The human CIB1-EVER1-EVER2 complex governs keratinocyte-intrinsic immunity to β-papillomaviruses

Inherited human RelB deficiency impairs innate and adaptive immunity to infection

We report two unrelated adults with homozygous (P1) or compound heterozygous (P2) private loss-of-function variants of V-Rel Reticuloendotheliosis Viral Oncogene Homolog B (RELB). The resulting deficiency of functional RelB impairs the induction of NFKB2 mRNA and NF-κB2 (p100/p52) protein by lymphotoxin in the fibroblasts of the patients. These defects are rescued by transduction with wild-type RELB complementary DNA (cDNA). By contrast, the response of RelB-deficient fibroblasts to Tumor Necrosis Factor (TNF) or IL-1β via the canonical NF-κB pathway remains intact. P1 and P2 have low proportions of naïve CD4+ and CD8+ T cells and of memory B cells. Moreover, their naïve B cells cannot differentiate into immunoglobulin G (IgG)- or immunoglobulin A (IgA)-secreting cells in response to CD40L/IL-21, and the development of IL-17A/F-producing T cells is strongly impaired in vitro. Finally, the patients produce neutralizing autoantibodies against type I interferons (IFNs), even after hematopoietic stem cell transplantation, attesting to a persistent dysfunction of thymic epithelial cells in T cell selection and central tolerance to some autoantigens. Thus, inherited human RelB deficiency disrupts the alternative NF-κB pathway, underlying a T- and B cell immunodeficiency, which, together with neutralizing autoantibodies against type I IFNs, confers a predisposition to viral, bacterial, and fungal infections.

Case Report of Two Independent Moroccan Families with Syndromic Epidermodysplasia Verruciformis and STK4 Deficiency

Epidermodysplasia verruciformis (EV) is a rare genodermatosis caused by β-human papillomaviruses (HPV) in immunodeficient patients. EV is characterized by flat warts and pityriasis-like lesions and might be isolated or syndromic, associated with some other infectious manifestations. We report here three patients from two independent families, with syndromic EV for both of them. By whole exome sequencing, we found that the patients carry new homozygous variants in STK4, both leading to a premature stop codon. STK4 deficiency causes a combined immunodeficiency characterized by a broad infectious susceptibility to bacteria, viruses, and fungi. Auto-immune manifestations were also reported. Deep immunophenotyping revealed multiple cytopenia in the three affected patients, in particular deep CD4+ T cells deficiency. We report here the fourth and the fifth cases of the syndromic EV due to STK4 deficiency.

Insights into the genetic theory of infectious diseases

Over the past century, classical approaches from microbiology and immunology have produced spectacular results in the control of infectious diseases. However, the recent SARS-COV-2 pandemic has highlighted our continued failure to control some infections. Other microorganisms still pose a threat to humanity such as HIV, Ebola, and influenza viruses. It seems that conventional approaches are not able to solve all the current problems caused by infectious diseases. Human genetics has shown that infections have a strong genetic determinism that can lead to a predisposition or resistance to infections. This explains much of the clinical variability observed in individuals infected with the same pathogen. The identification of the genetic etiology allows a better understanding of the pathogenesis of infectious diseases and, consequently, the consideration of appropriate preventive and therapeutic strategies. This review provides insights into the genetic theory and the concrete evidence to support it. We highlight the role of primary immunodeficiencies in the discovery of Mendelian and monogenic susceptibility to infections, then we show how genetic and phenotypic heterogeneity, redundancy, and resistance to infection manifest in the context of this genetic determinism. To effectively combat the constant threat of microbes, it is essential to integrate human genetics with microbiology to examine the interactions between pathogens and our immune system.

Sequence variations and accessory proteins adapt TMC functions to distinct sensory modalities

Transmembrane channel-like (TMC) proteins are expressed throughout the animal kingdom and are thought to encode components of ion channels. Mammals express eight TMCs (mTMC1-8), two of which (mTMC1 and mTMC2) are subunits of mechanotransduction channels. C. elegans expresses two TMCs (TMC-1 and TMC-2), which mediate mechanosensation, egg laying, and alkaline sensing. The mechanisms by which nematode TMCs contribute to such diverse physiological processes and their functional relationship to mammalian mTMCs is unclear. Here, we show that association with accessory proteins tunes nematode TMC-1 to divergent sensory functions. In addition, distinct TMC-1 domains enable touch and alkaline sensing. Strikingly, these domains are segregated in mammals between mTMC1 and mTMC3. Consistent with these findings, mammalian mTMC1 can mediate mechanosensation in nematodes, while mTMC3 can mediate alkaline sensation. We conclude that sequence diversification and association with accessory proteins has led to the emergence of TMC protein complexes with diverse properties and physiological functions.

Epidermodysplasia Verruciformis and Vδ2 γδ T-cell Expansion in STK4 Deficiency

The clinical penetrance of infectious diseases varies considerably among patients with inborn errors of immunity (IEI), even for identical genetic defects. This variability is influenced by pathogen exposure, healthcare access and host-environment interactions. We describe here a patient in his thirties who presented with epidermodysplasia verruciformis (EV) due to infection with a weakly virulent beta-papillomavirus (HPV38) and CD4+ T-cell lymphopenia. The patient was born to consanguineous parents living in the United States. Exome sequencing identified a previously unknown biallelic STK4 stop-gain mutation (p.Trp425X). The patient had no relevant history of infectious disease during childhood other than mild wart-like lesion on the skin, but he developed diffuse large B-cell lymphoma (DLBCL) and EBV viremia with a low viral load in his thirties. Despite his low CD4+ T-cell count, the patient had normal counts of CD3+ cells, predominantly double-negative T cells (67.4%), which turned out to be Vδ2+ γδ T cells. γδ T-cell expansion has frequently been observed in the 33 reported cases with STK4 deficiency. The Vδ2 γδ T cells of this STK4-deficient patient are mostly CD45RA-CD27+CCR7+ central memory γδT cells, and their ability to proliferate in response to T-cell activation was impaired, as was that of CD4+ T cells. In conclusion, γδ T-cell expansion may act as a compensatory mechanism to combat viral infection, providing immune protection in immunocompromised individuals.

Human TMEFF1 is a restriction factor for herpes simplex virus in the brain

Most cases of herpes simplex virus 1 (HSV-1) encephalitis (HSE) remain unexplained1,2. Here, we report on two unrelated people who had HSE as children and are homozygous for rare deleterious variants of TMEFF1, which encodes a cell membrane protein that is preferentially expressed by brain cortical neurons. TMEFF1 interacts with the cell-surface HSV-1 receptor NECTIN-1, impairing HSV-1 glycoprotein D- and NECTIN-1-mediated fusion of the virus and the cell membrane, blocking viral entry. Genetic TMEFF1 deficiency allows HSV-1 to rapidly enter cortical neurons that are either patient specific or derived from CRISPR-Cas9-engineered human pluripotent stem cells, thereby enhancing HSV-1 translocation to the nucleus and subsequent replication. This cellular phenotype can be rescued by pretreatment with type I interferon (IFN) or the expression of exogenous wild-type TMEFF1. Moreover, ectopic expression of full-length TMEFF1 or its amino-terminal extracellular domain, but not its carboxy-terminal intracellular domain, impairs HSV-1 entry into NECTIN-1-expressing cells other than neurons, increasing their resistance to HSV-1 infection. Human TMEFF1 is therefore a host restriction factor for HSV-1 entry into cortical neurons. Its constitutively high abundance in cortical neurons protects these cells from HSV-1 infection, whereas inherited TMEFF1 deficiency renders them susceptible to this virus and can therefore underlie HSE.

