Suraj P Parihar

• PhD
• Professor (Associate) at University of Cape Town

Tuberculosis remains one of the major global health challenges with those previously exposed presenting persisting pulmonary dysfunction. Therefore, improved control measures are still required to prevent or reduce the TB-induced immunopathology in affected individuals. Host directed therapies that target host factors, have been suggested to improv...

Introduction Forkhead box P3 (Foxp3) T regulatory cells are critical for maintaining self-tolerance, immune homeostasis, and regulating the immune system. Methods We investigated interleukin-4 receptor alpha (IL-4Rα) signalling on T regulatory cells (Tregs) during Listeria monocytogenes (L. monocytogenes) infection using a mouse model on a BALB/c...

Formyl peptide receptors (FPR), part of the G-protein coupled receptor superfamily, are pivotal in directing phagocyte migration towards chemotactic signals from bacteria and host tissues. Although their roles in acute bacterial infections are well-documented, their involvement in immunity against tuberculosis (TB) remains unexplored. Here, we inve...

Mycobacterium tuberculosis (Mtb) infection induces a marked influx of neutrophils into the lungs, which intensifies the severity of tuberculosis (TB). The metabolic state of neutrophils significantly influences their functional response during inflammation and interaction with bacterial pathogens. However, the effect of Mtb infection on neutrophil...

Formyl peptide receptors (FPR), part of the G-protein coupled receptor superfamily, are pivotal in directing phagocyte migration towards chemotactic signals from bacteria and host tissues. Although their roles in acute bacterial infections are well-documented, their involvement in immunity against tuberculosis (TB) remains unexplored. This study in...

Atherosclerosis is a chronic inflammatory disease in which fats, lipids, cholesterol, calcium, proliferating smooth muscle cells, and immune cells accumulate in the intima of the large arteries, forming atherosclerotic plaques. A complex interplay of various vascular and immune cells takes place during the initiation and progression of atherosclero...

Medicinal plants have been with mankind since their existence on Earth. Till date, the prior art is filled with the use and significance of a repertoire of a variety of medicinal plants from different geographical regions around the world. Building immunity was a miscellaneous priority for us all till the COVID-19 pandemic hit the world. In the las...

Colorectal cancer is one of the leading causes of death worldwide. Its incidence and mortality have significantly increased during the past few years. Colorectal cancer cells cross-talk with other cells through exosomes in their tumor microenvironment. The miRNAs containing exosomes are responsible for tumor growth, invasion, and metastasis. Multip...

Host inflammatory responses are key to protection against injury; however, persistent inflammation is detrimental and contributes to morbidity and mortality. Herein, we demonstrated the anti-inflammatory role of Arteannuin-B (1) and its new spirocyclic-2-isoxazoline derivative JR-9 and their side effects in acute inflammatory condition in vivo usin...

Introduction PKCδ is ubiquitously expressed in mammalian cells and its dysregulation plays a key role in the onset of several incurable diseases and metabolic disorders. However, much remains unknown about the metabolic pathways and disturbances induced by PKC deficiency, as well as the metabolic mechanisms involved. Objectives This study aims to...

Lymphoblastic leukemia 1 (Lyl1) is a well-studied transcription factor known to exhibit oncogenic potential in various forms of leukemia with pivotal roles in hematopoietic stem cell biology. While its role in early hematopoiesis is well established, its function in mature innate cells is less explored. Here, we identified Lyl1 as a drastically per...

Amongst the most significant scientific findings in the last two decades has been the role of inflammatory processes in protecting the host against the causative agents of injury. In this work, we examined the anti-inflammatory activities of Arteannuin-B (1) and its novel spirocyclic-2-isoxazoline derivative ( 2 ). Various anti-inflammatory assays...

The arid and semi-arid regions of Rajasthan are one of the most extreme biomes of India, possessing diverse microbial communities that exhibit immense biotechnological potential for industries. Herein, we sampled study sites from arid and semi-arid regions of Thar Desert, Rajasthan, India and subjected them to chemical, physical and metagenomics an...

Advanced computational tools focusing on protein-protein interaction (PPI) based drug development is a powerful platform to accelerate the therapeutic development of small lead molecules and repurposed drugs. Toll/interleukin-1 receptor (TIR) domain-containing adapter protein (TIRAP) and its interactions with other proteins in macrophages signallin...

Background Interleukin-4-induced gene 1 (IL-4i1) encodes L-phenylalanine oxidase that catabolizes phenylalanine into phenylpyruvate. IL-4i1 is mainly expressed by antigen-presenting cells, inhibits T-cell proliferation, regulates B-cell activation, drives macrophage polarization and modulates Th1 inflammatory immune responses, but its role in bacte...

