Broad-spectrum Delta-BA.2 tandem-fused heterodimer mRNA vaccine delivered by lipopolyplex

Since the beginning of the coronavirus disease 2019 (COVID-19) pandemic, severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), the causative agent of COVID-19, continues to mutate and generates new variants with increasingly severe immune escape, urging the upgrade of COVID-19 vaccines. Here, based on a similar dimeric RBD design as our previous ZF2001 vaccine, we developed a novel broad-spectrum COVID-19 mRNA vaccine, SWIM516, with chimeric Delta-BA.2 RBD dimer delivered by lipopolyplex (LPP). Unlike the popular lipid nanoparticle (LNP), this LPP-delivered mRNA expresses only in the injection site, which avoids potential toxicity to the liver. We demonstrated the broad-spectrum humoral and cellular immunogenicity of this vaccine to Delta and Omicron sub-variants in naïve mice and as booster shots. When challenged with Delta or Omicron live virus, vaccinated human angiotensin-converting enzyme (hACE2) transgenic mice and rhesus macaques were both protected, displaying significantly reduced viral loads and markedly relieved pathological damages. We believe the SWIM516 vaccine qualifies as a candidate for the next-generation broad-spectrum COVID-19 vaccine.

An inoculation site-retained mRNA vaccine induces robust immune responses against SARS-CoV-2 variants

mRNA-based vaccines and therapeutic agents hold great promise in prevention and treatment of human diseases, yet high percentage of systemic adverse effect in clinic remains a big safety concern. One major potential cause is a high level of leakage of the locally inoculated mRNA vaccine nanoparticles into circulation. We have screened and optimized a core-shell structured lipopolyplex (LPP) formulation for mRNA with a tissue-retention property. Upon intramuscular inoculation, the mRNA-encapsulated LPP nanoparticles were preferentially taken up by the phagocytic antigen-presentation cells, and potently promoted dendritic cell maturation. We applied the new formulation to prepare a prophylactic vaccine for SARS-CoV-2, and observed potent humoral and cellular immune responses from the vaccine in both murine models and non-human primates. More importantly, the vaccine demonstrated a benign safety profile in non-human primates, with limited side effects after repeated treatment with high dosages of LPP/mRNA. Taken together, the inoculation site-retained vaccine formulation serves as a promising vehicle for mRNA vaccines and therapeutic agents.

Osteoporosis is associated with depression among older adults: a nationwide population-based study in the USA from 2005 to 2020

OBJECTIVES

The global prevalence of osteoporosis is rising, yet it is unclear whether people with osteoporosis have a higher risk of depression than those without osteoporosis.

STUDY DESIGN

A cross-sectional study.

METHODS

We used nationally representative data from the US National Health and Nutrition Examination Survey (NHANES) in 2005-2006, 2007-2008, 2009-2010, 2013-2014, and 2017-2020. The diagnosis of osteoporosis was based on the bone mineral density of the femoral neck measured by dual-energy X-ray absorptiometry. Depression was assessed by the Patient Health Questionnaire-9 (PHQ-9), with a score ≥5 as depressive symptoms and a score ≥10 as probable depression. We used logistic regression models to evaluate the association between osteoporosis and depressive symptoms and probable depression.

RESULTS

We included 11,603 adults (aged 50 years and older, 52.3% male) and observed 5.2% of them had osteoporosis. 31.9% of these osteoporotic people had depressive symptoms, and 10.0% had probable depression. Compared to participants without osteoporosis, those with osteoporosis were 1.73 times more likely to experience depressive symptoms (odds ratio [OR] = 1.73, 95% confidence interval [CI] 1.20-2.50) and 1.91 times more likely to experience probable depression (OR = 1.91, 95% CI 1.02-3.59), after adjusting for sex, age, race/ethnicity, education, marital status, family income, body mass index, smoking, physical activity, and alcohol abuse. Moderate-to-vigorous activities mediated the associations between osteoporosis and depression and depressive symptoms.

CONCLUSIONS

Osteoporosis is an independent risk factor for depression. This study highlights the need to evaluate the mental well-being of patients with osteoporosis in clinical and primary health care.

Safety, immunogenicity, and efficacy of a modified COVID-19 mRNA vaccine, SW-BIC-213, in healthy people aged 18 years and above: a phase 3 double-blinded, randomized, parallel controlled clinical trial in Lao PDR (Laos)

Background

The mRNA vaccine has demonstrated significant effectiveness in protecting against SARS-CoV-2 during the pandemic, including against severe forms of the disease caused by emerging variants. In this study, we examined safety, immunogenicity, and relative efficacy of a heterologous booster of the lipopolyplex (LPP)-based mRNA vaccine (SW-BIC-213) versus a homologous booster of an inactivated vaccine (BBIBP) in Laos.

Methods

In this phase 3 clinical trial, which was randomized, parallel controlled and double-blinded, healthy adults aged 18 years and above were recruited from the Southern Savannakhet Provincial Hospital and Champhone District Hospital. The primary outcomes were safety and immunogenicity, with efficacy as an exploratory endpoint. Participants who were fully immunized with a two-dose inactivated vaccine for more than 6 months were assigned equally to either the SW-BIC-213 group (25 μg) or BBIBP group. The primary safety endpoint was to describe the safety profile of all participants in each group up to 6 months post-booster immunization. The primary immunogenic outcome was to demonstrate the superiority of the neutralizing antibody response, in terms of geometric mean titers (GMTs) of SW-BIC-213, compared with BBIBP 28 days after the booster dose. The exploratory efficacy endpoint aimed to assess the relative efficacy of SW-BIC-213 compared to BBIBP against virologically confirmed symptomatic COVID-19 over a 6-month period. The trial was registered with ClinicalTrials.gov (NCT05580159).

Findings

Between October 10, 2022, and January 13, 2023, 1200 participants were assigned to SW-BIC-213 group and 1203 participants in the BBIBP group. All adverse reactions observed during the study were tolerable, transient, and resolved spontaneously. Solicited local reactions were the main adverse reactions in both the SW-BIC-213 group (43.8%) and BBIBP group (14.8%) (p < 0.001). Heterologous boosting with SW-BIC-213 induced higher live virus neutralizing antibodies to SARS-CoV-2 wildtype and BA.5 strains with GMTs reaching 750.1 and 192.9 than homologous boosting with BBIBP with GMTs of 131.5 (p < 0.001) and 47.5 (p < 0.001) on day 29. The statistical findings revealed that, following a period of 14-day to 6-month after booster vaccination, the SW-BIC-213 group exhibited a relative vaccine efficacy (VE) of 70.1% (95% CI: 34.2-86.4) against symptomatic COVID-19 when compared to the BBIBP group.

Interpretation

A heterologous booster with the COVID-19 mRNA vaccine SW-BIC-213 manifests a favorable safety profile and proves highly immunogenic and efficacious in preventing symptomatic COVID-19 in individuals who have previously received two doses of inactivated vaccine.

