Tumor-infiltrating CCR2+ inflammatory monocytes counteract specific immunotherapy.

Tumor development and progression is shaped by the tumor microenvironment (TME), a heterogeneous assembly of infiltrating and resident host cells, their secreted mediators and intercellular matrix. In this context, tumors are infiltrated by various immune cells with either pro-tumoral or anti-tumoral functions. Recently, we published our non-invasive immunization platform DIVA suitable as a therapeutic vaccination method, further optimized by repeated application (DIVA2). In our present work, we revealed the therapeutic effect of DIVA2 in an MC38 tumor model and specifically focused on the mechanisms induced in the TME after immunization. DIVA2 resulted in transient tumor control followed by an immune evasion phase within three weeks after the initial tumor inoculation. High-dimensional flow cytometry analysis and single-cell mRNA-sequencing of tumor-infiltrating leukocytes revealed cytotoxic CD8+ T cells as key players in the immune control phase. In the immune evasion phase, inflammatory CCR2+ PDL-1+ monocytes with immunosuppressive properties were recruited into the tumor leading to suppression of DIVA2-induced tumor-reactive T cells. Depletion of CCR2+ cells with specific antibodies resulted in prolonged survival revealing CCR2+ monocytes as important for tumor immune escape in the TME. In summary, the present work provides a platform for generating a strong antigen-specific primary and memory T cell immune response using the optimized transcutaneous immunization method DIVA2. This enables protection against tumors by therapeutic immune control of solid tumors and highlights the immunosuppressive influence of tumor infiltrating CCR2+ monocytes that need to be inactivated in addition for successful cancer immunotherapy.

Peptide-Decorated Degradable Polycarbonate Nanogels for Eliciting Antigen-Specific Immune Responses.

For successful therapeutic interventions in cancer immunotherapy, strong antigen-specific immune responses are required. To this end, immunostimulating cues must be combined with antigens to simultaneously arrive at antigen-presenting cells and initiate cellular immune responses. Recently, imidazoquinolines have shown their vast potential as small molecular Toll-like receptor 7/8 (TLR7/8) agonists for immunostimulation when delivered by nanocarriers. At the same time, peptide antigens are promising antigen candidates but require combination with immune-stimulating adjuvants to boost their immunogenicity and exploit their full potential. Consequently, we herein present biodegradable polycarbonate nanogels as versatile delivery system for adjuvants within the particles' core as well as for peptide antigens by surface decoration. For that purpose, orthogonally addressable multifunctional polycarbonate block copolymers were synthesized, enabling adjuvant conjugation through reactive ester chemistry and peptide decoration by strain-promoted alkyne-azide cycloaddition (SPAAC). In preparation for SPAAC, CD4+-specific peptide sequences of the model protein antigen ovalbumin were equipped with DBCO-moieties by site-selective modification at their N-terminal cysteine. With their azide groups exposed on their surface, the adjuvant-loaded nanogels were then efficiently decorated with DBCO-functional CD4+-peptides by SPAAC. In vitro evaluation of the adjuvant-loaded peptide-decorated gels then confirmed their strong immunostimulating properties as well as their high biocompatibility. Despite their covalent conjugation, the CD4+-peptide-decorated nanogels led to maturation of primary antigen-presenting cells and the downstream priming of CD4+-T cells. Subsequently, the peptide-decorated nanogels loaded with TLR7/8 agonist were successfully processed by antigen-presenting cells, enabling potent immune responses for future application in antigen-specific cancer immunotherapy.

Modulation of cellular transcriptome and proteome composition by azidohomoalanine-implications on click chemistry-based secretome analysis.