Globally, more than 10 million people developed active tuberculosis (TB), with 1.4 million deaths in 2020. In addition, the emergence of drug-resistant strains in many regions of the world threatens national TB control programs. This requires an understanding of host-pathogen interactions and finding novel treatments including host-directed therapi...

Tuberculosis (TB) is the global health problem with the second highest number of deaths from a communicable disease after COVID-19. Although TB is curable, poor health infrastructure, long and grueling TB treatments have led to the spread of TB pandemic with alarmingly increasing multidrug-resistant (MDR)-TB prevalence. Alternative host modulating...

Some vulnerable population groups at risk for tuberculosis (TB) may have a low n-3 polyunsaturated fatty acid (PUFA) status. Our research previously showed that adjunct n-3 LCPUFA in TB are beneficial in n-3 PUFA sufficient C3HeB/FeJ mice. Here we investigated the effect of adjunct n-3 LCPUFA supplementation to TB-mice with a low, compared to a suf...

In tuberculosis, T cell-mediated immunity is extensively studied whilst B cells received limited attention in human and mice. Of interest, Mycobacterium tuberculosis (Mtb) does increase IL-4 Receptor-alpha (IL4Rα) expression in murine B cells. To better understand the role of IL4Rα signalling in B cells, we compared wild type mice with B cell-speci...

Using the Cap Analysis of Gene Expression (CAGE) technology, the FANTOM5 consortium provided one of the most comprehensive maps of transcription start sites (TSSs) in several species. Strikingly, ~72% of them could not be assigned to a specific gene and initiate at unconventional regions, outside promoters or enhancers. Here, we probe these unassig...

Intakes of the omega-3 essential fatty acids (n-3 EFAs) are low in the general adult population, with high n-6/n-3 polyunsaturated fatty acid (PUFA) ratios and the accompanying suboptimal n-3 PUFA status. Eicosapentaenoic (EPA) and docosahexaenoic acid (DHA) have antibacterial and inflammation-resolving effects in tuberculosis (TB). However, whethe...

Advancement in the understanding of inflammation regulation during tuberculosis (TB) treatment has led to novel therapeutic approaches being proposed. The use of immune mediators like anti-inflammatory and pro-resolving molecules for such, merits attention. Drug repurposing is a widely used strategy that seeks to identify new targets to treat or ma...

Non-resolving inflammation is characteristic of tuberculosis (TB). Given their inflammation-resolving properties, omega-3 long-chain polyunsaturated fatty acids (n-3 LCPUFA) may support TB treatment. This research aimed to investigate the effects of n-3 LCPUFA on clinical and inflammatory outcomes of Mycobacterium tuberculosis ( Mtb )-infected C3He...

Atherosclerosis (AS) is a widespread pathological coronary heart disease (CHD), which, along with other cardiovascular diseases (CVDs), is the primary cause of global mortality. It is initiated by the accumulation of cholesterol-laden macrophages in the artery wall, thereby forming the foam-cells, the hallmark of AS. Increased influx of oxidized LD...

Progressive inflammation and anemia are common in tuberculosis (TB) and linked to poor clinical outcomes. Eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA) have inflammation-resolving properties, whereas iron supplementation in TB may have limited efficacy and enhance bacterial growth. We investigated effects of iron and EPA/DHA supplement...

Tuberculosis (TB), caused by the highly infectious Mycobacterium tuberculosis, remains a leading cause of death worldwide, with an estimated 1.6 million associated deaths reported in 2017. In South Africa, an estimated 322,000 (range 230,000-428,000) people were infected with TB in 2017, and a quarter of them lost their lives due to the disease. Ba...

Tuberculosis (TB), caused by the highly infectious Mycobacterium tuberculosis , remains a leading cause of death worldwide, with an estimated 1.6 million associated deaths reported in 2017. In South Africa, an estimated 322,000 (range 230,000-428,000) people were infected with TB in 2017, and a quarter of them lost their lives due to the disease. B...

Tuberculosis (TB), caused by the highly infectious Mycobacteriumtuberculosis , remains a leading cause of death worldwide, with an estimated 1.6 million associated deaths reported in 2017. In South Africa, an estimated 322,000 (range 230,000-428,000) people were infected with TB in 2017, and a quarter of them lost their lives due to the disease. Ba...

