Antibody response to a synthetic peptide derived from the human papillomavirus type 6/11 L2 protein in recurrent respiratory papillomatosis: correlation between Southern blot hybridization, polymerase chain reaction, and serology

In RRP, serologic response to HPV is frequently absent and slow to develop

Background

Recurrent respiratory papillomatosis (RRP) is characterized by repeated formation of papillomas in the respiratory tract and is caused by human papillomavirus (HPV) types 6 and 11. Women with genital HPV infection are slow to develop weak humoral immunity, but respond robustly to the HPV vaccine. We wondered if people with RRP had a similar immune response.

Methods

A convenience cross-sectional sample of patients with RRP were recruited into one of four groups: 1) adults and adolescents with active RRP, 2) children with active RRP, 3) RRP patients who had undergone HPV vaccination prior to enrollment and, 4) people with RRP who were in remission. Anti-HPV6 and HPV11 serology was determined by cLIA on a single blood draw.

Results

Of the 70 subjects enrolled, 36, 16, 8, and 10, were in groups 1, 2, 3, and 4, respectively. 47% of participants aged >11 years and 81% aged ≤11 years possessed no antibodies against HPV6 or HPV11 (ie. double seronegative). 61% of patients in remission were double seronegative. All participants who had received HPV vaccine previously were seropositive to at least one of these low risk HPV types (ie none of them were double seronegative). Among patients who had active RRP and never had HPV vaccination (n = 52) there was an association between duration of symptoms and seropositivity. Of those who were seropositive, the geometric mean duration of symptoms was 11 years compared to 4.7 years for those who were seronegative (p = 0.001).

Conclusion

People with RRP are capable of developing a humoral response to HPV6 and HPV11. That response appears to be robust when initiated by the HPV vaccine, but either nonexistent or slow to develop in response to infection. Most in remission do not have demonstrable antibody levels against HPV6 or HPV11.

Immunological tolerance of low-risk HPV in recurrent respiratory papillomatosis

Recurrent respiratory papillomatosis (RRP) is characterized by benign exophytic lesions of the respiratory tract caused by the human papillomavirus (HPV), in particular low-risk HPV6 and HPV11. Aggressiveness varies greatly among patients. Surgical excision is the current standard of care for RRP, with adjuvant therapy used when surgery cannot control disease recurrence. Numerous adjuvant therapies have been used to control RRP with some success, but none are curative. Current literature supports a polarization of the adaptive immune response to a T helper type 2 (Th2)-like or T regulatory phenotype, driven by a complex interplay between innate immunity, adaptive immunity and HPV6/11 proteins. Additionally, certain immunogenetic polymorphisms can predispose individuals to an HPV6/11-tolerant microenvironment. As a result, immunomodulatory efforts are being made to restore the host immune system to a more balanced T cell phenotype and clear viral infection. Literature has shown exciting evidence for the role of HPV vaccination with Gardasil or Gardasil-9 as both primary prevention, by decreasing incidence through childhood vaccinations, and secondary prevention, by treating active RRP disease. Multi-institution randomized clinical trials are needed to better assess their efficacy as treatment for active disease. Interestingly, a DNA vaccine has recently shown in-vitro success in generating a more robust CD8⁺ T cell response. Furthermore, clinical trials for programmed death 1 (PD-1) inhibitors are under investigation for RRP management. Molecular insights into RRP, in particular the interplay between RRP and the immune system, are needed to advance our understanding of this disease and may lead to the identification of immunomodulatory agents to better manage RRP.

Genetic dysregulation in recurrent respiratory papillomatosis

OBJECTIVES/HYPOTHESIS

Recurrent respiratory papillomatosis (RRP) is a devastating disease, caused by infection of the upper aerodigestive tract with human papillomavirus types 6 and 11. There is no cure for RRP, and surgical removal is the mainstay of treatment. The purpose of this project was to compare genes of cell cycle, apoptosis, and inflammatory cytokines in laryngeal papilloma versus normal tissue for a better understanding of the molecular mechanisms of the disease to discover novel therapies.

STUDY DESIGN

Basic science research study.

METHODS

Papilloma tissue was obtained from patients requiring surgical debridement. For comparison, normal mucosa was obtained from the excised uvula of patients undergoing uvulopalatopharyngoplasty. Total RNA was extracted from both groups and then probed using customized reverse transcriptase real time polymerase chain reaction gene arrays.