Funding

Shanghai Strategic Emerging Industries Development Special Fund, Biomedical Technology Support Special Project of Shanghai "Science and Technology Innovation Action Plan", Shanghai Municipal Science and Technology Commission.

A single immunization with core-shell structured lipopolyplex mRNA vaccine against rabies induces potent humoral immunity in mice and dogs

The persistence and clinical consequences of rabies virus (RABV) infection have prompted global efforts to develop a safe and effective vaccines against rabies. mRNA vaccines represent a promising option against emerging and re-emerging infectious diseases, gaining particular interest since the outbreak of COVID-19. Herein, we report the development of a highly efficacious rabies mRNA vaccine composed of sequence-modified mRNA encoding RABV glycoprotein (RABV-G) packaged in core-shell structured lipopolyplex (LPP) nanoparticles, named LPP-mRNA-G. The bilayer structure of LPP improves protection and delivery of RABV-G mRNA and allows gradual release of mRNA molecules as the polymer degrades. The unique core-shell structured nanoparticle of LPP-mRNA-G facilitates vaccine uptake and demonstrates a desirable biodistribution pattern with low liver targeting upon intramuscular immunization. Single administration of low-dose LPP-mRNA-G in mice elicited potent humoral immune response and provided complete protection against intracerebral challenge with lethal RABV. Similarly, single immunization of low-dose LPP-mRNA-G induced high levels of virus-neutralizing antibody titers in dogs. Collectively, our data demonstrate the potential of LPP-mRNA-G as a promising next-generation rabies vaccine used in human and companion animals.

A New Treatment Planning Method for Efficient Proton ARC Therapy with Direct Minimization of Number of Energy Jumps

PURPOSE/OBJECTIVE(S)

The optimization of energy layer distributions is crucial for efficient proton ARC therapy: on one hand, a sufficient number of energy layers is needed to ensure the plan quality; on the other hand, an excess number of energy jumps can substantially slow down the treatment delivery. This work will develop a new treatment plan optimization method with direct minimization of number of energy jumps (NEJ), which will be shown to outperform state-of-the-art methods in both plan quality and delivery efficiency.

MATERIALS/METHODS

The proposed method jointly optimizes the plan quality and minimizes the NEJ. To minimize NEJ, (1) the proton spots x is summed per energy layer to form the energy vector y; (2) y is binarized via sigmoid transform into y1; (3) y1 is multiplied with a predefined energy order vector via dot product into y2; (4) y2 is filtered through the finite-differencing kernel into y3 in order to identify NEJ; (5) only the NEJ of y3 is penalized, while x is optimized for plan quality. The solution algorithm to this new method is based on iterative convex relaxation.

RESULTS

The new method is validated in comparison with state-of-the-art methods called energy sequencing (ES) method and energy matrix (EM) method. In terms of delivery efficiency, the new method had fewer NEJ, less energy switching time, and generally less total delivery time. In terms of plan quality, the new method had smaller optimization objective values, lower normal tissue dose, and generally better target coverage. A head-and-neck case is provided in the table with the following dosimetric parameters: planning objective value F; conformity index CI; homogeneity index HI; mean dose of larynx DOAR; mean body dose Dbody; the unit of dose is Gy.

CONCLUSION

We have developed a new treatment plan optimization method with direct minimization of NEJ, and demonstrated that this new method outperformed state-of-the-art methods (ES and EM) in both plan quality and delivery efficiency.

Retraction: Radio-photothermal therapy mediated by a single compartment nanoplatform depletes tumor initiating cells and reduces lung metastasis in the orthotopic 4T1 breast tumor model

Retraction of 'Radio-photothermal therapy mediated by a single compartment nanoplatform depletes tumor initiating cells and reduces lung metastasis in the orthotopic 4T1 breast tumor model' by Min Zhou et al., Nanoscale, 2015, 7, 19438-19447, https://doi.org/10.1039/C5NR04587H.

Algorithm for optimized mRNA design improves stability and immunogenicity

Messenger RNA (mRNA) vaccines are being used to combat the spread of COVID-19 (refs. 1-3), but they still exhibit critical limitations caused by mRNA instability and degradation, which are major obstacles for the storage, distribution and efficacy of the vaccine products4. Increasing secondary structure lengthens mRNA half-life, which, together with optimal codons, improves protein expression5. Therefore, a principled mRNA design algorithm must optimize both structural stability and codon usage. However, owing to synonymous codons, the mRNA design space is prohibitively large-for example, there are around 2.4 × 10632 candidate mRNA sequences for the SARS-CoV-2 spike protein. This poses insurmountable computational challenges. Here we provide a simple and unexpected solution using the classical concept of lattice parsing in computational linguistics, where finding the optimal mRNA sequence is analogous to identifying the most likely sentence among similar-sounding alternatives6. Our algorithm LinearDesign finds an optimal mRNA design for the spike protein in just 11 minutes, and can concurrently optimize stability and codon usage. LinearDesign substantially improves mRNA half-life and protein expression, and profoundly increases antibody titre by up to 128 times in mice compared to the codon-optimization benchmark on mRNA vaccines for COVID-19 and varicella-zoster virus. This result reveals the great potential of principled mRNA design and enables the exploration of previously unreachable but highly stable and efficient designs. Our work is a timely tool for vaccines and other mRNA-based medicines encoding therapeutic proteins such as monoclonal antibodies and anti-cancer drugs7,8.

[Distribution characteristics of plasma renin concentration in patients with aldosterone-producing adenoma]

Objective: To analyze the distribution characteristics of plasma renin concentration (PRC) in patients with aldosterone-producing adenoma (APA) and its impact on diagnosis. Methods: In this retrospective case series, clinical data from 200 patients with APA (80 men and 120 women; mean age 45.6 years) in the First Affiliated Hospital of Chongqing Medical University from November 2013 to January 2022 were evaluated. PRC was determined by automated chemiluminescence immunoassay. The distribution characteristics of PRC were analyzed, and 8.2 mU/L was used as the low renin cutoff to evaluate whether renin was suppressed. Results: The median PRC was 1.6 mU/L (range, 0.4-41.5 mU/L). There were 116 patients with APA with PRC of ≤2 mU/L, 41 patients with 2<PRC≤4 mU/L. PRC was not suppressed (PRC>8.2 mU/L) in 8.0% (16/200) of the patients with APA. And PRC was not suppressed in 2.5% (5/200) of the patients with APA, resulting in a primary aldosteronism negative screening outcome. Conclusions: Although most patients with APA have low PRC, there are a small number (8%) of patients whose PRC has not been fully suppressed, which can lead to missed diagnoses during primary aldosteronism screening. While primary aldosteronism is highly suspected, further investigations are required to determine the diagnosis, even if PRC is not fully suppressed at screening.

