Association between MBL2 gene functional polymorphisms and high-risk human papillomavirus infection in Brazilian women

Unusual Localization of AIDS-Related Kaposi's Sarcoma in a Heterosexual Male during the COVID-19 Pandemic: A Case Report

Kaposi's sarcoma is an AIDS-defining illness and remains the most frequent tumor arising in HIV-infected patients with multifactorial etiology. We present a case of a 30-year-old Caucasian male with an 18-year history of HIV infection. The patient was presented with a one-week history of fever, non-productive cough, and skin lesions. There was an associated weakness and weight loss in a duration of 6 months. Clinical examination showed fever, generalized lymphadenopathy, lower limb edema, ascites, and violaceous cutaneous eruption comprising patches, plaques, and nodules. He also had a red nodule on the left conjunctiva, as well as on his oral mucosa. His CD4+ count was below 10/mm3 and ARN-HIV viral load was above 100,000 c/mL, in relation to the antiretroviral failure after five drug regimens. The role of co-infections in oncogenesis and the course of Kaposi's sarcoma were considered in recent studies. Delayed diagnosis of Kaposi's sarcoma in the present case resulted in a negative impact for this patient during the COVID-19 pandemic.

Mannose-binding lectin concentrations in people living with HIV/AIDS infected by HHV-8

Background

Mannose-binding lectin (MBL) plays an important role in the innate immune response by activating the complement system via the lectin pathway, and it has been studied in several viral infections; however, the influence of MBL in PLWHA infected with HHV-8 is unknown. The objective of this study was to verify the association of MBL deficient plasma concentrations in HIV/HHV-8 coinfected and HIV monoinfected patients and to correlate these concentrations with HIV viral load and CD4 counts in both groups.

Results

This was an analytical study of case-controls consisting of PLWHA monitored at the medical outpatient of Infectious and Parasitic Diseases of the clinical hospital in the Federal University of Pernambuco. Plasma concentrations of MBL were obtained by an enzyme-linked immunosorbent assay (ELISA) using a commercial Human Mannose Binding Lectin kit (MyBioSource, Inc.) that was performed according to the manufacturer’s guidelines, with values < 100 ng/ml considered deficient. A total of 245 PLWHA samples were analysed; 118 were HIV/HHV-8 coinfected and 127 were HIV monoinfected; 5.1% (6/118) of the coinfected patients and 3.2% (4/127) of the monoinfected patients (p = 0.445) were considered plasma concentration deficient. The median of the plasma concentrations of MBL in the coinfected patients was 2803 log₁₀ ng/ml and was 2.959 log₁₀ ng/ml in the monoinfected patients (p = 0.001). There was an inverse correlation between the plasma concentrations of MBL and the HIV viral load in both groups, but no correlation with the CD4 count.

Conclusions

Although the plasma concentrations considered deficient in MBL were not associated with HHV-8 infection in PLWHA, the coinfected patients showed lower MBL concentrations and an inverse correlation with HIV viral load, suggesting that there may be consumption and reduction of MBL due to opsonization of HIV and HHV-8, leading to the reduction of plasma MBL and non-accumulation in the circulation.

MBL2 gene polymorphisms in HHV-8 infection in people living with HIV/AIDS

Background

Host genetic factors such as MBL2 gene polymorphisms cause defects in the polymerization of MBL protein and result in a functional deficiency and/or in low serum levels that can influence susceptibility to various viral infections. The aim of this study was to estimate the frequency of alleles, genotypes and haplotypes related to -550, -221 and exon 1 polymorphisms of the MBL2 gene and investigate their association with HHV-8 in people living with HIV/AIDS (PLWHA), as well as the impacts on CD4 cell count and HIV viral load in HIV/HHV-8 coinfected and HIV monoinfected patients.

Results

A cross sectional study in PLWHA, with and without HHV-8 infection, exploring associations between different factors, was performed in the outpatient infectious and parasitic diseases clinic at a referral hospital. Genomic DNA extractions from leukocytes were performed using a commercial Wizard^®Genomic DNA Purification kit (Promega, Madison, WI). The promoter region (-550 and -221) was genotyped with the TaqMan system (Applied TaqMan Biosystems^® genotyping Assays), and the structural region (exon1) was genotyped with Express Sybr Greener Supermix kit (Invitrogen, USA). In total, 124 HIV/HHV-8 coinfected and 213 HIV monoinfected patients were analysed. Median TCD4 counts were significantly lower in HIV/HHV-8 coinfected patients, whereas the mean of the first and last viral load of HIV did not present significant difference. There was no difference in frequency between the LL, YY and AA genotypes between the HIV/HHV-8 coinfected or HIV monoinfected patients. However, in a multivariate analysis, coinfected patients with the intermediate expression haplotype of the MBL2 gene had an odds ratio of 3.1-fold (CI = 1.2–7.6) of their last CD4 cell count being below 350 cells/mm³. Among the coinfected individuals, four developed KS and presented the intermediate expression MBL haplotype, with three being HYA/LXA and one being LYA/LYO.

