similar to those of tenuiviruses and phleboviruses. No cross hybridization was observed between MYSV and maize stripe virus (MSpV), a definite member of the genus Tenuivirus. Also, no nucleotide or peptide sequence similarities were detected between the five sequenced stretches of the MYSV genome and any virus sequences, including those of tenuiviruses, available in the databases.     

Cardiac dimensions, physical activity, and submaximal working capacity in youth of the Québec Family Study

The relationships between cardiac dimensions and physical activity and submaximal working capacity were examined in 198 boys and 154 girls, aged 9–18 years, who were participants in the first phase of the Québec Family Study. The sample was divided into three age groups, 9–12 years, 13–15 years, and 16–18 years. Indicators of physical activity included estimated daily energy expenditure (EE) and time spent in moderate-to-vigorous physical activity (median metabolic equivalents of energy expenditure above resting metabolic rate ≥4.8). Submaximal physical working capacity (PWC₁₅₀) was determined using a submaximal exercise test on a Monark cycle ergometer. Echocardiographically determined dimensions included posterior wall thickness, septal wall thickness, and left ventricular mass (LVM). The analyses were based on partial correlation and analysis of covariance, controlling for age and body surface area. Relationships between EE/physical activity variables and cardiac dimensions were low and, at best, moderate (r < 0.45). With subjects grouped into tertiles by indicators of physical activity, LVM was significantly different only among 16- to 18-year-old girls (157 g vs 134 g in the highest and lowest quartiles, respectively; P < 0.05). Correlations between cardiac dimensions and PWC₁₅₀ were also low (r < 0.30), with few significant relationships. In general, cardiac dimensions were not related to habitual physical activity and PWC₁₅₀ in young subjects aged 9–18 years. However, significant correlations were positive, as expected. LVM may be related to submaximal power output in boys since it accounts for 3% of the variance, after adjusting for age and BSA. Received: 4 January 1999 / Accepted: 8 June 1999     

Association of cytologic grade of anal “Pap” smears with viral loads of human papillomavirus types 16, 18, and 52 detected in the same specimens from men who have sex with men

BackgroundHuman papilloma virus (HPV) load has been linked to cellular abnormalities of the uterine cervix, and proposed as predictors of HPV persistence and progression of dysplasia to cervical cancer. However, the association of HPV viral load and anal dysplasia and cancer has not been as thoroughly investigated.ObjectivesTo examine the association of the viral loads of high-risk HPV types 16, 18, and 52, with the cytologic severity grading in anal-swab specimens of MSM with and without HIV-1 co-infection.Study designA cross-sectional study recruited 200 MSM in northern Thailand from July 2012 to January 2013. Real-time qPCR amplified portion of the HPV E6E7 gene, as well as the human β-globin gene to validate adequacy of the anal specimens and to normalize interpatient viral-load comparisons. Genotyping by linear-array assay identified and distinguished types 16, 18, and 52.ResultsHPV-16, and -18 viral loads increased with respect to the abnormality of the cytologic diagnoses (p < 0.05 for HPV-16, p < 0.01 for HPV-18). HIV-1 positivity was associated with higher HPV-18 viral load (p = 0.006). HPV-16 viral loads ≥10^2.24 copies per 5000 anal cells, and HPV-18 loads ≥10^3.15, were independently associated with abnormal cytology on logistic regression (p = 0.022, p = 0.041, respectively). Positive predictive values were 85.2% (23/27) and 80.0% (44/55) for the high viral load of a particular HPV-16 and the combined HPV-16, -18 and -52 types, respectively.ConclusionsHigh viral loads of HPV types 16 and 18 appear to be associated with anal cytologic abnormalities. The clinical utility of HPV viral loads to predict risk for anal cancer remains to be determined by a larger prospective cohort with sufficient frequency of high-grade dysplasia.     

