The association between non-viral sexually transmitted infections and pregnancy outcome in Latin America and the Caribbean: A systematic review

Introduction

Non-viral sexually transmitted infections are known to be associated with adverse pregnancy outcomes. For these pathogens, standard antenatal screening is not broadly performed in Latin America and the Caribbean. The aim of this study was to comprehensively review the association of non-viral sexually transmitted infections and neonatal outcomes among pregnant women in the region.

Methods

Four databases (PubMed, Embase, SciELO and LILACS) were examined to identify eligible studies published up to September 2022. English or Spanish cross-sectional, case-control and cohort studies assessing the association of non-viral sexually transmitted infections and adverse pregnancy outcomes were evaluated. Articles were firstly screened by means of title and abstract. Potential articles were fully read and assessed for inclusion according to the eligibility criteria. Snowballing search was performed by screening of bibliographies of the chosen potentially relevant papers. Risk of bias within studies was assessed using the Joanna Briggs Institute reviewer's manual.

Results

A selection of 10 out of 9772 search records from five Latin America and the Caribbean countries were included. Six studies associated Treponema pallidum infection with preterm birth (1/6), history of previous spontaneous abortion (2/6), fetal and infant death (1/6), low birth weight (1/6) and funisitis of the umbilical cord (1/6). Three studies associated Chlamydia trachomatis infection with preterm birth (2/3), ectopic pregnancy (1/3) and respiratory symptoms on the newborn (1/3). One study associated Mycoplasma genitalium infection with preterm birth.

Conclusion

This review provides evidence on the association of non-viral sexually transmitted infections with adverse pregnancy outcomes. Further investigation is needed to establish more associations between non-viral sexually transmitted infections and pregnancy outcome, especially for Mycoplasma genitalium, Trichomonas vaginalis and Neisseria gonorrhoeae. Overall, this review calls for more research for public health interventions to promote screening of non-viral sexually transmitted infections during pregnancy, among high-risk population groups of pregnant women living in the region.

Comparison between the Roche Cobas 4800 Human Papillomavirus (HPV), Abbott RealTime High-Risk HPV, Seegene Anyplex II HPV28, and Novel Seegene Allplex HPV28 Assays for High-Risk HPV Detection and Genotyping in Mocked Self-Samples

Infection with high-risk human papillomavirus (hrHPV) is well recognized as the main cause of cervical cancer. The recently developed Seegene Allplex HPV28 assay is a novel quantitative PCR (qPCR) assay designed to separately detect and quantify 28 distinct HPV genotypes in a fully automated and user-friendly manner. This study evaluated and compared the performance of this new assay with the performance of the Roche Cobas 4800, the Abbott RealTime high-risk HPV, and the Seegene Anyplex II HPV28 assays. A total of 114 mocked self-samples, i.e., semicervical samples collected by gynecologists using the Viba-Brush, were analyzed with all four HPV assays. Agreement in terms of detecting and genotyping HPV was assessed by the mean of the Cohen's kappa (κ) coefficient. Results of all four HPV assays agreed in 85.9% of the cases when using the Abbott RealTime manufacturer's recommended quantification cycle (Cq) cutoff for positivity (<32.00) and 91.2% when using an adapted range (32.00 to 36.00). An intercomparison of the included assays demonstrated an overall agreement ranging from 85.9 to 100.0% (κ = 0.42 to 1.00) when using the manufacturer's guidelines and 92.9 to 100.0% (κ = 0.60 to 1.00) with the adapted range. For all assays, highly significant, strongly positive Pearson correlations were shown between the Cq values of positive test results. This study thereby shows high concordance between results of the included HPV assays on mocked self-samples. Based on these findings, we imply that the novel Allplex HPV28 assay demonstrates a comparable performance to those of available qPCR HPV assays, potentially providing opportunities for the simplification and standardization of future large-scale testing. IMPORTANCE This study proves that the novel Allplex HPV28 assay has a good diagnostic performance in comparison with the well-known, validated, and frequently used Roche Cobas 4800, Abbott RealTime, and Anyplex II HPV28 assays. According to our experience, the novel Allplex HPV28 assay had a user-friendly and automated workflow with short hands-on time, had an open platform which facilitates the use of add-on assays, and provided quick and easy-to-interpret results. Together with its ability to detect and quantify 28 HPV genotypes, the Allplex HPV28 assay could therefore potentially provide opportunities for the simplification and standardization of future diagnostic testing programs.

The association between adverse pregnancy outcomes and non-viral genital pathogens among women living in sub-Saharan Africa: a systematic review

Adverse pregnancy outcomes are the main causes of maternal and neonatal morbidity and mortality, including long-term physical and psychological sequelae. These events are common in low- and middle-income countries, particularly in Sub Saharan Africa, despite national efforts. Maternal infections can cause complications at any stage of pregnancy and contribute to adverse outcomes. Among infections, those of the genital tract are a major public health concern worldwide, due to limited availability of prevention, diagnosis and treatment approaches. This applies even to treatable infections and holds true especially in Sub-Saharan Africa. As late as 2017, the region accounted for 40% of all reported treatable non-viral genital pathogens worldwide, many of which have been independently associated with various adverse pregnancy outcomes, and that include Chlamydia trachomatis, Neisseria gonorrhoeae, Trichomonas vaginalis, Treponema pallidum. Two databases (PubMed and Embase) were examined to identify eligible studies published up to October 2022. This study reviewed findings on the association between infections by treatable non-viral genital pathogens during pregnancy and adverse pregnancy outcomes among women living in Sub-Saharan Africa. Articles' title and abstract were screened at first using keywords as "sexually transmitted infections", "non-viral", "adverse pregnancy outcome", "Africa", "sub-Saharan Africa", "pregnant women", "pregnancy", and "pregnancy outcome". Subsequently, according to the eligibility criteria, potential articles were read in full. Results showed that higher risk of preterm birth is associated with Treponema pallidum, Chlamydia trachomatis and Candida albicans infections. Additionally, rates of stillbirth, neonatal death, low birth weight and intrauterine growth restriction are also associated with Treponema pallidum infection. A better insight on the burden of non-viral genital pathogens and their effect on pregnancy is needed to inform antenatal care guidelines and screening programs, to guide the development of innovative diagnostic tools and other strategies to minimize transmission, and to prevent short- and long-term complications for mothers and children.

The impact of health education interventions on HPV vaccination uptake, awareness, and acceptance among people under 30 years old in India: a literature review with systematic search

Background

The HPV vaccine is used as one of the main prevention tools for HPV-related cancers globally, yet it is not part of the Indian National Immunization program. In light of the introduction of the indigenous vaccine, we examine the effectiveness of health education about uptake, acceptance, and awareness.

Methods

Research was performed in the following databases: PubMed, CINAHL, Scopus, and Embase to identify studies between 2008 and 2022. Studies were included if: they were conducted in India including primary data research and health education intervention, and participants were between 9 and 29 years old.

Results

Out of the 10.952 results, 7 studies were included. Four studies focused on adolescent girls, aged from 9 to 20 years old, and 3 on university students aged from 17 to 26 years. Five studies were implemented in urban areas and 2 in rural areas. Health education interventions proved to be effective in increasing uptake, awareness, and acceptance of the HPV vaccine. The barriers included among others: cost, lack of awareness, and cultural barriers.

Conclusion

Observations from this study outline immediate action for policymakers to educate and encourage the young population toward HPV vaccination. Future programs should be aimed at different population groups and be adjusted according to their special characteristics and needs. Attention should be given to the male population and marginalized groups. The involvement of various stakeholders proved to be beneficial, and it is highly recommended.

Antibiotic Use in Pregnancy: A Global Survey on Antibiotic Prescription Practices in Antenatal Care

Antibiotic prescription and use practices in the antenatal care setting varies across countries and populations and has the potential to significantly contribute to the global spread of antibiotic resistance. This study aims to explore how healthcare practitioners make decisions about antibiotic prescriptions for pregnant women and what factors play a role in this process. A cross-sectional exploratory survey consisting of 23 questions, including 4 free-text and 19 multiple-choice questions, was distributed online. Quantitative data were collected through multiple-choice questions and was used to identify the most common infections diagnosed and the type of antibiotics prescribed. Qualitative data were gathered through free-text answers to identify gaps, challenges, and suggestions, and the data were analyzed using thematic analysis. A total of 137 complete surveys mostly from gynecologists/obstetricians from 22 different countries were included in the analysis. Overall, national and international clinical guidelines and hospital guidelines/protocols were the most frequently used sources of information. This study highlights the crucial role of laboratory results and guidelines at different levels and emphasizes region-specific challenges and recommendations. These findings underscore the pressing need for tailored interventions to support antibiotic prescribers in their decision-making practice and to address emerging resistance.

