ResearchSpace
ResearchSpace is the institutional repository of the University of KwaZulu-Natal, unlocking knowledge, empowering impact, and preserving UKZN's research legacy.
Recent Submissions
Nippostrongylus brasiliensis and herpes simplex virus-2 co-infections: Impact on female genital tract microRNA and immune profiles, and potential role in cervical carcinogenesis.
(2025) Pillay, Roxanne.; Mkhize-Kwitshana, Zilungile Lynette.; Naidoo, Pragalathan.
Background:
Co-infections involving soil-transmitted helminths (STHs) and viral pathogens such as herpes simplex virus type 2 (HSV-2) remain poorly characterized, despite their overlapping prevalence in sub-Saharan Africa and other resource-poor regions. The immunomodulatory effects of STHs and the oncogenic potential of HSV-2 raise pertinent questions about whether STHs may alter host immunity and susceptibility to HSV-2 and influence molecular pathways associated with cervical cancer. MicroRNAs (miRNAs) are post-transcriptional regulators of gene expression, which play crucial roles in immune modulation, inflammation, and cancer-related pathways. This study aimed to characterize miRNA and mRNA expression profiles in the murine female genital tract (FGT) following single and co-infection with Nippostrongylus brasiliensis (Nb), a murine hookworm, and HSV-2, to elucidate potential molecular mechanisms by which helminth-induced immunoregulation may influence HSV-2 immunity and pathways implicated in cervical cancer.
Methods:
A comprehensive literature review was first conducted to assess existing knowledge on STH/HSV-2 co-infections and highlighted the biological plausibility and epidemiological significance of STH/HSV-2 co-infections and informed the conceptual framework for this investigation. The review also emphasised the potential role of miRNAs in regulating immune and disease pathways in the context of STH/HSV-2 co-infections. Experimentally, female BALB/c mice were either singly infected with Nb or HSV-2, co-infected with both pathogens, or left uninfected. Total RNA was extracted from FGT tissues and high-throughput next-generation sequencing was used to characterise miRNA and mRNA expression profiles in the FGT. Differential expression analysis was conducted using edgeR and limma packages in R. Ingenuity Pathway Analysis (IPA) was used to predict canonical pathways, biological functions, and to identify key immune and cancer-related pathways associated with differentially expressed (DE) miRNAs. Selected DE miRNAs were validated by RT-qPCR. RNA-sequencing (mRNA) data were functionally analysed using g: Profiler and visualized through protein–protein interaction networks constructed in Cytoscape, with hub gene and module identification via CytoHubba and MCODE.
Results:
MiRNA sequencing revealed eight DE miRNAs in Nb-infected FGT tissues (e.g., mmu-miR-218- 5p, mmu-miR-449a-5p, mmu-miR-497a-3p, mmu-miR-144-3p), and nine DE miRNAs in HSV- 2-infected tissues (e.g., mmu-miR-451a, mmu-miR-376a-3p, mmu-miR-205-3p, mmu-miR-103-3p), relative to uninfected controls. Notably, only one miRNA (mmu-miR-199a-5p) was DE in co-infected tissues, suggestive of helminth-induced immunomodulation and antagonism of HSV- 2-associated immune and transcriptomic responses. Several DE miRNAs identified have established roles in immune regulation and carcinogenesis within the female reproductive tract. IPA revealed enrichment of immune-related pathways such as neutrophil degranulation, interleukin (IL)-4 and IL-13 signaling, natural killer cell signaling, and ISGylation signaling. Cancer was predicted as a significantly enriched disease, particularly in the co-infected group. Complementary mRNA profiling demonstrated 368 DE genes in Nb-infected tissues (356 upregulated, 12 downregulated), with significant expression changes in Th2-related immune genes including C-C motif chemokine ligand 11 (Ccl11), C-C chemokine receptor type 2 (Ccr2), and CX3C chemokine receptor 1 (Cx3cr1). HSV-2-infected tissues yielded 140 DE genes (121 upregulated, 19 downregulated), with alterations in genes implicated in immune function [e.g., low-density lipoprotein receptor (Ldlr), calcium/calmodulin-dependent protein kinase ID (Camk1d), LDL Receptor Related Protein 8 (Lrp8), ectopic P-granules autophagy protein 5ho molog (Epg5)] and in cell cycle and sterol biosynthesis pathways. In contrast, co-infectedti ssues did not exhibit significant differential gene expression compared to uninfected controls, further supporting the potential immunomodulatory effect of Nb on anti-HSV-2 immune and transcriptomic responses.