RESULTS

The custom arrays examine expression of 84 separate genes within the cell cycle, apoptosis, and inflammatory cytokine pathways. Our findings based on 11 papilloma samples run in comparison to normal mucosa shows that the MCL-1 gene of the apoptosis pathway is significantly downregulated. cytokine genes IL1-A, IL-8, IL-18, and IL-31 are also significantly dysregulated.

CONCLUSIONS

Genes of cell cycle and apoptosis are generally upregulated and downregulated, respectively, as expected in papilloma tissue, with MCL-1 achieving significance when compared to normal tissue. The finding of particular interest is that inflammatory cytokine genes were significantly downregulated, including IL1-A, IL-18, and IL-31. This finding may explain why patients infected with the virus are unable to mediate a T-cell immune clearance of their disease.

HPV associated with recurrent respiratory papillomatosis

Papillomaviruses are members of the Papillomaviridae family. Over 150 HPV types have been identified. Recurrent respiratory papillomatosis (RRP) is a chronic condition caused by HPV characterized by recurrent papillomas of the respiratory tract, mainly the larynx. During the early stages, the condition presents with hoarseness, while more advanced disease presents with stridor and respiratory distress. There is no specific cure and treatment consists of repeated surgical procedures to remove the papillomas. Most patients eventually go into remission, but some suffer for many years with this condition, which may be fatal. HPV-6 and HPV-11 are the HPV types most commonly associated with RRP. Although most studies have found RRP due to HPV-11 to be more aggressive than disease due to HPV-6, the variability in disease aggressiveness is probably multifactorial. Information regarding the current epidemiology, molecular diversity and host immune responses is important for strategizing ways to reduce disease. Data on HPV genotypes associated with RRP would provide valuable information for vaccination programs to reduce the incidence of these genotypes in mothers and, in the long term, reduce the incidence of RRP in children. This review focuses on HPV-6 and HPV-11 as the HPV types that cause RRP, and discusses the viral genome and replication, clinical presentation of RRP, current techniques of diagnosis and genotyping, and the molecular diversity of HPV-6 and HPV-11.

Recurrent respiratory papillomatosis: a complex defect in immune responsiveness to human papillomavirus-6 and -11

Recurrent respiratory papillomatosis (RRP) is a rare disease of the larynx caused by infection with human papillomaviruses (HPV) -6 or -11, associated with significant morbidity and on occasion mortality. Here we summarize our current understanding of the permissive adaptive and innate responses made by patients with RRP that support chronic HPV infection and prevent immune clearance of these viruses. Furthermore, we provide new evidence of T(H)2-like polarization in papillomas and blood of patients with RRP, restricted CD4 and CD8 Vbeta repertoires, the effect of HPV-11 early protein E6 on T-cell alloreactivity, enriched Langerhans cell presence in papillomas, and evidence that natural killer cells are dysfunctional in RRP. We review the immunogenetic mechanisms that regulate the dysfunctional responses made by patients with RRP in response to HPV infection of the upper airway. In addition, we are identifying T-cell epitopes on HPV-11 early proteins, in the context of human leukocyte antigen (HLA) class II alleles enriched in RRP that should help generate a therapeutic vaccine. Taken together, RRP is a complex, multigene disease manifesting as a tissue and HPV-specific, immune deficiency that prevents effective clearance and/or control of HPV-6 and -11 infection.

Treatment of severe laryngeal papillomatosis with intralesional injections of cidofovir [(S)-1-(3-hydroxy-2-phosphonylmethoxypropyl)cytosine]

Respiratory papillomatosis is a rare and often severe disease, usually localized in the larynx. It may cause respiratory distress and even life-threatening obstruction of the airways. Treatment is generally based on the evaporation of the lesions with a CO2 laser, but microsurgery, cytotoxic and/or cytostatic drugs, interferons, and vaccines are also used. Cidofovir [(S)-1-(3-hydroxy-2-phosphonylmethoxypropyl)cytosine] (HPMPC) was shown to suppress the growth of tumors induced by rabbit papillomavirus as well as human papillomavirus (HPV). The efficacy of cidofovir was assessed in 17 patients with severe respiratory papillomatosis. Cidofovir at a concentration of 2.5 mg/ml was injected directly in the different laryngeal papillomatous lesions during microlaryngoscopy under general anesthesia. Biopsies were taken before the treatment was started both for anatomopathology and viral typing. HPMPC kinetics in serum was monitored in three patients, the drug levels being determined by high-performance liquid chromatography. Complete disappearance of the papillomatosis was observed in 14 patients. Four patients relapsed and were successfully treated again with cidofovir. Of the three remaining patients, one progressed while under treatment with cidofovir, after an initial marked response. One patient had a partial remission and remained stable for more than 1 year after the last injection. He had a very aggressive and extensive disease originally. Finally, one patient was lost to follow-up after four injections. Intratumoral injections of cidofovir for the treatment of severe laryngeal papillomatosis is a powerful new therapeutic approach for this disease. Treatment was well tolerated, and no significant side effects were noted.

