Comparative analysis of the neutralizing activity against SARS-CoV-2 Wuhan-Hu-1 strain and variants of concern: Performance evaluation of a pseudovirus-based neutralization assay.

Objectives: Emergence of new variants of SARS-CoV-2 might affect vaccine efficacy. Therefore, assessing the capacity of sera to neutralize variants of concern (VOCs) in BSL-2 conditions will help evaluating the immune status of population following vaccination or infection. Methods: Pseudotyped viruses bearing SARS-CoV-2 spike protein from Wuhan-Hu-1/D614G strains (wild type, WT), B.1.617.2 (Delta), or B.1.1.529 (Omicron) VOCs were generated to assess the neutralizing antibodies (nAbs) activity by a pseudovirus-based neutralization assay (PVNA). PVNA performance was assessed in comparison to the micro-neutralization test (MNT) based on live viruses. Sera collected from COVID-19 convalescents and vaccinees receiving mRNA (BNT16b2 or mRNA-1273) or viral vector (AZD1222 or Ad26.COV2.S) vaccines were used to measure nAbs elicited by two-dose BNT16b2, mRNA-1273, AZD1222 or one-dose Ad26.CO2.S, at different times from completed vaccination, ~ 1.5 month and ~ 4-6 months. Sera from pre-pandemic and unvaccinated individuals were analyzed as controls. Neutralizing activity following booster vaccinations against VOCs was also determined. Results: PVNA titers correlated with the gold standard MNT assay, validating the reliability of PVNA. Sera analyzed late from the second dose showed a reduced neutralization activity compared to sera collected earlier. Ad26.CO2.S vaccination led to very low or absent nAbs. Neutralization of Delta and Omicron BA.1 VOCs showed significant reduction of nAbs respect to WT strain. Importantly, booster doses enhanced Omicron BA.1 nAbs, with persistent levels at 3 months from boosting. Conclusions: PVNA is a reliable tool for assessing anti-SARS-CoV-2 nAbs helping the establishment of a correlate of protection and the management of vaccination strategies.

Safety and immune response kinetics of GRAd-COV2 vaccine: phase 1 clinical trial results.

Despite the successful deployment of efficacious vaccines and therapeutics, the development of novel vaccines for SARS-CoV-2 remains a major goal to increase vaccine doses availability and accessibility for lower income setting. We report here on the kinetics of Spike-specific humoral and T-cell response in young and old volunteers over 6 months follow-up after a single intramuscular administration of GRAd-COV2, a gorilla adenoviral vector-based vaccine candidate currently in phase-2 of clinical development. At all three tested vaccine dosages, Spike binding and neutralizing antibodies were induced and substantially maintained up to 3 months, to then contract at 6 months. Potent T-cell responses were readily induced and sustained throughout the study period, with only minor decline. No major differences in immune response to GRAd-COV2 vaccination were observed in the two age cohorts. In light of its favorable safety and immunogenicity, GRAd-COV2 is a valuable candidate for further clinical development and potential addition to the COVID-19 vaccine toolbox to help fighting SARS-CoV-2 pandemic.

Emulation of a Target Trial From Observational Data to Compare Effectiveness of Casirivimab/Imdevimab and Bamlanivimab/Etesevimab for Early Treatment of Non-Hospitalized Patients With COVID-19.

