The development of oxidative stress depends on the deregulation of the fine balance between the proportion of reactive oxygen species (ROS) generation and the activity of antioxidants. As oxidative stress is deleterious for Leishmania sp., their host cell generates ROS as one of the foremost defence strategies. The parasites have also raised a variety of counteracting tricks in order to conquer this challenge. Upon infection, the host’s own antioxidant system is activated by the parasite to neutralise the oxidative stress-mediated protection. In addition to using the host’s antioxidant mechanisms, some genes within the parasite also make them more tolerant against oxidative stress. Therefore, the present review focuses on some major regulators intimately related to the equilibrium between oxidation and antioxidation following infection with Leishmania sp., which may be helpful in developing a comprehensive knowledge of this specific wing of infection biology associated with oxidative stress.

Reactive oxygen species (ROS) play a dual role in leishmaniasis by contributing to both host defence and parasite survival mechanisms. In the host, ROS promote parasite clearance through induction of apoptosis, activation of pro-inflammatory signalling pathways (e.g., MAPK, JNK), inflammasome assembly, and M1 macrophage polarisation. Conversely, Leishmania species have evolved multiple strategies to neutralize ROS, including the upregulation of host antioxidant enzymes like HO-1, inhibition of ROS-producing pathways, and expression of parasite-derived antioxidants such as SOD, GPx, and trypanothione reductase. The parasite alsoadapts through gene regulation and metabolic changes to counter oxidative stress. Importantly, ROS have emerged as key targets for antileishmanial therapies, with various drugs and natural compounds shown to induce ROS-mediated parasite death, highlighting their potential in future therapeutic development.

In summary, the survival of Leishmania hinges on its ability to counteract host-induced oxidative stress. Targeting its antioxidant defences and enhancing host ROS production can disrupt this balance, leading to parasite death. Exploring ROS-related signalling offers a promising path for developing effective therapies against leishmaniasis.

In this short narrative review, we would like to discuss the immunomodulatory effects of South African geranium (Pelargonium sidoides) root extract EPs7630 in treating acute rhinosinusitis. The plant has been used for centuries to treat respiratory tract inflammation, such as sinusitis, pharyngitis and bronchitis. South African geranium is rich in polyphenols, flavonoids, tannins, diterpenes and proanthocyanidins, but the main constituent is a type of coumarin called ‘umckalin’ (6–hydroxy–5,5–dimethoxy–coumarin). The substance is standardised as an aqueous-ethanolic extract from the root of this plant under the code name EPs7630.

The article presents the results of in vitro and in vivo studies of administering this herbal drug in acute viral, post-viral and bacterial rhinosinusitis. The focus is on the immunomodulatory effects of EPs7630 during the therapy of this acute inflammation of the nasal mucosa.

According to the results of some studies, EPs7630 stimulates monocyte-dependent activity and inhibits neutrophil-dependent chemokine activity. However, given the small number of studies, the level of evidence is low, implying the need for new research.

Particular attention should be paid to the effect of EPs7630 on bradykinin, the mediator that triggers most inflammatory processes in acute rhinosinusitis.

Tumour immunotherapy holds great promise as a treatment for cancer, which ranks as the second highest cause of mortality worldwide. This therapeutic approach can be broadly categorized into two main types: active immunotherapy and passive or adoptive immunotherapy. Active immunotherapy, such as cancer vaccines, stimulates the patients’ immune system to target tumour cells. On the other hand, adoptive immunotherapy involves supplying in vitro activated immune cells, such as T cells, natural killer cells and macrophages, to the patient to combat the tumour. Induced pluripotent stem cells are extensively utilized in both active and adoptive tumour immunotherapy due to their pluripotency and ease of gene editing. They can be differentiated into various types of immune cells for direct cancer treatment and can also function as tumour vaccines to elicit an immune response against the tumour. Importantly, iPSCs can be leveraged to develop off-the-shelf allogenic immunotherapy products.

This article provides a comprehensive review of the application of iPSCs in tumor immunotherapy, along with a discussion of the opportunities and challenges in this evolving field.