Conclusion:
This study provides the first comprehensive analysis of miRNA and mRNA expression profiles in the murine FGT following Nb and HSV-2 single and co-infections, revealing distinct transcriptional and post-transcriptional signatures associated with helminth and viral infection. The suppression of transcriptomic responses during co-infection underscores the potential of helminth-mediated immunomodulation to alter anti-HSV-2 immunity and its potential to contribute to inflammation- and cancer-related pathways. These findings fill a critical gap in understanding the molecular interplay between STHs and HSV-2 and provide the groundwork for future mechanistic studies, including functional validation and translational research. The results are relevant for diagnostics, vaccine strategies, integrated disease control in co-endemic regions, and in understanding the potential links between co-infection and cervical cancer risk.
Community and clinical resistomes and mobilomes: a correlation.
(2025) Mahonisi, Khanyisa.; Essack, Sabiha Yusuf.; Mbanga, Joshua.; Maphumulo, Sandra.; Mpundu, Mirfin Mambwe.
Bacteria acquire antibiotic resistance genes (ARGs) through horizontal gene transfer or mutations. Colonization of healthy individuals with multidrug-resistant (MDR) bacteria therefore poses a public health concern, as these individuals may serve as reservoirs of antimicrobial resistance (AMR). This study compared the resistomes, mobilomes, and phylogenetic relationships of Escherichia coli and Klebsiella pneumoniae isolates from a regional hospital and nearby healthy community dwellers in uMgungundlovu District, using whole genome sequencing (WGS) and bioinformatics to assess AMR transmission directionality. Stool and clinical samples were collected, and presumptively identified isolates underwent antimicrobial susceptibility testing, extended-spectrum β-lactamase (ESBL) screening, and WGS. Bioinformatic analyses were conducted using RAST, ResFinder, CARD, PlasmidFinder, INTEGRALL, ISFinder, PGAP, MLST, BV-BRC, and iTOL. This study reports on 32 E. coli isolates (15 clinical and 17 community) and 14 K. pneumoniae isolates (6 clinical and 8 community) confirmed by WGS. Seven E. coli isolates (3 clinical and 4 community) and one community K. pneumoniae isolate were identified as ESBL producers, with E. coli from both settings sharing multiple resistance genes, including blaCTX-M-15, blaTEM-1B, dfrA17, sul1, sul2, aph(3'')-Ib, aph(6)- Id, qnrS1, mph(A), catA1, and tet(A), while K. pneumoniae isolates commonly carried blaSHV-1, blaTEM- 1B, sul1, sul2, aph(3'')-Ib, aph(6)-Id, qnrS1, and fosA5. Most of these ARGs were associated with insertion sequences and transposons in both settings. Among E. coli, the most common sequence types (STs) in both clinical and community isolates were ST131, ST10, and ST1193, while ST17 was shared among K. pneumoniae isolates. Phylogenetic analysis revealed clustering between clinical and community isolates, although clustering was less pronounced for K. pneumoniae. In conclusion, this study revealed the possibility of bidirectional AMR transmission between clinical and community settings. These findings highlight healthy individuals as potential reservoirs of resistance and strengthen the need to include community settings in AMR mitigation strategies.
The effects of chronic administration of Cannabidiol and Cannabidiol-Selexipag combination on haematological parameters, oxidative stress, BNP, and TNF-α in a rat model of Pulmonary Arterial Hypertension.
(2024) Gunpath, Chayil.; Nadar, Anand.