Objectives: Comparative analysis between different monoclonal antibodies (mAbs) against SARS-CoV-2 are lacking. We present an emulation trial from observational data to compare effectiveness of Bamlanivimab/Etesevimab (BAM/ETE) and Casirivimab/Imdevimab (CAS/IMD) in outpatients with early mild-to-moderate COVID-19 in a real-world scenario of variants of concern (VoCs) from Alpha to Delta. Methods: Allocation to treatment was subject to mAbs availability, and the measured factors were not used to determine which combination to use. Patients were followed through day 30. Viral load was measured by cycle threshold (CT) on D1 (baseline) and D7.Primary outcome was time to COVID-19-related hospitalization or death from any cause over days 0-30. Weighted pooled logistic regression and marginal structural Cox model by inverse probability weights were used to compare BAM/ETE vs. CAS/IMD. ANCOVA was used to compare mean D7 CT values by intervention. Models were adjusted for calendar month, MASS score and VoCs. We evaluated effect measure modification by VoCs, vaccination, D1 CT levels and enrolment period. Results: COVID19-related hospitalization or death from any cause occurred in 15 of 237 patients in the BAM/ETE group (6.3%) and in 4 of 196 patients in the CAS/IMD group (2.0%) (relative risk reduction [1 minus the relative risk] 72%; p=0.024). Subset analysis carried no evidence that the effect of the intervention was different across stratification factors. There was no evidence in viral load reduction from baseline through day 7 across the two groups (+0.17, 95% -1.41;+1.74, p=0.83). Among patients who experienced primary outcome, none showed a negative RT-PCR test in nasopharyngeal swab (p=0.009) and 82.4% showed still high viral load (p<0.001) on D7. Conclusions: In a pre-Omicron epidemiologic scenario, CAS/IMD reduced risk of clinical progression of COVID-19 compared to BAM/ETE. This effect was not associated with a concomitant difference in virological response.

Humoral and Cellular Immune Response Elicited by mRNA Vaccination Against Severe Acute Respiratory Syndrome Coronavirus 2 (SARS-CoV-2) in People Living With Human Immunodeficiency Virus Receiving Antiretroviral Therapy Based on Current CD4 T-Lymphocyte Count.

BACKGROUND: Data on SARS-CoV-2 vaccine immunogenicity in PLWH are currently limited. Aim of the study was to investigate immunogenicity according to current CD4 T-cell count. METHODS: PLWH on ART attending a SARS-CoV-2 vaccination program, were included in a prospective immunogenicity evaluation after receiving BNT162b2 or mRNA-1273. Participants were stratified by current CD4 T-cell count (poor CD4 recovery, PCDR: <200/mm3; intermediate CD4 recovery, ICDR: 200-500/mm3; high CD4 recovery, HCDR: >500/mm3). RBD-binding IgG, SARS-CoV-2 neutralizing antibodies (nAbs) and IFN-γ release were measured. As control group, HIV-negative healthcare workers (HCWs) were used. FINDINGS: Among 166 PLWH, after 1 month from the booster dose, detectable RBD-binding IgG were elicited in 86.7% of PCDR, 100% of ICDR, 98.7% of HCDR, and a neutralizing titre ≥1:10 elicited in 70.0%, 88.2%, and 93.1%, respectively. Compared to HCDR, all immune response parameters were significantly lower in PCDR. After adjusting for confounders, current CD4 T-cell <200/mm3 significantly predicted a poor magnitude of anti-RDB, nAbs and IFN-γ response. As compared with HCWs, PCDR elicited a consistently reduced immunogenicity for all parameters, ICDR only a reduced RBD-binding antibody response, whereas HCDR elicited a comparable immune response for all parameters. CONCLUSION: Humoral and cell-mediated immune response against SARS-CoV-2 were elicited in most of PLWH, albeit significantly poorer in those with CD4 T-cell <200/mm3 versus those with >500 cell/mm3 and HIV-negative controls. A lower RBD-binding antibody response than HCWs was also observed in PLWH with CD4 T-cell 200-500/mm3, whereas immune response elicited in PLWH with a CD4 T-cell >500/mm3 was comparable to HIV-negative population.

Parainfluenza viruses: A trigger for type 1 diabetes new onset?

