Hookworm Infections and Sociodemographic Factors Associated With Female Reproductive Tract Infections in Rural Areas of the Central Region of Togo

Exploring microRNA-Mediated Immune Responses to Soil-Transmitted Helminth and Herpes Simplex Virus Type 2 Co-Infections

Over the last two decades, the field of microRNA (miRNA) research has grown significantly. MiRNAs are a class of short, single-stranded, non-coding RNAs that regulate gene expression post-transcriptionally. Thereby, miRNAs regulate various essential biological processes including immunity. Dysregulated miRNAs are associated with various infectious and non-infectious diseases. Recently co-infection with soil-transmitted helminths (STHs) and herpes simplex virus type 2 (HSV-2) has become a focus of study. Both pathogens can profoundly influence host immunity, particularly in under-resourced and co-endemic regions. It is well known that STHs induce immunomodulatory responses that have bystander effects on unrelated conditions. Typically, STHs induce T-helper 2 (Th2) and immunomodulatory responses, which may dampen the proinflammatory T-helper 1 (Th1) immune responses triggered by HSV-2. However, the extent to which STH co-infection influences the host immune response to HSV-2 is not well understood. Moreover, little is known about how miRNAs shape the immune response to STH/HSV-2 co-infection. In this article, we explore the potential influence that STH co-infection may have on host immunity to HSV-2. Because STH and HSV-2 infections are widespread and disproportionately affect vulnerable and impoverished countries, it is important to consider how STHs may impact HSV-2 immunity. Specifically, we explore how miRNAs contribute to both helminth and HSV-2 infections and discuss how miRNAs may mediate STH/HSV-2 co-infections. Insight into miRNA-mediated immune responses may further improve our understanding of the potential impact of STH/HSV-2 co-infections.

Potential Interactions Between Soil-Transmitted Helminths and Herpes Simplex Virus Type II: Implications for Sexual and Reproductive Health in Sub-Saharan African

Sub-Saharan Africa (SSA) bears a disproportionate and overlapping burden of soil-transmitted helminths (STHs) and sexually transmitted viral infections. An estimated 232 million pre-school and school-aged children in SSA are vulnerable to STH infections. Together with this, SSA has a high prevalence of herpes simplex virus type II (HSV-2), the primary cause of genital herpes. Studies have examined the immunological interactions between STHs and human immunodeficiency virus and human papillomavirus during co-infections. However, epidemiological and immunological studies on STH-HSV-2 co-infections are lacking, therefore their impact on sexual and reproductive health is not fully understood. STH-driven Th2 immune responses are known to downregulate Th1/Th17 immune responses. Therefore, during STH-HSV-2 co-infections, STH-driven immune responses may alter host immunity to HSV-2 and HSV-2 pathology. Herein, we provide an overview of the burden of STH and HSV-2 infections in SSA, and host immune responses to STH and HSV-2 infections. Further, we emphasize the relevance and urgent need for (i) focused research into the interactions between these important pathogens, and (ii) integrated approaches to improve the clinical detection and management of STH-HSV-2 co-infections in SSA.

Herpes simplex virus type 2 in sub-Saharan Africa and the potential impact of helminth immune modulation

Herpes simplex virus type 2 (HSV-2) and helminth infections are among the most widespread infectious diseases in sub-Saharan Africa (SSA). Helminths are known to modulate host immune responses and consequently impact the severity and outcomes of unrelated diseases, including allergies, autoimmune conditions, and infectious diseases. In this way, helminths may modulate essential immune responses against HSV-2 during co-infection and may alter susceptibility to and pathology of HSV-2. However, the epidemiology of STH/HSV-2 co-infections is understudied, and whether helminths influence the host immune response to HSV-2 is not well understood. In this perspective piece, we briefly examine the current knowledge on helminth immune modulation of important pathogens that are endemic to SSA, arguing that it is important to explore HSV-2 and helminth co-infections to elucidate potential interactions between HSV-2 and helminths. This is particularly relevant in SSA, where both pathogens are highly prevalent.