Effect of COVID-19 on antenatal care: experiences of medical professionals in the Netherlands

BACKGROUND

COVID-19 has greatly affected the delivery of all health care services globally. Antenatal care is one area of care that has been impacted, despite the fact that attending antenatal check-ups is essential for pregnant women and cannot be postponed. Little is known about how exactly ANC provision has changed in the Netherlands, or how the changes have impacted midwives and gynaecologists providing those services.

METHODS

This study used a qualitative research design to investigate changes in individual and national practice following the onset of the COVID-19 pandemic. The study involved a document analysis of protocols and guidelines for ANC provision to evaluate how those changed following the onset of the COVID-19 pandemic and semi-structured interviews with ANC care providers (i.e., gynaecologists and midwives).

RESULTS

Guidance was issued by multiple organizations, during the pandemic, on how to approach the risk of infection in pregnant women, recommending several changes to ANC to protect both pregnant women and ANC providers. Both midwives and gynaecologists reported changes in their practice. With less face-to-face consultations happening, digital technologies became critical in the care of pregnant women. Shorter and fewer visits were reported, with midwifery practices adjusting their guidelines further than hospitals. Challenges, with high workloads and lack of personal protective equipment were discussed.

CONCLUSIONS

The COVID-19 pandemic has had an immense impact on the health care system. This impact has had both negative and positive effects on the provision of ANC in the Netherlands. It is important to learn from the current COVID-19 pandemic and adapt ANC, as well as health care systems as a whole, to be better prepared for future health crises and ensure continuous provision of good quality care.

Frequency of Chlamydia trachomatis and Neisseria gonorrhoeae in Patients with Imminent Preterm Delivery on the Island of Curaçao

Sexually transmitted infections are one of the important risk factors for preterm delivery, which is among the important contributors to perinatal morbidity and mortality. The aim of this study was to assess the prevalence of Chlamydia trachomatis and Neisseria gonorrhoeae infections in women with imminent preterm delivery in Curaçao, an island of the Dutch Caribbean. All women from Curaçao with either preterm premature rupture of the membranes or preterm labor, common indications of imminent preterm delivery, and presenting at the Curaçao Medical Center between 15 November 2019 and 31 December 2020, were included in this single cohort study. Data were retrospectively collected from medical records. The presence of Chlamydia trachomatis and Neisseria gonorrhoeae was assessed by Cepheid GeneXpert ^® (Xpert) CT/NG assay (Sunnyvale, CA, USA). In the included cohort, the prevalence of Chlamydia trachomatis infection was 15.5% and of Neisseria gonorrhoeae infection was 2.1%. All patients infected with Neisseria gonorrhoeae were co-infected with Chlamydia trachomatis. The prevalence of Chlamydia trachomatis and Neisseria gonorrhoeae infections in patients with imminent preterm delivery in Curaçao is high. It is recommended to test all patients with imminent preterm delivery for these sexually transmitted infections and possibly consider testing all women in early pregnancy on the island.

Exploring solutions to improve antenatal care in resource-limited settings: an expert consultation

Background

Shortage or low-quality antenatal care is a complex and “wicked” problem relying heavily on contextual, socio-cultural, environmental and intersectional aspects. We report the outcome of an expert consultation discussing solutions to improve antenatal care quality, access and delivery in low- and middle-income countries, and providing recommendations for implementation.

Methods

The social ecological model was used as an analytical lens to map and interpret discussion points and proposed solutions. In addition, a conceptual framework for maternal and neonatal health innovation based on the building blocks of the World Health Organization health system and the Tanahashi Health Systems Performance Model provided a logical overview of discussed solutions.

Results

Many barriers and norms continue to hinder antenatal care access. From values, beliefs, traditions, customs and norms, to poor resource allocation, there is a need of reshaping health systems in order to provide high quality, respectful maternal and childcare. The burden of poor maternal health, morbidity and mortality is concentrated among populations who are vulnerable due to gender and other types of discrimination, have financial constraints and are affected by humanitarian crises.

Conclusions

In order to address maternal health issues, good quality and evidence-based services should be guaranteed. Investments in strengthening health systems, including data and surveillance systems and skilled health workforce, should be considered an essential step towards improving maternal health services.

The Vaginal Microbiota Composition and Genital Infections during and after Pregnancy among Women in Pemba Island, Tanzania

We investigated the vaginal microbiota (VMB) composition, prevalence of genital pathogens and their association among pregnant and post-delivery women in Pemba Island, Tanzania. Vaginal swabs were collected from 90 women, at two time points during pregnancy (<20 weeks of gestational age [GA] and ≥20 weeks GA) and once after delivery, when possible. IS-pro assay was used for VMB characterization. Chlamydia trachomatis (CT), Neisseria gonorrhea (NG), Trichomonas vaginalis (TV), Mycoplasma genitalium (MG) and human papillomavirus (HPV) were detected by qPCRs. VMB were mostly Lactobacillus dominant during pregnancy and non-Lactobacillus dominant post-delivery. A significant decrease in VMB richness was observed during pregnancy among paired and unpaired samples. Shannon diversity was significantly lower during pregnancy than post-delivery among unpaired samples. Klebsiella species and Streptococcus anginosus were the most commonly identified pathobionts at all timepoints. A high abundance of pathobionts was mostly seen in women with non-Lactobacillus dominant VMB. At ≥20 weeks GA timepoint during pregnancy, 63.0% of the women carrying one or more genital pathogen (either HPV, CT, TV, or MG) had L. iners dominant VMB. NG was not detected pre-delivery. This study contributes evidence on VMB composition, its changes during pregnancy and post-delivery, and their association with pathobionts and genital pathogens.

Composition of the vaginal microbiota during pregnancy in women living in sub-Saharan Africa: a PRISMA-compliant review

BACKGROUND

The vaginal microbiota (VMB) are the set of microorganisms residing in the human vagina. During pregnancy, their composition is Lactobacillus-dominant in most Caucasian women. Previous studies suggest that the VMB of women with African ancestry is more likely to be non-Lactobacillus dominant (dysbiotic) compared to other populations, and possibly relate to the high incidence of pregnancy complications, such as preterm birth. This work reviewed the literature on VMB composition in pregnant women from sub-Saharan Africa.

METHODS

A search was conducted in PubMed and Embase databases following PRISMA guidelines. Observational and intervention studies analysing VMB communities from sub-Saharan African pregnant women using molecular techniques were included.

RESULTS

Ten studies performed in seven sub-Saharan African countries were identified. They independently showed that Lactobacillus-dominant VMB (particularly L. iners or L. crispatus) or VMB containing Lactobacilli are the most prevalent, followed by a more diverse anaerobe-dominant VMB, in the studied populations. The majority of pregnant women with a sexually-transmitted infection had a Lactobacillus-dominant VMB, but with a significantly higher presence of anaerobic species.

CONCLUSION

In agreement with studies performed in other populations, Lactobacillus species are the most prevalent VMB species during pregnancy in sub-Saharan African women. The frequency of diverse anaerobe-dominant VMB is high in these populations. In Africa, studies on VMB in pregnancy are scant, heterogeneous in methodology, and knowledge remains limited. More insights on VMB composition and their possible sequalae among these populations is needed.

The impact of antenatal syphilis point of care testing on pregnancy outcomes: A systematic review

Background

Mother-to-child transmission of syphilis remains a leading cause of neonatal death and stillbirth, disproportionally affecting women in low-resource settings where syphilis prevalence rates are high and testing rates low. Recently developed syphilis point-of-care tests (POCTs) are promising alternatives to conventional laboratory screening in low-resource settings as they do not require a laboratory setting, intensive technical training and yield results in 10–15 minutes thereby enabling both diagnosis and treatment in a single visit. Aim of this review was to provide clarity on the benefits of different POCTs and assess whether the implementation of syphilis POCTs is associated with decreased numbers of syphilis-related adverse pregnancy outcomes.

Methods

Following the PRISMA guidelines, three electronic databases (PubMed, Medline (Ovid), Cochrane) were systematically searched for intervention studies and cost-effectiveness analyses investigating the association between antenatal syphilis POCT and pregnancy outcomes such as congenital syphilis, low birth weight, prematurity, miscarriage, stillbirth as well as perinatal, fetal or infant death.