Type 1 diabetes (T1DM) ethiopathogenesis is still being studied, since the role of environmental factors , especially viruses, is not yet clear. This study was conducted on 31 paediatric patients with T1DM at onset. We analysed: Coxsackieviruses A (CoxA), Coxsackieviruses B (CoxB), Echoviruses (Echo); Influenzavirus A and B (IV-A and IV-B); Adenovirus (AdV); Parainfluenza viruses 1-2 and 3 (PiV 1-2-3); Cytomegalovirus (CMV) and Respiratory Syncytial Virus (RSV). Enteroviruses, especially CoxB and Echo, are most represented. Unexpectedly, Parainfluenza viruses were detected in seasonal subgroups, with peaks in autumn and spring, and spread homogeneously in different age groups.

Immunogenicity of a new gorilla adenovirus vaccine candidate for COVID-19.

The coronavirus disease 2019 (COVID-19) pandemic caused by the emergent severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) threatens global public health, and there is an urgent need to develop safe and effective vaccines. Here, we report the generation and the preclinical evaluation of a novel replication-defective gorilla adenovirus-vectored vaccine encoding the pre-fusion stabilized Spike (S) protein of SARS-CoV-2. We show that our vaccine candidate, GRAd-COV2, is highly immunogenic both in mice and macaques, eliciting both functional antibodies that neutralize SARS-CoV-2 infection and block Spike protein binding to the ACE2 receptor, and a robust, T helper (Th)1-dominated cellular response. We show here that the pre-fusion stabilized Spike antigen is superior to the wild type in inducing ACE2-interfering, SARS-CoV-2-neutralizing antibodies. To face the unprecedented need for vaccine manufacturing at a massive scale, different GRAd genome deletions were compared to select the vector backbone showing the highest productivity in stirred tank bioreactors. This preliminary dataset identified GRAd-COV2 as a potential COVID-19 vaccine candidate, supporting the translation of the GRAd-COV2 vaccine in a currently ongoing phase I clinical trial (ClinicalTrials.gov: NCT04528641).

Safety of Multiple Vaccinations and Durability of Vaccine-Induced Antibodies in an Italian Military Cohort 5 Years after Immunization.

We previously examined the safety and immunogenicity of multiple vaccines administered to a military cohort, divided into two groups, the first composed of students at military schools, thus operating inside the national borders for at least 3 years, and the other formed of soldiers periodically engaged in a 9-month-long mission abroad (Lebanon). In the current study, we analyzed 112 individuals of this cohort, 50 pertaining to the first group and 62 to the second group, in order to examine the possible late appearance of side effects and to calculate the half-life of the induced antibodies. Moreover, the possible involvement of B-cell polyclonal activation as a pathogenetic mechanism for long term antibody persistence has even been explored. No late side effects, as far as autoimmunity and/or lymphoproliferation appearance, have been noticed. The long duration of the vaccine induced anti-HAV antibodies has been confirmed, whereas the antibodies induced by tetravalent meningococcal polysaccharide vaccine have been found to persist above the threshold for putative protection for a longer time, and anti-tetanus, diphtheria, and polio 1 and 3 for a shorter time than previously estimated. No signs of polyclonal B-cell activation have been found, as a possible mechanism to understand the long antibody persistence.

Human Papillomavirus Infections in Cervical Samples From HIV-Positive Women: Evaluation of the Presence of the Nonavalent HPV Genotypes and Genetic Diversity.

Non-nonavalent vaccine (9v) Human papillomavirus (HPV) types have been shown to have high prevalence among HIV-positive women. Here, 1444 cervical samples were tested for HPV DNA positivity. Co-infections of the 9v HPV types with other HPV types were evaluated. The HPV81 L1 and L2 genes were used to investigate the genetic variability of antigenic epitopes. HPV-positive samples were genotyped using the HPVCLART2 assay. The L1 and L2 protein sequences were analyzed using a self-optimized prediction method to predict their secondary structure. Co-occurrence probabilities of the 9v HPV types were calculated. Non9v types represented 49% of the HPV infections; 31.2% of the non9v HPV types were among the low-grade squamous intraepithelial lesion samples, and 27.3% among the high-grade squamous intraepithelial lesion samples, and several genotypes were low risk. The co-occurrence of 9v HPV types with the other genotypes was not correlated with the filogenetic distance. HPV81 showed an amino-acid substitution within the BC loop (N75Q) and the FGb loop (T315N). In the L2 protein, all of the mutations were located outside antigenic sites. The weak cross-protection of the 9v types suggests the relevance of a sustainable and effective screening program, which should be implemented by HPV DNA testing that does not include only high-risk types.

