Gebremedhin Gebremicael

Mr. Gebremedhin Gebremicael

orcid

Research Focus & Metrics

Academic Career Length

14Years (2013-Present)

(Calculated once Scilit publication data is synced: current year − year of first publication + 1)

Representative Publications

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8 February 2018 in Scientific Reports
Verified
Journal Article
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NCNovel N Chegou
Novel N Chegou
JSJayne S. Sutherland
Jayne S. Sutherland
ANAnna-Ritah Namuganga
Anna-Ritah Namuganga
PCPaul Lam Corstjens
Paul Lam Corstjens
AGAnnemieke Geluk
Annemieke Geluk
SIScholastica Iipinge
Scholastica Iipinge
We investigated host-derived biomarkers that were previously identified in QuantiFERON supernatants, in a large pan-African study. We recruited individuals presenting with symptoms of pulmonary TB at seven peripheral healthcare facilities in six African countries, prior to assessment for TB disease. We then evaluated the concentrations of 12 biomarkers in stored QuantiFERON supernatants using the Luminex platform. Based on laboratory, clinical and radiological findings and a pre-established algorithm, participants were classified as TB disease or other respiratory diseases(ORD). Of the 514 individuals included in the study, 179(34.8%) had TB disease, 274(51.5%) had ORD and 61(11.5%) had an uncertain diagnosis. A biosignature comprising unstimulated IFN-γ, MIP-1β, TGF-α and antigen-specific levels of TGF-α and VEGF, identified on a training sample set (n = 311), validated by diagnosing TB disease in the test set (n = 134) with an AUC of 0.81(95% CI, 0.76–0.86), corresponding to a sensitivity of 64.2%(95% CI, 49.7–76.5%) and specificity of 82.7%(95% CI, 72.4–89.9%). Host biomarkers detected in QuantiFERON supernatants can contribute to the diagnosis of active TB disease amongst people presenting with symptoms requiring investigation for TB disease, regardless of HIV status or ethnicity in Africa.

1 February 2019 in International Journal of Infectious Diseases
Verified
Journal Article
Open access
DKDesta Kassa
Desta Kassa
GGGebremedhin Gebremicael
Gebremedhin Gebremicael
TTTesfaye Tilahun
Tesfaye Tilahun
AGAbenezer Giberhiwot
Abenezer Giberhiwot
YAYemane Abrha
Yemane Abrha
YAYibeltal Assefa
Yibeltal Assefa
This study was performed to determine the trends in seroprevalence of four major sexually transmitted infections (STIs) (HIV, hepatitis B virus (HBV), herpes simplex virus type 2 (HSV-2), and syphilis) over a 10-year period (2005-2014) in pregnant women in Ethiopia. Pregnant women (15-49 years old) who were enrolled in the antenatal care-based national HIV surveillance were included. Serological tests for HIV, HBV, HSV-2, and syphilis were done on serum/plasma samples. A total of 4887 pregnant women were included. Results showed a decline in prevalence of these STIs by 40-60% over the 10 years (2005-2014): HIV (10.5% to 5.5%), syphilis (2.5% to 1.1%), HBV (12.6% to 6.7%), and HSV-2 (47.5% to 28.5%). In 2014, 109/4887 (2.2%) women had triple infections. In 2005, 2007, and 2009, the prevalence of HSV-2 in the older age group (35-45 years) (47.1%, 47.4%, and 50.0%, respectively) was higher than that in the younger age group (15-24 years) (40.9%, 19.5%, and 20.2%, respectively). Age category (Chi-square=22.4, p40% was seen over the years in Ethiopia. However, an intermediate endemicity level of HBV and higher prevalence of HIV and HSV-2 by 2014, suggest the need to strengthen prevention strategy for STIs.


1 January 2013 in AIDS Research and Therapy
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Journal Article
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DKDesta Kassa
Desta Kassa
GGGebremedhin Gebremicael
Gebremedhin Gebremicael
YAYodit Alemayehu
Yodit Alemayehu
DWDawit Wolday
Dawit Wolday
TMTsehaynesh Messele
Tsehaynesh Messele
DBDebbie van Baarle
Debbie van Baarle
HIV/TB coinfection remains a major challenge even after the initiation of HAART. Little is known about Mycobacterium tuberculosis (Mtb) specific immune restoration in relation to immunologic and virologic outcomes after long-term HAART during co-infections with latent and active TB. A total of 232 adults, including 59 HIV patients with clinical TB (HIV + TB+), 125 HIV patients without clinical TB (HIV + TB-), 13 HIV negative active TB patients (HIV-TB+), and 10 HIV negative Tuberculin Skin TST positive (HIV-TST+), and 25 HIV-TST- individuals were recruited. HAART was initiated in 113 HIV + patients (28 TB + and 85 TB-), and anti-TB treatment for all TB cases. CD4+ T-cell count, HIV RNA load, and IFN-γ responses to ESAT-6/CFP-10 were measured at baseline, 6 months (M6), 18 months (M18) and 24 months (M24) after HAART initiation. The majority of HIV + TB- (70%, 81%, 84%) as well as HIV + TB + patients (60%, 77%, 80%) had virologic success (HIV RNA < 50 copies/ml) by M6, M18 and M24, respectively. HAART also significantly increased CD4+ T-cell counts at 2 years in HIV + TB + (from 110.3 to 289.9 cells/μl), HIV + TB- patients (197.8 to 332.3 cells/μl), HIV + TST- (199 to 347 cells/μl) and HIV + TST + individuals (195 to 319 cells/μl). Overall, there was no significant difference in the percentage of patients that achieved virologic success and in total CD4+ counts increased between HIV patients with and without TB or LTBI. The Mtb specific IFN-γ response at baseline was significantly lower in HIV + TB + (3.6 pg/ml) compared to HIV-TB + patients (34.4 pg/ml) and HIV + TST + (46.3 pg/ml) individuals; and in HIV-TB + patients compared to HIV-TST + individuals (491.2 pg/ml). By M18 on HAART, the IFN-γ response remained impaired in HIV + TB + patients (18.1 pg/ml) while it normalized in HIV + TST + individuals (from 46.3 to 414.2 pg/ml). Our data show that clinical and latent TB infections do not influence virologic and immunologic outcomes of ART in HIV patients. Despite this, HAART was unable to restore optimal TB responsiveness as measured by Mtb specific IFN-γ response in HIV/TB patients. Improvement of Mtb-specific immune restoration should be the focus of future therapeutic strategies.