Background: Pulmonary arterial hypertension (PAH) is a severe condition characterized by elevated pulmonary artery pressure, leading to progressive cardiovascular impairment and high mortality rates. Current therapies often fall short of providing adequate symptom relief and disease management. This study evaluates the combined therapeutic potential of Cannabidiol (CBD) and Selexipag, assessing their effects on key biomarkers and haematological parameters associated with PAH.
Methods: In a preclinical model, PAH was induced in rats using monocrotaline (MCT), followed by treatment with CBD, Selexipag, or their combination. Biomarkers including B-type natriuretic peptide (BNP), total antioxidant capacity (T-AOC), and tumour necrosis factor-alpha (TNF-α) were measured to evaluate cardiovascular and inflammatory responses. Additionally, haematological parameters such as platelet count, and haemoglobin levels were assessed. Statistical analysis was conducted using Welch’s ANOVA and unpaired Welch’s T-Tests to determine the significance of treatment effects.
Results: The combination therapy of CBD and Selexipag was found to be significantly more effective in normalizing BNP and T-AOC levels compared to the individual treatments. This suggests that adjunctive therapy might enhance cardiovascular function and reduce oxidative stress. Despite CBD’s established anti-inflammatory properties, elevated TNF-α levels in the MCT-CBD group indicated a potential exacerbation of inflammation. This finding is at odds with previous literature on CBD’s effects, which may be influenced by specific experimental conditions or dosages. Haematological analysis revealed elevated platelet counts and haemoglobin levels, with increased platelet activation noted, which correlates with findings linking these parameters to PAH progression.
Discussion: The study underscores the potential of combining CBD with Selexipag as a promising approach for PAH management, showing improved biomarker profiles indicative of better cardiovascular function and oxidative stress mitigation. However, the unexpected rise in TNF-α levels with CBD treatment highlights the complexity of its anti-inflammatory effects and suggests that its therapeutic benefits may vary based on the disease context. Furthermore, changes in haematological parameters support existing literature linking elevated haemoglobin and platelet activation to PAH, emphasizing the need for careful monitoring of these parameters in clinical settings.
Conclusion: The combination of CBD and Selexipag demonstrates enhanced therapeutic potential for PAH compared to monotherapy, with promising improvements in key biomarkers. Nevertheless, the paradoxical increase in TNF-α and associated haematological changes necessitate further research to elucidate the mechanisms behind CBD’s effects and optimize therapeutic strategies for PAH. Future studies should focus on understanding these complex interactions and exploring the full therapeutic potential of CBD and Selexipag in cardiovascular disease management.
Keywords: Pulmonary Arterial Hypertension, Cannabidiol, Selexipag, Brain Natriuretic Peptide, Total antioxidant capacity, Tumour Necrosis Factor Alpha, Monocrotaline, Platelet count, Haemoglobin levels
Carbapenem-resistant enterobacterales at a quaternary public hospital in Durban, KwaZulu-Natal: Ascertaining the clinical and molecular paradigm shift following COVID-19.
(2025) Brijlal, Nitesh.; Swe Swe-Han, Khine.; Maphumulo, Sandra Lihle.
Extensive carbapenem use has resulted in an increasing occurrence of difficult-to-treat resistant gram-negative bacteria (DTR-GNB), such as carbapenem-resistant Enterobacterales (CREs). The international antimicrobial resistance (AMR) landscape was profoundly impacted due to varying antibiotic prescribing practices following coronavirus disease 2019 (COVID-19). The resultant evolution in multidrug-resistant organism (MDRO) trends underscored this novel study’s aim in establishing the COVID-19 pandemic’s influence on the prevalence, molecular characterisation, and clinical outcome of CRE infections at a South African quaternary public hospital.