The Use of Both Therapeutic and Prophylactic Vaccines in the Therapy of Papillomavirus Disease.

Human papillomavirus (HPV) is the most common sexually transmitted virus. The high-risk HPV types (i.e., HPV16, 18, 31, 33, 35, 39, 45, 51, 52, 56, 58, 59) are considered to be the main etiological agents of genital tract cancers, such as cervical, vulvar, vaginal, penile, and anal cancers, and of a subset of head and neck cancers. Three prophylactic HPV vaccines are available that are bivalent (vs. HPV16, 18), tetravalent (vs. HPV6, 11, 16, 18), and non-avalent (vs. HPV6, 11, 16, 18, 31, 33,45, 52, 58). All of these vaccines are based on recombinant DNA technology, and they are prepared from the purified L1 protein that self-assembles to form the HPV type-specific empty shells (i.e., virus-like particles). These vaccines are highly immunogenic and induce specific antibodies. Therapeutic vaccines differ from prophylactic vaccines, as they are designed to generate cell-mediated immunity against transformed cells, rather than neutralizing antibodies. Among the HPV proteins, the E6 and E7 oncoproteins are considered almost ideal as targets for immunotherapy of cervical cancer, as they are essential for the onset and evolution of malignancy and are constitutively expressed in both premalignant and invasive lesions. Several strategies have been investigated for HPV therapeutic vaccines designed to enhance CD4+ and CD8+ T-cell responses, including genetic vaccines (i.e., DNA/ RNA/virus/ bacterial), and protein-based, peptide-based or dendritic-cell-based vaccines. However, no vaccine has yet been licensed for therapeutic use. Several studies have suggested that administration of prophylactic vaccines immediately after surgical treatment of CIN2 cervical lesions can be considered as an adjuvant to prevent reactivation or reinfection, and other studies have described the relevance of prophylactic vaccines in the management of genital warts. This review summarizes the leading features of therapeutic vaccines, which mainly target the early oncoproteins E6 and E7, and prophylactic vaccines, which are based on the L1 capsid protein. Through an analysis of the specific immunogenic properties of these two types of vaccines, we discuss why and how prophylactic vaccines can be effective in the treatment of HPV-related lesions and relapse.

Alpha, Beta, gamma human PapillomaViruses (HPV) detection with a different sets of primers in oropharyngeal swabs, anal and cervical samples.

BACKGROUND: Recent studies have shown a 13-fold increase of oropharyngeal cancer in the presence of HPV, while α-HPV detection seems to be rare in oral cavity in comparison to anal or cervical district, many novel ß and γ types have been isolated in this anatomical site suggesting a wide tropism range. Currently, there are no guidelines recommending HPV oral cavity screening as a mandatory test, and it remains unknown which HPV types should be included in HPV screening programs. Our goal was to assess HPV prevalence in oropharyngeal, anal, and cervical swabs using different sets of primers,which are able to amplify α, ß, γ HPV types. METHODS: We analysed the presence of HPV DNA in oropharyngeal (n = 124), anal (n = 186), cervical specimens (n = 43) from HIV positive and negative patients using FAP59/64 and MY09/11 primers. All untyped strains were genetically characterized through PCR amplification and direct sequencing of partial L1 region, and the resulting sequences were classified through phylogenetic analysis. RESULTS: HPV prevalence was 20.9% in 124 oropharyngeal swab samples, including infections with multiple HPV types (5.6%). HPV prevalence in this anatomical site was significantly associated with serostatus: 63.3%in HIV positive and 36.3% in HIV negative patients (p < 0.05). Unclassified types were detected in 6 specimens. In our analysis, we did not observe any difference in HPV (α, ß, γ) prevalence between men and women. Overall, ß species were the most frequently detected 69.7%. When using anal swabs, for HIV positive patients, ß genus prevalence was 1% and γ genus was 3.7% including 6 unclassified types. In cervical samples from 43 HIV positive women (18 HPV negative and 25 positive by MY09/11 PCR), only one sample was positivite for ß1 species (2.4%) using FAP primers. Six of the untyped strains clustered with sequences from species 7, 9, 10, 8,12 of γ genus. Four sequences remained unclassified. Finally, ß and γ HPV prevalence was significantly lower than their respective HPV prevalence as identified by the Luminex system in all anatomical sites that were analyzed in previous studies. CONCLUSION: This study provides new information about viral isolates present in oropharyngeal site and it will contribute to improve the monitoring of HPV infection.