Morphology of hepatitis C and hepatitis B virus particles as detected by immunogold electron microscopy

We performed indirect immunogold electron microscopy (EM) for immunological identification and characterization of hepatitis C virus (HCV). To clarify the morphology of HCV, an indirect immunogold EM of two plasma samples from patients with high HCV RNA titers was carried out using antibodies specific for the putative HCV envelope protein (E) 1. Spherical virus particles 55–65 nm in diameter with delicate spike projections were detected in the 1.14–1.16 g/ml fractions after sucrose density gradient centrifugation. Polyclonal and monoclonal antibodies to the putative HCV E1 specifically recognized these particles. In addition, immunogold EM of the samples was also performed to uncover the morphology of HCV core particles. Spherical particles 33–40 nm in diameter (average, 37 nm) were detected in the 1.22- to 1.25-g/ml fractions by conventional EM after sucrose density gradient centrifugation. Immunogold EM using rabbit polyclonal antibody (RR8) specific for the putative HCV core protein and colloidal gold-labeled goat antirabbit IgG showed binding of the gold particles with RR8. Some of the HCV core particles showed icosahedric morphology. Optical rotation technique showed that the HCV core particles exhibit sixfold symmetry and that the length of the regular hexagon side is approximately 20 nm, suggesting that they have an icosahedric structure. Further, the detection limit of the indirect immunogold EM was evaluated in 11 plasma samples from chronic hepatitis B patients with different degrees of hepatitis B virus (HBV) DNA titers using antihepatitis B surface antigen antibody. The study showed that the detection limit of virus using this method is 10⁷ virions/ml.     

Pulmonary <Emphasis Type="Italic">Mycobacterium simiae</Emphasis> infection: comparison with pulmonary tuberculosis

To identify the clinical and radiological features distinguishing Mycobacterium simiae respiratory infection from pulmonary tuberculosis, the demographics, underlying conditions, and clinical and radiological findings of 121 consecutive patients with pulmonary tuberculosis and 102 with M. simiae respiratory infection were compared retrospectively. In the M. simiae group, the patients were older (mean age 69 ± 16 years vs. 47 ± 21 years, p = 0.0001), with a female predominance (62% vs. 45%, p = 0.008). Only 4% were of Ethiopian origin compared to 25% of the tuberculosis group (p = 0.0001). M. simiae infection was associated with significantly higher rates of smoking history, underlying chronic obstructive pulmonary disease, zero human immunodeficiency virus (HIV) infection compared to 10% in the tuberculosis group (p = 0.001), blunted symptoms, and noncavitary infiltrates in the lower/middle lobes on chest X-ray. HIV-negative patients with M. simiae respiratory infection are distinguishable from patients with pulmonary tuberculosis by several demographic, clinical, and radiological features. These findings have important diagnostic and therapeutic implications.     

CD8+ Cell Anti-HIV Activity Rapidly Increases Upon Discontinuation of Early Antiretroviral Therapy

Introduction  CD8+ lymphocytes can suppress HIV replication without killing the infected cells. This CD8+ cell noncytotoxic anti-HIV response (CNAR) is associated with a beneficial clinical course. Materials and Methods  In this longitudinal study of 16 participants in the Options Project at UCSF, we measured the ability of CD8+ lymphocytes to suppress HIV replication in CD4+ cells during primary HIV infection, early antiretroviral therapy, and after treatment. Results and Discussion  CD8+ lymphocytes from subjects with untreated primary HIV-1 infection strongly suppressed HIV replication. Initiation of antiretroviral therapy during primary HIV-1 infection caused a marked decline in this CNAR. CD8+ cells from these subjects regained anti-HIV activity when early therapy was discontinued. The timing of the appearance of CD8+ cell anti-HIV activity directly correlated with the emergence of detectable virus levels. Maximal CNAR activity coincided with a decay in the kinetics of HIV replication. In addition, peak viral loads during treatment interruption were lower than pre-treatment virus levels (median reduction = 0.8 logs, p = 0.005) and CD4+ T cell counts were maintained for a 24-week period of follow-up. Conclusion  These results suggest that CNAR plays an important role in suppressing HIV replication in the setting of antiretroviral treatment interruption in HIV-infected individuals.