The analysis of the secretome provides important information on proteins defining intercellular communication and the recruitment and behavior of cells in specific tissues. Especially in the context of tumors, secretome data can support decisions for diagnosis and therapy. The mass spectrometry-based analysis of cell-conditioned media is widely used for the unbiased characterization of cancer secretomes in vitro. Metabolic labeling using azide-containing amino acid analogs in combination with click chemistry facilitates this type of analysis in the presence of serum, preventing serum starvation-induced effects. The modified amino acid analogs, however, are less efficiently incorporated into newly synthesized proteins and may perturb protein folding. Combining transcriptome and proteome analysis, we elucidate in detail the effects of metabolic labeling with the methionine analog azidohomoalanine (AHA) on gene and protein expression. Our data reveal that 15-39% of the proteins detected in the secretome displayed changes in transcript and protein expression induced by AHA labeling. Gene Ontology (GO) analyses indicate that metabolic labeling using AHA leads to induction of cellular stress and apoptosis-related pathways and provide first insights on how this affects the composition of the secretome on a global scale. KEY MESSAGES: Azide-containing amino acid analogs affect gene expression profiles. Azide-containing amino acid analogs influence cellular proteome. Azidohomoalanine labeling induces cellular stress and apoptotic pathways. Secretome consists of proteins with dysregulated expression profiles.

Provision of fertility services to women in same-sex relationships at Catholic and non-Catholic clinics in the United States.

INTRODUCTION: This study addressed deficient information on the provision of infertility care in obstetrics and gynecology clinics. We additionally evaluated the availability of these services based on clinic affiliations or stated sexual orientation. METHODOLOGY: We performed a national cross-sectional "mystery caller" survey of 293 general obstetrics and gynecology clinics in 2017-2018. We matched clinics identified by web-based search engine in a 1:1 ratio by Catholic hospital affiliation, after determining number of clinics based on state-population densities. A standard call script included questions regarding provision of infertility services, ovulation induction methods, and information about the caller's sexual orientation. We performed descriptive frequencies and compared responses based on hospital affiliations. RESULTS: Of the 293 clinics included, 49% were affiliated with Catholic and 17% with academic hospitals. The majority offered infertility care (85%, 248/293), and of these 97% (240/248) offered ovulation induction. Only 3% (6/240) reported they would not provide to women in same-sex relationships. Most clinics not offering infertility evaluations (43/45, 96%) cited it was outside of their scope of care and of these 33% (15/45) did not provide information for self-referral. Clinics affiliated with academic (aOR 0.23) or Catholic (aOR 0.34) hospitals were less likely to provide evaluations. Those with academic affiliation were more likely to provide information for self-referral (aOR 19.2). DISCUSSION: Most general obstetrics and gynecology practices offered appointments for infertility evaluation and ovulation induction. Clinics rarely denied services to women reporting a same-sex partnership, regardless of hospital affiliation. These findings provide reassurance to same-sex couples seeking fertility care.

Oxidative Stress Differentially Influences the Survival and Metabolism of Cells in the Melanoma Microenvironment.

The cellular composition of the tumor microenvironment, including tumor, immune, stromal, and endothelial cells, significantly influences responses to cancer therapies. In this study, we analyzed the impact of oxidative stress, induced by cold atmospheric plasma (CAP), on tumor cells, T cells, and macrophages, which comprise part of the melanoma microenvironment. To accomplish this, cells were grown in different in vitro cell culture models and were treated with varying amounts of CAP. Subsequent alterations in viability, proliferation, and phenotype were analyzed via flow cytometry and metabolic alterations by Seahorse Cell Mito Stress Tests. It was found that cells generally exhibited reduced viability and proliferation, stemming from CAP induced G2/M cell cycle arrest and subsequent apoptosis, as well as increased mitochondrial stress following CAP treatment. Overall, sensitivity to CAP treatment was found to be cell type dependent with T cells being the most affected. Interestingly, CAP influenced the polarization of M0 macrophages to a "M0/M2-like" phenotype, and M1 macrophages were found to display a heightened sensitivity to CAP induced mitochondrial stress. CAP also inhibited the growth and killed melanoma cells in 2D and 3D in vitro cell culture models in a dose-dependent manner. Improving our understanding of oxidative stress, mechanisms to manipulate it, and its implications for the tumor microenvironment may help in the discovery of new therapeutic targets.