[Establishment and validation of a nomogram-based predictive model for idiopathic aldosteronism]

Objective: To establish and validate a nomogram-based predictive model for idiopathic hyperaldosteronism (IHA). Methods: This cross-sectional study was conducted with the collected clinical and biochemical data of patients with primary aldosteronism (PA) including 249 patients with unilateral primary aldosteronism (UPA) and 107 patients with IHA, who were treated at the Department of Endocrinology of the First Affiliated Hospital of Chongqing Medical University from November 2013 to November 2022. Plasma aldosterone concentration (PAC) and plasma renin concentration (PRC) were measured by chemiluminescence. Stepwise regression analysis was applied to select the key predictors of IHA, and a nomogram-based scoring model was developed. The model was validated in another external independent cohort of patients with PA including 62 patients with UPA and 43 patients with IHA, who were diagnosed at the Department of Endocrinology, First Affiliated Hospital of Zhengzhou University. An independent-sample t test, Mann-Whitney U test, and χ² test were used for statistical analysis. Results: In the training cohort, in comparison with the UPA group, the IHA group showed a higher serum potassium level [M(Q₁, Q₃), 3.4 (3.1, 3.8) mmol/L vs. 2.7 (2.1, 3.1) mmol/L] and higher PRC [4.0 (2.1, 8.2) mU/L vs. 1.5 (0.6, 3.4) mU/L] and a lower PAC post-saline infusion test (SIT) [305 (222, 416) pmol/L vs. 720 (443, 1 136) pmol/L] and a lower rate of unilateral adrenal nodules [33.6% (36/107) vs. 81.1% (202/249)]; the intergroup differences in these measurements were statistically significant (all P<0.001). Serum potassium level, PRC, PAC post-SIT, and the rate of unilateral adrenal nodules showed similar performance in the IHA group in the validation cohort. After stepwise regression analysis for all significant variables in the training cohort, a scoring model based on a nomogram was constructed, and the predictive parameters included the rate of unilateral adrenal nodules, serum potassium concentration, PAC post-SIT, and PRC in the standing position. When the total score was ≥14, the model showed a sensitivity of 0.65 and specificity of 0.90 in the training cohort and a sensitivity of 0.56 and specificity of 1.00 in the validation cohort. Conclusion: The nomogram was used to successfully develop a model for prediction of IHA that could facilitate selection of patients with IHA who required medication directly.

Diagnostic investigation of Mycoplasma hyorhinis as a potential pathogen associated with neurological clinical signs and central nervous system lesions in pigs

Mycoplasma hyorhinis (M. hyorhinis) is a commensal of the upper respiratory tract in swine with the typical clinical presentations of arthritis and polyserositis in postweaning pigs. However, it has also been associated with conjunctivitis and otitis media, and recently has been isolated from meningeal swabs and/or cerebrospinal fluid of piglets with neurological signs. The objective of this study is to evaluate the role of M. hyorhinis as a potential pathogen associated with neurological clinical signs and central nervous system lesions in pigs. The presence of M. hyorhinis was evaluated in a clinical outbreak and a six-year retrospective study by qPCR detection, bacteriological culture, in situ hybridization (RNAscope®), and phylogenetic analysis and with immunohistochemistry characterization of the inflammatory response associated with its infection. M. hyorhinis was confirmed by bacteriological culture and within central nervous system lesions by in situ hybridization on animals with neurological signs during the clinical outbreak. The isolates from the brain had close genetic similarities from those previously reported and isolated from eye, lung, or fibrin. Nevertheless, the retrospective study confirmed by qPCR the presence of M. hyorhinis in 9.9% of cases reported with neurological clinical signs and histological lesions of encephalitis or meningoencephalitis of unknown etiology. M. hyorhinis mRNA was confirmed within cerebrum, cerebellum, and choroid plexus lesions by in situ hybridization (RNAscope®) with a positive rate of 72.7%. Here we present strong evidence that M. hyorhinis should be included as a differential etiology in pigs with neurological signs and central nervous system inflammatory lesions.

[Identification and verification of α-11 giardin-interacting protein]

OBJECTIVE

To identify and verify the interacting protein of α-11 giardin, so as provide the experimental evidence for studies on the α-11 giardin function.

METHODS

The yeast two-hybrid cDNA library of the Giardia lambia C2 strain and the bait plasmid of α-11 giardin were constructed. All proteins interacting with α-11 giardin were screened using the yeast two-hybrid system. α-11 giardin and all screened potential interacting protein genes were constructed into pBiFc-Vc-155 and pBiFc-Vn-173 plasmids, and co-transfected into the breast cancer cell line MDA-MB-231. The interactions between α-11 giardin and interacting proteins were verified using bimolecular fluorescence complementation (BiFC).

RESULTS

The yeast two-hybrid G. lambia cDNA library which was quantified at 2.715 × 10⁷ colony-forming units (CFU) and the bait plasmid containing α-11 giardin gene without an autoactivation activity were constructed. Following two-round positive screening with the yeast two-hybrid system, two potential proteins interacting with α-11 giardin were screened, including eukaryotic translation initiation factor 5A (EIF5A), calmodulin-dependent protein kinase (CAMKL) and nicotinamide adenine dinucleotide phosphate-specific glutamate dehydrogenase (NADP-GDH), hypothetical protein 1 (GL50803_95880), hypothetical protein 2 (GL50803_87261) and a protein from Giardia canis virus. The α-11 giardin and EIF5A genes were transfected into the pBiFc-Vc-155 and pBiFc-Vn-173 plasmids using BiFC, and the recombinant plasmids pBiFc-Vc-155-α-11 and pBiFc-Vn-173-EIF5A were co-tranfected into MDA-MB-231 cells, which displayed green fluorescence under a microscope, indicating the interaction between α-11 giardin and EIF5A protein in cells.

CONCLUSIONS

The yeast two-hybrid cDNA library of the G. lambia C2 strain has been successfully constructed, and six potential protein interacting with α-11 giardin have been identified, including EIF5A that interacts with α-11 giardin in cells.

Safety and immunogenicity of a modified COVID-19 mRNA vaccine, SW-BIC-213, as a heterologous booster in healthy adults: an open-labeled, two-centered and multi-arm randomised, phase 1 trial

BACKGROUND

We assessed the safety and immunogenicity of a core-shell structured lipopolyplex (LPP) based COVID-19 mRNA vaccine, SW-BIC-213, as a heterologous booster in healthy adults.

METHODS

We conducted an open-labeled, two-centered, and three-arm randomised phase 1 trial. Healthy adults, who had completed a two-dose of inactivated COVID-19 vaccine for more than six months, were enrolled and randomized to receive a booster dose of COVILO (inactivated vaccine) (n = 20) or SW-BIC-213-25μg (n = 20), or SW-BIC-213-45μg (n = 20). The primary study endpoint was adverse events within 30 days post-boosting. The secondary endpoint was the titers of binding antibodies and neutralizing antibodies against the wild-type (WT) of SARS-CoV-2 as well as variants of concern in serum. The exploratory endpoint was the cellular immune responses. This trial was registered with http://www.chictr.org.cn (ChiCTR2200060355).