Results

Nine out of 278 initially identified articles were included, consisting of two clinical studies and seven modelling studies. Studies compared the effect on pregnancy outcomes of treponemal POCT, non-treponemal POCT and dual POCT to laboratory screening and no screening program. Based on the clinical studies, significantly higher testing and treatment rates, as well as a significant reduction (93%) in adverse pregnancy outcomes was reported for treponemal POCT compared to laboratory screening. Compared to no screening and laboratory screening, modelling studies assumed higher treatment rates for POCT and predicted the most prevented adverse pregnancy outcomes for treponemal POCT, followed by a dual treponemal and non-treponemal POCT strategy.

Conclusion

Implementation of treponemal POCT in low-resource settings increases syphilis testing and treatment rates and prevents the most syphilis-related adverse pregnancy outcomes compared to no screening, laboratory screening, non-treponemal POCT and dual POCT. Regarding the benefits of dual POCT, more research is needed. Overall, this review provides evidence on the contribution of treponemal POCT to healthier pregnancies and contributes greater clarity on the impact of diverse diagnostic methods available for the detection of syphilis.

The Association Between Vaginal Microbiota Dysbiosis, Bacterial Vaginosis, and Aerobic Vaginitis, and Adverse Pregnancy Outcomes of Women Living in Sub-Saharan Africa: A Systematic Review

Background: Previous studies have described the association between dysbiosis of the vaginal microbiota (VMB) and related dysbiotic conditions, such as bacterial vaginosis (BV) and aerobic vaginitis (AV), and various adverse pregnancy outcomes. There is limited overview of this association from countries in sub-Saharan Africa (SSA), which bear a disproportionally high burden of both vaginal dysbiotic conditions and adverse pregnancy outcomes. This systematic review assesses the evidence on the association between VMB dysbiosis, BV, and AV, and late adverse pregnancy outcomes in women living in SSA.

Methods: The Preferred Reporting Items for Systematic Review and Meta-Analysis Statement (PRISMA) guidelines were followed. Three databases [PubMed, Embase (Ovid), and Cochrane] were used to retrieve observational and intervention studies conducted in SSA that associated VMB dysbiosis, BV, or AV and preterm birth/labor/delivery, preterm rupture of membranes (PROM), low birthweight, small for gestational age, intrauterine growth restriction, intrauterine infection, intrauterine (fetal) death, stillbirth, perinatal death, or perinatal mortality.

Results: Twelve studies out of 693 search records from five SSA countries were included. One study identified a positive association between VMB dysbiosis and low birthweight. Despite considerable differences in study design and outcome reporting, studies reported an association between BV and preterm birth (7/9), low birthweight (2/6), PROM (2/4), intrauterine infections (1/1), and small for gestational age (1/1). None of the retrieved studies found an association between BV and pregnancy loss (5/5) or intrauterine growth retardation (1/1). At least two studies support the association between BV and PROM, low birthweight, and preterm birth in Nigerian pregnant women. No reports were identified investigating the association between AV and late adverse pregnancy outcomes in SSA.

Conclusion: Two of the included studies from SSA support the association between BV and PROM. The remaining studies show discrepancies in supporting an association between BV and preterm birth or low birthweight. None of the studies found an association between BV and pregnancy loss. As for the role of VMB dysbiosis, BV, and AV during pregnancy among SSA women, additional research is needed. These results provide useful evidence for prevention efforts to decrease vaginal dysbiosis and its contribution to adverse pregnancy outcomes in SSA.

Detection of high-risk human papillomavirus (HPV) by the novel AmpFire isothermal HPV assay among pregnant women in Pemba Island, Tanzania

Introduction

human papillomavirus (HPV) is the most common sexually transmitted virus in the world. Prevalence of infection differs, with highest rates reported in sub-Saharan African, including the country of Tanzania. In pregnancy, the hormonal changes and immune changes seem to facilitate HPV persistence, increasing the cancer risk and the risk of vertical transmission towards the placenta and the fetus. The burden of HPV infection is still high despite multiple screening and detection test available. The AmpFire® HPV assay is a novel nucleic acid isothermal amplification with real-time fluorescence detection assay that can test simultaneously 15 high-risk HPV. This nested cohort study aims to contribute evidence on the prevalence of HPV infection and persistence across two time points among pregnant women in Pemba island, Tanzania.

Methods

vaginal swabs that were previously collected during pregnancy were stored in eNAT buffer (n₁=385 and n₂=187) and were tested with AmpFire® screening assay, for simultaneous detection of the HPV 16, 18 and other high-risk HPV genotypes 31, 33, 35, 39, 45, 51, 52, 53, 56, 58, 59, 66 and 68.

Results

the AmpFire® HPV assay detected an 11% and 6% high-risk HPV prevalence at the two time points among pregnant women in Pemba island, consecutively. For the 133 women whose samples were tested at both time points, the persistence rate of high-risk HPV was 64%.

Conclusion

novel isothermal HPV assay, such as the AmpFire®, might be feasible to use in low-income regions.

The Interplay Between Reproductive Tract Microbiota and Immunological System in Human Reproduction

In the last decade, the microbiota, i.e., combined populations of microorganisms living inside and on the surface of the human body, has increasingly attracted attention of researchers in the medical field. Indeed, since the completion of the Human Microbiome Project, insight and interest in the role of microbiota in health and disease, also through study of its combined genomes, the microbiome, has been steadily expanding. One less explored field of microbiome research has been the female reproductive tract. Research mainly from the past decade suggests that microbial communities residing in the reproductive tract represent a large proportion of the female microbial network and appear to be involved in reproductive failure and pregnancy complications. Microbiome research is facing technological and methodological challenges, as detection techniques and analysis methods are far from being standardized. A further hurdle is understanding the complex host-microbiota interaction and the confounding effect of a multitude of constitutional and environmental factors. A key regulator of this interaction is the maternal immune system that, during the peri-conceptional stage and even more so during pregnancy, undergoes considerable modulation. This review aims to summarize the current literature on reproductive tract microbiota describing the composition of microbiota in different anatomical locations (vagina, cervix, endometrium, and placenta). We also discuss putative mechanisms of interaction between such microbial communities and various aspects of the immune system, with a focus on the characteristic immunological changes during normal pregnancy. Furthermore, we discuss how abnormal microbiota composition, “dysbiosis,” is linked to a spectrum of clinical disorders related to the female reproductive system and how the maternal immune system is involved. Finally, based on the data presented in this review, the future perspectives in diagnostic approaches, research directions and therapeutic opportunities are explored.

Sexually Transmitted Infections and Behavioral Determinants of Sexual and Reproductive Health in the Allahabad District (India) Based on Data from the ChlamIndia Study

BACKGROUND

Sexually transmitted infections (STIs), like Chlamydia trachomatis and Neisseria gonorrhoeae (CT and NG, respectively) are linked to an important sexual and reproductive health (SRH) burden worldwide. Behavior is an important predictor for SRH, as it dictates the risk for STIs. Assessing the behavior of a population helps to assess its risk profile.

METHODS

Study participants were recruited at a gynecology outpatient department (OPD) in the Allahabad district in Uttar Pradesh India, and a questionnaire was used to assess demographics, SRH, and obstetric history. Patients provided three samples (urine, vaginal swab, and whole blood). These samples were used to identify CT and NG using PCR/NAAT and CT IgG ELISA.

RESULTS

A total of 296 women were included for testing; mean age was 29 years. No positive cases of CT and NG were observed using PCR/NAAT. A 7% (22/296) positivity rate for CT was observed using IgG ELISA. No positive association was found between serology and symptoms (vaginal discharge, abdominal pain, dysuria, and dyspareunia) or adverse pregnancy outcomes (miscarriage and stillbirth). Positive relations with CT could be observed with consumption of alcohol, illiteracy, and tenesmus (p-value 0.02-0.03).

DISCUSSION

STI prevalence in this study was low, but a high burden of SRH morbidity was observed, with a high symptomatic load. High rates of miscarriage (31%) and stillbirth (8%) were also observed among study subjects. No associations could be found between these ailments and CT infection. These rates are high even for low- and middle-income country standards.

