Clinton Odhiambo Onyango

Mr. Clinton Odhiambo Onyango

orcid

Research Focus & Metrics

Academic Career Length

5Years (2022-Present)

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

Representative Publications

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3 October 2024 in Pathogens
Verified
Journal Article
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COClinton Odhiambo Onyango
Clinton Odhiambo Onyango
SASAMUEL B. ANYONA
SAMUEL B. ANYONA
IHIVY HURWITZ
IVY HURWITZ
EREvans Raballah
Evans Raballah
SWSharley A. Wasena
Sharley A. Wasena
DPDouglas J Perkins
Douglas J Perkins
Severe malarial anemia (SMA, Hb < 6.0 g/dL) is a leading cause of childhood morbidity and mortality in holoendemic Plasmodium falciparum transmission zones. This study explored the entire expressed human transcriptome in whole blood from 66 Kenyan children with non-SMA (Hb ≥ 6.0 g/dL, n = 41) and SMA (n = 25), focusing on host immune response networks. RNA-seq analysis revealed 6862 differentially expressed genes, with equally distributed up-and down-regulated genes, indicating a complex host immune response. Deconvolution analyses uncovered leukocytic immune profiles indicative of a diminished antigenic response, reduced immune priming, and polarization toward cellular repair in SMA. Weighted gene co-expression network analysis revealed that immune-regulated processes are central molecular distinctions between non-SMA and SMA. A top dysregulated immune response signaling network in SMA was the HSP60-HSP70-TLR2/4 signaling pathway, indicating altered pathogen recognition, innate immune activation, stress responses, and antigen recognition. Validation with high-throughput gene expression from a separate cohort of Kenyan children (n = 50) with varying severities of malarial anemia (n = 38 non-SMA and n = 12 SMA) confirmed the RNA-seq findings. Proteomic analyses in 35 children with matched transcript and protein abundance (n = 19 non-SMA and n = 16 SMA) confirmed dysregulation in the HSP60-HSP70-TLR2/4 signaling pathway. Additionally, glutamine transporter and glutamine synthetase genes were differentially expressed, indicating altered glutamine metabolism in SMA. This comprehensive analysis underscores complex immune dysregulation and novel pathogenic features in SMA.

12 June 2024 in Nature Communications
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Journal Article
Open access
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SASAMUEL B. ANYONA
SAMUEL B. ANYONA
QCQuiying Cheng
Quiying Cheng
SWSharley A. Wasena
Sharley A. Wasena
SOShamim Wanjiku Osata
Shamim Wanjiku Osata
YGYan Guo
Yan Guo
DPDouglas J Perkins
Douglas J Perkins
This study on severe malarial anemia (SMA: Hb < 6.0 g/dL), a leading global cause of childhood morbidity and mortality, compares the entire expressed whole blood host transcriptome between Kenyan children (3-48 mos.) with non-SMA (Hb ≥ 6.0 g/dL, n = 39) and SMA (n = 18). Differential expression analyses reveal 1403 up-regulated and 279 down-regulated transcripts in SMA, signifying impairments in host inflammasome activation, cell death, and innate immune and cellular stress responses. Immune cell profiling shows decreased memory responses, antigen presentation, and immediate pathogen clearance, suggesting an immature/improperly regulated immune response in SMA. Module repertoire analysis of blood-specific gene signatures identifies up-regulation of erythroid genes, enhanced neutrophil activation, and impaired inflammatory responses in SMA. Enrichment analyses converge on disruptions in cellular homeostasis and regulatory pathways for the ubiquitin-proteasome system, autophagy, and heme metabolism. Pathway analyses highlight activation in response to hypoxic conditions [Hypoxia Inducible Factor (HIF)−1 target and Reactive Oxygen Species (ROS) signaling] as a central theme in SMA. These signaling pathways are also top-ranking in protein abundance measures and a Ugandan SMA cohort with available transcriptomic data. Targeted RNA-Seq validation shows strong concordance with our entire expressed transcriptome data. These findings identify key molecular themes in SMA pathogenesis, offering potential targets for new malaria therapies.