Deficiency in Ever2 does not increase susceptibility of mice to pathogenesis by the mouse papillomavirus, MmuPV1

Epidermodysplasia verruciformis (EV) is a rare genetic skin disorder that is characterized by the development of papillomavirus-induced skin lesions that can progress to squamous cell carcinoma (SCC). Certain high-risk, cutaneous β-genus human papillomaviruses (β-HPVs), in particular HPV5 and HPV8, are associated with inducing EV in individuals who have a homozygous mutation in one of three genes tied to this disease: EVER1, EVER2, or CIB1. EVER1 and EVER2 are also known as TMC6 and TMC8, respectively. Little is known about the biochemical activities of EVER gene products or their roles in facilitating EV in conjunction with β-HPV infection. To investigate the potential effect of EVER genes on papillomavirus infection, we pursued in vivo infection studies by infecting Ever2-null mice with mouse papillomavirus (MmuPV1). MmuPV1 shares characteristics with β-HPVs including similar genome organization, shared molecular activities of their early, E6 and E7, oncoproteins, the lack of a viral E5 gene, and the capacity to cause skin lesions that can progress to SCC. MmuPV1 infections were conducted both in the presence and absence of UVB irradiation, which is known to increase the risk of MmuPV1-induced pathogenesis. Infection with MmuPV1 induced skin lesions in both wild-type and Ever2-null mice with and without UVB. Many lesions in both genotypes progressed to malignancy, and the disease severity did not differ between Ever2-null and wild-type mice. However, somewhat surprisingly, lesion growth and viral transcription was decreased, and lesion regression was increased in Ever2-null mice compared with wild-type mice. These studies demonstrate that Ever2-null mice infected with MmuPV1 do not exhibit the same phenotype as human EV patients infected with β-HPVs.IMPORTANCEHumans with homozygous mutations in the EVER2 gene develop epidermodysplasia verruciformis (EV), a disease characterized by predisposition to persistent β-genus human papillomavirus (β-HPV) skin infections, which can progress to skin cancer. To investigate how EVER2 confers protection from papillomaviruses, we infected the skin of homozygous Ever2-null mice with mouse papillomavirus MmuPV1. Like in humans with EV, infected Ever2-null mice developed skin lesions that could progress to cancer. Unlike in humans with EV, lesions in these Ever2-null mice grew more slowly and regressed more frequently than in wild-type mice. MmuPV1 transcription was higher in wild-type mice than in Ever2-null mice, indicating that mouse EVER2 does not confer protection from papillomaviruses. These findings suggest that there are functional differences between MmuPV1 and β-HPVs and/or between mouse and human EVER2.

Therapeutic Role of HPV Vaccination on Benign HPV-induced Epithelial Proliferations in Immunocompetent and Immunocompromised Patients: Case Study and Review of the Literature

Human papillomavirus (HPV) vaccination represents a milestone in primary prevention of sexually transmitted infections. However, little is known about its possible effects on already established HPV infections. We report the case of a 9-year-old immunosuppressed girl with refractory warts, successfully treated with the nonavalent-HPV vaccine and review the literature about the therapeutic effects of HPV vaccination on benign HPV-induced epithelial proliferations in immunocompetent and immunosuppressed patients. In the literature, promising results were shown on cutaneous warts after HPV vaccination, especially in children and young adults, also in immunosuppressed patients, whereas controverse results were found on anogenital warts. These findings suggest a critical need for randomized clinical trials to assess the efficacy of HPV vaccination in the treatment of benign HPV-induced epithelial proliferations.

A deep learning method for classification of HNSCC and HPV patients using single-cell transcriptomics

Background

Head and Neck Squamous Cell Carcinoma (HNSCC) is the seventh most highly prevalent cancer type worldwide. Early detection of HNSCC is one of the important challenges in managing the treatment of the cancer patients. Existing techniques for detecting HNSCC are costly, expensive, and invasive in nature.

Methods

In this study, we aimed to address this issue by developing classification models using machine learning and deep learning techniques, focusing on single-cell transcriptomics to distinguish between HNSCC and normal samples. Furthermore, we built models to classify HNSCC samples into HPV-positive (HPV+) and HPV-negative (HPV-) categories. In this study, we have used GSE181919 dataset, we have extracted 20 primary cancer (HNSCC) samples, and 9 normal tissues samples. The primary cancer samples contained 13 HPV- and 7 HPV+ samples. The models developed in this study have been trained on 80% of the dataset and validated on the remaining 20%. To develop an efficient model, we performed feature selection using mRMR method to shortlist a small number of genes from a plethora of genes. We also performed Gene Ontology (GO) enrichment analysis on the 100 shortlisted genes.

Results

Artificial Neural Network based model trained on 100 genes outperformed the other classifiers with an AUROC of 0.91 for HNSCC classification for the validation set. The same algorithm achieved an AUROC of 0.83 for the classification of HPV+ and HPV- patients on the validation set. In GO enrichment analysis, it was found that most genes were involved in binding and catalytic activities.

Conclusion

A software package has been developed in Python which allows users to identify HNSCC in patients along with their HPV status. It is available at https://webs.iiitd.edu.in/raghava/hnscpred/.

Human Papillomavirus Carcinogenicity and the Need of New Perspectives: Thoughts from a Retrospective Analysis on Human Papillomavirus Outcomes Conducted at the Hospital University of Bari, Apulia, Italy, between 2011 and 2022

BACKGROUND

The current manuscript's aim was to determine the human papillomavirus (HPV) genotype-specific prevalence and distribution among individuals, males, and females, of different ages in the region of Apulia, Italy, highlighting the possible variables involved in the carcinogenicity mechanism. In addition, we proposed two hypothetical models of HPV's molecular dynamics, intending to clarify the impact of prevention and therapeutic strategies, explicitly modeled by recent survey data.

METHODS

We presented clinical data from 9647 participants tested for either high-risk (HR) or low-risk (LR) HPV at the affiliated Bari Policlinic University Hospital of Bari from 2011 to 2022. HPV DNA detection was performed using nested-polymerase chain reaction (PCR) and multiplex real-time PCR assay. Statistical analysis showed significant associations for all genders and ages and both HR- and LR-HPV types. A major number of significant pairwise associations were detected for the higher-risk types and females and lower-risk types and males.

RESULTS

The overall prevalence of HPV was 50.5% (n-4.869) vs. 49.5% (n-4.778) of the study population, of which 74.4% (n-3621) were found to be HPV high-risk (HR-HPV) genotypes and 57.7% (n-2.807) low-risk HPV (LR-HPV) genotypes, of which males were 58% and females 49%; the three most prevalent HR-HPV genotypes were HPV 53 (n707-15%), 16 (n704-14%), and 31 (n589-12%), and for LR-HPV, they were 42 (19%), 6 (16%), and 54 (13%); 56% of patients screened for HPV were ≤ 30 years old, 53% were between 31 and 40 years old, 46% were 41-50 and 51-60 years old, and finally, 44% of subjects were >60 years old.

CONCLUSIONS

Our study provided comprehensive epidemiological data on HPV prevalence and genotype distribution among 9647 participants, which could serve as a significant reference for clinical practice, and it implied the necessity for more effective screening methods for HPV carcinogenesis covering the use of more specific molecular investigations. Although this is a predominantly descriptive and epidemiological study, the data obtained offer not only a fairly unique trend compared to other studies of different realities and latitudes but also lead us to focus on the HPV infection within two groups of young people and adults and hypothesize the possible involvement of dysbiosis, stem cells, and the retrotransposition mechanism.

