Natural history of human papillomavirus infection of sun-exposed healthy skin of immunocompetent individuals over three climatic seasons and identification of HPV209, a novel betapapillomavirus

Natural History of Incident and Persistent Cutaneous Human Papillomavirus and Human Polyomavirus Infections

BACKGROUND

Cutaneous human papillomaviruses (cuHPV) and polyomaviruses (HPyV) have been implicated in skin cancers; however, interpretation of findings across studies is complicated by limited understanding of the natural history of these infections across normal tissue types.

METHODS

In total, 675 eyebrow hair (EBH) and skin swab (SSW) samples were collected from 71 skin cancer screening patients every 6 months over 2 years and measured for presence of β-HPV, γ-HPV, and HPyV. Incidence, persistence, and clearance of cuHPV/HPyV were estimated, and risk factors associated with infection were examined.

RESULTS

Prevalence, incidence, and persistence of β-HPV, γ-HPV, and HPyV were consistently higher in SSW than in EBH, with types 5, 24, 49, 76 and Merkel cell polyomavirus (MCPyV) having incidence rates greater than 20 per 1000 person-months. Prevalent γ-HPV EBH infections persisted more often in women (P = .024), incident β-HPV EBH infections persisted less often among individuals with history of blistering sunburn (P = .019), and prevalent MCPyV SSW infections persisted more often in those with a history of skin cancer (P = .033).

CONCLUSIONS

Incidence and persistence of cuHPV/HPyV were observed in SSW and EBH; however, none of the risk factors examined were commonly associated with cuHPV/HPyV infections across normal tissue types.

The genetic diversity of human papillomavirus types from the species Gammapapillomavirus 15: HPV135, HPV146, and HPV179

Objectives

To determine the prevalence, viral load, tissue tropism, and genetic variability of novel human papillomavirus (HPV) type 179, which is etiologically associated with sporadic cases of common warts in immunocompromised patients, and phylogenetically related HPV types 135 and 146.

Methods

The representative collection of 850 HPV-associated clinical samples (oral/nasopharyngeal/anal, archival specimens of oral/oropharyngeal/conjunctival/cervical/skin cancer, benign lesions of the larynx/conjunctiva/skin, and eyebrows), obtained from immunocompetent individuals, was tested for the presence of HPV179, HPV135, and HPV146 using type-specific real-time PCRs. To assess the genetic diversity of the HPVs investigated in the non-coding long control region (LCR), several highly sensitive nested PCR protocols were developed for each HPV type. The genetic diversity of HPV179 was additionally determined in 12 HPV179 isolates from different anatomical sites of an only immunocompromised patient included in the study.

Results

HPV179, HPV135, and HPV146 were detected in 1.4, 2.0, and 1.5% of the samples tested, respectively, with no preference for cutaneous or mucosal epithelial cells. One (with five single nucleotide polymorphisms; SNPs), four (with one to six SNPs), and four (with one to eight SNPs) genetic variants of HPV179, HPV135, and HPV146, respectively, were identified among eligible samples. HPV179 isolates from the immunocompromised patient exhibited the identical LCR nucleotide sequence, suggesting that HPV179 can cause generalized HPV infections.

Conclusions

HPV179, HPV135, and HPV146 have a mucocutaneous tissue tropism and are associated with sporadic infections in immunocompromised and immunocompetent individuals. Because the majority of mutations were found outside the major functional domains of the respective LCRs, we assume that HPV179, HPV135, and HPV146 genetic variants pathogenically do not differ from their prototypes. In addition, no association was found between specific HPV179, HPV135, and HPV146 genetic variants and anatomical sites of infection and/or specific neoplasms.

Cutaneous viral infections associated with ultraviolet radiation exposure

The complex interplay between ultraviolet radiation (UVR) and cutaneous viral infections in the context of cancer etiology is challenging to unravel, given the limited information on the independent association between UVR and cutaneous viral infections. Using multiple biomarkers of infection with 24 types of cutaneous human papillomavirus (HPV) and 4 types of polyomaviruses (HPyV), we investigated cross-sectional associations with recent UVR exposure, using skin pigmentation measured by spectrophotometer. Age- and sex-adjusted associations between UVR and viral seropositivity, viral DNA present in eyebrow hairs (EBH) and skin swabs (SSW) were estimated using logistic regression. Beta-HPV seropositivity was associated with viral DNA positivity in EBH (OR = 1.40, 95% CI = 1.05-1.88) and SSW (OR = 1.86, 95% CI = 1.25-2.74). Similar associations were observed for Merkel cell polyomavirus. Participants in the highest tertile of UVR exposure were more likely to be seropositive for beta-HPV (OR = 1.81, 95% CI = 1.16-2.38), and have beta-HPV DNA in EBH (OR = 1.57, 95% CI = 1.06-2.33) and SSW (OR = 2.22, 95% CI = 1.25-3.96), compared to participants with the lowest tertile of UVR exposure. UVR exposure was positively associated with three different markers of beta-HPV infection. Therefore, future studies of HPV associated KC development should address more directly the role of HPV and UVR exposure as potential co-carcinogens.

