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Dive into the research topics where James L. K. Fletcher is active.

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Featured researches published by James L. K. Fletcher.


Retrovirology | 2013

A novel acute HIV infection staging system based on 4th generation immunoassay.

Jintanat Ananworanich; James L. K. Fletcher; Suteeraporn Pinyakorn; Frits van Griensven; Claire Vandergeeten; Alexandra Schuetz; Tippawan Pankam; Rapee Trichavaroj; Siriwat Akapirat; Nitiya Chomchey; Praphan Phanuphak; Nicolas Chomont; Nelson L. Michael; Jerome H. Kim; Mark S. de Souza

BackgroundFourth generation (4thG) immunoassay (IA) is becoming the standard HIV screening method but was not available when the Fiebig acute HIV infection (AHI) staging system was proposed. Here we evaluated AHI staging based on a 4thG IA (4thG staging).FindingsScreening for AHI was performed in real-time by pooled nucleic acid testing (NAT, n=48,828 samples) and sequential enzyme immunoassay (EIA, n=3,939 samples) identifying 63 subjects with non-reactive 2nd generation EIA (Fiebig stages I (n=25), II (n=7), III (n=29), IV (n=2)). The majority of samples tested (n=53) were subtype CRF_01AE (77%). NAT+ subjects were re-staged into three 4thG stages: stage 1 (n=20; 4th gen EIA-, 3rd gen EIA-), stage 2 (n=12; 4th gen EIA+, 3rd gen EIA-), stage 3 (n=31; 4th gen EIA+, 3rd gen EIA+, Western blot-/indeterminate). 4thG staging distinguishes groups of AHI subjects by time since presumed HIV exposure, pattern of CD8+ T, B and natural killer cell absolute numbers, and HIV RNA and DNA levels. This staging system further stratified Fiebig I subjects: 18 subjects in 4thG stage 1 had lower HIV RNA and DNA levels than 7 subjects in 4thG stage 2.ConclusionsUsing 4th generation IA as part of AHI staging distinguishes groups of patients by time since exposure to HIV, lymphocyte numbers and HIV viral burden. It identifies two groups of Fiebig stage I subjects who display different levels of HIV RNA and DNA, which may have implication for HIV cure. 4th generation IA should be incorporated into AHI staging systems.


EBioMedicine | 2016

HIV DNA Set Point is Rapidly Established in Acute HIV Infection and Dramatically Reduced by Early ART

Jintanat Ananworanich; Nicolas Chomont; Leigh Ann Eller; Eugene Kroon; Sodsai Tovanabutra; Meera Bose; Martin Nau; James L. K. Fletcher; Somporn Tipsuk; Claire Vandergeeten; Robert J. O'Connell; Suteeraporn Pinyakorn; Nelson L. Michael; Nittaya Phanuphak; Merlin L. Robb

HIV DNA is a marker of HIV persistence that predicts HIV progression and remission, but its kinetics in early acute HIV infection (AHI) is poorly understood. We longitudinally measured the frequency of peripheral blood mononuclear cells harboring total and integrated HIV DNA in 19 untreated and 71 treated AHI participants, for whom 50 were in the earliest Fiebig I/II (HIV IgM −) stage, that is ≤ 2 weeks from infection. Without antiretroviral therapy (ART), HIV DNA peaked at 2 weeks after enrollment, reaching a set-point 2 weeks later with little change thereafter. There was a marked divergence of HIV DNA values between the untreated and treated groups that occurred within the first 2 weeks of ART and increased with time. ART reduced total HIV DNA levels by 20-fold after 2 weeks and 316-fold after 3 years. Therefore, very early ART offers the opportunity to significantly reduce the frequency of cells harboring HIV DNA.


Clinical Infectious Diseases | 2017

Persistent, Albeit Reduced, Chronic Inflammation in Persons Starting Antiretroviral Therapy in Acute HIV Infection

Irini Sereti; Shelly J. Krebs; Nittaya Phanuphak; James L. K. Fletcher; Bonnie M. Slike; Suteeraporn Pinyakorn; Robert J. O'Connell; Adam Rupert; Nicolas Chomont; Victor Valcour; Jerome H. Kim; Merlin L. Robb; Nelson L. Michael; Jintanat Ananworanich; Netanya S. Utay