Demonstration of antibodies against human papillomavirus type-11 E6 and L2 proteins in patients with recurrent respiratory papillomatosis

Recurrent respiratory papillomatosis (RRP) is highly prevalent in Thailand, with the human papillomavirus (HPV) type-11 being the most widespread. In this study, we isolated the HPV type-11 (HPV-11) genome from subjects with RRP and subcloned the E6 and L2 open reading frames (ORFs) with the expression vectors pEX1 and pEX3. The recombinant E6/beta-gal and L2/beta-gal fusion proteins were expressed in E. coli. Using the recombinant proteins, we demonstrated the presence of antibodies against HPV-11 E6 and L2 in RRP patients by Western blot analysis. The prevalence of seropositivity for HPV-11 E6 and L2 were 5% (1/20) and 10% (2/20), respectively. Although RRP is caused by infection on the mucosal surface, it appears that an immune response occurs against viral proteins expressed in the epithelial lesions.

Prognostic value of clinical findings in histologically verified adult-onset laryngeal papillomas

A retrospective study of adult-onset laryngeal papilloma was performed to clarify whether any clinical features at the time of diagnosis could predict its course. All patients had a histologically confirmed diagnosis of laryngeal papillomas and were treated at Helsinki University Hospital between 1975 and 1994. Those with adult-onset disease and follow-up exceeding 1 year (n = 74) entered the study. Based on the case records surveyed, results suggested two risk factors for frequent laryngeal procedures: young age at onset of papilloma and a lesion extending to the anterior third to the vocal folds. It was not possible to predict the course of the disease by such clinical findings as symptoms or size or number of primary papilloma lesions. As regards the recurrence of disease, the classic division of adult-onset laryngeal papilloma into solitary and multiple type was not found to be clinically relevant.

Human papillomavirus (HPV) type distribution and serological response to HPV type 6 virus-like particles in patients with genital warts

Thirty-nine patients with condylomas (12 women and 27 men) attending a dermatology clinic were tested for genital human papillomavirus (HPV) DNA and for seroprevalence to HPV type 6 (HPV6) L1 virus-like particles. The L1 consensus PCR system (with primers MY09 and MY11) was used to determine the presence and types of HPV in sample specimens. All 37 (100%) patients with sufficient DNA specimens were positive for HPV DNA, and 35 (94%) had HPV6 DNA detected at the wart site. Three patients (8%) had HPV11 detected at the wart site, and one patient had both HPV6 and -11 detected at the wart site. Thirteen additional HPV types were detected among the patients; the most frequent were HPV54 (8%) and HPV58 (8%). Baculovirus-expressed HPV6 L1 virus-like particles were used in enzyme-linked immunosorbent assays to determine seroprevalence among the patients with warts. Seronegativity was defined by a control group of 21 women who were consistently PCR negative for HPV DNA. Seroprevalence was also determined for reference groups that included cytologically normal women who had detectable DNA from either HPV6 or HPV16 and women with HPV16-associated cervical intraepithelial neoplasia. Among the asymptomatic women with HPV6, only 2 of 9 (22%) were seropositive, compared with 12 of 12 (100%) female patients with warts. A similar trend in increased HPV6 seropositivity with increased grade of disease was found with the HPV16 DNA-positive women, whose seroprevalence increased from 1 in 11 (9%) in cytologically normal women to 6 in 15 (40%) among women with cervical intraepithelial neoplasia 1 or 3. However, only 4 of 25 (16%) male patients were seropositive. No factors examined, such as age, sexual behavior, or a history of warts, were found to definitively account for the gender difference in seroresponse.