Systemically Administered TLR7/8 Agonist and Antigen-Conjugated Nanogels Govern Immune Responses against Tumors.

The generation of specific humoral and cellular immune responses plays a pivotal role in the development of effective vaccines against tumors. Especially the presence of antigen-specific, cytotoxic T cells influences the outcome of therapeutic cancer vaccinations. Different strategies, ranging from delivering antigen-encoding mRNAs to peptides or full antigens, are accessible but often suffer from insufficient immunogenicity and require immune-boosting adjuvants as well as carrier platforms to ensure stability and adequate retention. Here, we introduce a pH-responsive nanogel platform as a two-component antitumor vaccine that is safe for intravenous application and elicits robust immune responses in vitro and in vivo. The underlying chemical design allows for straightforward covalent attachment of a model antigen (ovalbumin) and an immune adjuvant (imidazoquinoline-type TLR7/8 agonist) onto the same nanocarrier system. In addition to eliciting antigen-specific T and B cell responses that outperform mixtures of individual components, our two-component nanovaccine leads in prophylactic and therapeutic studies to an antigen-specific growth reduction of different tumors expressing ovalbumin intracellularly or on their surface. Regarding the versatile opportunities for functionalization, our nanogels are promising for the development of highly customized and potent nanovaccines.

Kaposi's Sarcoma Associated-Herpes Virus (KSHV) Seroprevalence in Pregnant Women in South Africa.

BACKGROUND: Factors previously associated with Kaposi's sarcoma-associated herpesvirus (KSHV) transmission in Africa include sexual, familial, and proximity to river water. We measured the seroprevalence of KSHV in relation to HIV, syphilis, and demographic factors among pregnant women attending public antenatal clinics in the Gauteng province of South Africa. METHODS: We tested for antibodies to KSHV lytic K8.1 and latent Orf73 antigens in 1740 pregnant women attending antenatal clinics who contributed blood to the "National HIV and Syphilis Sero-Prevalence Survey - South Africa, 2001". Information on HIV and syphilis serology, age, education, residential area, gravidity, and parity was anonymously linked to evaluate risk factors for KSHV seropositivity. Clinics were grouped by municipality regions and their proximity to the two main river catchments defined. RESULTS: KSHV seropositivity (reactive to either lytic K8.1 and latent Orf73) was nearly twice that of HIV (44.6% vs. 23.1%). HIV and syphilis seropositivity was 12.7% and 14.9% in women without KSHV, and 36.1% and 19.9% respectively in those with KSHV. Women who are KSHV seropositive were 4 times more likely to be HIV positive than those who were KSHV seronegative (AOR 4.1 95%CI: 3.4 - 5.7). Although, women with HIV infection were more likely to be syphilis seropositive (AOR 1.8 95%CI: 1.3 - 2.4), no association between KSHV and syphilis seropositivity was observed. Those with higher levels of education had lower levels of KSHV seropositivity compared to those with lower education levels. KSHV seropositivity showed a heterogeneous pattern of prevalence in some localities. CONCLUSIONS: The association between KSHV and HIV seropositivity and a lack of common association with syphilis, suggests that KSHV transmission may involve geographical and cultural factors other than sexual transmission.

Part II: Cancer in Indigenous Africans--causes and control.

Africa has contributed substantial knowledge to the understanding of certain risk factors for cancer, such as the role of several infectious agents (eg, viruses, bacteria, and parasites), aflatoxins, and certain lifestyle factors. Although the relative importance of many lifestyle factors is becoming better understood in developed countries, more work is needed to understand the importance of these factors in different African settings. In view of the substantial genetic diversity in Africa, it would be prudent not to generalize too widely from one place to the next. We argue that risks for several exposures related to certain cancers differ from the patterns seen in developed countries. In this paper, we review the current knowledge of causes of some of the leading cancers in Africa, namely cancers of the cervix, breast, liver, prostate, stomach, bladder, and oesophagus, Kaposi's sarcoma, non-Hodgkin lymphoma, and tobacco-related cancers. There are no comprehensive cancer-control programmes in Africa and provision of radiotherapy, chemotherapy, and palliation is inadequate. Certain cost-effective interventions, such as tobacco control, provision of antiretroviral therapy, and malarial and bilharzial control, can cause substantial decreases in the burden of some of these cancers. Vaccinations against hepatitis B and oncogenic human papilloma viruses can make the biggest difference, but very few countries in Africa can afford these vaccines without substantial subsidization.

