Comèl-Netherton syndrome complicated by papillomatous skin lesions containing human papillomaviruses 51 and 52 and plane warts containing human papillomavirus 16

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 dissection of papillomavirus-driven diseases: new insight into their pathogenesis

Human papillomaviruses (HPVs) infect mucosal or cutaneous stratified epithelia. There are 5 genera and more than 200 types of HPV, each with a specific tropism and virulence. HPV infections are typically asymptomatic or result in benign tumors, which may be disseminated or persistent in rare cases, but a few oncogenic HPVs can cause cancers. This review deals with the human genetic and immunological basis of interindividual clinical variability in the course of HPV infections of the skin and mucosae. Typical epidermodysplasia verruciformis (EV) is characterized by β-HPV-driven flat wart-like and pityriasis-like cutaneous lesions and non-melanoma skin cancers in patients with inborn errors of EVER1-EVER2-CIB1-dependent skin-intrinsic immunity. Atypical EV is associated with other infectious diseases in patients with inborn errors of T cells. Severe cutaneous or anogenital warts, including anogenital cancers, are also driven by certain α-, γ-, μ or ν-HPVs in patients with inborn errors of T lymphocytes and antigen-presenting cells. The genetic basis of HPV diseases at other mucosal sites, such as oral multifocal epithelial hyperplasia or juvenile recurrent respiratory papillomatosis (JRRP), remains poorly understood. The human genetic dissection of HPV-driven lesions will clarify the molecular and cellular basis of protective immunity to HPVs, and should lead to novel diagnostic, preventive, and curative approaches in patients.

LEKTI domains D6, D7 and D8+9 serve as substrates for transglutaminase 1: implications for targeted therapy of Netherton syndrome

BACKGROUND

Transglutaminase (TG)1 plays a key role in the formation of the cornified envelope and thus in the maintenance of the epidermal barrier. Patients with Netherton syndrome (LEKTI deficiency) have increased activity of both TG1 and serin proteases.

OBJECTIVES

To determine whether there is a functional biochemical link between TG1 and LEKTI and whether LEKTI domains could possibly serve as substrates for TG1.

METHODS

We analysed the protein sequence of LEKTI for possible TG1 recognition sites using bioinformatics. Synthetic peptides and recombinant LEKTI domains D6, D7 and D8+9 were examined in vitro and in situ for possible substrate specificity. The recombinant LEKTI domains were studied for inhibitory activity in a kallikrein (KLK)5 activity test.

RESULTS

We identified possible TG1 consensus sequences in LEKTI domains D6, D7 and D8+9, pointing to a novel biological link between these two proteins. Indeed, synthesized short peptides from these consensus sequences were incorporated into the TG1 activity zone of the epidermis. In vitro the entire recombinant domains of LEKTI showed substrate specificity for TG1, which was again confirmed in situ. The inhibitory activity of the recombinant LEKTI domains was confirmed by a KLK5 inhibition test. The strongest inhibition was observed for domains D8+9.

CONCLUSIONS

There are specific domains of LEKTI that are recognized and processed by TG1. LEKTI domains D6, D7 and D8+9 contribute to the formation and protection of the cornified envelope. These results impact the development of protein replacement therapy approaches for Netherton syndrome. What's already known about this topic? LEKTI and transglutaminase (TG)1 are key proteins involved in the terminal differentiation of the epidermis. Lack of LEKTI causes Netherton syndrome; TG1 deficiency causes lamellar ichthyosis. The serine protease inhibitor LEKTI is processed into different functional units. Among different target proteases, kallikrein (KLK)5 appears to be a key player in disease pathology. It has been demonstrated that LEKTI domain 6 inhibits KLK5 and KLK7; LEKTI domains 8-11 also inhibit KLK14. What does this study add? The single LEKTI domains 6, 7 and the functional unit of domains 8 and 9 contain recognition motifs for TG1. We show that these domains and unit are crosslinked into the epidermis by TG1. Functional analyses of the recombinant LEKTI domains revealed that LEKTI D8+9 has the strongest inhibitory effect on KLK5. What is the translational message? The novel functional link between LEKTI and TG1 should be taken into account when considering the development of a targeted topical protein therapy for Netherton syndrome. The unit of domains D8+9 may be sufficient for this purpose.

Immune status, strain background, and anatomic site of inoculation affect mouse papillomavirus (MmuPV1) induction of exophytic papillomas or endophytic trichoblastomas

Papillomaviruses (PVs) induce papillomas, premalignant lesions, and carcinomas in a wide variety of species. PVs are classified first based on their host and tissue tropism and then their genomic diversities. A laboratory mouse papillomavirus, MmuPV1 (formerly MusPV), was horizontally transmitted within an inbred colony of NMRI-Foxn1(nu)/Foxn1nu (nude; T cell deficient) mice of an unknown period of time. A ground-up, filtered papilloma inoculum was not capable of infecting C57BL/6J wild-type mice; however, immunocompetent, alopecic, S/RV/Cri-ba/ba (bare) mice developed small papillomas at injection sites that regressed. NMRI-Foxn1(nu) and B6.Cg-Foxn1(nu), but not NU/J-Foxn1(nu), mice were susceptible to MmuPV1 infection. B6 congenic strains, but not other congenic strains carrying the same allelic mutations, lacking B- and T-cells, but not B-cells alone, were susceptible to infection, indicating that mouse strain and T-cell deficiency are critical to tumor formation. Lesions initially observed were exophytic papillomas around the muzzle, exophytic papillomas on the tail, and condylomas of the vaginal lining which could be induced by separate scarification or simultaneous scarification of MmuPV1 at all four sites. On the dorsal skin, locally invasive, poorly differentiated tumors developed with features similar to human trichoblastomas. Transcriptome analysis revealed significant differences between the normal skin in these anatomic sites and in papillomas versus trichoblastomas. The primarily dysregulated genes involved molecular pathways associated with cancer, cellular development, cellular growth and proliferation, cell morphology, and connective tissue development and function. Although trichoepitheliomas are benign, aggressive tumors, few of the genes commonly associated with basal cell carcinoma or squamous cells carcinoma were highly dysregulated.