FINDINGS

Between Jun 6 and Jun 22, 2022, 60 participants were enrolled and randomized to receive a booster dose of SW-BIC-213 (25 μg, n = 20, or 45 μg, n = 20) or COVILO (n = 20). The baseline demographic characteristics of the participants at enrollment were similar among the treatment groups. For the primary outcome, injection site pain and fever were more common in the SW-BIC-213 groups (25 μg and 45 μg). Grade 3 fever was reported in 25% (5/20) of participants in the SW-BIC-213-45μg group but was resolved within 48 h after onset. No fatal events or adverse events leading to study discontinuation were observed. For secondary and exploratory outcomes, SW-BIC-213 elicited higher and longer humoral and cellular immune responses than that in the COVILO group.

INTERPRETATION

SW-BIC-213, a core-shell structured lipopolyplex (LPP) based mRNA vaccine, was safe, tolerable, and immunogenic as a heterologous booster in healthy Chinese adults.

FUNDING

Shanghai Municipal Government, the Science and Technology and Economic Commission of Shanghai Pudong New Area, and mRNA Innovation and Translation Center of Shanghai.

Abstract 2006: A novel macromolecular platinum drug with potent efficacy to overcome cross-resistance in cancer therapy

Background: Small molecular platinum (Pt)-based drugs such as cisplatin, carboplatin, and oxaliplatin have achieved great success in clinic over 40 years in cancer therapy. However, lack of tumor specificity leads to severe side effects. In addition, cancer cells frequently develop resistance to treatment through overexpressing cell surface multi-drug resistant proteins (MDRs). Therefore, it is desirable to develop novel Pt-based drugs with excellent anti-cancer efficacy and a minimal toxicity profile, as well as the capability to overcome drug resistance. We have previously demonstrated that poly(amino acid)-conjugated drugs can reduce toxicity and improve pharmacokinetics of chemotherapeutics and also overcome drug resistance by bypassing MDRs. Here we would like to apply this strategy on Pt drug development.

Method: To address this question, we synthesized a L-aspartic acid-chelated Pt moieties (Asp-Pt), and then conjugated it to poly(L-glutamic acid/L-aspartic acid) to generate a polymeric-Pt macromolecule, namely carrier-platin. We next applied this drug on cancer cell lines including the therapeutic-resistant cancer cells in vitro, and tumor bearing murine models in vivo to evaluate its efficacy and toxicity.

Result: We first tested the cytotoxicity of carrier-platin and compared with a current first-line chemotherapeutic oxaliplatin on colorectal cancer cell CT26 in vitro. Surprisingly, we found that carrier-platin effectively killed the CT26 cancer cells with hours while oxaliplatin slowly induced cell death after days. Importantly, carrier-platin was well-tolerated by non-cancerous cells. Furthermore, carrier-platin killed cancer cells that resistant to current chemotherapeutics in clinic, including cisplatin, oxaliplatin, doxorubicin and docetaxel, as effective as their parental cells. Next, we found that carrier-platin showed prolonged circulation time and high tumor accumulation compared with Pt-equivalent dosage of oxaliplatin. Treatment with 8 mg Pt/kg oxaliplatin caused severe body weight loss and intolerable hematotoxicity in mice, but even higher dose of carrier-platin (12 mg Pt/kg) can be tolerated by mice with stable body weight and did not induce any clinical symptoms. Finally, we revealed that carrier-platin potently inhibited mouse colorectal (CT26) and human ovarian (A2780) tumor growth over Pt-equivalent dosage of oxaliplatin. More importantly, carrier-platin was almost as effective on the cisplatin-resistant A2780 tumors (A2780-Cis) as on the parental A2780 tumors in vivo.

Conclusion: We developed a novel macromolecular drug carrier-platin that overcome shortages of current small molecular Pt drugs. It displayed a satisfactory toxicity profile accompanied with excellent anti-tumor efficacy in vivo. Moreover, carrier-platin overcomes the cross-resistance problem of cancer cells to current chemotherapeutic drugs.

Citation Format: Yongbin Liu, Dongfang Yu, Junhua Mai, Ping-Ying Pan, Shu-Hsia Chen, Haifa Shen. A novel macromolecular platinum drug with potent efficacy to overcome cross-resistance in cancer therapy [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2023; Part 1 (Regular and Invited Abstracts); 2023 Apr 14-19; Orlando, FL. Philadelphia (PA): AACR; Cancer Res 2023;83(7_Suppl):Abstract nr 2006.

Abstract 6799: A porous silicon particle based particulate anti-cancer vaccine for immunotherapy

Background: Anti-cancer vaccine is a widely-studied strategy that activates innate and adaptive host immunity via its adjuvant components and tumor antigens against cancer. Unfortunately, its response rate in clinical trials was not promising. On the vaccine part, sufficient stimulation of strong and long-lasting local and systemic immunity and efficient promotion of intratumoral infiltration of cytotoxic T lymphocytes are among the critical issues determining the therapeutic efficacy of cancer vaccines in addition to the innate features of tumor. Our project aims to develop a porous silicon particle based particulate vaccine against cancer, and investigate the therapeutic mechanism and combinational effects with current first-line strategies.

Method: We first screened the combinations of ligands of Toll-like receptors (TLRs) expressing on antigen presenting cells (APCs) and selected the most powerful combo for immune stimulation. We then loaded the identified adjuvants in addition to antigen peptides to produce vaccine particles. Stimulation and licensing of APCs were tested in vitro, and its therapeutic efficacies were evaluated on multiple orthotopic and systemic metastasis cancer murine models of breast and colon cancers. Furthermore, we investigated the vaccine’s synergistic effects and impacts on tumor microenviroment (TME) with an immunogenic chemotherapeutic oxaliplatin on a CT26 colon cancer model.

Result: According to the adjuvant screening assays, we identified a capable combination of CpG1826 (CpG) and 2’3’-cGAMP (cGAMP), which extensively stimulated the activation, maturation and type-I interferon secretion of APCs. A µGCVax formulation composed by these two adjuvants and antigen peptides was then applied on primary and metastatic HER2+ breast cancer TUBO bearing mice. µGCVax potently promoted the activation and lymph node migration of CD8+ and CD103+ dendritic cells in vivo. Distal metastatic tumor nodules in all different tissues vanished after two vaccinations. Functional cure of cancer and extension of animal survival were achieved. Moreover, oxaliplatin treatment on colon cancer caused immunogenic cell death and generated an immune favorable TME in a subcutaneous CT26 colon cancer model. The combination of µGCVax with the oxaliplatin effectively blocked the progression of large tumor mass. We finally revealed that the reprogramming of TME and the promotion of efficacy were mostly achieved from diminishing myeloid-derived suppressor cells (MDSCs) in tumor.

Conclusion: µGCVax is an effective and board-spectrum formulation for cancer immunotherapy. It effectively induces APC activation and licensing, and stimulates the innate and adaptive immunity against multiple cancers. The combination with oxaliplatin further promotes the therapeutic efficacy of µGCVax by decreasing tumor MDSCs.

Citation Format: Junhua Mai, Yongbin Liu, Dongfang Yu, Haifa Shen. A porous silicon particle based particulate anti-cancer vaccine for immunotherapy. [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2023; Part 1 (Regular and Invited Abstracts); 2023 Apr 14-19; Orlando, FL. Philadelphia (PA): AACR; Cancer Res 2023;83(7_Suppl):Abstract nr 6799.