Part I: Cancer in Indigenous Africans--burden, distribution, and trends.

Cancer is an under-emphasised issue in Africa, partly because of the overwhelming burden of communicable diseases. However cancer is a common disease in Africa with 650 000 people, of a population of 965 million, diagnosed annually. Furthermore, the lifetime risk in females (between 0 and 64 years) of cancer is about 10%, which is only about 30% lower than the risk in developed countries. In females, the lifetime risk of dying from cancer in Africa is almost double the risk in developed countries. This Review is the first of two papers and focuses on the current knowledge of the distribution and trends of the most common cancers in Africa. The cancers with the highest incidence are cervical, breast, and now HIV-associated Kaposi's sarcoma. The top five cancers in males--Kaposi's sarcoma (constituting 12.9% of all cancers in males) and cancer of the liver (14.8%), prostate (9.5%), bladder (6.1%), and non-Hodgkin lymphoma (5.7%)--and in females--cancer of the cervix (constituting 23.3% of all cancers in females) and breast (19.2%), Kaposi's sarcoma (5.1%), cancer of the liver (5.0%), and non-Hodgkin lymphoma (3.7%)--are discussed in detail. The second paper will focus on the causes and control of cancer in Africa. The cancer burden in Africa is likely to increase as a result of increases in HIV-associated cancers, changes in lifestyles associated with economic development, and the increasing age of the population (despite AIDS). Although the knowledge of cancer in this region is improving, better surveillance of cancer incidence, mortality, and prevalence of risk factors is urgently needed to monitor the development of the cancer epidemic, formulate appropriate cancer-control strategies, and assess the outcomes of these strategies.

The spectrum of human immunodeficiency virus-associated cancers in a South African black population: results from a case-control study, 1995-2004.

The effect of the evolving HIV epidemic on cancer has been sparsely documented in Africa. We report results on the risk of cancer associated with HIV-1 infection using data from an ongoing study. A case-control analysis was used to estimate the relative risk (odds ratio, OR) of cancer types known to be AIDS defining: Kaposi's sarcoma (n = 333), non-Hodgkin lymphoma (NHL, n = 223) and cancers of the cervix (n = 1,586), and 11 cancer types possibly associated with HIV infection: Hodgkin lymphoma (n = 154), cancers of other anogenital organs (n = 157), squamous cell cancer of the skin (SCC, n = 70), oral cavity and pharynx (n = 319), liver (n = 83), stomach (n = 142), leukemia (n = 323), melanoma (n = 53), sarcomas other than Kaposi's (n = 93), myeloma (n = 189) and lung cancer (n = 363). The comparison group comprised 3,717 subjects with all other cancer types and 682 subjects with vascular disease. ORs were adjusted for age, sex (except cervical cancer), year of diagnosis, education and number of sexual partners. Significantly increased risks associated with HIV-1 infection were found for HIV/AIDS associated Kaposi's sarcoma (OR = 47.1, 95% CI = 31.9-69.8), NHL (OR = 5.9, 95% CI = 4.3-8.1) and cancer of the cervix (OR = 1.6, 95% CI = 1.3-2.0); Hodgkin's disease (OR = 1.6, 95% CI = 1.0-2.7), cancers of anogenital organs other than the cervix (OR = 2.2; 95% CI = 1.4-3.3) and SCC (OR = 2.6, 95% CI = 1.4-4.9) were also significantly increased. No significant associations were found between HIV and any of the other cancers examined. Risks for HIV-related cancers are consistent with previous studies in Africa, and are lower when compared to those observed in developed countries.