10 December 2019 in PLOS ONE
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Journal Article
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GGGebremedhin Gebremicael
Gebremedhin Gebremicael
DKDesta Kassa
Desta Kassa
YAYodit Alemayehu
Yodit Alemayehu
AGAtsbeha Gebreegziaxier
Atsbeha Gebreegziaxier
YKYonas Kassahun
Yonas Kassahun
MHMariëlle C Haks
Mariëlle C Haks
Validation of previously identified candidate biomarkers and identification of additional candidate gene expression profiles to facilitate diagnosis of tuberculosis (TB) disease and monitoring treatment responses in the Ethiopian context is vital for improving TB control in the future. Expression levels of 105 immune-related genes were determined in the blood of 80 HIV-negative study participants composed of 40 active TB cases, 20 latent TB infected individuals with positive tuberculin skin test (TST+), and 20 healthy controls with no Mycobacterium tuberculosis (Mtb) infection (TST-), using focused gene expression profiling by dual-color Reverse-Transcription Multiplex Ligation-dependent Probe Amplification assay. Gene expression levels were also measured six months after anti-TB treatment (ATT) and follow-up in 38 TB patients. The expression of 15 host genes in TB patients could accurately discriminate between TB cases versus both TST+ and TST- controls at baseline and thus holds promise as biomarker signature to classify active TB disease versus latent TB infection in an Ethiopian setting. Interestingly, the expression levels of most genes that markedly discriminated between TB cases versus TST+ or TST- controls did not normalize following completion of ATT therapy at 6 months (except for PTPRCv1, FCGR1A, GZMB, CASP8 and GNLY) but had only fully normalized at the 18 months follow-up time point. Of note, network analysis comparing TB-associated host genes identified in the current HIV-negative TB cohort to TB-associated genes identified in our previously published Ethiopian HIV-positive TB cohort, revealed an over-representation of pattern recognition receptors including TLR2 and TLR4 in the HIV-positive cohort which was not seen in the HIV-negative cohort. Moreover, using ROC cutoff ≥ 0.80, FCGR1A was the only marker with classifying potential between TB infection and TB disease regardless of HIV status. Our data indicate that complex gene expression signatures are required to measure blood transcriptomic responses during and after successful ATT to fully diagnose TB disease and characterise drug-induced relapse-free cure, combining genes which resolve completely during the 6-months treatment phase of therapy with genes that only fully return to normal levels during the post-treatment resolution phase.

1 November 2017 in International Journal of Chronic Diseases
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Journal Article
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GGGebremedhin Gebremicael
Gebremedhin Gebremicael
YAYemane Amare
Yemane Amare
FCFeyissa Challa
Feyissa Challa
AGAtsbeha Gebreegziabxier
Atsbeha Gebreegziabxier
GMGirmay Medhin
Girmay Medhin
DKDesta Kassa
Desta Kassa
Background. Understanding whether the preceding low lipid profile leads to active tuberculosis (TB) or active TB leads to low lipid profile is crucial.Methods. Lipid profile concentrations were determined from 159 study participants composed of 93 active TB patients [44 HIV coinfected (HIV+TB+) and 49 HIV negative (HIV−TB+)], 41 tuberculin skin test (TST) positive cases [17 HIV coinfected (HIV+TST+) and 24 HIV negative (HIV−TST+)], and 25 healthy controls (HIV−TST−). Cobas Integra 400 Plus was used to determine lipid profiles concentration level.Results. The concentrations of total cholesterol (TC), triglyceride (TG), low-density lipoprotein cholesterol (LDL-C), and high-density lipoprotein cholesterol (HDL-C) in HIV−TB+ patients were significantly lower compared to HIV−TST+ and to HIV−TST− individuals. Similarly, the concentrations of the TC, LDL-C, and HDL-C in HIV+TB+ were significantly lower compared to HIV−TB+ patients. After the 6 months of anti-TB treatment (ATT), the concentration levels of TC, LDL-C, and HDL-C in HIV−TB+ patients were higher compared to the baseline concentration levels, while they were not significantly different compared to that of HIV−TST+ concentration.Conclusion. The low concentration of lipid profiles in TB patients may be a consequence of the disease and significantly increased in TB patients after treatment.