TMC7 functions as a suppressor of Piezo2 in primary sensory neurons blunting peripheral mechanotransduction

The transmembrane channel-like (TMC) protein family comprises eight members, with TMC1 and TMC2 being extensively studied. This study demonstrates substantial co-expression of TMC7 with the mechanosensitive channel Piezo2 in somatosensory neurons. Genetic deletion of TMC7 in primary sensory ganglia neurons in vivo enhances sensitivity in both physiological and pathological mechanosensory transduction. This deletion leads to an increase in proportion of rapidly adapting (RA) currents conducted by Piezo2 in dorsal root ganglion (DRG) neurons and accelerates RA deactivation kinetics. In HEK293 cells expressing both proteins, TMC7 significantly suppresses the current amplitudes of co-expressed Piezo2. Our findings reveal that TMC7 and Piezo2 exhibit physical interactions, and both proteins also physically interact with cytoskeletal β-actin. We hypothesize that TMC7 functions as an inhibitory modulator of Piezo2 in DRG neurons, either through direct inhibition or by disrupting the transmission of mechanical forces from the cytoskeleton to the channel.

Life-threatening infections in human newborns: Reconciling age-specific vulnerability and interindividual variability

In humans, the interindividual variability of clinical outcome following exposure to a microorganism is immense, ranging from silent infection to life-threatening disease. Age-specific immune responses partially account for the high incidence of infection during the first 28 days of life and the related high mortality at population level. However, the occurrence of life-threatening disease in individual newborns remains unexplained. By contrast, inborn errors of immunity and their immune phenocopies are increasingly being discovered in children and adults with life-threatening viral, bacterial, mycobacterial and fungal infections. There is a need for convergence between the fields of neonatal immunology, with its in-depth population-wide characterization of newborn-specific immune responses, and clinical immunology, with its investigations of infections in patients at the cellular and molecular levels, to facilitate identification of the mechanisms of susceptibility to infection in individual newborns and the design of novel preventive and therapeutic strategies.

Rubella virus chronic inflammatory disease and other unusual viral phenotypes in inborn errors of immunity

Infectious susceptibility is a component of many inborn errors of immunity. Nevertheless, antibiotic use is often used as a surrogate in history taking for infectious susceptibility, thereby disadvantaging patients who present with viral infections as their phenotype. Further complicating clinical evaluations are unusual manifestations of viral infections which may be less familiar that the typical respiratory viral infections. This review covers several unusual viral phenotypes arising in patients with inborn errors of immunity and other settings of immune compromise. In some cases, chronic infections lead to oncogenesis or tumor-like growths and the conditions and mechanisms of viral-induced oncogenesis will be described. This review covers enterovirus, rubella, measles, papillomavirus, and parvovirus B19. It does not cover EBV and hemophagocytic lymphohistiocytosis nor lymphomagenesis related to EBV. EBV susceptibility has been recently reviewed. Our goal is to increase awareness of the unusual manifestations of viral infections in patients with IEI and to describe treatment modalities utilized in this setting. Coincidentally, each of the discussed viral infections can have a cutaneous component and figures will serve as a reminder of the physical features of these viruses. Given the high morbidity and mortality, early recognition can only improve outcomes.

Inborn errors of immunity: an expanding universe of disease and genetic architecture

Inborn errors of immunity (IEIs) are generally considered to be rare monogenic disorders of the immune system that cause immunodeficiency, autoinflammation, autoimmunity, allergy and/or cancer. Here, we discuss evidence that IEIs need not be rare disorders or exclusively affect the immune system. Namely, an increasing number of patients with IEIs present with severe dysregulations of the central nervous, digestive, renal or pulmonary systems. Current challenges in the diagnosis of IEIs that result from the segregated practice of specialized medicine could thus be mitigated, in part, by immunogenetic approaches. Starting with a brief historical overview of IEIs, we then discuss the technological advances that are facilitating the immunogenetic study of IEIs, progress in understanding disease penetrance in IEIs, the expanding universe of IEIs affecting distal organ systems and the future of genetic, biochemical and medical discoveries in this field.

The transmembrane channel-like 6 (TMC6) in primary sensory neurons involving thermal sensation via modulating M channels

Introduction: The transmembrane channel-like (TMC) protein family contains eight members, TMC1-TMC8. Among these members, only TMC1 and TMC2 have been intensively studied. They are expressed in cochlear hair cells and are crucial for auditory sensations. TMC6 and TMC8 contribute to epidermodysplasia verruciformis, and predispose individuals to human papilloma virus. However, the impact of TMC on peripheral sensation pain has not been previously investigated. Methods: RNAscope was employed to detect the distribution of TMC6 mRNA in DRG neurons. Electrophysiological recordings were conducted to investigate the effects of TMC6 on neuronal characteristics and M channel activity. Zn2+ indicators were utilized to detect the zinc concentration in DRG tissues and dissociated neurons. A series of behavioural tests were performed to assess thermal and mechanical sensation in mice under both physiological and pathological conditions. Results and Discussion: We demonstrated that TMC6 is mainly expressed in small and medium dorsal root ganglion (DRG) neurons and is involved in peripheral heat nociception. Deletion of TMC6 in DRG neurons hyperpolarizes the resting membrane potential and inhibits neuronal excitability. Additionally, the function of the M channel is enhanced in TMC6 deletion DRG neurons owing to the increased quantity of free zinc in neurons. Indeed, heat and mechanical hyperalgesia in chronic pain are alleviated in TMC6 knockout mice, particularly in the case of heat hyperalgesia. This suggests that TMC6 in the small and medium DRG neurons may be a potential target for chronic pain treatment.

Monogenic etiologies of persistent human papillomavirus infections: A comprehensive systematic review

PURPOSE

Persistent human papillomavirus infection (PHPVI) causes cutaneous, anogenital, and mucosal warts. Cutaneous warts include common warts, Treeman syndrome, and epidermodysplasia verruciformis, among others. Although more reports of monogenic predisposition to PHPVI have been published with the development of genomic technologies, genetic testing is rarely incorporated into clinical assessments. To encourage broader molecular testing, we compiled a list of the various monogenic etiologies of PHPVI.

METHODS

We conducted a systematic literature review to determine the genetic, immunological, and clinical characteristics of patients with PHPVI.

RESULTS

The inclusion criteria were met by 261 of 40,687 articles. In 842 patients, 83 PHPVI-associated genes were identified, including 42, 6, and 35 genes with strong, moderate, and weak evidence for causality, respectively. Autosomal recessive inheritance predominated (69%). PHPVI onset age was 10.8 ± 8.6 years, with an interquartile range of 5 to 14 years. GATA2,IL2RG,DOCK8, CXCR4, TMC6, TMC8, and CIB1 are the most frequently reported PHPVI-associated genes with strong causality. Most genes (74 out of 83) belong to a catalog of 485 inborn errors of immunity-related genes, and 40 genes (54%) are represented in the nonsyndromic and syndromic combined immunodeficiency categories.

CONCLUSION

PHPVI has at least 83 monogenic etiologies and a genetic diagnosis is essential for effective management.

Human genetic errors of immunity illuminate an adaptive arsenal model of rapid defenses

New discoveries in the field of human monogenic immune diseases highlight critical genes and pathways governing immune responses. Here, I describe how the ~500 currently defined human inborn errors of immunity help shape what I propose is an 'adaptive arsenal model of rapid defenses', emphasizing the set of immunological defenses poised for rapid responses in the natural environment. This arsenal blurs the lines between innate and adaptive immunity and is established through molecular relays between cell types, often traversing from sensors (pathogen detection) to intermediates to executioners (pathogen clearance) via soluble factors. Predictions and missing information based on the adaptive arsenal model are discussed, as are emergent and outstanding questions fundamental to advances in the field.

Interactions among human papillomavirus proteins and host DNA repair factors differ during the viral life cycle and virus-induced tumorigenesis

This review focuses on the impact of human papillomavirus (HPV) oncogenes on DNA repair pathways with a particular focus on how these relationships change as productive HPV infections transition to malignant lesions. We made specific efforts to incorporate advances in the understanding of HPV and DNA damage repair over the last 4 years. We apologize for any articles that we missed in compiling this report.

