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Primary immunodeficiency diseases (PIDs) are a group of rare inherited disorders affecting the immune system that can be conventionally treated with allogeneic hematopoietic stem cell transplantation and with experimental autologous gene therapy. With both approaches still facing important challenges, gene editing has recently emerged as a potential valuable alternative for the treatment of genetic disorders and within a relatively short period from its initial development, has already entered some landmark clinical trials aimed at tackling several life-threatening diseases. In this review, we discuss the progress made towards the development of gene editing-based therapeutic strategies for PIDs with a special focus on Wiskott - Aldrich syndrome and outline their main challenges as well as future directions with respect to already established treatments.

Cancer is one of the leading diseases, causing deaths worldwide. Nearly 10 million deaths were reported in 2020 due to cancer alone. Several factors are involved in cancer progressions, such as lifestyle and genetic characteristics. According to a recent report, extracellular vesicles (EVs) are involved in cancer initiation, progression, and therapy failure. EVs can play a major role in intracellular communication, the maintenance of tissue homeostasis, and pathogenesis in several types of diseases. In a healthy person, EVs carry different cargoes, such as miRNA, lncRNA etc., to help other body functions. On the other hand, the same EV in a tumor microenvironment carries cargoes such as miRNA, lncRNA, etc., to initiate or help cancer progression at various stages. These stages may include the proliferation of cells and escape from apoptosis, angiogenesis, cell invasion, and metastasis, reprogramming energy metabolism, evasion of the immune response, and transfer of mutations. Tumor-derived EVs manipulate by altering normal functions of the body and affect the epigenetics of normal cells by limiting the genetic makeup through transferring mutations, histone modifications, etc. Tumor-derived EVs also pose therapy resistance through transferring drug efflux pumps and posing multiple drug resistances. Such EVs can also help as biomarkers for different cancer types and stages, which ultimately help with cancer diagnosis at early stages. In this review, we will shed light on EVs’ role in performing normal functions of the body and their position in different hallmarks of cancer, in altering the genetics of a normal cell in a tumor microenvironment, and their role in therapy resistance, as well as the importance of EVs as diagnostic tools.

Productive HIV-1 replication requires viral integrase (IN), which catalyzes integration of the viral genome into the host cell DNA. IN, however, is short lived and is rapidly degraded by the host ubiquitin-proteasome system. To identify the cellular factors responsible for HIV-1 IN degradation, we performed a targeted RNAi screen using a library of siRNAs against all components of the ubiquitin-conjugation machinery using high-content microscopy. Here we report that the E3 RING ligase TRIM33 is a major determinant of HIV-1 IN stability. CD4-positive cells with TRIM33 knock down show increased HIV-1 replication and proviral DNA formation, while those overexpressing the factor display opposite effects. Knock down of TRIM33 reverts the phenotype of an HIV-1 molecular clone carrying substitution of IN serine 57 to alanine, a mutation known to impair viral DNA integration. Thus, TRIM33 acts as a cellular factor restricting HIV-1 infection by preventing provirus formation., HIV-1 integration into host DNA is mediated by the viral integrase (IN). Here, using siRNA screen and high-content microscopy, the authors identify the host E3 RING ligase TRIM33 to affect IN stability and show that TRIM33 prevents viral integration by triggering IN proteasome-mediated degradation.

Laser therapy, recently renamed as photobiomodulation, stands as a promising supportive treatment for oral mucositis induced by oncological therapies. However, its mechanisms of action and, more importantly, its safety in cancer patients, are still unclear. Here we explored the anti-cancer effect of 3 laser protocols, set at the most commonly used wavelengths, in B16F10 melanoma and oral carcinogenesis mouse models. While laser light increased cell metabolism in cultured cells, the in vivo outcome was reduced tumor progression. This striking, unexpected result, was paralleled by the recruitment of immune cells, in particular T lymphocytes and dendritic cells, which secreted type I interferons. Laser light also reduced the number of highly angiogenic macrophages within the tumor mass and promoted vessel normalization, an emerging strategy to control tumor progression. Collectively, these results set photobiomodulation as a safety procedure in oncological patients and open the way to its innovative use for cancer therapy., Highlights • Laser light reduces tumor progression while increasing metabolism of cultured cells • Laser-treated tumors contain mature vessels and less pro-angiogenic macrophages • Tumors treated by photobiomodulation are surrounded by lymphocytes and dendritic cells • Laser light promotes secretion of type I interferons in vitro and in vivo Laser therapy, also named photobiomodulation, is recommended to heal mucositis induced by oncological treatments, raising concerns on its safe use in cancer patients. Ottaviani et al. showed that laser light inhibits tumor progression, induces tumor vessel normalization and stimulates the immune system to produce type I interferons, proving the safety and extending the use of laser-based therapies to cancer.

Serine protease inhibitors (serpins) family have a complex mechanism of inhibition that requires a large scale conformational change. Antithrombin (AT), a member of serpin superfamily serves as a key regulator of the blood coagulation cascade, deficiency of which leads to thrombosis. In recent years, a handful of studies have identified small compounds that retard serpin polymerization but abrogated the normal activity. Here, we screened small molecules to find potential leads that can reduce AT polymer formation. We identified simple sugar molecules that successfully blocked polymer formation without a significant loss of normal activity of AT under specific buffer and temperature conditions. Of these, trehalose proved to be most promising as it showed a marked decrease in the bead like polymeric structures of AT shown by electron microscopic analysis. A circular dichroism (CD) analysis indicated alteration in the secondary structure profile and an increased thermal stability of AT in the presence of trehalose. Guanidine hydrochloride (GdnHCl)-based unfolding studies of AT show the formation of a different intermediate in the presence of trehalose. A time-dependent fluorescence study using 1,1′-bi(4-anilino)naphthalene-5,5′-disulfonic acid (Bis-ANS) shows that trehalose affects the initial conformational change step in transition from native to polymer state through its binding to exposed hydrophobic residues on AT thus making AT less polymerogenic. In conclusion, trehalose holds promise by acting as an initial scaffold that can be modified to design similar compounds with polymer retarding propensity.