20 June 2023 in BMC Cancer
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POPerez K. Olewe
Perez K. Olewe
SAShehu Shagari Awandu
Shehu Shagari Awandu
EMElly O. Munde
Elly O. Munde
SASamuel B. Anyona
Samuel B. Anyona
EREvans Raballah
Evans Raballah
COCollins Ouma
Collins Ouma
Background: Epstein Barr virus (EBV)-associated endemic Burkitt’s Lymphoma pediatric cancer is associated with morbidity and mortality among children resident in holoendemic Plasmodium falciparum regions in western Kenya. P. falciparum exerts strong selection pressure on sickle cell trait (SCT), alpha thalassemia (-α3.7/αα), glucose-6-phosphate dehydrogenase (G6PD), and merozoite surface protein 2 (MSP-2) variants (FC27, 3D7) that confer reduced malarial disease severity. The current study tested the hypothesis that SCT, (-α3.7/αα), G6PD mutation and (MSP-2) variants (FC27, 3D7) are associated with an early age of EBV acquisition. Methods: Data on infant EBV infection status (< 6 and ≥ 6–12 months of age) was abstracted from a previous longitudinal study. Archived infant DNA (n = 81) and mothers DNA (n = 70) samples were used for genotyping hemoglobinopathies and MSP-2. The presence of MSP-2 genotypes in maternal DNA samples was used to indicate infant in-utero malarial exposure. Genetic variants were determined by TaqMan assays or standard PCR. Group differences were determined by Chi-square or Fisher’s analysis. Bivariate regression modeling was used to determine the relationship between the carriage of genetic variants and EBV acquisition. Results: EBV acquisition for infants < 6 months was not associated with -α3.7/αα (OR = 1.824, P = 0.354), SCT (OR = 0.897, P = 0.881), or G6PD [Viangchan (871G > A)/Chinese (1024 C > T) (OR = 2.614, P = 0.212)] and [Union (1360 C > T)/Kaiping (1388G > A) (OR = 0.321, P = 0.295)]. There was no relationship between EBV acquisition and in-utero exposure to either FC27 (OR = 0.922, P = 0.914) or 3D7 (OR = 0.933, P = 0.921). In addition, EBV acquisition in infants ≥ 6–12 months also showed no association with -α3.7/αα (OR = 0.681, P = 0.442), SCT (OR = 0.513, P = 0.305), G6PD [(Viangchan (871G > A)/Chinese (1024 C > T) (OR = 0.640, P = 0.677)], [Mahidol (487G > A)/Coimbra (592 C > T) (OR = 0.948, P = 0.940)], [(Union (1360 C > T)/Kaiping (1388G > A) (OR = 1.221, P = 0.768)], African A (OR = 0.278, P = 0.257)], or in utero exposure to either FC27 (OR = 0.780, P = 0.662) or 3D7 (OR = 0.549, P = 0.241). Conclusion: Although hemoglobinopathies (-α3.7/αα, SCT, and G6PD mutations) and in-utero exposure to MSP-2 were not associated with EBV acquisition in infants 0–12 months, novel G6PD variants were discovered in the population from western Kenya. To establish that the known and novel hemoglobinopathies, and in utero MSP-2 exposure do not confer susceptibility to EBV, future studies with larger sample sizes from multiple sites adopting genome-wide analysis are required.