Oral human Papillomavirus DNA detection in HIV-positive men: prevalence, predictors, and co-occurrence at anal site.

BACKGROUND: HIV-positive patients carry an increased risk of HPV infection and associated cancers. Therefore, prevalence and patterns of HPV infection at different anatomical sites, as well as theoretical protection of nonavalent vaccine should be investigated. Aim was to describe prevalence and predictors of oral HPV detection in HIV-positive men, with attention to nonavalent vaccine-targeted HPV types. Further, co-occurrence of HPV DNA at oral cavity and at anal site was assessed. METHODS: This cross-sectional, clinic-based study included 305 HIV-positive males (85.9% MSM; median age 44.7 years; IQR: 37.4-51.0), consecutively observed within an anal cancer screening program, after written informed consent. Indication for anal screening was given by the HIV physician during routine clinic visit. Paired oral rinse and anal samples were processed for the all HPV genotypes with QIASYMPHONY and a PCR with MY09/MY11 primers for the L1 region. RESULTS: At the oral cavity, HPV DNA was detected in 64 patients (20.9%), and in 28.1% of these cases multiple HPV infections were found. Prevalence of oral HPV was significantly lower than that observed at the anal site (p < 0.001), where HPV DNA was found in 199 cases (85.2%). Oral HPV tended to be more frequent in patients with detectable anal HPV than in those without (p = 0.08). Out of 265 HPV DNA-positive men regardless anatomic site, 59 cases (19.3%) had detectable HPV at both sites, and 51 of these showed completely different HPV types. At least one nonavalent vaccine-targeted HPV type was found in 17/64 (26.6%) of patients with oral and 199/260 (76.5%) with anal infection. At multivariable analysis, factors associated with positive oral HPV were: CD4 cells <200/µL (versus CD4 cells >200/µL, p = 0.005) and >5 sexual partners in the previous 12 months (versus 0-1 partner, p = 0.008). CONCLUSIONS: In this study on Italian HIV-positive men (predominantly MSM), oral HPV DNA was detected in approximately one fifth of tested subjects, but prevalence was significantly lower than that observed at anal site. Low CD4 cell count and increasing number of recent sexual partners significantly increased the odds of positive oral HPV. The absence of co-occurrence at the two anatomical sites may suggest different routes or timing of infection.

An anal cancer screening program for MSM in Italy: Prevalence of multiple HPV types and vaccine-targeted infections.