CONCLUSION

This study puts forward high rates of SRH morbidity, and instances of adverse reproductive health outcomes are highlighted in this study, although no associations with CT infection could be found. This warrants more investigation into the causes leading to these complaints in the Indian scenario and potential biases to NAAT testing, such as consumption of over-the-counter antimicrobials.

The Potential Role for Host Genetic Profiling in Screening for Chlamydia-Associated Tubal Factor Infertility (TFI)-New Perspectives

Host immunogenetic factors can affect late complications of urogenital infections with Chlamydia trachomatis. These findings are creating new avenues for updating existing risk prediction models for C. trachomatis-associated tubal factor infertility (TFI). Research into host factors and its utilization may therefore have future implications for diagnosing C. trachomatis-induced infertility. We outline the epidemiological situation regarding C. trachomatis and TFI in high-income countries. Thereupon, we review the main characteristics of the population undergoing fertility work-up and identify screening and diagnostic strategies for TFI currently in place. The Netherlands is an exemplary model for the state of the art in high-income countries. Within the framework of existing clinical approaches, we propose a scenario for the translation of relevant genome-based information into triage of infertile women, with the objective of implementing genetic profiling in the routine investigation of TFI. Furthermore, we describe the state of the art in relevant gene- and single nucleotide polymorphism (SNP) based clinical prediction models and place our perspectives in the context of these applications. We conclude that the introduction of a genetic test of proven validity into the assessment of TFI should help reduce patient burden from invasive and costly examinations by achieving a more precise risk stratification.

An Integrated Care Model With Implementation Roadmap to Improve Chlamydia trachomatis Management and Control in India

Chlamydia trachomatis is the world's most prevalent bacterial Sexually Transmitted infection (STI). It is associated with a wide range of health consequences and sequelae in both the short and long term. Enhanced control of urogenital C. trachomatis infection is particularly important in low- and middle-income countries such as India, where most of the burden goes unnoticed and where limited systematic data is available to gauge the current situation. The World Health Organization (WHO) recently issued its latest strategy on STIs, which is aligned with the achievement of the Sustainable Development Goals (SDGs). Taking the WHO framework into account; this paper puts forward an integrated care model to strengthen the management and control of C. trachomatis in India. The model is compiled of five key components of STI management (awareness, prevention diagnosis, treatment and follow-up). The model considers barriers to effective C. trachomatis control into account. The barriers are discussed and compiled into different categories. A roadmap for the implementation of other similar models to enhance C. trachomatis control in the future is provided.

Differential Regulation of T-cell mediated anti-tumor memory and cross-protection against the same tumor in lungs versus skin

A major advantage of immunotherapy of cancer is that effector cells induced at one site should be able to kill metastatic cancer cells in other sites or tissues. However, different tissues have unique immune components, and very little is known about whether effector T cells induced against tumors in one tissue can work against the same tumors in other tissues. Here, we used CT26 murine tumor models to investigate anti-tumor immune responses in the skin and lungs and characterized cross-protection between the two tissues. Blockade of the function of Treg cells with anti-CD25 allowed for T cell-dependent rejection of s.c. tumors. When these mice were simultaneously inoculated i.v. with CT26, they also rejected tumors in the lung. Interestingly, in the absence of s.c. tumors, anti-CD25 treatment alone had no effect on lung tumor growth. These observations suggested that T cell-mediated anti-tumor protective immunity induced against s.c. tumors can also protect against lung metastases of the same tumors. In contrast, NKT cell-deficiency in CD1d^-/- mice conferred significant protection against lung tumors but had no effect on the growth of tumors in the skin, and tumor rejection induced against the CT26 in the lung did not confer protection for the same tumor cells in the skin. Thus, effector cells against the same tumor do not work in all tissues, and the induction site of the effector T cells is critical to control metastasis. Further, the regulation of tumor immunity may be different for the same tumor in different anatomical locations.

Abstract 1015: Directionality of T-cell-mediated cross-protection against the same tumor in lungs versus skin

Immunotherapy is a new pillar of cancer therapy. One theoretical advantage of immunotherapy of cancer is that effector cells induced at one site should be able to kill metastatic cancer cells in other sites or tissues. On the other hand, it has been recognized that each tissue has unique immune components that play critical roles in protection against pathogens. However, very little is known whether effector T cells induced against tumors in one tissue can work against the same tumors in other tissues. To address this question, we compared the effect of effector cells induced against the same tumor cells growing in either the skin or the lung by using CT26 murine tumor models. Rejection of s.c. CT26 tumors was achieved by pretreatment with anti-CD25, which blocks the function of Treg cells. Both CD4 and CD8 T cells were necessary for the protection. When anti-CD25-pretreated mice challenged with s.c. CT26 were simultaneously inoculated i.v. with CT26, they also rejected tumors in the lung, while anti-CD25-pretreated mice without s.c. CT26 did not. This observation suggested that T cell mediated anti-tumor protective immunity induced against s.c. tumors can also protect against lung metastases of the same tumors. In contrast to Treg depletion which allowed for the induction of protective immunity in the s.c. tumor model, NKT cell-deficiency in CD1d KO mice induced significant CD8 T cell-mediated protection against lung metastasis of CT26 but had no effect on the growth of s.c. CT26 tumors. When CD1d KO mice rejecting i.v. CT26 were simultaneously challenged with s.c. CT26, the development of s.c. tumors was not affected, indicating that tumor rejection induced against the CT26 in the lung did not confer protection for the same tumor cells in the skin. Since the protection against CT26 in the lung in CD1d KO mice is mediated by CD8 T cells, we transferred T cells from CD1d KO mice inoculated i.v. with CT26 into RAG1 KO recipients, and challenged the recipient mice with the CT26 tumor cells. The recipient RAG1 KO mice were highly resistant to CT26 inoculated i.v. but not s.c. confirming that the CD8 T cells protective in the lung are not protective in the skin. These data

indicate the effector cells against the same tumor do not work in all tissues, and the induction site of the effector T cells is critical to control metastasis.

Citation Format: Jessica J. O'Konek, Elena Ambrosino, Anja Bloom, Liat Izhak, Jay A. Berzofsky, Masaki Terabe. Directionality of T-cell-mediated cross-protection against the same tumor in lungs versus skin [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2017; 2017 Apr 1-5; Washington, DC. Philadelphia (PA): AACR; Cancer Res 2017;77(13 Suppl):Abstract nr 1015. doi:10.1158/1538-7445.AM2017-1015

The attitudes of Dutch fertility specialists towards the addition of genetic testing in screening of tubal factor infertility

BACKGROUND

This study aims to identify elements perceived by Dutch fertility specialists as barriers and facilitators for the introduction of genetic testing, and their attitudes towards the use of genetic information. The genetic test would be implemented in routine screening for tubal pathology and identifies SNPs relevant for the immune response causing tubal pathology.

METHODS

Experienced reproductive specialists working in Dutch Academic Hospitals were interviewed. Based on the results of four interviews a questionnaire was developed and used to survey medical doctors in six out of eight Dutch Academic hospitals.

RESULTS

60.4% (n=91) stated that the addition of genetic markers to the Chlamydia trachomatis antibody test (CAT) in screening for tubal pathology would increase screening accuracy. 68.2% (n=90) agreed they would require additional training on clinical genetics. Clinical utility (91.2%, n=91) and cost-effectiveness (95.6%, n=91) were recognized by the respondents as important factors in gaining support for the new screening strategy.

CONCLUSION

In summary, respondents showed a positive attitude towards the implementation of a genetic test combined with CAT for tubal factor infertility (TFI) screening. To gain their support the majority of respondents agreed that clinical utility, specifically cost-effectiveness, is an important factor. Comprehensive research about economic implications and utility regarding the introduction of genomic markers should be the next step in the implementation strategy. Furthermore, education and training would need to be developed and offered to fertility care professionals about genetic markers, their interpretation, and implications for clinical decision-making.

The impact of personalized medicine of Type 2 diabetes mellitus in the global health context

Advances in the fields of genomic sciences have given rise to personalized medicine. This new paradigm draws upon a patient's genetic and metabolic makeup in order to tailor diagnostics and treatment. Personalized medicine holds remarkable promises to improve prevention and management of chronic diseases of global relevance, such as Type 2 diabetes mellitus (T2DM). This review article aims at summarizing the evidence from genome-based sciences on T2DM risk and management in different populations and in the Global Health context. Opinions from leading experts in the field were also included. Based on these findings, strengths and weaknesses of personalized approach to T2DM in a global context are delineated. Implications for future research and implementation on that subject are discussed.