A107 VISCERAL ADIPOSE TISSUE VOLUME DIFFERENTIATES BETWEEN FIBROSTENOTIC AND INFLAMMATORY CROHN’S DISEASE

Background

Creeping fat, a form of visceral adipose tissue (VAT) that wraps the intestinal wall, influences the formation of Crohn’s disease (CD) strictures. The degree of fat wrapping from intestinal stricture resections is correlated with the extent of chronic inflammation, fibrosis, stricture formation, and response to biologic therapy. VAT and subcutaneous adipose tissue (SAT) ratios from CTE (computed tomography) scans are elevated in CD strictures. However, the definition of strictures in these studies has been poorly defined and not included current well-recognized criteria: 1) bowel wall thickness (BWT), 2) narrowed luminal diameter, and 3) pre-stenotic dilation. (PSD).

Purpose

The objective of this pilot study was to assess the relationship of 2D and 3D VAT:SAT ratios with CT stricture parameters in patients with terminal ileal (TI) CD strictures.

Method

2D VAT:SAT ratios from CT’s of CD patients with TI strictures defined as increased BWT, narrowed luminal diameter (< 50% relative to normal adjacent distended loop), and PSD greater than the stricture diameter were retrospectively obtained from a database and chart review. CT’s from fibrostenotic CD patients were sex and BMI matched to patients with only TI inflammatory behaviour. Patient demographics, medication, smoking, and surgical history were also obtained. Analyses were adjusted for age, sex, and BMI covariates. Unpaired t-tests and multi-variable logistic regression analyses were conducted.

Result(s)

Twenty-eight patients with stricturing CD had a significantly greater mean VAT:SAT volume ratio than 29 non-stricturing CD (41.5 cm³ vs 34.2 cm³, p=0.03). Thirty-six percent (10/28) of CD stricture patients had prior ileocolic resection with a mean disease duration of 13.5 years (range 0-48). The median ileal BWT (7.0 mm, range 4.0-13.0 mm) for the stricturing group was significantly greater than those with inflammatory behaviour (BWT 2.0 mm, p<0.0001). The median luminal diameter and PSD for the stricture group was 2.0 mm (range 0 - 14.0 mm), and 3.0 cm (range 1.0 - 7.3 cm), respectively.

Image

Conclusion(s)

Fibrostenotic TI CD patients have increased VAT:SAT ratios in comparison to those with only inflammatory behaviour. These pilot VAT:SAT results provide an initial foundation for further studies to assess its predictive role in responsiveness of medical or surgical therapies in stricturing CD.

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Disclosure of Interest

None Declared

Meta-analysis of InterTan, PFNA and PFNA-II internal fixation for the treatment of unstable intertrochanteric fractures in elderly individuals

Elderly individuals are often affected by osteoporosis and have poor stability after fracture reduction. Moreover, there is still controversy regarding the clinical effects of the treatment for unstable intertrochanteric fractures in the elderly. The Cochrane, Embase, PubMed, and other databases were searched, and a meta-analysis of the literature on the treatment of unstable intertrochanteric fractures of the elderly with InterTan, PFNA, and PFNA-II was conducted. Seven studies were screened, with a total of 1236 patients. Our meta-analysis results show that InterTan is not significantly different from PFNA in terms of operation and fluoroscopy times, but it takes longer than PFNA-II. In terms of postoperative screw cut, pain, femoral shaft fracture, and secondary operations, InterTan is superior to PFNA and PFNA-II. Conversely, in terms of intraoperative blood loss, hospital stay, and postoperative Harris score, there is no significant difference between InterTan and PFNA and PFNA-II. Compared to PFNA and PFNA-II, InterTan internal fixation has advantages in the treatment of unstable intertrochanteric fractures in elderly individuals in terms of screw cutting, femoral shaft fractures, and secondary operations. However, InterTan operation and fluoroscopy times take longer than PFNA and PFNA-II.

Exploration of 68Ga-labelled prostate-specific membrane antigen-11 PET/CT parameters for identifying PBRM1 status in primary clear cell renal cell carcinoma

AIM

To investigate the predictive value of ⁶⁸Ga-labelled prostate-specific membrane antigen-11 (⁶⁸Ga-PSMA-11) integrated positron-emission tomography (PET)/computed tomography (CT) in PBRM1-deficient clear cell renal cell carcinoma (ccRCC).

MATERIALS AND METHODS

A total of 41 patients with ccRCC, were enrolled retrospectively and underwent ⁶⁸Ga-PSMA-11 PET/CT preoperatively. Radiological parameters, including CT attenuation value and maximum standard uptake value (SUVmax), were derived. Immunohistochemical and multiple immunofluorescences staining were performed to evaluate the PBRM1 status and immune response. The predictive value of imaging factors was analysed using a receiver operator characteristic curve analysis. Univariate and multivariate logistic regression analyses were used to investigate the relationship between clinical and radiological variables and PBRM1 status.

RESULTS

A total of 41 patients were included in this study, with 14 patients having PBRM1-deficient status. The tumour diameter on imaging and SUVmax differed significantly in patients with different PBRM1 expression statuses and no difference in CT attenuation was identified. Univariate and multivariate logistic regression analyses showed SUVmax was an obvious predictor for identification of PBRM1-deficient tumours. In addition, PBRM1-deficient tumours tended to be accompanied by greater cytotoxic T-cell infiltration, although most of them were in an exhausted state.

CONCLUSIONS

⁶⁸Ga-PSMA-11 PET/CT could be used to discriminate invasive PBRM1-deficient ccRCC.

[Comparison between transoral radiofrequency coblation surgery and open partial laryngectomy for the treatment of supraglottic laryngeal carcinoma]

Objective: To explore the feasibility and efficacy of radiofrequency coblation assisted transoral surgery for the treatment of supraglottic laryngeal carcinoma by comparing with concurrent patients treated with conventional transcervical approach. To clarify the advantages of different surgical methods and to summarize the experience of supraglottic carcinoma radiofrequency ablation. Methods: Forty-six patients with supraglottic laryngeal carcinoma treated in department of otorhinolaryngology head and neck surgery, Peking University First Hospital from March 2014 to January 2021 were analyzed retrospectively. Among them(43 males, 3 females, aged from 45 to 79 years old), 23 patients were treated with radiofrequency coblation and 23 patients with partial laryngectomy with conventional transcervical approach. The operation time, intra-operative blood loss volume, recovery time, inpatient total medical cost and follow-up information of the two groups were analyzed. SPSS 26.0 software was used for statistical analysis. Results: There were no significant differences in age, gender, TNM staging,tumor staging and postoperative radiotherapy between the two groups (all P>0.05).The operation time, intra-operative blood loss volume, recovery time, inpatient total medical cost of the RFC-TOS group were110.0(60.0,150.0)min,5.0(5.0,30.0)ml,3.0(2.0,5.0)days,6.0(4.0,14.0)days and 26 100.7(16 145.5,47 044.4)yuan. The data of conventional transcervical approach group were 205.0(156.5,272.3)min, 150.0(50,200) ml, 18.0(16.3,22.8)days and 56520.1(440 992.5,67 109.9)yuan, (Z=-4.03, -4.94, -4.97, -4.98 and -4.13;all P<0.001).The 5-year local control rate, disease-specific survival rate and overall survival rate of the two groups were 86.96%,95.65%,91.30% and 86.96%,91.30%,73.90% renspectively, which had no significant difference between the two groups(all P>0.05). Conclusions: Compared with conventional transcervical surgeries, RFC-TOS could be a reliable new surgical option for organ-function preservation strategy in the treatment of supraglottic laryngeal carcinoma.The RFC is a suitable new technique and deserving more multi-center clinical trials for its clinical promotion.