Comparative Analysis of Alpha and Beta HPV E6 Oncoproteins: Insights into Functional Distinctions and Divergent Mechanisms of Pathogenesis

Human papillomaviruses (HPVs) represent a diverse group of DNA viruses that infect epithelial cells of mucosal and cutaneous tissues, leading to a wide spectrum of clinical outcomes. Among various HPVs, alpha (α) and beta (β) types have garnered significant attention due to their associations with human health. α-HPVs are primarily linked to infections of the mucosa, with high-risk subtypes, such as HPV16 and HPV18, being the major etiological agents of cervical and oropharyngeal cancers. In contrast, β-HPVs are predominantly associated with cutaneous infections and are commonly found on healthy skin. However, certain β-types, notably HPV5 and HPV8, have been implicated in the development of non-melanoma skin cancers in immunocompromised individuals, highlighting their potential role in pathogenicity. In this review, we comprehensively analyze the similarities and differences between α- and β-HPV E6 oncoproteins, one of the major drivers of viral replication and cellular transformation, and how these impact viral fitness and the capacity to induce malignancy. In particular, we compare the mechanisms these oncoproteins use to modulate common cellular processes-apoptosis, DNA damage repair, cell differentiation, and the immune response-further shedding light on their shared and distinct features, which enable them to replicate at divergent locations of the human body and cause different types of cancer.

Single-cell RNA-seq public data reveal the gene regulatory network landscape of respiratory epithelial and peripheral immune cells in COVID-19 patients

Introduction

Infection with SARS-CoV-2 leads to coronavirus disease 2019 (COVID-19), which can result in acute respiratory distress syndrome and multiple organ failure. However, its comprehensive influence on pathological immune responses in the respiratory epithelium and peripheral immune cells is not yet fully understood.

Methods

In this study, we analyzed multiple public scRNA-seq datasets of nasopharyngeal swabs and peripheral blood to investigate the gene regulatory networks (GRNs) of healthy individuals and COVID-19 patients with mild/moderate and severe disease, respectively. Cell-cell communication networks among cell types were also inferred. Finally, validations were conducted using bulk RNA-seq and proteome data.

Results

Similar and dissimilar regulons were identified within or between epithelial and immune cells during COVID-19 severity progression. The relative transcription factors (TFs) and their targets were used to construct GRNs among different infection sites and conditions. Between respiratory epithelial and peripheral immune cells, different TFs tended to be used to regulate the activity of a cell between healthy individuals and COVID-19 patients, although they had some TFs in common. For example, XBP1, FOS, STAT1, and STAT2 were activated in both the epithelial and immune cells of virus-infected individuals. In contrast, severe COVID-19 cases exhibited activation of CEBPD in peripheral immune cells, while CEBPB was exclusively activated in respiratory epithelial cells. Moreover, in patients with severe COVID-19, although some inflammatory genes, such as S100A8/A9, were found to be upregulated in both respiratory epithelial and peripheral immune cells, their relative regulators can differ in terms of cell types. The cell-cell communication analysis suggested that epidermal growth factor receptor signaling among epithelia contributes to mild/moderate disease, and chemokine signaling among immune cells contributes to severe disease.

Conclusion

This study identified cell type- and condition-specific regulons in a wide range of cell types from the initial infection site to the peripheral blood, and clarified the diverse mechanisms of maladaptive responses to SARS-CoV-2 infection.

Cutaneous Findings in Inborn Errors of Immunity: An Immunologist's Perspective

Cutaneous manifestations are common in patients with inborn errors of immunity (IEI)/primary immunodeficiency and could be due to infections, immune dysregulation, or lymphoproliferative/malign diseases. Immunologists accept some as warning signs for underlying IEI. Herein, we include noninfectious/infectious cutaneous manifestations that we come across in rare IEI cases in our clinic and provide a comprehensive literature review. For several skin diseases, the diagnosis is challenging and differential diagnosis is necessary. Detailed disease history and examination play a vital role in reaching a diagnosis, especially if there is a potential underlying IEI. A skin biopsy is sometimes necessary, especially if we need to rule out inflammatory, infectious, lymphoproliferative, and malignant conditions. Specific and immunohistochemical stainings are particularly important when diagnosing granuloma, amyloidosis, malignancies, and infections like human herpes virus-6, human herpes virus-8, human papillomavirus, and orf. Elucidation of mechanisms of IEIs has improved our understanding of their relation to cutaneous findings. In challenging cases, the immunological evaluation may lead the approach when there is a specific primary immunodeficiency diagnosis or at least help to reduce the number of differential diagnoses. Conversely, the response to therapy may provide conclusive evidence for some conditions. This review raises awareness of concomitant lesions and expands the scope of the differential diagnosis of IEI and the spectrum of skin disease therapy by highlighting frequent forms of IEI-associated cutaneous manifestations. The manifestations given here will guide clinicians to plan for alternative use of diverse therapeutics in a multidisciplinary way for skin diseases.

Advances in cutaneous squamous cell carcinoma

Human malignancies arise predominantly in tissues of epithelial origin, where the stepwise transformation from healthy epithelium to premalignant dysplasia to invasive neoplasia involves sequential dysregulation of biological networks that govern essential functions of epithelial homeostasis. Cutaneous squamous cell carcinoma (cSCC) is a prototype epithelial malignancy, often with a high tumour mutational burden. A plethora of risk genes, dominated by UV-induced sun damage, drive disease progression in conjunction with stromal interactions and local immunomodulation, enabling continuous tumour growth. Recent studies have identified subpopulations of SCC cells that specifically interact with the tumour microenvironment. These advances, along with increased knowledge of the impact of germline genetics and somatic mutations on cSCC development, have led to a greater appreciation of the complexity of skin cancer pathogenesis and have enabled progress in neoadjuvant immunotherapy, which has improved pathological complete response rates. Although measures for the prevention and therapeutic management of cSCC are associated with clinical benefit, the prognosis remains poor for advanced disease. Elucidating how the genetic mechanisms that drive cSCC interact with the tumour microenvironment is a current focus in efforts to understand, prevent and treat cSCC.

Atypical Cutaneous Viral Infections Reveal an Inborn Error of Immunity in 8 Patients

Unusual viral skin infections might be the first clinical manifestation in children with an inborn error of immunity (IEI). We performed a prospective study from 1 October 2017 to 30 September 2021, at the Department of Pediatric Infectious Diseases and Clinical Immunity of Ibn Rochd University Hospital-Casablanca. During this period, on 591 patients newly diagnosed with a probable IEI, eight of them (1.3%), from six independent families, had isolated or syndromic unusual viral skin infections, which were either profuse, chronic or recurrent infections, and resistant to any treatment. The median age of disease onset was nine years old and all patients were born from a first-degree consanguineous marriage. By combining clinical, immunological and genetic investigations, we identified GATA2 deficiency in one patient with recalcitrant profuse verrucous lesions and monocytopenia (1/8) and STK4 deficiency in two families with HPV lesions, either flat or common warts, and lymphopenia (2/8), as previously reported. We also identified COPA deficiency in twin sisters with chronic profuse Molluscum contagiosum lesions, pulmonary diseases and microcytic hypochromic anemia (2/8). Finally, we also found one patient with chronic profuse MC lesions and hyper IgE syndrome, (1/8) and two patients with either recalcitrant profuse verrucous lesions or recurrent post-herpetic erythema multiforme and a combined immunodeficiency (2/8) with no genetic defect identified yet. Raising clinicians awareness that infectious skin diseases might be the consequence of an inborn error of immunity would allow for optimized diagnosis, prevention and treatment of patients and their families.