No evidence of sexual transmission of Kaposi's sarcoma herpes virus in a heterosexual South African population.

BACKGROUND: The transmission of Kaposi's sarcoma herpes virus (KSHV) in men who have sex with men is clearly associated with sexual risk factors, but evidence of heterosexual transmission of KSHV is conflicting. METHODS: Sera were obtained from 2103 South African individuals (862 miners, 95 sex workers, 731 female and 415 male township residents; mean age 33.2 years; +/- 10.1). All sera were tested for antibodies to KSHV lytic K8.1 and latent Orf73, HIV, gonococcus, herpes simplex virus type 2 (HSV-2), syphilis and chlamydia. Information on social, demographic and high-risk sexual behavior was linked to laboratory data, to evaluate risk factors, expressed as odds ratios (95% confidence interval) for KSHV. RESULTS: Overall KSHV and HIV prevalences were 47.5 and 40%, respectively (P = 0.43). The risk of HIV infection was highest in sex workers then female residents and miners, compared with male residents (P < 0.001). HSV-2 infection was highly prevalent (66%) and lower, but still substantial, prevalences (6-8%) were observed for other sexually transmitted infections (STI). No significant difference in KSHV infection was observed among the residential groups (P > 0.05). KSHV was not associated with any of the STI or any measures of sexual behavior (P > 0.05). CONCLUSION: The pattern of HIV and STI in sex workers suggests high rates of high-risk sexual behavior in this population. The lack of association with high-risk sexual behavior, particularly in sex workers, and with any markers of STI strongly suggest that the sexual mode does not play a significant role in KSHV transmission in this South African population.

The relationship between anti-HPV-16 IgG seropositivity and cancer of the cervix, anogenital organs, oral cavity and pharynx, oesophagus and prostate in a black South African population.

BACKGROUND: Human papillomavirus type 16 (HPV-16) infection is an important cause of cervical cancer, other anogenital cancers and, possibly, some oral and pharyngeal cancers. The association of HPV-16 with oesophageal and with prostate cancers has not been firmly established. METHODS: We analysed sera from 3,757 HIV seronegative black South Africans using an anti-HPV IgG enzyme-linked immunosorbent assay (ELISA). The subjects were recruited from 1995 to 2000 as part of an ongoing cancer case control study. Cases were patients with newly diagnosed cancers of the cervix (n = 946), other anogenital organs (n = 80), the oral cavity and pharynx (n = 102), the oesophagus (n = 369) or the prostate (n = 205). The comparison group consisted of 2,055 age and sex-matched patients randomly selected from the same data base, diagnosed at the same hospitals, but with a vascular disease or with a cancer unrelated to HPV infection. Subjects' sera were randomly and blindly allocated onto ELISA plates. Optical density (OD) levels of anti-HPV-16 IgG of > 0.45 and > or = 0.767 were taken to be cut-offs for negative, medium and high antibody levels. RESULTS: After adjustment for potential confounders, cancer types that showed a statistically significant association with increased anti-HPV-16 IgG antibody (Ab) levels were cancer of the cervix (OR for medium Ab levels = 1.6, and for high = 2.4, p < 0.0001), cancers of other anogenital organs (OR for medium or high Ab levels = 2.5, p = 0.002), and cancer of the oesophagus (OR for medium Ab = 1.3, and high Ab levels = 1.6 p = 0.002). Cancers of the oral cavity and pharynx showed a borderline significant association in the unadjusted model (p = 0.05) but after adjustment for confounding the trend in relation to Ab levels was positive but not statistically significant (OR for medium Ab = 1.1, and high Ab = 1.5 p = 0.13). Prostate cancer was not associated with HPV-16 seropositivity (OR for medium Ab level = 1.4, and for high Ab level = 1.3, p = 0.3). CONCLUSION: If there is indeed an association between HPV-16 and oesophageal and possibly also some oral cavity and pharyngeal cancers, then emerging HPV vaccines may also reduce, at least in part, the incidence of these leading cancer types.