A surgical algorithm for partial or total eyebrow flap reconstruction

The eyebrow is one of the five aesthetic sub-units of the forehead and it plays a key role in communication and facial expression. Reconstruction of this region can be challenging. Several methods have been described, mostly based on the size of the defect and on the part of the eyebrow that they involve. We describe our experience in 48 patients underlining the importance of a surgical algorithm for repairing eyebrow defects.

Abstract 460: Delicate balance among three types of T cells in concurrent regulation of tumor immunity

Various immunosuppressive cells, such as Tregs and type II NKT cells, mediate the immune regulation of cancer. Many studies have demonstrated the importance of regulatory cells; however, it is still not clear why different suppressive cells play a dominant role in different models. Here, we examined the relative role of two suppressors - Tregs and type II NKT cells – in a subcutaneous CT26 tumor model in three strains of mice: wild-type, NKT cell-deficient CD1dKO mice and Jα18KO, which lack type I NKT cells but still retain type II NKT cells. Tumors grew in all three strains, but Treg blockade by anti-CD25 mAb (PC61) led to tumor rejection in WT and CD1dKO but not in Jα18KO mice, suggesting that in Jα18KO mice, Tregs are not necessary for immune suppression. We hypothesized that cross regulation between type I and type II NKT cells in wild-type mice leaves Treg cells as primary suppressors, whereas in mice lacking type I NKT cells, unopposed type II NKT cells can suppress tumor immunity even when Tregs are blocked. We confirmed this hypothesis in PC61-treated Jα18KO mice by blocking type II NKT cells using anti-CD1d mAb (1B1) or by adoptive transfer of type I NKT cells combined with Treg blockade. These results support our hypothesis that it is necessary to block both suppressors, type II NKT cells and Tregs, in order to achieve protection. Also, activation of type II NKT cells by sulfatide in PC61-treated wild-type mice abrogated the protective effect of Treg blockade, indicating that shifting the balance between the two types of NKT cells toward immunosuppressive type II NKT cell dominance suppresses tumor immunity even in the absence of Tregs. We conclude that both Tregs and type II NKT cells can concurrently suppress tumor immunity and the balance between these is controlled in part by a third T cell, the type I NKT cell, regulating the regulators. Finally as cancer patients often have deficient type I NKT cell function somewhat like the Jα18KO mice, managing this delicate balance among three T cells may be critical for the success of immunotherapy of human cancer.

Citation Format: Liat Izhak, Elena Ambrosino, Jessica J. O'Konek, Shingo Kato, Stanley T. Parish, Zheng Xia, David Venzon, Jay A. Berzofsky, Masaki Terabe. Delicate balance among three types of T cells in concurrent regulation of tumor immunity. [abstract]. In: Proceedings of the 104th Annual Meeting of the American Association for Cancer Research; 2013 Apr 6-10; Washington, DC. Philadelphia (PA): AACR; Cancer Res 2013;73(8 Suppl):Abstract nr 460. doi:10.1158/1538-7445.AM2013-460

Chlamydia trachomatis infections and subfertility: opportunities to translate host pathogen genomic data into public health

Chlamydia trachomatis (CT) infections in women can result in tubal pathology (TP). Worldwide 10-15% of all couples are subfertile, meaning they did not get pregnant after 1 year. Part of the routine subfertility diagnostics is the Chlamydia Antibody Test (CAT) to decide for laparoscopy or not in order to diagnose TP. The CAT positive and negative predictive value is such that many unneeded laparoscopies are done and many TP cases are missed. Addition of host genetic markers related to infection susceptibility and severity could potentially improve the clinical management of couples who suffer from subfertility. In the present study, the potential translational and clinical value of adding diagnostic host genetic marker profiles on the basis of infection and inflammation to the current clinical management of subfertility was investigated. This review provides an overview of the current state of the art of host genetic markers in relation to CT infection, proposes a new clinical diagnostic approach, and investigates how the Learning-Adapting-Leveling model (LAL, a public health genomic (PHG) model) can be of value and provide insight to see whether these host genetic markers can be translated into public health. This review shows that the preliminary basis of adding host genetic marker profiles to the current diagnostic procedures of subfertility is present but has to be further developed before implementation into health care can be achieved. CT infection is an example in the field of PHG with potential diagnostic to be taken up in the future in the field of subfertility diagnosis with a time line for integration to be dependent on enhanced participation of many stakeholders in the field of PHG which could be advanced through the LAL model.

Concepts for the translation of genome-based innovations into public health: a comprehensive overview

Recent vast and rapid development of genome-related sciences is followed by the development of different assessment techniques or attempts to adapt the existing ones. The aim of this article is to give an overview of existing concepts for the assessment and translation of innovations into healthcare, applying a descriptive analysis of their present use by public health specialists and policy makers. The international literature review identified eight concepts including Health Technology Assessment, analytic validity, clinical validity, clinical utility, ethical, legal and social implications, Public Health Wheel and others. This study gives an overview of these concepts (including the level of current use) applying a descriptive analysis of their present use by public health specialists and policy makers. Despite the heterogeneity of the analyzed concepts and difference in use in everyday healthcare practice, the cross-integration of these concepts is important in order to improve translation speed and quality. Finally, some recommendations are made regarding the most applicable translational concepts.

Delicate balance among three types of T cells in concurrent regulation of tumor immunity

The nature of the regulatory cell types that dominate in any given tumor is not understood at present. Here, we addressed this question for regulatory T cells (Treg) and type II natural killer T (NKT) cells in syngeneic models of colorectal and renal cancer. In mice with both type I and II NKT cells, or in mice with neither type of NKT cell, Treg depletion was sufficient to protect against tumor outgrowth. Surprisingly, in mice lacking only type I NKT cells, Treg blockade was insufficient for protection. Thus, we hypothesized that type II NKT cells may be neutralized by type I NKT cells, leaving Tregs as the primary suppressor, whereas in mice lacking type I NKT cells, unopposed type II NKT cells could suppress tumor immunity even when Tregs were blocked. We confirmed this hypothesis in 3 ways by reconstituting type I NKT cells as well as selectively blocking or activating type II NKT cells with antibody or the agonist sulfatide, respectively. In this manner, we showed that blockade of both type II NKT cells and Tregs is necessary to abrogate suppression of tumor immunity, but a third cell, the type I NKT cell, determines the balance between these regulatory mechanisms. As patients with cancer often have deficient type I NKT cell function, managing this delicate balance among 3 T-cell subsets may be critical for the success of immunotherapy for human cancer.

A new public health genomics model for common complex diseases, with an application to common behavioral disorders

AIM

In the light of common forms of gene-environment interplay, particularly epigenomics and ecogenetics, the incorporation of envirome data into public health genomics models becomes necessary. Developing and restructuring public health genomics models is essential within the context of common complex diseases.

MATERIALS & METHODS

We developed a novel theoretical model integrating a gene-environment interaction paradigm into public health genomics, which integrates four main sources of data: personal genome data, personal envirome data, molecular genetic/genomic evidence and environmental factors implicated in gene-environment interactions underlying common complex disease phenotypes. Collectively, this knowledge is fed into public health policy development.

RESULTS

This model is the first public health genomics model that incorporates gene-environment interactions within the context of common complex disorders, and is applied to behavioral conditions.

CONCLUSION

Our model proposes, for the first time, an understanding of behavioral disorders from the genomic perspective, combining it with known environmental factors within the framework of public health. Application of this model will enable evidence-based behavioral interventions at the public health level and facilitate genome-based public health policy development for behavioral conditions.

