Transmission of psoriasis by allogeneic bone marrow transplantation and blood transfusion

Stem cell therapy as a potential treatment option for psoriasis: a review

Psoriasis is a chronic inflammatory dermatological disorder characterized by white scales and clearly demarcated erythematous plaques. The prevalence of psoriasis varies from country to country and can occur at any age, implying that ethnicity, environmental factors, and genetic background all play a role in its onset. According to the World Psoriasis Day Consortium, 125 million people globally and 2%–3% of the overall community have psoriasis. The introduction of biological treatments has revolutionized the treatment of moderate to severe psoriasis. These novel drugs, particularly those targeting interleukin (IL)-17 and IL-23p19, can help most patients with psoriasis achieve clear or virtually clear skin with satisfactory durability. Nevertheless, none of these modern treatments are not entirely remedial in their current form, and alarmingly, a limited but growing proportion of patients with severe psoriasis are not responding satisfactorily to currently available treatments. Stem cell therapy, including regulatory T-cells, hematopoietic stem cell transplantation, and mesenchymal stromal cells, has been used in patients with recalcitrant psoriasis. This review discusses the stem cell treatments available for psoriasis.

Heightened splenic and bone marrow uptake of 18F-FDG PET/CT is associated with systemic inflammation and subclinical atherosclerosis by CCTA in psoriasis: An observational study

BACKGROUND AND AIMS

Psoriasis is an immune-mediated inflammatory disease with increased risk of myocardial infarction. Preclinical studies in psoriasis models show an association between chronic inflammation and immune cell proliferation in the spleen and bone marrow (BM). We sought to test the hypothesis that splenic and BM ¹⁸F-fluorodeoxyglucose (¹⁸F-FDG) uptake is heightened in psoriasis and that higher uptake associates with systemic inflammation and subclinical atherosclerotic disease measures in this cohort.

METHODS

Multimodality imaging and biomarker assays were performed in 240 participants (210 with psoriasis and 30 healthy). Splenic and BM uptake was obtained using ¹⁸F-FDG positron emission tomography/computed tomography (PET/CT). Coronary artery plaque characteristics including non-calcified burden (NCB) and lipid rich necrotic core (LRNC) were quantified using a dedicated software for CT angiography. All analyses were performed with StataIC 16 (Stata Corp., College Station, TX, USA).

RESULTS

Splenic and BM ¹⁸F-FDG uptake was increased in psoriasis (vs. healthy volunteers) and significantly associated with proatherogenic lipids, immune cells and systemic inflammation. Higher splenic ¹⁸F-FDG uptake associated with higher total coronary burden (β = 0.37; p<0.001), NCB (β = 0.39; p<0.001), and LRNC (β = 0.32; p<0.001) in fully adjusted models. Similar associations were seen for BM ¹⁸F-FDG uptake in adjusted models (β = 0.38; β = 0.41; β = 0.24; respectively, all p<0.001).

CONCLUSIONS

Heightened splenic and BM uptake of ¹⁸F-FDG is associated with proatherogenic lipids, immune cells, inflammatory markers and coronary artery disease. These findings provide insights into atherogenic mechanisms in psoriasis and suggest that immune cell proliferation in the spleen and BM is associated with subclinical atherosclerosis.

Stem cell therapy in dermatology

Stem cells are precursor cells present in many tissues with ability to differentiate into various types of cells. This interesting property of plasticity can have therapeutic implications and there has been substantial research in this field in last few decades. As a result, stem cell therapy is now used as a therapeutic modality in many conditions, and has made its way in dermatology too. Stem cells can be classified on the basis of their source and differentiating capacity. In skin, they are present in the inter-follicular epidermis, hair follicle, dermis and adipose tissue, which help in maintaining normal skin homeostasis and repair and regeneration during injury. In view of their unique properties, they have been employed in treatment of several dermatoses including systemic sclerosis, systemic lupus erythematosus, scleromyxedema, alopecia, Merkel cell carcinoma, pemphigus vulgaris, psoriasis, wound healing, epidermolysis bullosa and even aesthetic medicine, with variable success. The advent of stem cell therapy has undoubtedly brought us closer to curative treatment of disorders previously considered untreatable. Nevertheless, there are multiple lacunae which need to be addressed including ideal patient selection, timing of intervention, appropriate conditioning regimens, post-intervention care and cost effectiveness. Further research in these aspects would help optimize the results of stem cell therapy.

Unraveling the ECM-Immune Cell Crosstalk in Skin Diseases

The extracellular matrix (ECM) is a complex network of proteins and proteoglycans secreted by keratinocytes, fibroblasts and immune cells. The function of the skin ECM has expanded from being a scaffold that provides structural integrity, to a more dynamic entity that is constantly remodeled to maintain tissue homeostasis. The ECM functions as ligands for cell surface receptors such as integrins, dystroglycans, and toll-like receptors (TLRs) and regulate cellular signaling and immune cell dynamics. The ECM also acts as a sink for growth factors and cytokines, providing critical cues during epithelial morphogenesis. Dysregulation in the organization and deposition of ECMs lead to a plethora of pathophysiological conditions that are exacerbated by aberrant ECM-immune cell interactions. In this review, we focus on the interplay between ECM and immune cells in the context of skin diseases and also discuss state of the art therapies that target the key molecular players involved.

Stem Cells as Potential Candidates for Psoriasis Cell-Replacement Therapy

Recent years have seen considerable progress in explaining the mechanisms of the pathogenesis of psoriasis, with a significant role played in it by the hyper-reactivity of Th1 and Th17 cells, Treg function disorder, as well as complex relationships between immune cells, keratinocytes, and vascular endothelium. The effect of stem cells in the epidermis and stem cells on T cells has been identified and the dysfunction of various types of stem cells may be a prime cause of dysregulation of the inflammatory response in psoriasis. However, exploring these mechanisms in detail could provide a chance to develop new therapeutic strategies. In this paper, the authors reviewed data on the role played by stem cells in the pathogenesis of psoriasis and initial attempts at using them in treatment.