BACKGROUND: Elevated HPV infection rates have been described in HIV-positive males, placing these subjects at high risk of anal neoplasia. Bivalent, quadrivalent, and nonavalent vaccines to prevent HPV infection have been developed, and recently proposed for gender-neutral immunization programs. OBJECTIVES: In order to estimate the benefit that could be obtained by vaccination of HIV-positive men who have sex with men (MSM), we aimed at describing the frequency of multiple and vaccine-targeted HPV infections in MSM enrolled in an anal cancer screening program. STUDY DESIGN: The anal cancer screening program was conducted between July 2009 and October 2012. Mucosal anal samples were tested for HPV DNA using MY09/MY11 PCR primers and, if positive, genotyped using the CLART2HPV Clinical Array (35HPV types). RESULTS: A total of 220 MSM were screened and 88.6% were positive for HPV DNA: in 86.5% at least one high-risk (HR) type was found and in 13% only low-risk (LR) HPV were found. Multiple infections accounted for 84.5% of HPV DNA-positive cases and overall 160 different HPV genotype combinations were recognized (only three combinations were detected in more than one patient each). Based on strain coverage, at least one vaccine-targeted HPV type was found in 38.9%, 64%, and 78.4% of cases when considering bivalent, quadrivalent and nonavalent vaccines, respectively. At least one HR vaccine-targeted strain was found in 39% of MSM for bivalent and quadrivalent vaccines, and in 64% of cases for nonavalent prevention. CONCLUSIONS: Anal HPV infections in unvaccinated mostly HIV-infected MSM are highly prevalent. The majority of this population has multiple infections with an extremely heterogeneous number of genotype combinations. The nonavalent vaccine could theoretically have prevented a minimum of one HR HPV type in two thirds of subjects.

The clinical significance of HCV core antigen detection during Telaprevir/Peg-Interferon/Ribavirin therapy in patients with HCV 1 genotype infection.

BACKGROUND: Direct-acting antiviral drugs (DAA) regimen improve the SVR rate. However, adverse effects often lead to therapy interruption. This underlines the importance to find some predictive parameters of response in order to consider the possibility of a shorter time of antiviral treatment in the appearance of adverse effects without affecting the success of the therapy. OBJECTIVES: We aimed to examine the HCVAg kinetics in the early phase of treatment and its predictive value of SVR in patients undergoing TPV/Peg-IFN/RBV treatment. STUDY DESIGN: Twenty-three patients infected by HCV genotype 1 (1a n=11; 1b n=12) were included in this prospective study. RESULTS: At baseline the median Log of HCVAg concentration in RVR and EVR patients were 3.15 fmol/L and 3.45 fmol/L, respectively with no significant differences. The baseline median HCV-RNA to HCVAg ratio was 233.77, this ratio was significantly lower when measured on day 1 (27.52) and on day 6 (24.84) (p<0.001). The two-tailed Fisher's exact test indicated that the SVR response is statistically significantly different in patients with detected HCVAg at week1 compared to patients with no detectable HCVAg (p=0.05). The sensitivity, specificity, and negative and positive predictive values (NPV, PPV) were 53.8, 87.5, 53.8 and 87.5%, respectively. The area under the ROC curve was 0.71 at day T6, the best cut-off of 3 fmol/L when evaluated with the HCVAg plasma concentration at day T6. CONCLUSION: Undetectable HCVAg in the early phase of TPV/Peg-IFN/RBV treatment could represent an important parameter for predicting SVR.

Comparison of the Abbott RealTime High Risk HPV with Genomica HPV Clinical Array for the detection of human papillomavirus DNA.

Human papillomavirus (HPV) has been identified as the major cause of cervical cancer worldwide and HPV DNA testing is recommended in primary cervical cancer screening. Several molecular tests for detection/typing of HPV DNA with different sensitivity and specificity are commercially available. The present study compared the performance of the Abbott RealTime High Risk HPV assay and the Genomica HPV Clinical Array CLART2 in 78 specimens (63 cervical smears and 15 rectal/urethral swabs).The typing results of the Genomica assay were in absolute agreement with each of the four possible result categories of the Abbott assay (HPV16, HPV18, Other HR HPV, not detected) in 87.2% (68/78) of the samples, with a Cohen' kappa agreement coefficient for every HR type of 0.62 (95% CI: 0.39-0.85), higher in cervical swabs (k = 0.74, 95% CI: 0.50-0.99) than in rectal/urethral swabs (k = 0.36, 95% CI: 0.00-0.82). There was an excellent agreement of the Genomica results with those of Abbott in cervical samples harbored HPV single infection (100% agreement). Nonetheless, both methods may lose sensitivity for detecting HPV types in multiple infections, giving discordant results (10/78). This underlines the importance of establishing the analytical sensitivity in HPV type detection in single and multiple HPV infections. In rectal/urethral swabs, 5 of 15 (33%) discordant cases were observed, most of which became compatible when the Genomica assay was performed starting from nucleic acid extracted with the Abbott m2000sp system. These results suggest that nucleic extraction based on the magnetic beads technique is suitable for HPV DNA detection in urethral/rectal swabs.