Infection with soil-transmitted helminths and their impact on coinfections

The most important soil-transmitted helminths (STHs) affecting humans are roundworms, whipworms, and hookworms, with a large proportion of the world's population infected with one or more of these intestinal parasites. On top of that, concurrent infections with several viruses, bacteria, protozoa, and other helminths such as trematodes are common in STH-endemic areas. STHs are potent immunomodulators, but knowledge about the effects of STH infection on the direction and extent of coinfections with other pathogens and vice versa is incomplete. By focusing on Kenya, a country where STH infections in humans are widespread, we provide an exemplary overview of the current prevalence of STH and co-occurring infections (e.g. with Human Immunodeficiency Virus, Plasmodium falciparum, Giardia duodenalis and Schistosoma mansoni). Using human data and complemented by experimental studies, we outline the immunomechanistic interactions of coinfections in both acutely STH transmigrated and chronically infected tissues, also highlighting their systemic nature. Depending on the coinfecting pathogen and immunological readout, STH infection may restrain, support, or even override the immune response to another pathogen. Furthermore, the timing of the particular infection and host susceptibility are decisive for the immunopathological consequences. Some examples demonstrated positive outcomes of STH coinfections, where the systemic effects of these helminths mitigate the damage caused by other pathogens. Nevertheless, the data available to date are rather unbalanced, as only a few studies have considered the effects of coinfection on the worm's life cycle and associated host immunity. These interactions are complex and depend largely on the context and biology of the coinfection, which can act in either direction, both to the benefit and detriment of the infected host.

Filariasis research - from basic research to drug development and novel diagnostics, over a decade of research at the Institute for Medical Microbiology, Immunology and Parasitology, Bonn, Germany

Filariae are vector borne parasitic nematodes, endemic in tropical and subtropical regions causing avoidable infections ranging from asymptomatic to stigmatizing and disfiguring disease. The filarial species that are the major focus of our institution's research are Onchocerca volvulus causing onchocerciasis (river blindness), Wuchereria bancrofti and Brugia spp. causing lymphatic filariasis (elephantiasis), Loa loa causing loiasis (African eye worm), and Mansonella spp causing mansonellosis. This paper aims to showcase the contribution of our institution and our collaborating partners to filarial research and covers decades of long research spanning basic research using the Litomosoides sigmodontis animal model to development of drugs and novel diagnostics. Research with the L. sigmodontis model has been extensively useful in elucidating protective immune responses against filariae as well as in identifying the mechanisms of filarial immunomodulation during metabolic, autoimmune and infectious diseases. The institute for Medical Microbiology, Immunology and Parasitology (IMMIP), University Hospital Bonn (UKB), Bonn, Germany has also been actively involved in translational research in contributing to the identification of new drug targets and pre-clinical drug research with successful and ongoing partnership with sub-Saharan Africa, mainly Ghana (the Kumasi Centre for Collaborative Research (KCCR)), Cameroon (University of Buea (UB)) and Togo (Laboratoire de Microbiologie et de Contrôle de Qualité des Denrées Alimentaires (LAMICODA)), Asia and industry partners. Further, in the direction of developing novel diagnostics that are sensitive, time, and labour saving, we have developed sensitive qPCRs as well as LAMP assays and are currently working on artificial intelligence based histology analysis for onchocerciasis. The article also highlights our ongoing research and the need for novel animal models and new drug targets.

Ureaplasma urealyticum induces polymorphonuclear elastase to change semen properties and reduce sperm motility: a prospective observational study

Objective

To elucidate the mechanism underlying how Ureaplasma urealyticum (UU) affects sperm quality and identify a therapeutic target.

Methods

In this prospective observational study, the differences in and relationships among semen volume, pH, viscosity, liquefaction time, sperm concentration, sperm motility [progressive motility (PR)], and seminal polymorphonuclear (PMN) elastase were analyzed in 198 normal semen samples (control group) and 198 UU-infected semen samples (observation group). The UU-infected samples were treated and the above parameters were compared between the two groups.

Results

The semen volume, viscosity, liquefaction time, and seminal PMN elastase were significantly higher in the observation than control group, but the pH and PR were significantly lower. In the observation group, the pH and PR were significantly higher after than before treatment, whereas the semen volume, PMN elastase, viscosity, and liquefaction time were lower. UU was closely related to semen volume, pH, viscosity, liquefaction time, sperm motility (PR), and PMN elastase. PMN elastase had significant negative effects on semen pH and sperm motility (PR) but positive effects on viscosity and liquefaction time.

Conclusion

UU might induce PMN elastase to increase the liquefaction time and viscosity of semen, eventually decreasing PR. PMN elastase might be a therapeutic target of UU.