Conclusions

Host genetic factors, such as -550, -221 and exon 1 polymorphisms, can be related to the may modify coinfections and/or to the development clinical manifestations caused by HHV-8, especially in HIV/HHV-8 coinfected patients who present the intermediate expression haplotypes of MBL.

Mannose-Binding Lectin Does Not Act as a Biomarker for the Progression of Preinvasive Lesions of Invasive Cervical Cancer

OBJECTIVE

To evaluate serum concentrations of mannose-binding lectin (MBL) in women presenting with different human papillomavirus (HPV)-associated cervical lesions.

SUBJECTS AND METHODS

A total of 364 women, who underwent screening for cervical cancer or treatment at the Erasto Gaertner Cancer Hospital (HEG), Curitiba, Brazil, were enrolled in the study. Based on the latest cervical colposcopy-guided biopsy results, the women were divided into 4 groups: cervical intraepithelial neoplasia CIN-I (n = 54), CIN-II (n = 72), CIN-III (n = 145), and invasive cancer (n = 93). A time-resolved immunofluorometric assay was used to measure the MBL concentrations in serum. The statistical analysis was done using GraphPad Prism 6.0. Comparisons were performed by Kruskal-Wallis and Mann-Whitney tests and analyzed by χ2 test; continuous variables are presented as medians and categorical variables as frequencies.

RESULTS

The median MBL concentrations in decreasing order were as follows: invasive cancer: 1,452 ng/mL, CIN-I: 1,324 ng/mL, CIN-II: 1,104 ng/mL, and CIN-III 1,098 ng/mL. However, no statistical significance was found among the 4 groups with HPV-associated lesions (p = 0.11). Equally, the MBL levels did not show a significant association between the age of the patients and the severity of the cervical lesions (p = 0.68). No statistical significance was found in the median values of MBL or in the status of MBL deficient (<100 ng/mL) and high producers (>1,000 ng/mL) among the women in each group (p = 0.77).

CONCLUSION

In this study, there was no statistically significant difference in MBL serum levels among the groups with CIN. Hence MBL serum concentration appeared not to have influenced the progression of HPV-related preinvasive cervical lesions into invasive cancer.

Association of MBL2 exon1 polymorphisms with high-risk human papillomavirus infection and cervical cancers: a meta-analysis

PURPOSE

High-risk human papillomavirus (HR-HPV) infection is the main known cause of cervical cancer. Mannose-binding lectin (MBL) is a recognition molecule that mediates phagocytosis and activates complement.

METHODS

We performed a meta-analysis to investigate the association of MBL-2 functional polymorphisms with HPV infection and cervical cancer (CC).

RESULTS

The meta-analyses indicated an association between the MBL2 exon 1 polymorphisms and susceptibility to HPV infection in the recessive model (OO vs. AA + AO, p = 0.042, 95 % CI 1.02-3.15), and O/O vs. A/A mode (P = 0.023, 95 % CI 1.10-3.40) in Caucasian. Meanwhile, there was a significant association between MBL2 exon 1 polymorphisms and cervical cancer risk in AO vs. AA model (p = 0.035, 95 % CI 1.03-2.26), and Allelic model (O vs. A, p = 0.022, 95 % CI 1.05-1.96) as compared to HR-HPV-infected patients with CC vs. healthy controls in Caucasian. In addition, no an association was observed between MBL2 -550 H/L and -221 X/Y polymorphisms and HPV infection among Caucasians, but we found an association between the MBL2 -550 H/L polymorphism and susceptibility to HR-HPV infection in recessive model (HH vs. LL + LH, p = 0.003, 95 % CI 1.18-2.23), HH vs. LL model (p = 0.021, 95 % CI 1.07-2.19), and allelic model(H vs. L, p = 0.042, 95 % CI 1.01-1.40) in Asians.

CONCLUSIONS

Collectively, we suggest that the MBL2 gene exon1 polymorphisms are associated with increased risk of high-risk HPV infection and cervical cancer development among Caucasians. Additionally, no significant association was found between the MBL2 -550 H/L or -221 X/Y polymorphisms and HPV infection in Caucasians, but there may be potential links in Asians.