Topical treatment of ichthyoses

Management of ichthyoses is a complex and continuously dynamic process. Primary treatments of ichthyosis are by means of topical moisturizers and topical medications. Patients and families need to have reasonable and realistic expectations when it comes to topical therapy. Topical medications cannot cure the scaling, but can gradually reduce it and thus improve their condition. No one treatment regimen works for everyone, and the best topical therapy for each patient may be the result of months (or years) of painstaking effort on both the physician's and the patient's behalf. As patients get older and their activities and lifestyles change, so should their topical treatment regimen. Bear in mind that the more complex the skin care regimen and costly the topical treatments, the less likely a patient and their family will be compliant.

Comèl-Netherton syndrome defined as primary immunodeficiency

BACKGROUND

Mutations in serine protease inhibitor Kazal-type 5 (SPINK5), encoding the serine protease inhibitor lympho-epithelial Kazal-type 5 related inhibitor (LEKTI), cause Comèl-Netherton syndrome, an autosomal-recessive disease characterized by congenital ichthyosis, bamboo hair, and atopic diathesis. Despite increased frequency of infections, the immunocompetence of patients with Comèl-Netherton syndrome has not been extensively investigated.

OBJECTIVE

To define Comèl-Netherton syndrome as a primary immunodeficiency disorder and to explore the benefit of intravenous immunoglobulin replacement therapy.

METHODS

We enrolled 9 patients with Comèl-Netherton syndrome, sequenced SPINK5, and analyzed LEKTI expression by immunohistochemistry. Immune function was assessed by measuring cognate immunity, serum cytokine levels, and natural killer cell cytotoxicity.

RESULTS

All patients presented with recurrent skin infections caused predominantly by Staphylococcus aureus. All but 1 reported recurrent respiratory tract infections; 78% had sepsis and/or pneumonia; 67% had recurrent gastrointestinal disease and failure to thrive. Mutations in SPINK5-including 6 novel mutations-were identified in 8 patients. LEKTI expression was decreased or absent in all patients. Immunologic evaluation revealed reduced memory B cells and defective responses to vaccination with Pneumovax and bacteriophage phiX174, characterized by impaired antibody amplification and class-switching. Immune dysregulation was suggested by a skewed T(h)1 phenotype and elevated proinflammatory cytokine levels, whereas serum concentrations of the chemokine (C-C motif) ligand 5 and natural killer cell cytotoxicity were decreased. Treatment with intravenous immunoglobulin resulted in remarkable clinical improvement and temporarily increased natural killer cell cytotoxicity.

CONCLUSION

These data provide new insights into the immunopathology of Comèl-Netherton syndrome and demonstrate that this multisystem disorder, characterized by lack of LEKTI expression in epithelial cells, is complicated by cognate and innate immunodeficiency that responds favorably to intravenous immunoglobulin therapy.

Early development of multiple epithelial neoplasms in Netherton syndrome

We report a case of Netherton syndrome manifested as congenital ichthyosiform erythroderma, trichorrhexis invaginata and atopy, who in early adulthood developed multiple, aggressive epithelial neoplasms in sun-exposed areas of the skin, in areas with papillomatous skin hyperplasia and at the left parotid region. The occurrence of cutaneous neoplasia has been reported in syndromes with congenital ichthyosis and suggests that the underlying genetic defects may cause the development of cancer in prone patients.

Human papillomavirus infection in Netherton's syndrome

BACKGROUND

Netherton's syndrome (NS) is a hereditary disorder with dermatological signs (e.g. ichthyosis) and a complex immunological dysfunction. In immunodeficient individuals human papillomavirus (HPV) types are associated with carcinomas on non-mucosal sites.

OBJECTIVES

To study the presence of HPV infection in different skin lesions of three male NS patients and to investigate a possible association between HPV and malignancies in NS.

METHODS

Patient 1 had extraordinary widespread multiple skin carcinomas on sunlight-exposed areas, as well as common viral warts. Patient 2 showed disseminated viral plane warts that resolved spontaneously, and patient 3 was free of skin lesions suspicious for HPV infection; only pseudoepitheliomatous wart-like lesions as a symptom of ichthyosis were apparent. We performed nested polymerase chain reaction analysis of DNA from benign and malignant skin lesions and HPV-8 serology in these three patients.

RESULTS

Antibodies to HPV-8 were not detectable in our patients; however, seven of 22 (31%) biopsies of the three NS patients were positive for HPV DNA. Epidermodysplasia verruciformis (EV) -associated HPV types and normal cutaneous types (HPV-2, HPV-28) were detected. Interestingly, only the patient with cutaneous carcinomas harboured, preferentially in malignant lesions, EV-HPV types (HPV-19, 23, 38 and HPV-RTRX9, closely related to EV-HPVs), whereas plane warts of patient 2 were positive for HPV-28. The pseudoepitheliomatous skin lesions were HPV-DNA negative in all investigated probes.

CONCLUSIONS

These data in NS patients further confirm an association of EV-HPVs with non-melanoma skin cancer (NMSC) and suggest a possible carcinogenic role similar to that assumed for NMSC in transplant recipients. A complex immunological disorder facilitating EV-HPV infection, negative HPV serology and photochemotherapy may all have contributed to the unusual occurrence of multiple cancers in one of our NS patients.