Background.  Serious non-AIDS events cause substantial disease and death despite human immunodeficiency virus (HIV) suppression with antiretroviral therapy (ART). Biomarkers of inflammation, coagulation cascade activation, and fibrosis predict these end-organ events. We aimed to determine whether ART initiation during acute HIV infection would attenuate changes in these biomarker levels. Methods.  Plasma samples were obtained from participants starting ART during acute or chronic HIV infection and from HIV-uninfected participants from Bangkok, Thailand. Biomarkers of inflammation (C-reactive protein [CRP], interleukin 6, soluble interleukin 6 receptor [sIL-6R], soluble gp130, tumor necrosis factor [TNF]), enterocyte turnover (intestinal fatty acid binding protein [I-FABP]), lipopolysaccharide-induced monocyte activation (soluble CD14 [sCD14]), coagulation cascade activation [D-dimer], and fibrosis (hyaluronic acid [HA]) were measured at baseline and through 96 weeks of ART. Results.  CRP, TNF, sIL-6R, I-FABP, sCD14, D-dimer, and HA levels were elevated in acute HIV infection. Early ART was associated with increased I-FABP levels but normalization of TNF, sIL-6R, and D-dimer levels. CRP, sCD14, and HA levels decreased during ART but remained elevated compared with HIV-uninfected participants. Higher sCD14, CRP, and D-dimer levels were associated with higher peripheral blood mononuclear cell and gut integrated HIV DNA levels. Decreases in sCD14 and CRP levels were correlated with increases in CD4 T-cell counts. Conclusions.  ART initiated in early acute HIV infection was associated with normalization of the coagulation cascade and several systemic inflammatory biomarkers, but the acute-phase response, enterocyte turnover, monocyte activation, and fibrosis biomarkers remained elevated. Additional interventions to attenuate inflammation may be needed to optimize clinical outcomes in persons with HIV infection.


PLOS ONE | 2013

HIV DNA Reservoir Increases Risk for Cognitive Disorders in cART-Naïve Patients

Victor Valcour; Jintanat Ananworanich; Melissa Agsalda; Napapon Sailasuta; Thep Chalermchai; Alexandra Schuetz; Cecilia Shikuma; Chin-Yuan Liang; Supunee Jirajariyavej; Pasiri Sithinamsuwan; Somporn Tipsuk; David B. Clifford; Robert H. Paul; James L. K. Fletcher; Mary Marovich; Bonnie M. Slike; Victor DeGruttola; Bruce Shiramizu

Objectives Cognitive impairment remains frequent in HIV, despite combination antiretroviral therapy (cART). Leading theories implicate peripheral monocyte HIV DNA reservoirs as a mechanism for spread of the virus to the brain. These reservoirs remain present despite cART. The objective of this study was to determine if the level of HIV DNA in CD14+ enriched monocytes predicted cognitive impairment and brain injury. Methods We enrolled 61 cART-naïve HIV-infected Thais in a prospective study and measured HIV DNA in CD14+ enriched monocyte samples in a blinded fashion. We determined HAND diagnoses by consensus panel and all participants underwent magnetic resonance spectroscopy (MRS) to measure markers of brain injury. Immune activation was measured via cytokines in cerebrospinal fluid (CSF). Results The mean (SD) age was 35 (6.9) years, CD4 T-lymphocyte count was 236 (139) and log10 plasma HIV RNA was 4.8 (0.73). Twenty-eight of 61 met HAND criteria. The log10 CD14+ HIV DNA was associated with HAND in unadjusted and adjusted models (p = 0.001). There was a 14.5 increased odds ratio for HAND per 1 log-value of HIV DNA (10-fold increase in copy number). Plasma CD14+ HIV DNA was associated with plasma and CSF neopterin (p = 0.023) and with MRS markers of neuronal injury (lower N-acetyl aspartate) and glial dysfunction (higher myoinositol) in multiple brain regions. Interpretation Reservoir burden of HIV DNA in monocyte-enriched (CD14+) peripheral blood cells increases risk for HAND in treatment-naïve HIV+ subjects and is directly associated with CSF immune activation and both brain injury and glial dysfunction by MRS.


AIDS | 2015

Impact of nucleic acid testing relative to antigen/antibody combination immunoassay on the detection of acute HIV infection.