Reconciling Mouse and Human Immunology at the Altar of Genetics

Immunity to infection has been extensively studied in humans and mice bearing naturally occurring or experimentally introduced germline mutations. Mouse studies are sometimes neglected by human immunologists, on the basis that mice are not humans and the infections studied are experimental and not natural. Conversely, human studies are sometimes neglected by mouse immunologists, on the basis of the uncontrolled conditions of study and small numbers of patients. However, both sides would agree that the infectious phenotypes of patients with inborn errors of immunity often differ from those of the corresponding mutant mice. Why is that? We argue that this important question is best addressed by revisiting and reinterpreting the findings of both mouse and human studies from a genetic perspective. Greater caution is required for reverse-genetics studies than for forward-genetics studies, but genetic analysis is sufficiently strong to define the studies likely to stand the test of time. Genetically robust mouse and human studies can provide invaluable complementary insights into the mechanisms of immunity to infection common and specific to these two species.

Whole transcriptome-based skin virome profiling in typical epidermodysplasia verruciformis reveals α-, β-, and γ-HPV infections

HPVs are DNA viruses include approximately 450 types that are classified into 5 genera (α-, β-, γ-, μ-, and ν-HPV). The γ- and β-HPVs are present in low copy numbers in healthy individuals; however, in patients with an inborn error of immunity, certain species of β-HPVs can cause epidermodysplasia verruciformis (EV), manifesting as recalcitrant cutaneous warts and skin cancer. EV presents as either typical or atypical. Manifestations of typical EV are limited to the skin and are caused by abnormal keratinocyte-intrinsic immunity to β-HPVs due to pathogenic sequence variants in TMC6, TMC8, or CIB1. We applied a transcriptome-based computational pipeline, VirPy, to RNA extracted from normal-appearing skin and wart samples of patients with typical EV to explore the viral and human genetic determinants. In 26 patients, 9 distinct biallelic mutations were detected in TMC6, TMC8, and CIB1, 7 of which are previously unreported to our knowledge. Additionally, 20 different HPV species, including 3 α-HPVs, 16 β-HPVs, and 1 γ-HPV, were detected, 8 of which are reported here for the first time to our knowledge in patients with EV (β-HPV-37, -47, -80, -151, and -159; α-HPV-2 and -57; and γ-HPV-128). This study expands the TMC6, TMC8, and CIB1 sequence variant spectrum and implicates new HPV subtypes in the pathogenesis of typical EV.

Recent advances in cutaneous HPV infection

More than 200 types of human papillomavirus (HPV) have been reported to date and have been associated with various dermatological diseases. Among dermatological diseases, viral verrucae are the most commonly reported to be associated with HPV. Epidermodysplasia verruciformis (EV) consists of three types: typical EV is an autosomal recessive genetic disorder with TMC6/TMC8 gene mutations, atypical EV develops due to various gene mutations that cause immunodeficiency, and acquired EV develops due to acquired immunodeficiency. Generalized verrucosis differs from EV in that it involves numerous verrucous nodules (mainly on the limbs), histopathologically no blue cells as seen in EV, and infection with cutaneous α-HPVs as well as β-HPVs. HPV-induced skin malignancies include squamous cell carcinoma (SCC) caused by β-HPV (especially HPV types 5 and 8) in EV patients, organ transplant recipients, and healthy individuals, and SCC of the vulva and nail unit caused by mucosal high-risk HPV infection. Carcinogenesis of β-HPV is associated with sunlight. Mucosal high-risk HPV-associated carcinomas may also be sexually transmitted. We focused on Bowen's disease of the nail, which has been the subject of our research for a long time and has recently come to the fore in the field of dermatology.

How to recognize inborn errors of immunity in a child presenting with a malignancy: guidelines for the pediatric hemato-oncologist

Inborn errors of immunity (IEI) are a group of disorders caused by genetically determined defects in the immune system, leading to infections, autoimmunity, autoinflammation and an increased risk of malignancy. In some cases, a malignancy might be the first sign of an underlying IEI. As therapeutic strategies might be different in these patients, recognition of the underlying IEI by the pediatric hemato-oncologist is important. This article, written by a group of experts in pediatric immunology, hemato-oncology, pathology and genetics, aims to provide guidelines for pediatric hemato-oncologists on how to recognize a possible underlying IEI and what diagnostic tests can be performed, and gives some consideration to treatment possibilities.

Fulminant Viral Hepatitis in Two Siblings with Inherited IL-10RB Deficiency

Fulminant viral hepatitis (FVH) caused by hepatitis A virus (HAV) is a life-threatening disease that typically strikes otherwise healthy individuals. The only known genetic etiology of FVH is inherited IL-18BP deficiency, which unleashes IL-18-dependent lymphocyte cytotoxicity and IFN-γ production. We studied two siblings who died from a combination of early-onset inflammatory bowel disease (EOIBD) and FVH due to HAV. The sibling tested was homozygous for the W100G variant of IL10RB previously described in an unrelated patient with EOIBD. We show here that the out-of-frame IL10RB variants seen in other EOIBD patients disrupt cellular responses to IL-10, IL-22, IL-26, and IFN-λs in overexpression conditions and in homozygous cells. By contrast, the impact of in-frame disease-causing variants varies between cases. When overexpressed, the W100G variant impairs cellular responses to IL-10, but not to IL-22, IL-26, or IFN-λ1, whereas cells homozygous for W100G do not respond to IL-10, IL-22, IL-26, or IFN-λ1. As IL-10 is a potent antagonist of IFN-γ in phagocytes, these findings suggest that the molecular basis of FVH in patients with IL-18BP or IL-10RB deficiency may involve excessive IFN-γ activity during HAV infections of the liver. Inherited IL-10RB deficiency, and possibly inherited IL-10 and IL-10RA deficiencies, confer a predisposition to FVH, and patients with these deficiencies should be vaccinated against HAV and other liver-tropic viruses.

Transcription Properties of Beta-HPV8 and HPV38 Genomes in Human Keratinocytes

Persistent infections with high-risk human papillomaviruses (HR-HPV) from the genus alpha are established risk factors for the development of anogenital and oropharyngeal cancers. In contrast, HPV from the genus beta have been implicated in the development of cutaneous squamous cell cancer (cSCC) in epidermodysplasia verruciformis (EV) patients and organ transplant recipients. Keratinocytes are the in vivo target cells for HPV, but keratinocyte models to investigate the replication and oncogenic activities of beta-HPV genomes have not been established. A recent study revealed, that beta-HPV49 immortalizes normal human keratinocytes (NHK) only, when the viral E8^E2 repressor (E8^-) is inactivated (T. M. Rehm, E. Straub, T. Iftner, and F. Stubenrauch, Proc Natl Acad Sci U S A 119:e2118930119, 2022, https://doi.org/10.1073/pnas.2118930119). We now demonstrate that beta-HPV8 and HPV38 wild-type or E8^- genomes are unable to immortalize NHK. Nevertheless, HPV8 and HPV38 express E6 and E7 oncogenes and other transcripts in transfected NHK. Inactivation of the conserved E1 and E2 replication genes reduces viral transcription, whereas E8^- genomes display enhanced viral transcription, suggesting that beta-HPV genomes replicate in NHK. Furthermore, growth of HPV8- or HPV38-transfected NHK in organotypic cultures, which are routinely used to analyze the productive replication cycle of HR-HPV, induces transcripts encoding the L1 capsid gene, suggesting that the productive cycle is initiated. In addition, transcription patterns in HPV8 organotypic cultures and in an HPV8-positive lesion from an EV patient show similarities. Taken together, these data indicate that NHK are a suitable system to analyze beta-HPV8 and HPV38 replication. IMPORTANCE High-risk HPV, from the genus alpha, can cause anogenital or oropharyngeal malignancies. The oncogenic properties of high-risk HPV are important for their differentiation-dependent replication in human keratinocytes, the natural target cell for HPV. HPV from the genus beta have been implicated in the development of cutaneous squamous cell cancer in epidermodysplasia verruciformis (EV) patients and organ transplant recipients. Currently, the replication cycle of beta-HPV has not been studied in human keratinocytes. We now provide evidence that beta-HPV8 and 38 are transcriptionally active in human keratinocytes. Inactivation of the viral E8^E2 repressor protein greatly increases genome replication and transcription of the E6 and E7 oncogenes, but surprisingly, this does not result in immortalization of keratinocytes. Differentiation of HPV8- or HPV38-transfected keratinocytes in organotypic cultures induces transcripts encoding the L1 capsid gene, suggesting that productive replication is initiated. This indicates that human keratinocytes are suited as a model to investigate beta-HPV replication.