MBL2 polymorphisms in women with atypical squamous cells of undetermined significance

Infection with high risk Human papillomavirus (HPV) is the main known cause of cervical cancer. HPV induces different grades of lesions: among them, Atypical squamous cells of undetermined significance are abnormal lesions that could evolve in pre-cancer lesions or spontaneously regress. The mannose binding lectin (MBL) is an innate immunity serum protein also found in cervico-vaginal mucosa, whose expression is known to be affected by polymorphisms in exon 1 and promoter of the MBL2 gene. In the present study the possible association between MBL2 functional polymorphisms and susceptibility to develop atypical squamous cells of undetermined significance was investigated in a group of women from North-East of Italy, stratified for HPV infection status. The MBL2 D and O alleles and the deficient producer combined genotypes, responsible for low MBL production, were more represented among atypical squamous cells of undetermined significance positive women than healthy controls and the results were confirmed when only HPV negative samples were considered. These results suggest a possible involvement of MBL2 functional polymorphisms in atypical squamous cells of undetermined significance susceptibility.

The relationship between serum mannose-binding lectin levels and acute ischemic stroke risk

Complement activation and inflammation have been suggested in the pathogenesis of stroke, mannose-binding lectin (MBL) were found to have roles during the process. The aim of this study was to investigate the relationship between acute ischemic stroke (AIS) and serum MBL levels in Chinese population. From January 1 to June 30 2013, all patients with first-ever AIS were recruited to participate in the study. Serum MBL levels and routine test were examined. The National Institutes of Health Stroke Scale (NIHSS) score was assessed on admission blinded to MBL levels. During the inclusion period, 148 patients with AIS were registered and completed study. The results indicated that the serum MBL levels were significantly (p < 0.0001) higher in acutely ischemic stroke patients as compared to normal controls [1,332; interquartile range (IQR) 996-2,134 μg/L and 897; IQR 678-1,100 μg/L, respectively]. There was a correlation between serum levels of MBL and NIHSS score [r (spearman) = 0.608, p < 0.0001). In multivariate analysis, serum MBL as a continuous variable was associated with an increased risk of AIS, after adjustment for above possible confounders (OR 1.002, 95 % CI 1.001-1.008; p < 0.0001). These results indicated that elevated MBL levels could be considered as an independent stroke risk factor in Chinese population, suggesting a role of MBL and the lectin pathway of complement activation in the pathogenesis of stroke.

Mannose-binding lectin 2 gene and risk of adult glioma

BACKGROUND AND AIMS

The immune system is likely to play a key role in the etiology of gliomas. Genetic polymorphisms in the mannose-binding lectin gene, a key activator in the lectin complement pathway, have been associated with risk of several cancers.

METHODS

To examine the role of the lectin complement pathway, we combined data from prospectively collected cohorts with available DNA specimens. Using a nested case-control design, we genotyped 85 single nucleotide polymorphisms (SNPs) in 9 genes in the lectin complement pathway and 3 additional SNPs in MBL2 were tested post hoc). Initial SNPs were selected using tagging SNPs for haplotypes; the second group of SNPs for MBL2 was selected based on functional SNPs related to phenotype. Associations were examined using logistic regression analysis. All statistical tests were two-sided. Nominal p-values are presented and are not corrected for multiple comparisons.

RESULTS

A total of 143 glioma cases and 419 controls were available for this analysis. Statistically significant associations were observed for two SNPs in the mannose-binding lectin 2 (ML2) gene and risk of glioma (rs1982266 and rs1800450, test for trend p = 0.003 and p = 0.04, respectively, using the additive model). One of these SNPs, rs1800450, was associated with a 58% increase in glioma risk among those carrying one or two mutated alleles (odds ratio = 1.58, 95% confidence interval = 0.99-2.54), compared to those homozygous for the wild type allele.

CONCLUSIONS

Overall, our findings suggest that MBL may play a role in the etiology of glioma. Future studies are needed to confirm these findings which may be due to chance, and if reproduced, to determine mechanisms that link glioma pathogenesis with the MBL complement pathway.

Mannan-binding lectin in malignancy

Complement may play a dual role in cancer: it may contribute either to the development or to the inhibition of tumour growth. Its components may be candidate biomarkers facilitating the disease detection, its progress or effectiveness of therapy. Additionally, complement deficiencies may increase the risk of infections and contribute to the higher mortality, especially in patients undergoing aggressive chemotherapy. In this paper, possible cancer associations of one of the factors activating complement via the lectin pathway, mannan-binding lectin (MBL), are discussed.

MBL serum concentration in women with HPV presenting CIN III lesions

PURPOSE

This study proposes to assess MBL serum concentrations in HPV positive women that developed high risk preinvasive lesions, CIN III.

MATERIALS AND METHODS

A total of 90 consecutive women (mean age 32.2 years, range 18-45 years) with CIN III lesions confirmed by cone biopsy were enrolled as cases at the gynecology cancer department of the Erasto Gaertner Hospital, a center of reference for cancer treatment in Southern Brazil. All the patients were HPV positive. In addition, 81 healthy women, voluntary blood donors, were enrolled as healthy control subjects (mean age 33.3 years, range 14-71 years) with no evidence of HPV infection, tested by hybrid capture, or CIN lesions, from the same geographic area.