Endogenous proteins that promote vascular endothelial cell based inhibition of angiogenesis are an attractive option for antitumor therapy. Inactive cleaved and latent conformations of antithrombin (AT) are antiangiogenic, but not its native form which is an inhibitor of proteases involved in blood coagulation. Unlike native, the cleaved and latent conformations are reactive center loop inserted conformations which binds heparin with very low affinity. We use a sulfoxy modified AT to assess the role of reactive center loop insertion and heparin affinity in antiangiogenic function. Chorioallantoic membrane assay (CAM) shows that antiangiogenic activity of latent and oxidized AT are better than thalidomide, a potent antiangiogenic drug. Wound healing experiments suggest that latent and oxidized conformations can influence endothelial cell migration. Latent and cleaved conformations of AT shows an increase in α-helical content in the presence of unfractionated heparin, but not the oxidized AT. Unlike the loop inserted polymer, cleaved and latent conformations, oxidized AT has factor Xa inhibitory activity indicating that loop insertion is not necessary for antiangiogenic role. The results of our study establish that active conformation of AT can become antiangiogenic while maintaining its anticoagulant activity possibly through chelation of low affinity heparin in the vicinity of endothelial cell.

Endogenous angiogenesis inhibitor that specifically decreases tumor cell proliferation can be used to treat cancer since angiogenesis is required at every step of tumor progression and metastasis. Endothelial cells are the main target for the antiangiogenic therapy because they are non-transformed and easily accessible to angiogenic inhibitors. Antithrombin functions as a principal plasma protein inhibitor of blood coagulation proteinases and belongs to the family of serine protease inhibitors (serpins) which have common mechanism of inhibition. Antithrombin acquires a potent antiangiogenic activity upon conversion of the native molecule to cleaved or latent conformation. Cleaved and latent preparations of bovine and human plasma derived antithrombin inhibits capillary endothelial cell proliferation and the growth of human SK-NAS neuroblastoma and Lewis lung carcinoma tumors in mice but not the native antithrombin's. The native form of antithrombin binds with high affinity to vascular heparan sulfate proteoglycans containing a specific pentasaccharide sequence and it is this cofactor interaction that activates antithrombin to maximal rate of thrombin inhibition. Upon inhibitory complex formation with target proteinases the antithrombin undergoes stressed to relaxed transformation and lose their high affinity for pentasacchride. Low affinity relaxed conformation with reduced heparin binding like cleaved and latent are antiangiogenic but native high affinity heparin binding stressed conformation is not, indicating the critical importance of heparin affinity in antithrombin antiangiogenic function. Based on evidence of interactions of the endothelial cell growth factors bFGF (basic fibroblast growth factor) and VEGF (vascular endothelial cell growth factor) with heparin like molecule in matrix, the possibility of antiangiogenic antithrombin to interfere with endothelial cell growth and angiogenesis through heparin mediated mechanism deserves serious consideration and investigation. It is also possible that cleaved and latent conformations with reduced affinity for heparins can also induce conformational change in the antithrombin which can open an epitope on the antithrombin surface for appropriate interactions on the endothelial surface for better antiangiogenic activity. This review illustrates the potential of antithrombin and other serpin family members as endogenous antiangiogenic proteins.

Background Wiskott-Aldrich syndrome (WAS) is a rare primary immunodeficiency caused by mutations in Wiskott-Aldrich syndrome protein (WASp), a key regulator of cytoskeletal dynamics in hematopoietic cells. A high proportion of patients experience autoimmunity caused by a breakdown in T- and B-cell tolerance. Moreover, excessive production of type I interferon (IFN-I) by plasmacytoid dendritic cells (pDCs) contributes to autoimmune signs; however, the factors that trigger excessive innate activation have not been defined. Objective Neutrophil extracellular traps (NETs) emerged as major initiating factors in patients with diseases such as systemic lupus erythematosus and rheumatoid arthritis. In this study we explored the possible involvement of aberrant neutrophil functions in patients with WAS. Methods We evaluated the expression of a set of granulocyte genes associated with NETs in a cohort of patients with WAS and the presence of NET inducers in sera. Using a mouse model of WAS, we analyzed NET release by WASp-null neutrophils and evaluated the composition and homeostasis of neutrophils in vivo . By using depletion experiments, we assessed the effect of neutrophils in promoting inflammation and reactivity against autoantigens. Results Transcripts of genes encoding neutrophil enzymes and antimicrobial peptides were increased in granulocytes of patients with WAS, and serum-soluble factors triggered NET release. WASp-null neutrophils showed increased spontaneous NETosis, induced IFN-I production by pDCs, and activated B cells through B-cell activating factor. Consistently, their depletion abolished constitutive pDC activation, normalized circulating IFN-I levels, and, importantly, abolished production of autoantibodies directed against double-stranded DNA, nucleosomes, and myeloperoxidase. Conclusions These findings reveal that neutrophils are involved in the pathogenic loop that causes excessive activation of innate cells and autoreactive B cells, thus identifying novel mechanisms that contribute to the autoimmunity of WAS.