Abstract 4746: Type I NKT cells mediate anti-tumor immunity through a TNF-α- and NOS-dependent pathway when stimulated with β-ManCer

CD1d-restricted type I NKT cells have been shown to play a critical role in the induction of tumor immunity by producing IFN-γ, which activates effector arms such as NK cells and CD8+ T cells. It has been considered that IFN-γ is necessary for type I NKT cell-induced tumor immunity. In this study, we show that type I NKT cells can induce strong tumor immunity through an IFN-γ-independent pathway when activated with a new type of agonistic antigen, β-mannosylceramide (β-ManCer). The protection induced by β-ManCer treatment was completely abrogated in type I NKT cell deficient Jα18 KO mice. With the observations that in vitro activation of type I NKT cells by β-ManCer was blocked by anti-CD1d blocking monoclonal antibody and that β-ManCer-loaded CD1d dimers bind to type I NKT cells and stimulate type I NKT cell hybridomas in an APC-free system, we concluded that recognition of CD1d presented β-ManCer by a TCR of type I NKT cells is necessary for the protection. Surprisingly β-ManCer-induced protection was not abrogated in IFN-γ deficient mice, which is in contrast with the protection induced by a prototypic agonist α-galactosylceramide (α-GalCer). Instead, β-ManCer-induced protection was dependent on nitric oxide synthase (NOS) and TNF-α since blockade of either completely abrogated the protection while the blockade did not affect protection induced by α-GalCer. The conclusion that NKT cells activated with β-ManCer utilize a different pathway from that used by the cells activated with α-GalCer to enhance tumor immunity was confirmed with the observation that the combination of both antigens synergistically enhanced tumor immunity when suboptimal doses of each were used. These data demonstrate that NKT cells mediate tumor immunity through a TNF-α- and NOS-dependent pathway when stimulated with β-ManCer and that β-ManCer represents a new class of type I NKT cell agonist. Since we observed that human type I NKT cells also can be activated by β-ManCer, β-ManCer may provide a new intervention against cancer.

Citation Format: {Authors}. {Abstract title} [abstract]. In: Proceedings of the 102nd Annual Meeting of the American Association for Cancer Research; 2011 Apr 2-6; Orlando, FL. Philadelphia (PA): AACR; Cancer Res 2011;71(8 Suppl):Abstract nr 4746. doi:10.1158/1538-7445.AM2011-4746

Mouse and human iNKT cell agonist β-mannosylceramide reveals a distinct mechanism of tumor immunity

Type 1 or invariant NKT (iNKT) cell agonists, epitomized by α-galactosylceramide, protect against cancer largely by IFN-γ-dependent mechanisms. Here we describe what we believe to be a novel IFN-γ-independent mechanism induced by β-mannosylceramide, which also defines a potentially new class of iNKT cell agonist, with an unusual β-linked sugar. Like α-galactosylceramide, β-mannosylceramide directly activates iNKT cells from both mice and humans. In contrast to α-galactosylceramide, protection by β-mannosylceramide was completely dependent on NOS and TNF-α, neither of which was required to achieve protection with α-galactosylceramide. Moreover, at doses too low for either alone to protect, β-mannosylceramide synergized with α-galactosylceramide to protect mice against tumors. These results suggest that treatment with β-mannosylceramide provides a distinct mechanism of tumor protection that may allow efficacy where other agonists have failed. Furthermore, the ability of β-mannosylceramide to synergize with α-galactosylceramide suggests treatment with this class of iNKT agonist may provide protection against tumors in humans.

A multiplex assay for the simultaneous detection of antibodies against 15 Plasmodium falciparum and Anopheles gambiae saliva antigens

BACKGROUND

Assessment exposure and immunity to malaria is an important step in the fight against the disease. Increased malaria infection in non-immune travellers under anti-malarial chemoprophylaxis, as well as the implementation of malaria elimination programmes in endemic countries, raises new issues that pertain to these processes. Notably, monitoring malaria immunity has become more difficult in individuals showing low antibody (Ab) responses or taking medications against the Plasmodium falciparum blood stages. Commonly available techniques in malaria seroepidemiology have limited sensitivity, both against pre-erythrocytic, as against blood stages of the parasite. Thus, the aim of this study was to develop a sensitive tool to assess the exposure to malaria or to bites from the vector Anopheles gambiae, despite anti-malarial prophylactic treatment.

METHODS

Ab responses to 13 pre-erythrocytic P. falciparum-specific peptides derived from the proteins Lsa1, Lsa3, Glurp, Salsa, Trap, Starp, CSP and Pf11.1, and to 2 peptides specific for the Anopheles gambiae saliva protein gSG6 were tested. In this study, 253 individuals from three Senegalese areas with different transmission intensities and 124 European travellers exposed to malaria during a short period of time were included.

RESULTS

The multiplex assay was optimized for most but not all of the antigens. It was rapid, reproducible and required a small volume of serum. Proportions of Ab-positive individuals, Ab levels and the mean number of antigens (Ags) recognized by each individual increased significantly with increases in the level of malaria exposure.

CONCLUSION

The multiplex assay developed here provides a useful tool to evaluate immune responses to multiple Ags in large populations, even when only small amounts of serum are available, or Ab titres are low, as in case of travellers. Finally, the relationship of Ab responses with malaria endemicity levels provides a way to monitor exposure in differentially exposed autochthonous individuals from various endemicity areas, as well as in travellers who are not immune, thus indirectly assessing the parasite transmission and malaria risk in the new eradication era.

Erbb2 DNA vaccine combined with regulatory T cell deletion enhances antibody response and reveals latent low-avidity T cells: potential and limits of its therapeutic efficacy

Rat (r)Erbb2 transgenic BALB-neuT mice genetically predestined to develop multiple invasive carcinomas allow an assessment of the potential of a vaccine against the stages of cancer progression. Because of rErbb2 expression in the thymus and its overexpression in the mammary gland, CD8(+) T cell clones reacting at high avidity with dominant rErbb2 epitopes are deleted in these mice. In BALB-neuT mice with diffuse and invasive in situ lesions and almost palpable carcinomas, a temporary regulatory T cells depletion combined with anti-rErbb2 vaccine markedly enhanced the anti-rErbb2 Ab response and allowed the expansion of latent pools of low-avidity CD8(+) T cells bearing TCRs repertoire reacting with the rErbb2 dominant peptide. This combination of a higher Ab response and activation of a low-avidity cytotoxic response persistently blocked tumor progression at stages in which the vaccine alone was ineffective. However, when diffuse and invasive microscopic cancers become almost palpable, this combination was no longer able to secure a significant extension of mice survival.

Abstract 5613: Beta-mannosylceramide: a novel NKT cell agonist which synergizes with alpha-galactocylceramide to induce protection against tumors

Type I natural killer T (NKT) cells are a unique subset of T cells which express phenotypic and functional characteristics of both NK cells and T cells. NKT cells recognize glycolipid antigens presented by the non-classical MHC-like molecule CD1d. Upon stimulation with the prototypical type I NKT cell antigen α-galactosylceramide (α-GalCer), type I NKT cells promote tumor immunity through IFN-γ-dependent mechanims. In this study the ability of glycosylceramides with alterations of the sugar moiety to induce anti-tumor immune responses in an in vivo model of CT26 colon carcinoma metastasis to lungs of BALB/c mice was investigated. β-mannosylceramide (β-ManCer) induced strong tumor protection, while α-mannosylceramide and α-fucosylceramide did not. This is the first evidence of a glycosylceramide with a β-linked sugar moiety capable of inducing significant NKT cell-dependent anti-tumor immunity. We also confirmed that β-ManCer could protect at least as well as α-GalCer in a model of B16F10 melanoma lung metastasis in C57BL/6 mice. Interestingly, β-ManCer induced little cytokine production and retained protective activity in IFN-γ KO mice, unlike α-GalCer analogs which where completely dependent upon IFN-γ. The protection did not require CD8+ T cells, and was largely independent of NK cells. Blockade of nitric oxide synthase or TNF-α significantly reversed the β-ManCer-induced protection but had no effect on tumor protection for the α-GalCer analogs. Thus, contrary to α-GalCer, β-ManCer protects through a novel TNF-α and NOS-dependent, IFN-γ-independent mechanism. Consistent with the conclusion that β-ManCer and α-GalCer induce tumor immunity by distinct mechanisms, simultaneous administration of sub-therapeutic doses of these glycolipids resulted in synergistic reduction in the number of lung metastases. The distinct mechanism of action and ability to synergize with α-GalCer may suggest that β-ManCer represents a new class of NKT agonists with novel clinical applications.

Citation Format: {Authors}. {Abstract title} [abstract]. In: Proceedings of the 101st Annual Meeting of the American Association for Cancer Research; 2010 Apr 17-21; Washington, DC. Philadelphia (PA): AACR; Cancer Res 2010;70(8 Suppl):Abstract nr 5613.

