Ivan S. Mfouo-Tynga

Dr. Ivan S. Mfouo-Tynga

Centre International de Recherches Médicales de Franceville, Franceville, Haut-Ogooué, Gabon

Research Focus & Metrics

Academic Career Length

7Years (2020-Present)

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

Representative Publications

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1 June 2021 in Photodiagnosis and Photodynamic Therapy
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Journal Article
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IMIvan S. Mfouo-Tynga
Ivan S. Mfouo-Tynga
LDLucas D. Dias
Lucas D. Dias
NINatalia M. Inada
Natalia M. Inada
CKCristina Kurachi
Cristina Kurachi

14 October 2020 in Biomimetics
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Journal Article
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LDLucas Dias
Lucas Dias
IMIvan S. Mfouo-Tynga
Ivan S. Mfouo-Tynga
Chlorophylls, which are chlorin-type photosensitizers, are known as the key building blocks of nature and are fundamental for solar energy metabolism during the photosynthesis process. In this regard, the utilization of bioinspired chlorin analogs as photosensitizers for photodynamic therapy constitutes an evolutionary topic of research. Moreover, carbon nanomaterials have been widely applied in photodynamic therapy protocols due to their optical characteristics, good biocompatibility, and tunable systematic toxicity. Herein, we review the literature related to the applications of chlorin-based photosensitizers that were functionalized onto carbon nanomaterials for photodynamic and photothermal therapies against cancer. Rather than a comprehensive review, we intended to highlight the most important and illustrative examples over the last 10 years.

16 October 2022 in Pharmaceuticals
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IMIvan S. Mfouo-Tynga
Ivan S. Mfouo-Tynga
Augustin MOUINGA ONDEMEAugustin MOUINGA ONDEME
Augustin MOUINGA ONDEME
The recent COVID-19 pandemic outbreak and arising complications during treatments have highlighted and demonstrated again the evolving ability of microorganisms, especially viral resistance to treatment as they develop into new and strong strains. The search for novel and effective treatments to counter the effects of ever-changing viruses is undergoing. Although it is an approved procedure for treating cancer, photodynamic therapy (PDT) was first used against bacteria and has now shown potential against viruses and certain induced diseases. PDT is a multi-stage process and uses photosensitizing molecules (PSs) that accumulate in diseased tissues and eradicates them after being light-activated in the presence of oxygen. In this review, studies describing viruses and their roles in disrupting cell regulation mechanisms and signaling pathways and facilitating tumorigenesis were described. With the development of innovative “or smart” PSs through the use of nanoparticles and two-photon excitation, among other strategies, PDT can boost immune responses, inactivate viral infections, and eradicate neoplastic cells. Visualization and monitoring of biological processes can be achieved in real-time with nanomedicines and better tissue penetration strategies. After photodynamic inactivation of viruses, signaling pathways seem to be restored but the underlying mechanisms are still to be elucidated. Light-mediated treatments are suitable to manage both oncogenic viral infections and induced neoplasia.

4 January 2024 in Viruses
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Augustin MOUINGA ONDEMEAugustin MOUINGA ONDEME
Augustin MOUINGA ONDEME
LMLONGO PENDY Michel
LONGO PENDY Michel
IKIvan Cyr Moussadji Kinga
Ivan Cyr Moussadji Kinga
NBNgoubangoye Barthelemy
Ngoubangoye Barthelemy
PBPamela Moussavou Boundzanga
Pamela Moussavou Boundzanga
ENEdgard-Brice Ngoungou
Edgard-Brice Ngoungou
The Human Immunodeficiency Virus/Acquired Immunodeficiency Syndrome (HIV/AIDS) is still one of the main causes of death in sub-Saharan Africa. Antiretroviral therapies (ARTs) have significantly improved the health conditions of people living with HIV/AIDS (PLWHA). Consequently, a significant drop in morbidity and mortality, along with a reduced incidence of opportunistic infections (OIs), has been observed. However, certain atypical and biological profiles emerge in ART patients post-examination. The objective of this study was to identify the risk factors that contributed to the onset of OIs in HIV patients undergoing ART in Gabon. Epidemiological and biological data were obtained from medical records (2017 to 2019) found at the outpatient treatment centre (CTA) of Franceville in Gabon. Samples for blood count, CD4, and viral load analysis at CIRMF were collected from PLWHA suffering from other pathogen-induced conditions. A survey was carried out and data were analysed using Rstudio 4.0.2 and Excel 2007 software. Biological and socio-demographic characteristics were examined concerning OIs through both a univariate analysis via Fisher’s exact tests or chi2 (χ2), and a multivariate analysis via logistic regression. Out of the 300 participants initially selected, 223 were included in the study, including 154 (69.05%) women and 69 (30.95%) men. The mean age was 40 (38.6; 41.85), with individuals ranging from 2 to 77 years old. The study cohort was classified into five age groups (2 to 12, 20 to 29, 30 to 39, 40 to 49, and 50 to 77 years old), among which the groups aged 30 to 39 and 40 to 49 emerged as the largest, comprising 68 (30.5%) and 75 (33.6%) participants, respectively. It was noted that 57.9% of PLWHA had developed OIs and three subgroups were distinguished, with parasitic, viral, and bacterial infections present in 18%, 39.7%, and 55.4% of cases, respectively. There was a correlation between being male and having a low CD4 T-cell count and the onset of OIs. The study revealed a high overall prevalence of OIs, and extending the study to other regions of Gabon would yield a better understanding of the risk factors associated with the onset of these infections.