An mRNA vaccine elicits STING-dependent antitumor immune responses

Lipid-formulated RNA vaccines have been widely used for disease prevention and treatment, yet their mechanism of action and individual components contributing to such actions remain to be delineated. Here, we show that a therapeutic cancer vaccine composed of a protamine/mRNA core and a lipid shell is highly potent in promoting cytotoxic CD8⁺ T cell responses and mediating anti-tumor immunity. Mechanistically, both the mRNA core and lipid shell are needed to fully stimulate the expression of type I interferons and inflammatory cytokines in dendritic cells. Stimulation of interferon-β expression is exclusively dependent on STING, and antitumor activity from the mRNA vaccine is significantly compromised in mice with a defective Sting gene. Thus, the mRNA vaccine elicits STING-dependent antitumor immunity.

A modified porous silicon microparticle potentiates protective systemic and mucosal immunity for SARS-CoV-2 subunit vaccine

Development of optimal SARS-CoV-2 vaccines to induce potent, long-lasting immunity and provide cross-reactive protection against emerging variants remains a high priority. Here, we report that a modified porous silicon microparticle (mPSM) adjuvant to SARS-CoV-2 receptor-binding domain (RBD) vaccine activated dendritic cells and generated more potent and durable systemic humoral and type 1 helper T (Th) cell- mediated immune responses than alum-formulated RBD following parenteral vaccination, and protected mice from SARS-CoV-2 and Beta variant challenge. Notably, mPSM facilitated the uptake of SARS-CoV-2 RBD antigens by nasal and airway epithelial cells. Parenteral and intranasal prime and boost vaccinations with mPSM-RBD elicited stronger lung resident T and B cells and IgA responses compared to parenteral vaccination alone, which led to markedly diminished viral loads and inflammation in the lung following SARS-CoV-2 Delta variant challenge. Overall, our results suggest that mPSM is effective adjuvant for SARS-CoV-2 subunit vaccine in both systemic and mucosal vaccinations.

TCR-engineered iNKT cells induce robust antitumor response by dual targeting cancer and suppressive myeloid cells

Adoptive immunotherapy with T cells engineered with tumor-specific T cell receptors (TCRs) holds promise for cancer treatment. However, suppressive cues generated in the tumor microenvironment (TME) can hinder the efficacy of these therapies, prompting the search for strategies to overcome these detrimental conditions and improve cellular therapeutic approaches. CD1d-restricted invariant natural killer T (iNKT) cells actively participate in tumor immunosurveillance by restricting suppressive myeloid populations in the TME. Here, we showed that harnessing iNKT cells with a second TCR specific for a tumor-associated peptide generated bispecific effectors for CD1d- and major histocompatibility complex (MHC)-restricted antigens in vitro. Upon in vivo transfer, TCR-engineered iNKT (TCR-iNKT) cells showed the highest efficacy in restraining the progression of multiple tumors that expressed the cognate antigen compared with nontransduced iNKT cells or CD8+ T cells engineered with the same TCR. TCR-iNKT cells achieved robust cancer control by simultaneously modulating intratumoral suppressive myeloid populations and killing malignant cells. This dual antitumor function was further enhanced when the iNKT cell agonist α-galactosyl ceramide (α-GalCer) was administered as a therapeutic booster through a platform that ensured controlled delivery at the tumor site, named multistage vector (MSV). These preclinical results support the combination of tumor-redirected TCR-iNKT cells and local α-GalCer boosting as a potential therapy for patients with cancer.

[Interference of P2X4 receptor expression in tumor-associated macrophages suppresses migration and invasion of glioma cells]

OBJECTIVE

To investigate the effect of interference of P2X4 receptor expression in tumor-associated macrophages (TAMs) on invasion and migration of glioma cells.

METHODS

C57BL/6 mouse models bearing gliomas in the caudate nucleus were examined for glioma pathology with HE staining and expressions of Iba-1 and P2X4 receptor with immunofluorescence assay. RAW264.7 cells were induced into TAMs using conditioned medium from GL261 cells, and the changes in mRNA expressions of macrophage polarization-related markers and the mRNA and protein expressions of P2X4 receptor were detected with RT-qPCR and Western blotting. The effect of siRNA-mediated P2X4 interference on IL-1β and IL-18 mRNA and protein expressions in the TAMs was detected with RT-qPCR and Western blotting. GL261 cells were cultured in the conditioned medium from the transfected TAMs, and the invasion and migration abilities of the cells were assessed with Transwell invasion and migration experiment.

RESULTS

The glioma tissues from the tumor-bearing mice showed a significantly greater number of Iba-1-positive cells, where an obviously increased P2X4 receptor expression was detected (P=0.001), than the brain tissues of the control mice (P < 0.001). The M2 macrophage markers (Arg-1 and IL-10) and M1 macrophage markers (iNOS and TNF-α) were both significantly up-regulated in the TAMs derived from RAW264.7 cells (all P < 0.01), but the up-regulation of the M2 macrophage markers was more prominent; the expression levels of P2X4 receptor protein and mRNA were both increased in the TAMs (P < 0.05). Interference of P2X4 receptor expression significantly lowered the mRNA(P < 0.01)and protein (P < 0.01, P < 0.05)expression levels of IL-1β and IL-18 in the TAMs and obviously inhibited the ability of the TAMs to promote invasion and migration of the glioma cells (P < 0.05).

CONCLUSION

Interference of P2X4 receptor in the TAMs suppresses the migration and invasion of glioma cells possibly by lowering the expressions of IL-1β and IL-18.

[Application of three-dimensional visualization technique in laparoscopic D3 radical resection of right colon cancer]

OBJECTIVE

To explore the clinical value of three-dimensional (3D) visualization technique in laparoscopic D3 radical resection of right colon cancer.

METHODS

We retrospectively analyzed the clinical data of 73 patients with right colon cancer undergoing laparoscopic D3 radical operation in our hospital between May, 2019 and March, 2021. Among these patients, 41 underwent enhanced CT examination with 3D visualization reconstruction to guide the actual operation, and 32 underwent enhanced CT examination only before the operation (control group). In 3D visualization group, we examined the coincidence rate between the 3D visualization model and the findings in surgical exploration of the anatomy and variations of the main blood vessels, supplying vessels of the tumor, and the tumor location, and the coincidence rate between the actual surgical plan for D3 radical resection of right colon cancer and the plan formulated based on the 3D model. The operative time, estimated blood loss, unexpected injury of blood vessels, number of harvested lymph nodes, mean time of the first flatus, complications, postoperative hospital stay and postoperative drainage volume were compared between the two groups.