Beta-mannosylceramide represents a new class of NKT agonists that induces tumor immunity by a novel IFN-γ-independent mechanism. (89.7)

Type I NKT cells are a unique lymphocyte population which recognize lipid antigens presented by the non-classical MHC-like molecule CD1d. Activation of type I NKT cells by α-galactosylceramide (α-GC) induces tumor immunity by IFN-γ dependent mechanisms. In this study, we characterized how modifications of the sugar head group of α-GC impacted tumor protection in an in vivo mouse model of lung metastasis. β-mannosylceramide (β-ManCer), but not α-mannosylceramide or α-fucosylceramide, induced strong type I NKT cell-dependent tumor immunity. Because this is the first report of a β-linked glycosylcermide capable of inducing significant type I NKT cell-mediated tumor protection, we further characterized the mechanism by which β-ManCer induced tumor elimination. Interestingly, unlike α-GC and its analogs which protected through IFN-γ dependent mechanisms, β-ManCer induced very little cytokine production both in vitro and in vivo and retained protection in the absence of IFN-γ. Rather, β-ManCer protected through a TNF-α and nitric oxide synthase-dependent mechanism novel for NKT cells. Simultaneous administration of sub-therapeutic doses of β-ManCer and α-GC resulted in synergistic reduction in tumor burden, supporting the conclusion that these glycolipids work through different mechanisms. The distinct mechanism of action of β-ManCer and its ability to synergize with α-GC suggest that β-ManCer is the first representative of a new class of type I NKT cell agonists.

Blockade of TGF-beta enhances tumor vaccine efficacy mediated by CD8(+) T cells

Though TGF-beta inhibition enhances antitumor immunity mediated by CD8(+) T cells in several tumor models, it is not always sufficient for rejection of tumors. In this study, to maximize the antitumor effect of TGF-beta blockade, we tested the effect of anti-TGF-beta combined with an irradiated tumor vaccine in a subcutaneous CT26 colon carcinoma tumor model. The irradiated tumor cell vaccine alone in prophylactic setting significantly delayed tumor growth, whereas anti-TGF-beta antibodies alone did not show any antitumor effect. However, tumor growth was inhibited significantly more in vaccinated mice treated with anti-TGF-beta antibodies compared to vaccinated mice without anti-TGF-beta, suggesting that anti-TGF-beta synergistically enhanced irradiated tumor vaccine efficacy. CD8(+) T-cell depletion completely abrogated the vaccine efficacy, and so protection required CD8(+) T cells. Depletion of CD25(+) T regulatory cells led to the almost complete rejection of tumors without the vaccine, whereas anti-TGF-beta did not change the number of CD25(+) T regulatory cells in unvaccinated and vaccinated mice. Though the abrogation of CD1d-restricted NKT cells, which have been reported to induce TGF-beta production by MDSC through an IL-13-IL-4R-STAT6 pathway, partially enhanced antitumor immunity regardless of vaccination, abrogation of the NKT cell-IL-13-IL-4R-STAT-6 immunoregulatory pathway did not enhance vaccine efficacy. Taken together, these data indicated that anti-TGF-beta enhances efficacy of a prophylactic vaccine in normal individuals despite their not having the elevated TGF-beta levels found in patients with cancer and that the effect is not dependent on TGF-beta solely from CD4(+)CD25(+) T regulatory cells or the NKT cell-IL-13-IL-4R-STAT-6 immunoregulatory pathway.

Synergistic enhancement of CD8+ T cell-mediated tumor vaccine efficacy by an anti-transforming growth factor-beta monoclonal antibody

PURPOSE

Transforming growth factor-beta (TGF-beta) is an immunosuppressive cytokine, having direct suppressive activity against conventional CD4(+) and CD8(+)T cells and natural killer cells, thereby inhibiting tumor immunosurveillance. Here, we investigated possible synergy between anti-TGF-beta (1D11) and a peptide vaccine on induction of antitumor immunity, and the mechanisms accounting for synergistic efficacy.

EXPERIMENTAL DESIGN

The effect of combination treatment with a peptide vaccine and anti-TGF-beta was examined in a subcutaneous TC1 tumor model, as well as the mechanisms of protection induced by this treatment.

RESULTS

Anti-TGF-beta significantly and synergistically improved vaccine efficacy as measured by reduction in primary tumor growth, although anti-TGF-beta alone had no impact. The number of tumor antigen-specific CTL with high functional avidity as measured by IFN-gamma production and lytic activity was significantly increased in vaccinated mice by TGF-beta neutralization. Although TGF-beta is known to play a critical role in CD4(+)Foxp3(+) Treg cells, Treg depletion/suppression by an anti-CD25 monoclonal antibody (PC61) before tumor challenge did not enhance vaccine efficacy, and adding anti-TGF-beta did not affect Treg numbers in lymph nodes or tumors or their function. Also, TGF-beta neutralization had no effect on interleukin-17-producing T cells, which are induced by TGF-beta and interleukin-6. Absence of type II NKT cells, which induce myeloid cells to produce TGF-beta, was not sufficient to eliminate all sources of suppressive TGF-beta. Finally, the synergistic protection induced by anti-TGF-beta vaccine augmentation was mediated by CD8(+) T cells since anti-CD8 treatment completely abrogated the effect.

CONCLUSIONS

These results suggest that TGF-beta blockade may be useful for enhancing cancer vaccine efficacy.

Regulation of tumor immunity: the role of NKT cells

BACKGROUND

Tumor immunosurveillance is a part of the dynamic process of interaction between abnormal cells and the host immune system. Tumor immunosurveillance is actively and continuously regulated in both positive and negative ways. Natural killer T (NKT) cells are cells that have been shown to play a role in both positive and negative regulation of tumor immunosurveillance. Recent studies suggest that NKT cells are a heterogeneous cell population with multiple subsets with distinct functions.

OBJECTIVE

This review discusses the functions of those NKT cell subsets in regulating tumor immunity and potential interactions or counter-regulation among the NKT cell subsets.

METHOD

Selected literature is reviewed.

CONCLUSION

Manipulation of the balance among those subsets may provide new modes of intervention for tumor immunotherapy.

Cross-regulation between type I and type II NKT cells in regulating tumor immunity: a new immunoregulatory axis

Negative immunoregulation is a major barrier to successful cancer immunotherapy. The NKT cell is known to be one such regulator. In this study we explored the roles of and interaction between the classical type I NKT cell and the poorly understood type II NKT cell in the regulation of tumor immunity. Selective stimulation of type II NKT cells suppressed immunosurveillance, whereas stimulation of type I NKT cells protected against tumor growth even when responses were relatively skewed toward Th2 cytokines. When both were stimulated simultaneously, type II NKT cells appeared to suppress the activation in vitro and protective effect in vivo of type I NKT cells. In the absence of type I, suppression by type II NKT cells increased, suggesting that type I cells reduce the suppressive effect of type II NKT cells. Thus, in tumor immunity type I and type II NKT cells have opposite and counteractive roles and define a new immunoregulatory axis. Alteration of the balance between the protective type I and the suppressive type II NKT cell may be exploited for therapeutic intervention in cancer.

Type II NKT cells suppress tumor immunosurveillance enhanced by type I NKT cells (50.16)

NKT cells are a T cell subset that recognizes glycolipid antigens presented by CD1d. They consist of 2 subsets: the widely studied type I expressing a canonical TCR, Vα14Jα18, and a little known type II of non-Vα14Jα18 NKT cells. Here, we examined the role of type I and II NKT cells in the regulation of tumor immunosurveillance. Jα18 KO mice, which lack type I but retain type II NKT cells, had a significantly larger tumor burden of CT26 tumor injected i.v. than wild-type mice early in tumor growth. This result suggested that the absence of type I NKT cells allows type II NKT cells to further suppress tumor immunosurveillance compared to wild-type mice that have both types of NKT cells. The role of NKT cell subsets was examined by stimulating them with antigens that specifically activate either type I or type II NKT cells. Mice treated with type I NKT cell agonist α-galactosylceramide or the weaker agonist OCH almost completely rejected tumor. In contrast, mice treated with a single dose of type II NKT cell-stimulating sulfatide had significantly increased tumor burden. Simultaneous stimulation of both types of NKT cells in vivo significantly suppressed the protective effect of type I NKT cell stimulation. Overall, the results suggested that stimulation of type I NKT cells promotes tumor immunosurveillance, whereas stimulation of type II NKT cells suppresses, and that type II NKT cells suppress type I NKT cell activity.

[Polycystic ovary syndrome: an example of obesity-related cardiovascular complication affecting young women]

Polycystic ovary syndrome (PCOS) is a good example of obesity-related cardiovascular complication affecting young women. PCOS is not only considered a reproductive problem but rather represents a complex endocrine, multifaceted syndrome with important health implications. Several evidences suggest an increased cardiovascular risk of cardiovascular disease associated with this syndrome, characterized by an impairment of heart structure and function, endothelial dysfunction and lipid abnormalities. All these features, probably linked to insulin-resistance, are often present in obese PCOS patients. Cardiovascular abnormalities represent important long-term sequelae of PCOS that need further investigations.