Mark S. de Souza; Nittaya Phanuphak; Suteeraporn Pinyakorn; Rapee Trichavaroj; Supanit Pattanachaiwit; Nitiya Chomchey; James L. K. Fletcher; Eugene Kroon; Nelson L. Michael; Praphan Phanuphak; Jerome H. Kim; Jintanat Ananworanich

Objective:To assess the addition of HIV nucleic acid testing (NAT) to fourth-generation (4thG) HIV antigen/antibody combination immunoassay in improving detection of acute HIV infection (AHI). Methods:Participants attending a major voluntary counseling and testing site in Thailand were screened for AHI using 4thG HIV antigen/antibody immunoassay and sequential less sensitive HIV antibody immunoassay. Samples nonreactive by 4thG antigen/antibody immunoassay were further screened using pooled NAT to identify additional AHI. HIV infection status was verified following enrollment into an AHI study with follow-up visits and additional diagnostic tests. Results:Among 74 334 clients screened for HIV infection, HIV prevalence was 10.9% and the overall incidence of AHI (N = 112) was 2.2 per 100 person-years. The inclusion of pooled NAT in the testing algorithm increased the number of acutely infected patients detected, from 81 to 112 (38%), relative to 4thG HIV antigen/antibody immunoassay. Follow-up testing within 5 days of screening marginally improved the 4thG immunoassay detection rate (26%). The median CD4+ T-cell count at the enrollment visit was 353 cells/&mgr;l and HIV plasma viral load was 598 289 copies/ml. Conclusion:The incorporation of pooled NAT into the HIV testing algorithm in high-risk populations may be beneficial in the long term. The addition of pooled NAT testing resulted in an increase in screening costs of 22% to identify AHI: from


Clinical Infectious Diseases | 2016

Initiation of Antiretroviral Therapy During Acute HIV-1 Infection Leads to a High Rate of Nonreactive HIV Serology

Mark S. de Souza; Suteeraporn Pinyakorn; Siriwat Akapirat; Supanit Pattanachaiwit; James L. K. Fletcher; Nitiya Chomchey; Eugene Kroon; Sasiwimol Ubolyam; Nelson L. Michael; Merlin L. Robb; Praphan Phanuphak; Jerome H. Kim; Nittaya Phanuphak; Jintanat Ananworanich

8.33 per screened patient to


Journal of Acquired Immune Deficiency Syndromes | 2015

Neuropsychological Impairment in Acute HIV and the Effect of Immediate Antiretroviral Therapy.

Idil Kore; Jintanat Ananworanich; Victor Valcour; James L. K. Fletcher; Thep Chalermchai; Robert H. Paul; Jesse Reynolds; Somporn Tipsuk; Sasiwimol Ubolyam; Somprartthana Rattanamanee; Linda L. Jagodzinski; Jerome H. Kim; Serena Spudich

10.16. Risk factors of the testing population should be considered prior to NAT implementation given the additional testing complexity and costs.


Neurology | 2016

Neurologic signs and symptoms frequently manifest in acute HIV infection

Joanna Hellmuth; James L. K. Fletcher; Victor Valcour; Eugene Kroon; Jintanat Ananworanich; Jintana Intasan; Sukalaya Lerdlum; Jared Narvid; Mantana Pothisri; Isabel E. Allen; Shelly J. Krebs; Bonnie M. Slike; Peeriya Prueksakaew; Linda L. Jagodzinski; Suwanna Puttamaswin; Nittaya Phanuphak; Serena Spudich

BACKGROUND Third- and fourth-generation immunoassays (IAs) are widely used in the diagnosis of human immunodeficiency virus (HIV) infection. Antiretroviral therapy (ART) during acute HIV infection (AHI) may impact HIV-specific antibodies, with failure to develop antibody or seroreversion. We report on the ability of diagnostic tests to detect HIV-specific antibodies in Thai participants initiating ART during AHI. METHODS Participants with detectable plasma HIV RNA but nonreactive HIV-specific immunoglobulin G, enrolled in an AHI study, were offered immediate initiation of ART. Participants were tested at initiation and at 12 and 24 weeks following treatment using standard second-, third-, and fourth-generation IAs and Western blot (WB). RESULTS Participants (N = 234) initiating ART at a median of 19 days (range, 1-62 days) from HIV exposure demonstrated different frequencies of reactivity prior to and following 24 weeks of ART depending on the IA. Third-generation IA nonreactivity prior to ART was 48%, which decreased to 4% following ART (P < .001). Fourth-generation IA nonreactivity was 18% prior to ART and 17% following ART (P = .720). Negative WB results were observed in 89% and 12% of participants prior to and following 24 weeks of ART, respectively (P < .001). Seroreversion to nonreactivity during ART was observed to at least one of the tests in 20% of participants, with fourth-generation IA demonstrating the highest frequency (11%) of seroreversion. CONCLUSIONS HIV-specific antibodies may fail to develop and, when detected, may decline when ART is initiated during AHI. Although fourth-generation IA was the most sensitive at detecting AHI prior to ART, third-generation IA was the most sensitive during treatment. CLINICAL TRIALS REGISTRATION NCT00796146 and NCT00796263.