Methods
Demographics, microorganism identification, antibiograms, and patient outcomes with associated factors were extracted retrospectively from electronic records at Inkosi Albert Luthuli Central Hospital (IALCH). Carbapenemase-encoding genes from CRE isolates were prospectively identified by conventional multiplex polymerase chain reaction. Comparisons between the pre-COVID-19 (01 January 2018 to 05 March 2020) and post-COVID-19 (06 March 2020 to 31 May 2023) periods were conducted.
Results
A total of 1481 (n) CRE samples were analysed from 985 patients, with an age range of 2 days to 91-years-old. The post-COVID-19 CRE prevalence (13.58%) was more than double the prepandemic prevalence (6.72%). Klebsiella pneumoniae (85.7%; 1269/1481) was the predominant microbial species, followed by Enterobacter cloacae (6.4%; 95/1481), both of which exhibited in vitro resistance to majority of antibiotic classes. Of the 357 molecularlytested isolates, 322 (90.2%) were carbapenemase-producers, with an upsurge in blaOXA-48 (20.8%; 15/72 versus 61.2%; 137/224, p < 0.001) and decrease in blaNDM (69.4%; 50/72 versus 17.9%; 40/245, p < 0.001) in Klebsiella pneumoniae relative to the COVID-19 periods. Overall, majority of deaths (42.2%; 57/135) occurred within 7 days of CRE isolation, while linear regression analysis showed that intensive/high-care unit admission and sterile site infection were significantly associated Conclusion
There is a rising CRE burden and shift in carbapenemase-encoding gene prevalence within this referral healthcare institution following COVID-19. This study highlights the need for ongoing epidemiological surveillance and suggests conducting routine carbapenemase testing for CRE infections amongst selected patients. Multisectoral collaborative approaches streamlining accessibility to the newer β-lactam/β-lactamase inhibitor (BL/BLI) drug combinations, such as ceftazidime-avibactam, including agents like aztreonam and cefiderocol, are urgently required to provide directed therapy, thereby potentially improving patient clinical outcomes. ith increased all-cause mortality.
Investigating the biomarker potential of circulating small extracellular vesicles in patients presenting with sepsis.
(2024) Bhagwan-Valjee, Roushka.; Mackraj, Irene.
Sepsis is defined as an inflammatory disorder caused by a dysregulated immune response to infection, affecting approximately 48.9 million people globally. The complex and multifaceted pathophysiology of sepsis complicates clinical diagnosis, management and treatment. Without a validated gold standard for diagnosis, definitive biomarkers are critical. Recently, small extracellular vesicles (sEVs) and exosomes1 have emerged as promising biomarkers of disease, owing to their role in intercellular communication. Therefore, the present study has evaluated the use of sEVs as possible biomarkers for sepsis. The approach included providing a theoretical framework surrounding sEVs, their role in sepsis pathophysiology and the potential these sEVs have as diagnostic, prognostic and therapeutic tools for sepsis. This led to the evaluation of commonly used surface markers for identifying extracellular vesicles using a multi-level, automated and precise platform. We identified an abundance of CD63, CD81 and CD9 positive particles in sepsis patients. Interestingly, the data provided distinct colocalization patterns which are abundant in sepsis patients. Our study highlighted that the CD63/CD9 colocalization may be of increasing interest in exploring the potential of these vesicles as biomarkers for sepsis. Furthermore, developing biomarkers for sepsis has become increasingly difficult due to the presence of co-morbidities. These co-morbidities further complicate the pathophysiology of sepsis, increasing the mortality rate and the risk of developing organ failure. Additionally, previous studies confirm a vast array of surface markers on the membrane of sEVs. These markers have roles in protein-protein interactions and target cell signalling. We then, further investigated the surface marker profiles in 4 cohorts (viz. healthy controls, hypertension, sepsis patients with no pre-existing co-morbidities and sepsis patients with previously diagnosed hypertension). In doing so, we identified specific surface marker profiles of sepsis and hypertension when compared to healthy controls or the other pathological states. These surface marker profiles could aid in the further understanding of sepsis pathophysiology and the role sEVs play therein. This study highlights that sEVs and the identified surface marker profiles could be exploited in the interest of biomarker development for sepsis.