Vaccination with human alphapapillomavirus-derived L2 multimer protects against human betapapillomavirus challenge, including in epidermodysplasia verruciformis model mice

Human alphapapillomaviruses (αHPV) infect genital mucosa, and a high-risk subset is a necessary cause of cervical cancer. Licensed L1 virus-like particle (VLP) vaccines offer immunity against the nine most common αHPV associated with cervical cancer and genital warts. However, vaccination with an αHPV L2-based multimer vaccine, α11-88x5, protected mice and rabbits from vaginal and skin challenge with diverse αHPV types. While generally clinically inapparent, human betapapillomaviruses (βHPV) are possibly associated with cutaneous squamous cell carcinoma (CSCC) in epidermodysplasia verruciformis (EV) and immunocompromised patients. Here we show that α11-88x5 vaccination protected wild type and EV model mice against HPV5 challenge. Passive transfer of antiserum conferred protection independently of Fc receptors (FcR) or Gr-1+ phagocytes. Antisera demonstrated robust antibody titers against ten βHPV by L1/L2 VLP ELISA and neutralized and protected against challenge by 3 additional βHPV (HPV49/76/96). Thus, unlike the licensed vaccines, α11-88x5 vaccination elicits broad immunity against αHPV and βHPV.

From rare disorders of immunity to common determinants of infection: Following the mechanistic thread

The immense interindividual clinical variability during any infection is a long-standing enigma. Inborn errors of IFN-γ and IFN-α/β immunity underlying rare infections with weakly virulent mycobacteria and seasonal influenza virus have inspired studies of two common infections: tuberculosis and COVID-19. A TYK2 genotype impairing IFN-γ production accounts for about 1% of tuberculosis cases, and autoantibodies neutralizing IFN-α/β account for about 15% of critical COVID-19 cases. The discovery of inborn errors and mechanisms underlying rare infections drove the identification of common monogenic or autoimmune determinants of related common infections. This "rare-to-common" genetic and mechanistic approach to infectious diseases may be of heuristic value.

Defects of the Innate Immune System and Related Immune Deficiencies

The innate immune system is the host's first line of defense against pathogens. Toll-like receptors (TLRs) are pattern recognition receptors that mediate recognition of pathogen-associated molecular patterns. TLRs also activate signaling transduction pathways involved in host defense, inflammation, development, and the production of inflammatory cytokines. Innate immunodeficiencies associated with defective TLR signaling include mutations in NEMO, IKBA, MyD88, and IRAK4. Other innate immune defects have been associated with susceptibility to herpes simplex encephalitis, viral infections, and mycobacterial disease, as well as chronic mucocutaneous candidiasis and epidermodysplasia verruciformis. Phagocytes and natural killer cells are essential members of the innate immune system and defects in number and/or function of these cells can lead to recurrent infections. Complement is another important part of the innate immune system. Complement deficiencies can lead to increased susceptibility to infections, autoimmunity, or impaired immune complex clearance. The innate immune system must work to quickly recognize and eliminate pathogens as well as coordinate an immune response and engage the adaptive immune system. Defects of the innate immune system can lead to failure to quickly identify pathogens and activate the immune response, resulting in susceptibility to severe or recurrent infections.

HPV-Related Skin Phenotypes in Patients with Inborn Errors of Immunity

Patients with inborn errors of immunity (IEI) are prone to develop infections, either due to a broad spectrum of pathogens or to only one microbe. Since skin is a major barrier tissue, cutaneous infections are among the most prevalent in patients with IEI due to high exposures to many microbes. In the general population, human papillomaviruses (HPVs) cause asymptomatic or self-healing infections, but, in patients with IEI, unusual clinical expression of HPV infection is observed ranging from epidermodysplasia verruciformis (EV) (a rare disease due to β-HPVs) to profuse, persistent, and recalcitrant warts (due to α-, γ-, and μ-HPVs) or even tree man syndrome (due to HPV2). Mutations in EVER1, EVER2, and CIB1 are associated with EV phenotype; GATA2, CXCR4, and DOCK8 mutations are typically associated with extensive HPV infections, but there are several other IEI that are less frequently associated with severe HPV lesions. In this review, we describe clinical, immunological, and genetic patterns of IEI related to severe HPV cutaneous infections and propose an algorithm for diagnosis of IEI with severe warts associated, or not, with lymphopenia.

RG2-VLP: a Vaccine Designed to Broadly Protect against Anogenital and Skin Human Papillomaviruses Causing Human Cancer

The family of human papillomaviruses (HPV) includes over 400 genotypes. Genus α genotypes generally infect the anogenital mucosa, and a subset of these HPV are a necessary, but not sufficient, cause of cervical cancer. Of the 13 high-risk (HR) and 11 intermediate-risk (IR) HPV associated with cervical cancer, genotypes 16 and 18 cause 50% and 20% of cases, respectively, whereas HPV16 dominates in other anogenital and oropharyngeal cancers. A plethora of βHPVs are associated with cutaneous squamous cell carcinoma (CSCC), especially in sun-exposed skin sites of epidermodysplasia verruciformis (EV), AIDS, and immunosuppressed patients. Licensed L1 virus-like particle (VLP) vaccines, such as Gardasil 9, target a subset of αHPV but no βHPV. To comprehensively target both α- and βHPVs, we developed a two-component VLP vaccine, RG2-VLP, in which L2 protective epitopes derived from a conserved αHPV epitope (amino acids 17 to 36 of HPV16 L2) and a consensus βHPV sequence in the same region are displayed within the DE loop of HPV16 and HPV18 L1 VLP, respectively. Unlike vaccination with Gardasil 9, vaccination of wild-type and EV model mice (Tmc6Δ/Δ or Tmc8Δ/Δ) with RG2-VLP induced robust L2-specific antibody titers and protected against β-type HPV5. RG2-VLP protected rabbits against 17 αHPV, including those not covered by Gardasil 9. HPV16- and HPV18-specific neutralizing antibody responses were similar between RG2-VLP- and Gardasil 9-vaccinated animals. However, only transfer of RG2-VLP antiserum effectively protected naive mice from challenge with all βHPVs tested. Taken together, these observations suggest RG2-VLP's potential as a broad-spectrum vaccine to prevent αHPV-driven anogenital, oropharyngeal, and βHPV-associated cutaneous cancers. IMPORTANCE Licensed preventive HPV vaccines are composed of VLPs derived by expression of major capsid protein L1. They confer protection generally restricted to infection by the αHPVs targeted by the up-to-9-valent vaccine, and their associated anogenital cancers and genital warts, but do not target βHPV that are associated with CSCC in EV and immunocompromised patients. We describe the development of a two-antigen vaccine protective in animal models against known oncogenic αHPVs as well as diverse βHPVs by incorporation into HPV16 and HPV18 L1 VLP of 20-amino-acid conserved protective epitopes derived from minor capsid protein L2.