RESULTS

The operative time was significantly shorter in 3D visualization group than in the control group (P < 0.05). The volume of blood loss, proportion of unexpected injury of blood vessel, the number of harvested lymph nodes, time of the first flatus, proportion of complications, postoperative hospital stay and postoperative drainage volume did not differ significantly between the two groups (P > 0.05). In the 3D visualization group, the 3D visualization model clearly displayed the shape and direction of the colon, the location of the tumor, the anatomy and variation of the main blood vessels and the blood vessels supplying the cancer, and showed a coincidence rate of 100% with the findings by surgical exploration. The surgical plan for D3 radical resection of right colon cancer was formulated based on the 3D model also showed a coincidence rate of 100% with the actual surgical plan.

CONCLUSION

The 3D visualization reconstruction technique allows clear visualization the supplying arteries of the tumor and their variations to improve the efficiency, safety and accuracy of laparoscopic D3 radical resection of right colon cancer.

Identification of an Aptamer With Binding Specificity to Tumor-Homing Myeloid-Derived Suppressor Cells

Myeloid-derived suppressor cells (MDSCs) play a critical role in tumor growth and metastasis. Since they constantly infiltrate into the tumor tissue, these cells are considered as an ideal carrier for tumor-targeted drug delivery. We recently identified a DNA-based thioaptamer (T1) with tumor accumulating activity, demonstrated its potential on tumor targeting and drug delivery. In the current study, we have carried out structure-activity relationship analysis to further optimize the aptamer. In the process, we have identified a sequence-modified aptamer (M1) that shows an enhanced binding affinity to MDSCs over the parental T1 aptamer. In addition, M1 can penetrate into the tumor tissue more effectively by hitchhiking on MDSCs. Taken together, we have identified a new reagent for enhanced tumor-targeted drug delivery.

[Comparison of early outcome between one-stage hybrid technique and frozen elephant thunk technique in the treatment of Stanford A aortic dissection involving the arch]

Objective: To analyze the early outcome of one-stage hybrid technique in the treatment of Stanford type-A aortic dissection involving the arch and compare its therapeutic efficacy with the classical frozen elephant trunk technique (FET). Methods: A total of 106 patients with Stanford type-A aortic dissection involving the arch in Department of Cardiac and Vascular Surgery, 1st Affiliated Hospital of Soochow University from October 2015 to October 2019 was collected. All patients in this group were treated with one-stage hybrid technique (modified arch debranching technique) without deep hypothermia circulation. Meanwhile, 30 patients with Stanford type A dissection involving the arch who underwent FET from January 2014 to September 2015 were collected. The therapeutic effects of the two surgical methods were analyzed and compared. Results: The age [M (Q₁, Q₃)] of 106 patients in hybrid group was 49.0 (40.0, 55.0) years, including 89 males and 17 females. The age [M(Q₁, Q₃)] of 30 patients in FET group was 49.5 (41.5, 65.3) years, including 24 males and 6 females. The time [M(Q₁, Q₃)] of using ventilator in hybrid group was 56.0 (38.0, 72.0) h, which was shorter than 127.0 (92.0, 145.0) h in FET group (P<0.001). The incidence of cerebral infarction in hybrid group was 2.8% (3 cases), which was lower than 13.3% (4 cases) in FET group (P=0.042); the incidence of postoperative renal insufficiency in hybrid group was 7.5% (8 cases), which was lower than 23.3% (7 cases) in FET group (P=0.023); the ICU time [M (Q₁, Q₃)] in hybrid group was 8.0 (6.0, 10.0) d, which was shorter than 14.0 (8.3, 24.0) d in FET group (P<0.001). Conclusion: Compared with FET, one-stage hybrid technology is safer and more effective in the treatment of Stanford type A aortic dissection involving the arch. Its short-term therapeutic efficacy appears good.

MiR-524 inhibits cell proliferation and induces cell apoptosis in thyroid cancer via targeting SPAG9

The article "MiR-524 inhibits cell proliferation and induces cell apoptosis in thyroid cancer via targeting SPAG9", by Z. Zhen, F. Dong, H. Shen, Q.-G. Wang, L. Yang, J. Hu, published in Eur Rev Med Pharmacol Sci 2018; 22 (12): 3812-3818-DOI: 10.26355/eurrev_201806_15265-PMID: 29949157, has been retracted by the authors due to some unrepeated data in their current research. The Publisher apologizes for any inconvenience this may cause. https://www.europeanreview.org/article/15265.

Rad51 Silencing with siRNA Delivered by Porous Silicon-Based Microparticle Enhances the Anti-Cancer Effect of Doxorubicin in Triple-Negative Breast Cancer

Due to its high heterogeneity and aggressiveness, cytotoxic chemotherapy is still a mainstay treatment for triple negative breast cancer. Unfortunately, the above mentioned has not significantly ameliorated TNBC patients and induces drug resistance. Exploring the mechanisms underlying the chemotherapy sensitivity of TNBC and developing novel sensitization strategies are promising approaches for improving the prognosis of patients. Rad51, a key regulator of DNA damage response pathway, repairs DNA damage caused by genotoxic agents through "homologous recombination repair." Therefore, Rad51 inhibition may increase TNBC cell sensitivity to anticancer agents. Based on these findings, we first designed Rad51 siRNA to inhibit the Rad51 protein expression in vitro and evaluated the sensitivity of TNBC cells to doxorubicin. Subsequently, we constructed discoidal porous silicon microparticles (pSi) and encapsulated discoidal 1,2-dioleoyl-sn-glycero-3-phosphocholine (DOPC) liposomes/siRad51 (PS-DOPC/siRad51) to explore the synergistic antitumor effects of siRad51 and doxorubicin on two mouse models of TNBC in vivo. Our in vitro studies indicated that siRad51 enhanced the efficacy of DOX chemotherapy and significantly suppressed TNBC cell proliferation and metastasis. This effect was related to apoptosis induction and epithelial to mesenchymal transition (EMT) inhibition. siRad51 altered the expression of apoptosis- and EMT-related proteins. In orthotopic and lung metastasis xenograft models, the administration of PS-DOPC/siRad51 in combination with DOX significantly alleviated the primary tumor burden and lung metastasis, respectively. Our current studies present an efficient strategy to surmount chemotherapy resistance in TNBC through microvector delivery of siRad51.