Tuberculosis (TB), caused by the highly infectious Mycobacteriumtuberculosis , remains a leading cause of death worldwide, with an estimated 1.6 million associated deaths reported in 2017. In South Africa, an estimated 322,000 people were infected with TB in 2017, and a quarter of them lost their lives due to the disease. Bacille Calmette-Guérin (B...

Tuberculosis, caused by the highly infectious Mycobacteriumtuberculosis , remains a leading cause of death worldwide, with an estimated 1.6 million associated deaths reported in 2017. In South Africa, an estimated 322,000 people were infected with TB in 2017, and a quarter of them lost their lives due to the disease. Bacille Calmette-Guérin remains...

Tuberculosis, caused by the highly infectious Mycobacterium tuberculosis, remains a leading cause of death worldwide, with an estimated 1.6 million associated deaths reported in 2017. In South Africa, an estimated 322,000 people were infected with TB in 2017, and a quarter of them lost their lives due to the disease. Bacille Calmette-Guérin remains...

Basic leucine zipper transcription factor 2 (Batf2) activation is detrimental in Type 1-controlled infectious diseases, demonstrated during infection with Mycobacterium tuberculosis (Mtb) and Listeria monocytogenes Lm. In Batf2-deficient mice (Batf2−/−), infected with Mtb or Lm, mice survived and displayed reduced tissue pathology compared to infec...

Statins were first identified over 40 years ago as lipid-lowering drugs and have been remarkably effective in treating cardiovascular diseases. As research advanced, the protective effects of statins were additionally attributed to their anti-inflammatory, antioxidative, anti-thrombotic and immunomodulatory functions rather than lipid-lowering abil...

Different animal models have been used to understand mechanisms of Tuberculosis (TB) and test TB drugs. Mice, guinea pigs and non-human primates have been found particularly useful. The C3HeB/FeJ mouse, specifically, is an excellent TB model and has been deemed the most cost-effective and sophisticated animal model in which the immune response is v...

An emerging realization of infectious disease is that pathogens can cause a high incidence of genetic instability within the host as a result of infection-induced DNA lesions. These often lead to classical hallmarks of cancer, one of which is the ability to evade apoptosis despite the presence of numerous genetic mutations that should be otherwise...

Nutlin3a confirms pivotal role of hnRNP-K in apoptosis evasion by HIV-1. (A) Exogenous lincRNA-p21 (full-length or truncated) expression alone does not lead to nuclear hnRNP-K in the presence of HIV-1 in Ghost(3) cells. (B) Exogenous lincRNA-p21 (full-length or truncated) expression and Nutlin3a treatment do not lead to apoptosis in Ghost(3) cells....

HIV-1 manipulates lincRNA-p21's protein binding partners. (A) Untreated Ghost(3) cells show nuclear HuR over a 48 h time course by immunofluorescence staining. (B) HuR expression is significantly decreased as measured by quantitative real–time RT–PCR analysis following 48 h of exposure to siHuR in Ghost(3) cells (mean ± SE of 3 biological replicate...

HIV-1 masks DNA damage, protects against additional lethal DNA damage, and prevents lincRNA-p21 upregulation. (A) HIV-1 integration occurs approximately 16 h post-infection of Ghost(3) reporter cells and Tat-mediated activation of an integrated LTR-driven GFP reporter can be detected approximately 48 h post-infection. (B) Ghost(3) cells support HIV...

HIV-1 requires gp120 Env and MAP2K1/ERK2 to ensure hnRNP-K's cytoplasmic localization. (A) Quantitative real-time RT-PCR analysis of MAP2K1 expression relative to HPRT housekeeping gene in MAP2K1 inhibitor-treated (MPK inh.), or ERK2 inhibitor-treated (ERK inh.), or Doxorubicin-treated (+Doxo.) Ghost(3) cells normalized to untreated cells (mean ± S...

Mycobacterium tuberculosis (Mtb) infection reveals complex and dynamic host-pathogen interactions, leading to host protection or pathogenesis. Using a unique transcriptome technology (CAGE), we investigated the promoter-based transcriptional landscape of IFNγ (M1) or IL-4/IL-13 (M2) stimulated macrophages during Mtb infection in a time-kinetic mann...

This corrects the article DOI: 10.1038/mi.2017.68.

Objectives: The slow development of major advances in drug discovery for the treatment of Mycobacterium tuberculosis ( Mtb ) infection suggests a compelling need for evaluation of more effective drug therapies against TB. New classes of drugs are constantly being evaluated for anti-mycobacterial activity with currently a very limited number of new...