[GnRH agonists and antagonists in the preoperative therapy of uterine fibroids: literature review]

Uterine leiomyomas are the most frequent gynecological benign tumors. Their growth is regulated by ovarian steroids, therefore a hypoestrogenic state, like menopause or pharmacologically induced pseudo-menopause by GnRH-agonists or GnRH-antagonists, is associated with the decrease of their volume. This volume reduction allows a less invasive surgical procedure and may reduce the amount of blood loss during surgery. Therefore, GnRH-agonists and antagonists are used in presurgical treatment of uterine fibromatosis. This review analyses the effects of GnRH-agonists and GnRH-antagonists therapies. GnRH-agonists produce a down-regulation of GnRH receptor, while GnRH-antagonists compete with endogenous GnRH for pituitary binding sites. Due to the lack of any intrinsic activity of GnRH-antagonists, the characteristic initial flare-up observed with GnRH-agonist treatment is absent. So, GnRH-antagonists rapidly suppress gonadotropin release within 4-8 h, while GnRH-agonists show clinical effects after 2 or 3 weeks of treatment. GnRH-antagonist activity is dose-dependent so it is possible to adjust the dose to obtain the proper levels of inhibition. The GnRH-agonist presurgical treatment usually is a short-term therapy (3-6 months), because it causes side-effects like menopause symptoms. GnRH-antagonist clinical effects can be achieved with a short-time therapy too. Their side-effects include flushes and head-ache. After stopping therapy with both drugs, leiomyomas rapidly achieve their original size while side-effects disappear. Further studies are necessary to establish the use of GnRH-antagonists in leiomyomas therapy, but in Italy this is not possible because their use is not approved.

Immunosurveillance of Erbb2 Carcinogenesis in Transgenic Mice Is Concealed by a Dominant Regulatory T-Cell Self-Tolerance

To assess the role of CD4(+)CD25(+)Foxp3(+) regulatory T (Treg) cells in overcoming immunosurveillance of Erbb2 (HER-2/neu) mammary lesions, we studied the effects of their sustained removal in BALB/c female mice made transgenic for the rat Erbb2 (r-Erbb2) oncogene (BALB-neuT mice), which develop multiple mammary carcinomas. During the progression of these lesions, Treg cells expand in the spleen, tumor draining lymph nodes, and tumors. Repeated administration of anti-CD25 antibodies extends tumor-free survival, reduces carcinoma multiplicity, and leads to the manifestation of a natural antibody and CTL-mediated reactivity against r-Erbb2. Loss of Foxp3(+) Treg cells during anti-CD25 treatment remarkably caused the disappearance of Gr1(+) immature myeloid cells, suggesting a cross-talk between these two inhibitory immune cell types. Treg cell expansion associated with r-Erbb2 overexpression may be seen as a physiologic response to dampen the immune reaction elicited by local anomalous overexpression of a self-antigen.

Timely DNA vaccine combined with systemic IL-12 prevents parotid carcinomas before a dominant-negative p53 makes their growth independent of HER-2/neu expression

Double transgenic mice overexpressing the transforming rat HER-2/neu oncogene and the mutated p53, with both dominant-negative and a gain-of-function properties, display early aggressive and metastasizing parotid tumors. Multiple acinar and ductal hyperplasia foci overexpressing the HER-2/neu gene product are evident at wk 5 and progress to poorly differentiated carcinoma by wk 7. Mice die before wk 18 with invasive carcinomas and multiple metastases that no longer express HER-2/neu. A combination of repeated electroporations of plasmids coding for the extracellular and transmembrane domains of the rat HER-2/neu receptor with systemic IL-12 administrations started when the parotids that present diffuse hyperplasia protected all female and 50% of the male mice until the close of the experiment at wk 40. This combined treatment began when multifocal in situ carcinomas that were already present cured 33% of the females and 25% of the males. The most prominent immunologic features associated with the antitumor protection were the production of high titers of anti-HER-2/neu Abs and the nonappearance of cell-mediated cytotoxic reactivity. In conclusion, anti-HER-2/neu vaccination combined with systemic IL-12 control parotid carcinomas as far as p53 mutation makes their growth independent of HER-2/neu expression.

p130Cas as a new regulator of mammary epithelial cell proliferation, survival, and HER2-neu oncogene-dependent breast tumorigenesis

To investigate the mechanisms through which p130Cas adaptor protein is linked to tumorigenesis, we generated mouse mammary tumor virus (MMTV)-p130Cas mice overexpressing p130Cas in the mammary gland. MMTVp130Cas transgenic mice are characterized by extensive mammary epithelial hyperplasia during development and pregnancy and by delayed involution at the end of lactation. These phenotypes are associated with activation of Src kinase, extracellular signal-regulated kinase 1/2, mitogen-activated protein kinase, and Akt pathways, leading to an increased rate of proliferation and a decreased apoptosis. A double-transgenic line derived from crossing MMTV-p130Cas with MMTV-HER2-Neu mice expressing the activated form of the HER2-Neu oncogene develops multifocal mammary tumors with a significantly shorter latency than the HER2-Neu parental strain alone. Mammary epithelial cells isolated from tumors of double-transgenic mice display increased tyrosine phosphorylation, c-Src, and Akt activation compared with cells derived from HER2-Neu tumors. In addition, p130Cas down-regulation by RNA interference increases apoptosis in HER2-Neu-expressing cells, indicating that p130Cas regulates cell survival. Consistently with the double-transgenic mice model, p130Cas is overexpressed in a significant subset of human breast cancers and high levels of p130Cas in association with HER2 expression correlate with elevated proliferation. These findings provide evidences for a role of p130Cas as a positive regulator of both proliferation and survival in normal and transformed mammary epithelial cells. Its overexpression contributes to HER2-Neu-induced breast tumorigenesis, thus identifying this protein as a putative target for clinical therapy.

A DNA vaccine targeting angiomotin inhibits angiogenesis and suppresses tumor growth

Endogenous angiogenesis inhibitors have shown promise in preclinical trials, but clinical use has been hindered by low half-life in circulation and high production costs. Here, we describe a strategy that targets the angiostatin receptor angiomotin (Amot) by DNA vaccination. The vaccination procedure generated antibodies that detected Amot on the endothelial cell surface. Purified Ig bound to the endothelial cell membrane and inhibited endothelial cell migration. In vivo, DNA vaccination blocked angiogenesis in the matrigel plug assay and prevented growth of transplanted tumors for up to 150 days. We further demonstrate that a combination of DNA vaccines encoding Amot and the extracellular and transmembrane domains of the human EGF receptor 2 (Her-2)/neu oncogene inhibited breast cancer progression and impaired tumor vascularization in Her-2/neu transgenic mice. No toxicity or impairment of normal blood vessels could be detected. This work shows that DNA vaccination targeting Amot may be used to mimic the effect of angiostatin.

A nonclassical non-Valpha14Jalpha18 CD1d-restricted (type II) NKT cell is sufficient for down-regulation of tumor immunosurveillance

The importance of immunoregulatory T cells has become increasingly apparent. Both CD4⁺CD25⁺ T cells and CD1d-restricted NKT cells have been reported to down-regulate tumor immunity in mouse tumor models. However, the relative roles of both T cell populations have rarely been clearly distinguished in the same tumor models. In addition, CD1d-restricted NKT cells have been reported to play a critical role not only in the down-regulation of tumor immunity but also in the promotion of the immunity. However, the explanation for these apparently opposite roles in different tumor models remains unclear. We show that in four mouse tumor models in which CD1d-restricted NKT cells play a role in suppression of tumor immunity, depletion of CD4⁺CD25⁺ T cells did not induce enhancement of immunosurveillance. Surprisingly, among the two subpopulations of CD1d-restricted NKT cells, Vα14Jα18⁺ (type I) and Vα14Jα18⁻ (type II) NKT cells, type I NKT cells were not necessary for the immune suppression. These unexpected results may now resolve the paradox in the role of CD1d-restricted NKT cells in the regulation of tumor immunity, in that type II NKT cells may be sufficient for negative regulation, whereas protection has been found to be mediated by α-galactosylceramide–responsive type I NKT cells.