The Journal of Infectious Diseases | 2015

Absence of Cerebrospinal Fluid Signs of Neuronal Injury Before and After Immediate Antiretroviral Therapy in Acute HIV Infection

Michael J. Peluso; Victor Valcour; Jintanat Ananworanich; Pasiri Sithinamsuwan; Thep Chalermchai; James L. K. Fletcher; Sukalya Lerdlum; Nitiya Chomchey; Bonnie M. Slike; Napapon Sailasuta; Magnus Gisslén; Henrik Zetterberg; Serena Spudich

Objective:To investigate neuropsychological performance (NP) during acute HIV infection (AHI) before and after combination antiretroviral therapy (cART). Design:Prospective study of Thai AHI participants examined at 3 and 6 months after initiation of cART. Methods:Thirty-six AHI participants were evaluated pre-cART at median 19 days since HIV exposure and 3 and 6 months after cART with the Grooved Pegboard test, Color Trails 1 & 2 (CT1, CT2), and Trail Making Test A. Raw scores were standardized to 251 age- and education-matched HIV-uninfected Thais. To account for learning effects, change in NP performance was compared with that of controls at 6 months. Analyses included multivariable regression, nonparametric repeated measures analysis of variance, and Mann–Whitney U test. Results:Baseline NP scores for the AHI group were within normal range (z-scores range: −0.26 to −0.13). NP performance improved on CT1, CT2, and Trail Making Test A in the initial 3 months (P < 0.01) with no significant change during the last 3 months. Only improvement in CT1 was greater than that seen in controls at 6 months (P = 0.018). Participants who performed >1 SD below normative means on ≥2 tests (n = 8) exhibited higher baseline cerebrospinal fluid HIV RNA (P = 0.047) and had no improvement after cART. Conclusions:Most AHI individuals had normal NP performance, and early cART slightly improved their psychomotor function. However, approximately 25% had impaired NP performance, which correlated with higher cerebrospinal fluid HIV RNA, and these abnormalities were not reversed by early cART possibly indicating limited reversibility of cognitive impairment in a subset of AHI individuals.


Journal of Acquired Immune Deficiency Syndromes | 2016

Neuronal-Glia Markers by Magnetic Resonance Spectroscopy in HIV Before and After Combination Antiretroviral Therapy.

Sailasuta N; Jintanat Ananworanich; Sukalaya Lerdlum; Pasiri Sithinamsuwan; James L. K. Fletcher; Somporn Tipsuk; Pothisri M; Jadwattanakul T; Thep Chalermchai; Catella S; Edgar Busovaca; Desai A; Robert H. Paul; Valcour

Objective: To determine the incidence, timing, and severity of neurologic findings in acute HIV infection (pre–antibody seroconversion), as well as persistence with combination antiretroviral therapy (cART). Methods: Participants identified with acute HIV were enrolled, underwent structured neurologic evaluations, immediately initiated cART, and were followed with neurologic evaluations at 4 and 12 weeks. Concurrent brain MRIs and both viral and inflammatory markers in plasma and CSF were obtained. Results: Median estimated HIV infection duration was 19 days (range 3–56) at study entry for the 139 participants evaluated. Seventy-three participants (53%) experienced one or more neurologic findings in the 12 weeks after diagnosis, with one developing a fulminant neurologic manifestation (Guillain-Barré syndrome). A total of 245 neurologic findings were noted, reflecting cognitive symptoms (33%), motor findings (34%), and neuropathy (11%). Nearly half of the neurologic findings (n = 121, 49%) occurred at diagnosis, prior to cART initiation, and most of these (n = 110, 90%) remitted concurrent with 1 month on treatment. Only 9% of neurologic findings (n = 22) persisted at 24 weeks on cART. Nearly all neurologic findings (n = 236, 96%) were categorized as mild in severity. No structural neuroimaging abnormalities were observed. Participants with neurologic findings had a higher mean plasma log10 HIV RNA at diagnosis compared to those without neurologic findings (5.9 vs 5.4; p = 0.006). Conclusions: Acute HIV infection is commonly associated with mild neurologic findings that largely remit while on treatment, and may be mediated by direct viral factors. Severe neurologic manifestations are infrequent in treated acute HIV.

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Jintanat Ananworanich

Henry M. Jackson Foundation for the Advancement of Military Medicine

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Suteeraporn Pinyakorn

Walter Reed Army Institute of Research

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Victor Valcour

University of California

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Merlin L. Robb

Walter Reed Army Institute of Research

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Eugene Kroon

Chulalongkorn University

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Nelson L. Michael

Walter Reed Army Institute of Research

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Jerome H. Kim

International Vaccine Institute

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Somporn Tipsuk

University of California

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