Transmission of Kaposi sarcoma-associated herpesvirus between mothers and children in a South African population.

BACKGROUND: To assess whether Kaposi sarcoma-associated herpesvirus (KSHV) with or without HIV coinfection in South African mothers is associated with higher KSHV seropositivity in their children. METHODS: We tested sera from 1287 South African children and 1179 mothers using assays for KSHV lytic K8.1 and latent ORF73 antigens. We computed odds ratios (ORs) and 95% confidence intervals (CIs) to assess associations between KSHV serostatus and risk factors. RESULTS: KSHV seroprevalence was 15.9% (204 of 1287 subjects) in children and 29.7% (350 of 1179 subjects) in mothers. The risk of KSHV seropositivity was significantly higher in children of KSHV-seropositive mothers compared with those of KSHV-seronegative mothers. The HIV status of mothers was marginally associated with an increased risk of KSHV seropositivity in their children (OR = 1.6, 95% CI: 1.0 to 2.6; P = 0.07). KSHV seroprevalence was significantly higher in HIV-infected subjects (P = 0.0005), and HIV-infected subjects had significantly higher lytic and latent KSHV antibody levels than HIV-negative subjects. CONCLUSIONS: The risk of acquisition of KSHV was higher among children of KSHV-seropositive mothers. Although KSHV seroprevalence was significantly higher in children and mothers who were infected with HIV, the HIV status of the mother was only marginally associated with an increased risk of KSHV seropositivity in the child.

Risk factors for high anti-HHV-8 antibody titers (> or =1:51,200) in black, HIV-1 negative South African cancer patients: a case control study.

BACKGROUND: Infection with human herpesvirus 8 (HHV-8), also known as Kaposi's sarcoma-associated herpesvirus (KSHV), is the necessary causal agent in the development of Kaposi's sarcoma (KS). Infection with HIV-1, male gender and older age all increase risk for KS. However, the geographic distribution of HHV-8 and KS both prior to the HIV/AIDS epidemic and with HIV/AIDS suggest the presence of an additional co-factor in the development of KS. METHODS: Between January 1994 and October 1997, we interviewed 2576 black in-patients with cancer in Johannesburg and Soweto, South Africa. Blood was tested for antibodies against HIV-1 and HHV-8 and the study was restricted to 2191 HIV-1 negative patients. Antibodies against the latent nuclear antigen of HHV-8 encoded by orf73 were detected with an indirect immunofluorescence assay. We examined the relationship between high anti-HHV-8 antibody titers (> or =1:51,200) and sociodemographic and behavioral factors using unconditional logistic regression models. Variables that were significant at p = 0.10 were included in multivariate analysis. RESULTS: Of the 2191 HIV-1 negative patients who did not have Kaposi's sarcoma, 854 (39.0%) were positive for antibodies against HHV-8 according to the immunofluorescent assay. Among those seropositive for HHV-8, 530 (62.1%) had low titers (1:200), 227 (26.6%) had medium titers (1:51,200) and 97 (11.4%) had highest titers (1:204,800). Among the 2191 HIV-1 negative patients, the prevalence of high anti-HHV-8 antibody titers (> or =1:51,200) was independently associated with increasing age (p-trend = 0.04), having a marital status of separated or divorced (p = 0.003), using wood, coal or charcoal as fuel for cooking 20 years ago instead of electricity (p = 0.02) and consuming traditional maize beer more than one time a week (p = 0.02; p-trend for increasing consumption = 0.05) although this may be due to chance given the large number of predictors considered in this analysis. CONCLUSIONS: Among HIV-negative subjects, patients with high anti-HHV-8 antibody titers are characterized by older age. Other associations that may be factors in the development of high anti-HHV-8 titers include exposure to poverty or a low socioeconomic status environment and consumption of traditional maize beer. The relationship between these variables and high anti-HHV-8 titers requires further, prospective study.