Genomics Driving Diagnosis and Treatment of Inborn Errors of Immunity With Cancer Predisposition

Inborn errors of immunity (IEI) are genetically and clinically heterogeneous disorders that, in addition to infection susceptibility and immune dysregulation, can have an enhanced cancer predisposition. The increasing availability of upfront next-generation sequencing diagnostics in immunology and oncology have uncovered substantial overlap of germline and somatic genetic conditions that can result in immunodeficiency and cancer. However, broad application of unbiased genetics in these neighboring disciplines still needs to be deployed, and joined therapeutic strategies guided by germline and somatic genetic risk factors are lacking. We illustrate the current difficulties encountered in clinical practice, summarize the historical development of pathophysiological concepts of cancer predisposition, and review select genetic, molecular, and cellular mechanisms of well-defined and illustrative disease entities such as DNA repair defects, combined immunodeficiencies with Epstein-Barr virus susceptibility, autoimmune lymphoproliferative syndromes, regulatory T-cell disorders, and defects in cell intrinsic immunity. We review genetic variants that, when present in the germline, cause IEI with cancer predisposition but, when arising as somatic variants, behave as oncogenes and cause specific cancer entities. We finally give examples of small molecular compounds that are developed and studied to target genetically defined cancers but might also proof useful to treat IEI.

The Pathogenesis of Giant Condyloma Acuminatum (Buschke-Lowenstein Tumor): An Overview

Giant condyloma acuminatum, also known as Buschke-Lowenstein tumor (BLT), is a rare disease of the anogenital region. BLT is considered a locally aggressive tumor of benign histological appearance, but with the potential for destructive growth and high recurrence rates. BLT development is strongly associated with infection with low-risk human papillomaviruses (HPVs), mostly HPV-6 and -11. Immunity to HPVs plays a crucial role in the natural control of various HPV-induced lesions. Large condyloma acuminata are frequently reported in patients with primary (e.g., DOCK8 or SPINK5 deficiencies) and secondary (e.g., AIDS, solid organ transplantation) immune defects. Individuals with extensive anogenital warts, including BLT in particular, should therefore be tested for inherited or acquired immunodeficiency. Research into the genetic basis of unexplained cases is warranted. An understanding of the etiology of BLT would lead to improvements in its management. This review focuses on the role of underlying HPV infections, and human genetic and immunological determinants of BLT.

Restriction of viral gene expression and replication prevents immortalization of human keratinocytes by a beta-human papillomavirus

High-risk (HR) human papillomaviruses (HPV) from the genus alpha cause anogenital and oropharyngeal cancers, whereas the contribution of HPV from the genus beta to the development of cutaneous squamous cell cancer is still under debate. HR-HPV genomes display potent immortalizing activity in human keratinocytes, the natural target cell for HPV. This paper shows that immortalization of keratinocytes by the beta-HPV49 genome requires the inactivation of the viral E8^E2 repressor protein and the presence of the E6 and E7 oncoproteins but also of the E1 and E2 replication proteins. This reveals important differences in the carcinogenic properties of HR-HPV and beta-HPV but also warrants further investigations on the distribution and mutation frequencies of beta-HPV in human cancers.

Beta-human papillomaviruses (HPV) have been implicated in the development of cutaneous squamous cell cancer (cSCC) in epidermodysplasia verruciformis (EV) patients and organ transplant recipients. In contrast to high-risk (HR) HPV, which cause anogenital and oropharyngeal cancers, immortalizing activity of complete beta-HPV genomes in normal human keratinocytes (NHK), the natural target cells for HPV, has not been reported. We now demonstrate that the beta-HPV49 wild-type genome is transcriptionally active in NHK but lacks immortalizing activity unless the E8 gene, which encodes the E8^E2 repressor, is inactivated. HPV49 E8− immortalized keratinocytes maintain high levels of viral gene expression and very high copy numbers of extrachromosomal viral genomes during long-term cultivation. Not only disruption of the viral E6 and E7 oncogenes but also of the E1 or E2 replication genes renders E8− genomes incapable of immortalization. E8−/E1− and E8−/E2− genomes display greatly reduced E6 and E7 RNA levels in short-term assays. This strongly suggests that high-level expression of E6 and E7 from extrachromosomal templates is necessary for immortalization. The requirement for an inactivation of E8 while maintaining E1 and E2 expression highlights important differences in the carcinogenic properties of HR-HPV and beta-HPV. These findings strengthen the notion that beta-HPV have carcinogenic potential that warrants further investigations into the distribution of beta-HPV in human cancers.

Case Report: Altered NK Cell Compartment and Reduced CXCR4 Chemotactic Response of B Lymphocytes in an Immunodeficient Patient With HPV-Related Disease

The study of inborn errors of immunity (IEI) provides unique opportunities to elucidate the microbiome and pathogenic mechanisms related to severe viral infection. Several immunological and genetic anomalies may contribute to the susceptibility to develop Human Papillomavirus (HPV) pathogenesis. They include different acquired immunodeficiencies, EVER1-2 or CIB1 mutations underlying epidermodysplasia verruciformis (EV) syndrome and multiple IEI. Whereas EV syndrome patients are specifically unable to control infections with beta HPV, individuals with IEI show broader infectious and immune phenotypes. The WHIM (warts, hypogammaglobulinemia, infection, and myelokathexis) syndrome caused by gain-of-CXCR4-function mutation manifests by HPV-induced extensive cutaneous warts but also anogenital lesions that eventually progress to dysplasia. Here we report alterations of B and NK cells in a female patient suffering from cutaneous and mucosal HPV-induced lesions due to an as-yet unidentified genetic defect. Despite no detected mutations in CXCR4, B but not NK cells displayed a defective CXCR4-dependent chemotactic response toward CXCL12. In addition, NK cells showed an abnormal distribution with an expanded CD56^bright cell subset and defective cytotoxicity of CD56^dim cells. Our observations extend the clinical and immunological spectrum of IEI associated with selective susceptibility toward HPV pathogenesis, thus providing new insight on the immune control of HPV infection and potential host susceptibility factors.

Consideration of underlying immunodeficiency in refractory or recalcitrant warts: A review of the literature

Although the exact mechanisms have yet to be elucidated, it is clear that cellular immunity plays a role in clearance of human papillomavirus (HPV) infections as it relates to the development of warts. Patients with extensive, recalcitrant, or treatment‐refractory warts may have an underlying immune system impairment at the root of HPV susceptibility. Early recognition of genetic disorders associated with immunologic defects that allow for recalcitrant HPV infection may expedite appropriate treatment for patients. Early recognition is often pivotal in preventing subsequent morbidity and/or mortality that may arise from inborn errors of immunity, such as WHIM (Warts, Hypogammaglobulinemia, Infections, Myelokathexis) syndrome. Among these, cervical cancer is one of the most common malignancies associated with HPV, can be fatal if not treated early, and is seen more frequently in patients with underlying immune deficiencies. A review of diseases with susceptibility to HPV provides clues to understanding the pathophysiology of warts. We also present diagnostic guidance to facilitate the recognition of inborn errors of immunity in patients with extensive and/or recalcitrant HPV infections.

Genetic susceptibility to viral disease in humans

BACKGROUND

During the past decades studies on patients with severe viral infections have revealed rare inborn errors of immunity (IEI) underlying these diseases. This has led to important new insights into the molecular genetics and immunological mechanisms underlying susceptibility to viral infection in humans.

OBJECTIVES

Here the current knowledge on major IEI predisposing to severe or chronic viral infection are described and discussed, and the clinical implications of these findings for individualized prophylaxis and treatment are outlined.

SOURCES

The review is based on a broad literature search including relevant studies primarily based studies in patients, supported by experimental molecular models in vitro or in mice to characterize pathophysiological mechanism governing these disease conditions.

CONTENT

Current concepts and principles of genetic predisposition to viral infections in humans are described with a major focus on defects related to innate immune responses and new concepts of constitutive immune mechanisms. The topic therefore spans from seminal studies on the human genetics of herpesvirus infections in the central nervous system, severe influenza, and disease following vaccination with live attenuated viral vaccines, and finally mentioning genetic resistance to viral infection.