RESULTS

The median concentration of MBL in the cases was 912 ng/ml (IQR: 100-5820 ng/ml) and in the controls was 1207.3 ng/ml (IQR 100-4320.6 ng/ml). No statistically significant difference was observed between cases and controls.

CONCLUSION

This study reports data on MBL serum concentrations in HPV infected women for the first time. The analysis of our findings did not show a statistically significant difference between MBL serum concentrations in HPV women that developed CIN III lesions and healthy controls.

Polymorphisms of innate immunity receptors in infection by parasites

The innate immune system is the first line of defence against infection by pathogenic bacteria, virus and parasites and is also responsible for initiating an adaptive immune response. In contrast to the receptors of adaptive immunity (TCRs and antibodies) which are generated by gene recombination, receptors of the innate immune system are encoded in the germline and are thus inherited from generation to generation. Although evolutionarily selected, the genes encoding the innate recognition receptors show variations among individuals, and these polymorphisms may have an impact on the ability of an individual to deal with an infection. In recent years, several polymorphisms have been identified in innate recognition receptors, and efforts are being made to determine whether these polymorphisms are associated with a higher or lower susceptibility to infectious diseases. These studies will allow a better understanding of the role of innate receptors in specific diseases and are valuable in the design of preventive or therapeutic interventions to fight the disease. In this review, we summarize studies aimed at determining the influence of polymorphisms in innate recognition receptors on the susceptibility to diseases caused by parasites.

A clinical case-control study on the association between mannose-binding lectin and susceptibility to HIV-1 infection among northern Han Chinese population

Mannose-binding lectin (MBL) is a key molecule of the innate immune system and a competent to bind carbohydrates of a variety of microorganisms, resulting in complement activation and opsonophagocytosis against various pathogens. However, there is no systemic investigation on the MBL's role in innate immune responses against HIV-1 infection among northern Han Chinese. This study investigated the association between MBL and HIV-1 infection susceptibility among northern Han Chinese. A total of 91 HIV-1 infected patients and 91 HIV-1 seronegative healthy individuals were recruited. Six polymorphisms of MBL2 gene were genotyped by pyrosequencing. The quantitative measurement of serum MBL concentration and MBL complex activity were performed by ELISA. The CD4+ T-cell counts were determined by flow cytometry. The plasma viral loads of 91 HIV-1 infected patients were determined by bDNA method. The results show that there is an association between MBL and HIV-1 infection susceptibility among northern Han Chinese. The individuals with B variant, low serum MBL concentration and low MBL complex activity are more susceptible to HIV-1 infection.

MBL expression in patients with recurrent tonsillitis

OBJECTIVE

We evaluated mannose binding lectin (MBL) protein production and histological localization, MBL2 gene expression and genotypes distribution in patients characterized by recurrent tonsillitis, with the aim of verifying the innate immune response to the infection and inflammation occurring in the tonsils.

METHODS

MBL2 exon 1 and promoter polymorphims were detected by PCR amplification and subsequent direct sequencing of the amplicons. Monoclonal antibodies to MBL were used on frozen sections of tonsils for the immunohistochemical localization of MBL protein. MBL Oligomer ELISA kit was used to quantify the level of MBL in the serum of the 30 patients with recurrent tonsillitis. Quantitative RT PCR for the evaluation of MBL2 expression of MBL high producers (HP), low producers (LP) and deficient producers (DP) was performed using the Hs00175093 gene-expression Assay on Demand.

RESULTS

The distribution of the MBL2 combined genotypes was as follows: 21 HP (70%; 15 HYA/HYA, 6 HYA/LXA), 6 LP (20%; 5 HYA/0, 1 LXA/LXA) and 3 DP (10%, all 0/0). MBL levels were directly correlated to the MBL2 combined genotypes: HP patients showed higher mean MBL concentration of 4044 ng/mL, LP patients were characterized by a mean of 905 ng/mL whereas those with DP combined genotype presented extremely low levels of MBL (mean value of 74 ng/mL) (p=0.0005). Immunohistochemistry performed on tonsils sections demonstrated that MBL was widely distributed throughout the surface of the basal lamina of all the 21 HP subjects. MBL was undetectable in situ in both LP and DP patients. MBL2 expression, although at very low levels, was found for the HP group, the LP and the DP group as well.

CONCLUSIONS

We confirmed the genotype-phenotype correlation of MBL2 gene exon 1 and promoter polymorphisms with the quantitative production of serum MBL, we reported a very low MBL2 expression at local level in tonsils and we determined the in situ localization of MBL in the basal lamina of the tonsils of patients who underwent to tonsillectomy. Our findings suggest an important role of MBL protein in the innate immune response of the tonsil to pathogens, as in recurrent infection and inflammation.