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AMAnthony Idam Mamimandjiami
Anthony Idam Mamimandjiami
JEJéordy Dimitri Engone-Ondo
Jéordy Dimitri Engone-Ondo
PBPamela Moussavou Boundzanga
Pamela Moussavou Boundzanga
Augustin MOUINGA ONDEMEAugustin MOUINGA ONDEME
Augustin MOUINGA ONDEME
IMIvan S. Mfouo-Tynga
Ivan S. Mfouo-Tynga
Kaposi’s sarcoma (KS) is a tumor that primarily affects the skin, caused by a multifactorial pathogenesis mediated through immune dysfunction, often leading to increased morbidity and mortality in Sub-Saharan Africa (SSA). Human herpesvirus-8, also known as Kaposi’s sarcoma-associated herpesvirus (KSHV), induces an infection that can facilitate the pathogenesis of KS and other conditions. All KSHV subtypes depend on the expression of specific markers, such as K1 proteins, which play critical roles in their life cycles. The infection is unevenly scattered worldwide, with individuals infected with human immunodeficiency virus (HIV) and pregnant women being among the most vulnerable groups. HIV infection and related effectors, such as TAT proteins, have substantial impacts on KSHV infectiousness, angiogenesis, various signaling pathways, and KS pathogenesis. Africa endures the heaviest burden of KS, which affects both men and women, sometimes from an early age. KS’s pathogenesis and underlying mechanisms remain unclear; this study aims to highlight the dynamics to be considered in managing and mitigating the burden of KS in SSA. In that region, certain infections are endemic and can cause intermediate health damage leading to KS tumorigenesis, highlighting the link between non-communicable and communicable diseases.

14 August 2025 in Diseases
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MMMarcelle MBOUMBA-MBOUMBA
Marcelle MBOUMBA-MBOUMBA
Augustin MOUINGA ONDEMEAugustin MOUINGA ONDEME
Augustin MOUINGA ONDEME
PBPamela Moussavou Boundzanga
Pamela Moussavou Boundzanga
JEJéordy Dimitri Engone-Ondo
Jéordy Dimitri Engone-Ondo
RMRoseanne Mounanga Mourimarodi
Roseanne Mounanga Mourimarodi
IMIvan S. Mfouo-Tynga
Ivan S. Mfouo-Tynga
Background/Objectives. Women living with human immunodeficiency virus (WLWH) have a six-fold higher risk of developing cervical cancer associated with high-risk human Papillomavirus (HR-HPV) than HIV-negative women. We herein assessed HR-HPV genotype distribution and plasma levels of the cancer antigen 125 (CA-125) in WLWH in a rural town in Gabon, in Central Africa. Methods. Adult WLWH attending the local HIV outpatient center were prospectively enrolled and underwent cervical visual inspection and cervicovaginal and blood sampling. HIV RNA load and CA-125 levels were measured from plasma using the Cepheid® Xpert® HIV-1 Viral Load kit and BioMérieux VIDAS® CA-125 II assay, respectively. HPV detection and genotyping were performed via a nested polymerase chain reaction (MY09/11 and GP5+/6+), followed by sequencing. Results. Fifty-eight WLWH (median age: 52 years) were enrolled. Median CD4 count was 547 cells/µL (IQR: 412.5–737.5) and HIV RNA load 4.88 Log10 copies/mL (IQR: 3.79–5.49). HPV prevalence was 68.96%, with HR-HPV detected in 41.37% of women. Among HR-HPV-positive samples, 87.5% (21/24) were genotypes targeted by the Gardasil vaccine, while 12.5% (3/24) were non-vaccine types. Predominant HR-HPV types included HPV-16 (13.8%), HPV-33 (10.34%), HPV-35 (5.17%), HPV-31, and HPV-58 (3.45%). Most participants had normal cervical cytology (62.07%), and a minority (14.29%) had elevated CA-125 levels, with no correlation to cytological abnormalities. Conclusions. In the hinterland of Gabon, WLWH are facing an unsuspected yet substantial burden of cervical HR-HPV infection and a neglected risk for cervical cancer. Strengthening cervical cancer prevention through targeted HPV vaccination, sexual education, and accessible screening strategies will help in mitigating associated risk.