Significance Cutaneous leishmaniasis and schistosomiasis are neglected tropical diseases for which there are no effective vaccines and limited treatment strategies. To develop vaccine and therapeutic alternatives, a detailed understanding of host immunity is essential. We show a role for IL-4Rα–responsive B cells in host susceptibility to Leishmani...

We previously demonstrated that protein kinase C-δ (PKCδ) is critical for immunity against Listeria monocytogenes, Leishmania major, and Candida albicans infection in mice. However, the functional relevance of PKCδ during Mycobacterium tuberculosis (Mtb) infection is unknown. PKCδ was significantly upregulated in whole blood of patients with active...

An emerging realisation of infectious disease is the high incidence of genetic instability resulting from pathogen-induced DNA lesions, often leading to classical hallmarks of cancer such as evasion of apoptosis. The Human Immunodeficiency Virus type 1 (HIV-1) induces apoptosis in CD4+ T cells but is largely non-cytopathic in macrophages, thereby l...

We recently demonstrated that statins mediate protection against intracellular pathogens, Mycobacterium tuberculosis and Listeria monocytogenes in mice. Here, we investigated the immunomodulatory potential of simvastatin as a topical or systemic host-directed drug therapy in controlling inflammatory responses in an experimental mouse model of cutan...

Classically or alternatively activated macrophages (M1 and M2, respectively) play distinct and important roles for microbiocidal activity, regulation of inflammation and tissue homeostasis. Despite this, their transcriptional regulatory dynamics are poorly understood. Using promoter-level expression profiling by non-biased deepCAGE we have studied...

Basic leucine zipper transcription factor Batf2 is poorly described, whereas Batf and Batf3 have been shown to play essential roles in dendritic cell, T cell, and B cell development and regulation. Batf2 was drastically induced in IFN-γ-activated classical macrophages (M1) compared with unstimulated or IL-4-activated alternative macrophages (M2). B...

Background A meta-analysis of published data was conducted to investigate the overall risks of hypertension and QTc prolongation in patients with advanced non-small cell lung cancer (NSCLC) who were receiving vandetanib. Methods A computerized search through electronic databases, including PubMed and Embase (until Dec 2014), was performed to obtain...

Background: Statins are cholesterol-lowering drugs, targeting HMG-CoA reductase, thereby reducing the risk of coronary disorders and hypercholesterolemia. However, they also can influence immunologic responses. Methods: Peripheral blood mononuclear cells (PBMCs) and monocyte-derived macrophages (MDMs) were isolated from patients with familial hy...

In BALB/c mice, susceptibility to infection with the intracellular parasite Leishmania major is driven largely by the development of T helper 2 (Th2) responses and the production of interleukin (IL)-4 and IL-13, which share a common receptor subunit, the IL-4 receptor alpha chain (IL-4Rα). While IL-4 is the main inducer of Th2 responses, paradoxica...

Statins are well-known cholesterol lowering drugs targeting HMG-CoA-reductase, reducing the risk of coronary disorders and hypercholesterolemia. Statins are also involved in immunomodulation, which might influence the outcome of bacterial infection. Hence, a possible effect of statin treatment on Listeriosis was explored in mice. Statin treatment p...

Nematode secreted haemoglobins have unusually high affinity for oxygen and possess nitric oxide deoxygenase, and catalase activity thought to be important in protection against host immune responses to infection. In this study, we generated a monoclonal antibody (48Eg) against haemoglobin of the nematode Anisakis pegreffii, and aimed to characteriz...

The protein kinase C (PKC) family is involved in the regulation of many intracellular signalling pathways. Here, we report that the PKCδ isoform regulates IL-12p40/p70 production in macrophages and DC and that PKCδ deficiency in mice transforms the 129/Sv healer to a non-healer strain during cutaneous leishmaniasis. Leishmania major-infected PKCδ(-...

IL-1α and IL-1β are potent inflammatory cytokines and important mediators of immune responses to intracellular pathogens such as Mycobacterium tuberculosis (Mtb). Here, we investigated the role of IL-1α and IL-1β during chronic Mtb infection and spontaneous reactivation in mice. For long-term neutralization of IL-1α, IL-1β or both, mice were immuni...

Human papillomavirus (HPV) is small, double-stranded DNA virus that infects mucosal and cutaneous epithelial tissue. HPV is sexually transmitted and the viral DNA replicates extrachromosomally. The virus is non-enveloped and has an icosahedral capsid. There are approximately 118 types of HPV, which are characterized as high-risk or low- risk types....