A Preliminary Study of the Virome of the South American Free-Tailed Bats (Tadarida brasiliensis) and Identification of Two Novel Mammalian Viruses

Bats provide important ecosystem services as pollinators, seed dispersers, and/or insect controllers, but they have also been found harboring different viruses with zoonotic potential. Virome studies in bats distributed in Asia, Africa, Europe, and North America have increased dramatically over the past decade, whereas information on viruses infecting South American species is scarce. We explored the virome of Tadarida brasiliensis, an insectivorous New World bat species inhabiting a maternity colony in Rosario (Argentina), by a metagenomic approach. The analysis of five pooled oral/anal swab samples indicated the presence of 43 different taxonomic viral families infecting a wide range of hosts. By conventional nucleic acid detection techniques and/or bioinformatics approaches, the genomes of two novel viruses were completely covered clustering into the Papillomaviridae (Tadarida brasiliensis papillomavirus type 1, TbraPV1) and Genomoviridae (Tadarida brasiliensis gemykibivirus 1, TbGkyV1) families. TbraPV1 is the first papillomavirus type identified in this host and the prototype of a novel genus. TbGkyV1 is the first genomovirus reported in New World bats and constitutes a new species within the genus Gemykibivirus. Our findings extend the knowledge about oral/anal viromes of a South American bat species and contribute to understand the evolution and genetic diversity of the novel characterized viruses.

Assessing Gammapapillomavirus infections of mucosal epithelia with two broad-spectrum PCR protocols

Background

Human papillomaviruses (HPVs) have been divided into mucosal and cutaneous types according to their primary epithelial tissue tropism. However, recent studies showed the presence of several cutaneous types in mucosal lesions and healthy mucosa from different anatomical sites.

Methods

Here, the HPV prevalence and type-specific distribution were assessed in a variety of mucosal samples from 435 individuals using a combination of two established broad-spectrum primer systems: Gamma-PV PCR and CUT PCR.

Results

Overall HPV prevalence in anal canal swabs, cervical cancer biopsies, genital warts and oral swabs was 85, 47, 62 and 4%, respectively. In anal canal swabs, Alpha-PVs were most frequently found (59%), followed by Gamma- (37%) and Beta-PVs (4%). The prevalence and persistence of HPV infection in the anal canal of 226 individuals were further explored. Overall HPV, Gamma-PVs and multiple HPV infections were significantly higher in men vs. women (p = 0.034, p = 0.027 and p = 0.003, respectively); multiple HPV infections were more common in individuals ≤40 years (p = 0.05), and significantly higher prevalence of Gamma-PVs and multiple HPV infections was observed in HIV-1-positive vs. HIV-1-negative individuals (p = 0.003 and p = 0.04, respectively). Out of 21 patients with follow-up anal swabs, only one persistent infection with the same type (HPV58) was detected.

Conclusions

Our findings suggest that Gamma-PVs (except species Gamma-6) are ubiquitous viruses with dual muco-cutaneous tissue tropism. Anal canal Gamma-PV infections may be associated with sexual behavior and the host immune status. This study expands the knowledge on Gamma-PVs’ tissue tropism, providing valuable data on the characteristics of HPV infection in the anal canal.

Successful Treatment of Generalized Eruptive Keratoacanthoma of Grzybowski with Acitretin

Introduction

Keratoacanthomas (KA) are common cutaneous skin tumors originating from the hair follicles. Unlike squamous cell carcinoma, KA can regress spontaneously and have a benign evolution. Solitary KA is the most common form but familial multiple KA (Ferguson–Smith type), genetically predisposed KA (such as in xeroderma pigmentosum, or Muir–Torre syndrome), or sporadic multiple eruptive KA (Grzybowski type) have been described. Generalized eruptive KA of Grzybowski (GEKA) is a rare condition (around 40 reported cases). The pathophysiology is still unclear. Human papillomavirus (HPV) has been detected in sporadic KA but the presence of HPV39 has never been reported, to our knowledge, in GEKA.

Case Report

GEKA in an 80-year-old woman was successfully treated with acitretin (0.5 mg/kg/day) combined with surgical removal of the largest lesions. Treatment was well tolerated and led to decreased pruritus and tumor regression within 6 months. The presence of HPV39 was detected in a lesion by polymerase chain reaction and Sanger sequencing. No genetic alteration was found, in particular in the genes usually altered in squamous cell carcinoma (including NOTCH1, NOTCH2, CDKN2A, TP53).

Conclusion

We report a case of GEKA associated with the presence of HPV39 and the successful use of acitretin combined with surgical removal of the larger lesions.

High prevalence of Gammapapillomaviruses (Gamma-PVs) in pre-malignant cutaneous lesions of immunocompetent individuals using a new broad-spectrum primer system, and identification of HPV210, a novel Gamma-PV type

Genus Gammapapillomavirus (Gamma-PV) is the most diverse and largest clade within the Papillomaviridae family. A novel set of degenerate primers targeting the E1 gene was designed and further used in combination with the well-known CUT PCR assay to assess HPV prevalence and genus distribution in a variety of cutaneous samples from 448 immunocompetent individuals. General HPV, Gamma-PV and mixed infections prevalence were significantly higher in actinic keratosis with respect to benign and malignant neoplasms, respectively (p = 0.0047, p = 0.0172, p = 0.00001). Gamma-PVs were significantly more common in actinic keratosis biopsies than Beta- and Alpha-PVs (p = 0.002). The full-length genome sequence of a novel putative Gamma-PV type was amplified by 'hanging droplet' long-range PCR and cloned. The novel virus, designated HPV210, clustered within species Gamma-12. This study provides an additional tool enabling detection of HPV infections in skin and adds new insights about possible early roles of Gamma-PVs in the development of cutaneous malignant lesions.

HPV-47-Induced and Tattoo-associated Verrucae Planae: Report of a Case and Review of the Literature

The human papillomavirus (HPV), of which more than 200 different types have so far been identified, is an infectious disease impacting skin and mucous membranes. Several genera exist with distinct clinical impact. However, with ornamental tattoos increasing in popularity, a number of mostly cutaneous side effects have also been reported, such as infections, allergic reactions, or even a rise of malignant tumours within the tattoo. We report the first case of a β1-HPV-type infection in cutaneous lesions in terms of verrucae vulgares near a tattoo in an immunocompetent adult without pre-existing conditions, and discuss possible relationships and etiologic concerns of this association.