Frequency and multiplicity of human papillomavirus infection in HIV-1 positive women in Italy.

BACKGROUND: Natural history of HPV infection is altered in HIV positive women, with increased risk of cervical dysplasia. Limited data are available about the influence of HPV genotypes and HPV multiple infections on cervical disease in HIV positive women. OBJECTIVES: We determined HPV genotype prevalence in cervical samples from 553 HIV-infected women attending the gynaecological service at "L. Spallanzani" Hospital. Association of HPV multiple infections with cervical abnormalities was investigated. STUDY DESIGN: MY09/MY11 consensus primers were used to detect HPV-DNA; HPV typing was performed by RFLP. A commercial array based kit was used to define unresolved RFLP patterns. RESULTS: HPV was detected in 244/553 (44.1%) patients, correlating with low CD4 counts (p<0.001) and age (p=0.001). Multiple HPV types were observed in 44.4% of cases, more frequently involving HR than LR HPV (OR=12.8, p<0.00001). Multiple HPV infections were associated with low CD4 counts (OR=3.8 in CD4<200 vs CD4≥500 cells/mm(3)). Dyskaryosis was associated with decreased CD4 counts (≥500 vs 200-499 vs <200 cells/mm(3), χ(2) for trend, p=0.001) and with HPV types multiplicity (1 vs 2-3 vs ≥4, χ(2) for trend, p<0.00001). Notably, in 3 H-SIL cases only LR types were detected (HPV62, n=2; HPV81, n=1). CONCLUSIONS: Multiple HPV infections, often involving HR types, are frequent in HIV-infected women. Association between multiple HPV infection, low CD4 count and cytological abnormalities supports the interplay of virological and immunological factors in cervical cancer pathogenesis. Assessment of multiple HPV infections might gain importance in cervical cancer screening, particularly in patients with predisposing factors like immuno-suppression.

Genetic variability in E6, E7 and L1 protein of HPV81 from HIV-1 positive women in Italy.

The genetic variability of E6, E7 and L1 of HPV81 from HIV-1 positive women carrying multiple HPV infections was investigated by clonal analysis for E6 and E7. The range of maximal divergence from the prototype was 0.6%-2.6% for E6 and 1.0%-3.1% for E7. Compared to prototype HPV81, 13 and 10 mutations were identified in E6 and E7, respectively. In the pRB binding domain of E7, all HPV81 clones showed D21, as reported for prototype HPV81 and for HPV16 and 18, while G22 is reported in HPV6 and 11. In the CR3 region, CxxC motif was conserved in all but one clone. The L1 sequence of a single clone from 5 study patients was also established. The range of similarity with prototype HPV81 was 97.8%-99.2%, with 25 polymorphic sites. Two substitutions (R492K and T493S) were observed in 5/5, one (T287N) in 4/5 patients. Among L1 immune-related regions, BC loop presented T56N in 1/5, while FGb loop presented T287N in 4/5 patients. Our data indicate the presence of polymorphisms in all 3 HPV81 genes analyzed, with a certain degree of intra-patient diversity. The importance of polymorphisms on HPV81 persistence and pathogenicity needs to be addressed in longitudinal studies involving larger patient numbers.