IMPLICATIONS

Past and present studies in patients with IEI conferring vulnerability to viral infections have taught us important lessons on protective innate and adaptive antiviral immunity in humans. Such knowledge also has important clinical implications allowing development of prophylactic and therapeutic solutions to prevent or dampen the clinical consequences of insufficient or dysregulated antiviral immunity in patients. Collectively, such measures are likely to improve patient management at an individualized level and also help societies reduce disease burden from viral infections.

Cutaneous Squamous Cell Carcinoma: The Frontier of Cancer Immunoprevention

Cutaneous squamous cell carcinoma (cSCC) is the second most common cancer, with its incidence rising steeply. Immunosuppression is a well-established risk factor for cSCC, and this risk factor highlights the critical role of the immune system in regulating cSCC development and progression. Further highlighting the nature of cSCC as an immunological disorder, substantial evidence demonstrates a tight association between cSCC risk and age-related immunosenescence. Besides the proven efficacy of immune checkpoint blockade therapy for advanced cSCC, novel immunotherapy that targets cSCC precursor lesions has shown efficacy for cSCC prevention. Furthermore, the appreciation of the interplay between keratinocytes, commensal papillomaviruses, and the immune system has revealed the possibility for the development of a preventive cSCC vaccine. cSCC shares fundamental aspects of its origin and pathogenesis with mucosal SCCs. Therefore, advances in the field of cSCC immunoprevention will inform our approach to the management of mucosal SCCs and potentially other epithelial cancers.

New primary immunodeficiencies 2021 context and future

PURPOSE OF REVIEW

Primary immunodeficiency diseases (PIDs), also called inborn errors of immunity (IEI), are genetic disorders classically characterized by an increased susceptibility to infection and/or disruption in the regulation of an immunologic pathway. This review summarizes and highlights the new IEI disorders in the IUIS 2019 report and 2020 interim report and discusses the directions for the future management of PIDs.

RECENT FINDINGS

Since 2017, the International Union of Immunologic Societies (IUIS) IEI committee has updated the IUIS classification of IEIs with 88 new gene defects and 75 new immune disorders. The increased utilization of genetic testing and advances in the strategic evaluation of genetic variants have identified, not only novel IEI disorders, but additional genetic causes for known IEI disorders. Investigation of potential immune susceptibilities during the ongoing COVID-19 pandemic suggests that defects in Type I interferon signalling may underlie more severe disease.

SUMMARY

The rapid discovery of new IEIs reflects the growing trend of applying genetic testing modalities as part of medical diagnosis and management.In turn, elucidating the pathophysiology of these novel IEIs have enhanced our understanding of how genetic mutations can modulate the immune system and their consequential effect on human health and disease.

Recalcitrant Warts, Epidermodysplasia Verruciformis, and the Tree-Man Syndrome: Phenotypic Spectrum of Cutaneous Human Papillomavirus Infections at the Intersection of Genetic Variability of Viral and Human Genomes

Human papillomavirus (HPV) infections can cause common warts, which usually resolve spontaneously or become recalcitrant, resistant to multiple treatments. In rare cases, they transform into cutaneous giant horns resulting in the tree-man syndrome (TMS). Defective β-HPVs can cause flat warts in epidermodysplasia verruciformis (EV), a genetic disorder. In typical EV, limited to the skin, the mutated genes are critical for keratinocyte-intrinsic immunity, whereas atypical, syndromic EV involves genes controlling T cells. Inborn errors of immunity due to mutations in distinct genes underlying recalcitrant warts and the α-HPV2‒driven TMS have been identified, all disrupting T-cell immunity. Collectively, these observations attest to the wide phenotypic spectrum of cutaneous infections caused by different HPV types at the intersection of the genetic diversity of the viral and human genomes.

Mechanisms of viral inflammation and disease in humans

[Figure: see text].

Risk of penile tumor development in Caucasian individuals is independent of the coding variant rs7208422 in the TMC8 (EVER2) gene

Genetic variation in the transmembrane channel-like (TMC)6/TMC8 region has been linked to β-type human papillomavirus (HPV) infection and squamous cell carcinoma (SCC) of the skin and the head and neck, α-type HPV persistence and progression to cervical cancer. The functional variant rs7208422 of the TMC8 gene was suggested to have a high impact on susceptibility to β-papillomaviruses and their oncogenic potential and to also have an influence on α-type HPV-related disease. The aim of the present study was to evaluate a possible influence of rs7208422 on penile cancer risk, a known α-type HPV-related malignancy. Therefore, the distribution of rs7208422 was determined by direct Sanger sequencing of 104 Caucasian penile SCC cases and compared to data of 3,810 controls taken from the literature. HPV detection was performed by usage of GP5+/6+ primers and subtype-specific PCR. It was observed that the distribution of rs7208422 followed the Hardy-Weinberg equilibrium in both cases and controls. HPV DNA was detected in 39% of the penile SCC cases. Overall, there was no significant difference in the distribution of rs7208422 neither between cases and controls (P=0.726) nor between HPV-positive and -negative penile SCC cases (P=0.747). There was also no association between rs7208422 genotypes and age of disease onset (P=0.740). In conclusion, the present data argue against a significant impact of rs7208422 on the risk for the development of penile SCC in Caucasians. Even in combination with the HPV status, the SNP appears not to influence the risk of penile SCC in HPV-positive cases.

Human genetic and immunological dissection of papillomavirus-driven diseases: new insights into their pathogenesis

Human papillomaviruses (HPVs) are responsible for cutaneous and mucosal lesions. Persistent HPV infection remains a leading cause of uterine cancer in women, but also of cutaneous squamous cell carcinoma in patients with epidermodysplasia verruciformis (EV), and of rare and devastating benign tumors, such as 'tree-man' syndrome. HPV infections are usually asymptomatic or benign in the general population. Severe manifestations in otherwise healthy subjects can attest to inherited immunodeficiencies. The human genetic dissection of these cases has identified critical components of the immune response to HPVs, including the non-redundant roles of keratinocyte-intrinsic immunity in controlling β-HPVs, and of T cell-dependent adaptive immunity for controlling all HPV types. A key role of the CD28 T-cell costimulation pathway in controlling common warts due to HPVs was recently discovered. This review summarizes the state of the art in the human genetics of HPV infection, focusing on two key affected cell types: keratinocytes and T cells.

Herpes simplex encephalitis in a patient with a distinctive form of inherited IFNAR1 deficiency

Inborn errors of TLR3-dependent IFN-α/β- and IFN-λ-mediated immunity in the CNS can underlie herpes simplex virus 1 (HSV-1) encephalitis (HSE). The respective contributions of IFN-α/β and IFN-λ are unknown. We report a child homozygous for a genomic deletion of the entire coding sequence and part of the 3'-UTR of the last exon of IFNAR1, who died of HSE at the age of 2 years. An older cousin died following vaccination against measles, mumps, and rubella at 12 months of age, and another 17-year-old cousin homozygous for the same variant has had other, less severe, viral illnesses. The encoded IFNAR1 protein is expressed on the cell surface but is truncated and cannot interact with the tyrosine kinase TYK2. The patient's fibroblasts and EBV-B cells did not respond to IFN-α2b or IFN-β, in terms of STAT1, STAT2, and STAT3 phosphorylation or the genome-wide induction of IFN-stimulated genes. The patient's fibroblasts were susceptible to viruses, including HSV-1, even in the presence of exogenous IFN-α2b or IFN-β. HSE is therefore a consequence of inherited complete IFNAR1 deficiency. This viral disease occurred in natural conditions, unlike those previously reported in other patients with IFNAR1 or IFNAR2 deficiency. This experiment of nature indicates that IFN-α/β are essential for anti-HSV-1 immunity in the CNS.