23 February 2022 in JMIR Medical Education
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Journal Article
Open access
LJLynnMarie Jarratt
LynnMarie Jarratt
JSJenny Situ
Jenny Situ
RKRachel D King
Rachel D King
EREstefania Montanez Ramos
Estefania Montanez Ramos
HGHannah Groves
Hannah Groves
CLChristophe Gerard Lambert
Christophe Gerard Lambert
Background: On March 11, 2020, the New Mexico Governor declared a public health emergency in response to the COVID-19 pandemic. The New Mexico medical advisory team contacted University of New Mexico (UNM) faculty to form a team to consolidate growing information on severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) and its disease to facilitate New Mexico’s pandemic management. Thus, faculty, physicians, staff, graduate students, and medical students created the “UNM Global Health COVID-19 Intelligence Briefing.” Objective: In this paper, we sought to (1) share how to create an informative briefing to guide public policy and medical practice and manage information overload with rapidly evolving scientific evidence; (2) determine the qualitative usefulness of the briefing to its readers; and (3) determine the qualitative effect this project has had on virtual medical education. Methods: Microsoft Teams was used for manual and automated capture of COVID-19 articles and composition of briefings. Multilevel triaging saved impactful articles to be reviewed, and priority was placed on randomized controlled studies, meta-analyses, systematic reviews, practice guidelines, and information on health care and policy response to COVID-19. The finalized briefing was disseminated by email, a listserv, and posted on the UNM digital repository. A survey was sent to readers to determine briefing usefulness and whether it led to policy or medical practice changes. Medical students, unable to partake in direct patient care, proposed to the School of Medicine that involvement in the briefing should count as course credit, which was approved. The maintenance of medical student involvement in the briefings as well as this publication was led by medical students. Results: An average of 456 articles were assessed daily. The briefings reached approximately 1000 people by email and listserv directly, with an unknown amount of forwarding. Digital repository tracking showed 5047 downloads across 116 countries as of July 5, 2020. The survey found 108 (95%) of 114 participants gained relevant knowledge, 90 (79%) believed it decreased misinformation, 27 (24%) used the briefing as their primary source of information, and 90 (79%) forwarded it to colleagues. Specific and impactful public policy decisions were informed based on the briefing. Medical students reported that the project allowed them to improve on their scientific literature assessment, stay current on the pandemic, and serve their community. Conclusions: The COVID-19 briefings succeeded in informing and guiding New Mexico policy and clinical practice. The project received positive feedback from the community and was shown to decrease information burden and misinformation. The virtual platforms allowed for the continuation of medical education. Variability in subject matter expertise was addressed with training, standardized article selection criteria, and collaborative editing led by faculty.

16 October 2026 in Research Square
Verified
Preprint
Open access
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DPDouglas J Perkins
Douglas J Perkins
COClinton Odhiambo Onyango
Clinton Odhiambo Onyango
SOShamim Wanjiku Osata
Shamim Wanjiku Osata
SWSharley A. Wasena
Sharley A. Wasena
IHIVY HURWITZ
IVY HURWITZ
QCQuiying Cheng
Quiying Cheng
Malaria remains a leading cause of childhood morbidity and mortality in sub-Saharan Africa, with severe malarial anemia (SMA; hemoglobin (Hb) < 6.0 g/dL) representing one of the life-threatening complications of Plasmodium falciparum infection. While limited studies have examined host transcriptional responses in SMA, parasite transcriptional adaptations remain unexplored. Here, we performed parasite transcriptomic profiling in the same cohort of Kenyan children under five years of age in whom we previously characterized host transcriptional responses to SMA, including children presenting with SMA (n = 20) or non-SMA malaria (n = 40). Differential expression analysis identified 566 P. falciparum genes associated with SMA, predominantly involving up-regulated transcripts linked to proteostasis, translational regulation, stress-response pathways, and metabolic remodeling. Transcriptomic deconvolution indicated greater trophozoite and schizont representation in SMA, with reduced ring-stage and gametocyte signatures. Weighted gene co-expression network analysis and protein-protein interaction network analysis identified coordinated transcriptional programs enriched for proteasomal degradation, ubiquitin-mediated protein turnover, chaperone activity, RNA processing, and metabolic adaptation. XGBoost-SHAP modeling identified a small subset of parasite genes that captured much of the transcriptomic signal, classifying SMA from non-SMA malaria. Collectively, these findings define a distinct parasite transcriptional landscape in SMA characterized by coordinated stress adaptation and metabolic flexibility, highlighting proteostasis-associated pathways for further therapeutic investigation.