A modified porous silicon microparticle promotes mucosal delivery of SARS-CoV-2 antigen and induction of potent and durable systemic and mucosal T helper 1 skewed protective immunity

Development of optimal SARS-CoV-2 vaccines to induce potent, long-lasting immunity and provide cross-reactive protection against emerging variants remains a high priority. Here, we report that a modified porous silicon microparticle (mPSM)-adjuvanted SARS-CoV-2 receptor-binding domain (RBD) vaccine activated dendritic cells and generated more potent and durable SARS-CoV-2-specific systemic humoral and type 1 helper T (Th) cell-mediated immune responses than alum-formulated RBD following parenteral vaccination, and protected mice from SARS-CoV-2 and Beta variant infection. mPSM facilitated the uptake of SARS-CoV-2 RBD antigens by nasal and airway epithelial cells. Parenteral and intranasal prime and boost vaccinations with mPSM-RBD elicited potent systemic and lung resident memory T and B cells and SARS-CoV-2 specific IgA responses, and markedly diminished viral loads and inflammation in the lung following SARS-CoV-2 Delta variant infection. Our results suggest that mPSM can serve as potent adjuvant for SARS-CoV-2 subunit vaccine which is effective for systemic and mucosal vaccination.

A heparan-sulfate-bearing syndecan-1 glycoform is a distinct surface marker for intra-tumoral myeloid-derived suppressor cells

Myeloid-derived suppressor cells (MDSCs) infiltrate cancer tissue, promote tumor growth, and are associated with resistance to cancer therapies. However, there is no practical approach available to distinguish MDSCs from mature counterparts inside tumors. Here, we show that a recently isolated thioaptamer probe (T1) binds to MDSC subsets in colorectal and pancreatic tumors with high specificity. Whole transcriptome and functional analysis revealed that T1-binding cells contain polymorphonuclear (PMN)-MDSCs characterized by several immunosuppression pathways, ROS production, and T cell suppression activity, whereas T1-non-binding PMNs were mature and nonsuppressive. We identified syndecan-1 as the T1-interacting protein on MDSCs and chronic myelogenous leukemia K562 cell line. Heparan sulfate chains were essential in T1-binding. Inside tumors PMN-MDSCs expressed heparan sulfate biogenesis enzymes at higher levels. Tumor-cell-derived soluble factor(s) enhanced MDSCs' affinity for T1. Overall, we uncovered heparan-sulfate-dependent MDSC modulation in the tumor microenvironment and identified T1 as tool preferentially targeting tumor-promoting myeloid cell subsets.

The Sympathetic Nervous System Modulates Cancer Vaccine Activity through Monocyte-Derived Cells

The sympathetic nervous system (SNS) is an important regulator of immune cell function during homeostasis and states of inflammation. Recently, the SNS has been found to bolster tumor growth and impair the development of antitumor immunity. However, it is unclear whether the SNS can modulate APC function. Here, we investigated the effects of SNS signaling in murine monocyte-derived macrophages (moMФ) and dendritic cells (DCs) and further combined the nonspecific β-blocker propranolol with a peptide cancer vaccine for the treatment of melanoma in mice. We report that norepinephrine treatment dramatically altered moMФ cytokine production, whereas DCs were unresponsive to norepinephrine and critically lack β₂-adrenergic receptor expression. In addition, we show that propranolol plus cancer vaccine enhanced peripheral DC maturation, increased the intratumor proportion of effector CD8⁺ T cells, and decreased the presence of intratumor PD-L1⁺ myeloid-derived suppressor cells. Furthermore, this combination dramatically reduced tumor growth compared with vaccination alone. Taken together, these results offer insights into the cell-specific manner by which the SNS regulates the APC immune compartment and provide strong support for the use of propranolol in combination with cancer vaccines to improve patient response rates and survival.

Virus-Mimic mRNA Vaccine for Cancer Treatment

An effective therapeutic cancer vaccine should be empowered with the capacity to overcome the immunosuppressive tumor microenvironment. Here, the authors describe a mRNA virus-mimicking vaccine platform that is comprised of a phospholipid bilayer encapsulated with a protein-nucleotide core consisting of antigen-encoding mRNA molecules, unmethylated CpG oligonucleotides and positively charged proteins. In cell culture, VLVP potently stimulated bone marrow-derived dendritic cells (BMDCs) to express inflammatory cytokines that facilitated dendritic cell (DC) maturation and promoted antigen processing and presentation. In tumor-bearing mice, VLVP treatment stimulated proliferation of antigen-specific CD8+T cells in the lymphatic organs and T cell infiltration into the tumor bed, resulting in potent anti-tumor immunity. Cytometry by time of flight (CyTOF) analysis revealed that VLVP treatment stimulated a 5-fold increase in tumor-associated CD8+DCs and a 4-fold increase in tumorinfiltrated CD8+T cells, with concurrent decreases in tumor-associated bone marrow-derived suppressor cells and arginase 1- expressing suppressive DCs. Finally, CpG oligonucleotide is an essential adjuvant for vaccine activity. Inclusion of CpG not only maximized vaccine activity but also prevented PD-1 expression in T cells, serving the dual roles as a potent adjuvant and a checkpoint blockade agent.

[Trajectories of body mass index Z-score and risk of high blood pressure in late adolescence in Suzhou children]

Objective: To identify age and gender standardized body mass index among children and adolescents and explore their associations with high blood pressure (HBP) in late adolescence. Methods: The current study was based on the Health Promotion Program for Children and Adolescents, school-based surveillance successively conducted from 2012 to 2019 in Suzhou, China. A total of 11 812 children and adolescents aged 16-18 years, who had ≥4 examination records during 2012-2018 and were also involved in a surveillance program in 2019, were included. Latent class growth mixture modeling was used to identify the BMI-Z trajectories in different genders, and multivariate logistic regression was used to analyze the associations between different BMI-Z trajectories and risk of HBP in late adolescence. Results: Six distinct BMI-Z trajectories were determined for both genders:thin, slightly thin,standard, declining, overweight, and obese. Compared with the regular group, the obesity group had 94.0% (OR=1.94, 95%CI: 1.43-2.63) and 107.0% (OR=2.07, 95%CI: 1.33-3.22) increased risk of developing HBP in late adolescence in boys and girls, respectively. However, a neutral association was found between the descending group and HBP in late adolescence. Conclusions: Persistent obesity in children may increase the risk of HBP in their late adolescence. If an obese child restores normal weight before late adolescence, the risk of HBP may reduce.

Intra-couple discordance in preconception syphilis screening for both spouses: a national and population-based survey in China, 2013-2018

OBJECTIVE

The antenatal screening strategy remains inadequate for eliminating congenital syphilis. To further eliminate maternal fetal transmission, preconception syphilis screening is considered an option. In this study, we investigated syphilis seropositivity and intra-couple discordance among married couples planning a pregnancy in China to provide essential baseline evidence for preconception syphilis screening.

DESIGN

Population-based survey.

SETTING

National preconception registered data.

POPULATION

Married Chinese couples planning conception within 6 months between 2013 and 2018.

METHODS

Syphilis was screened using rapid plasma reagin (RPR); infection self-reporting and sociodemographic characteristics were collected through questionnaires and medical records, respectively. r 3.2.2 and arcgis 10.2 were used for statistical analyses and geographic mapping.

MAIN OUTCOME MEASURES

RPR seropositivity.

RESULTS

Among 31 955 041 couples, 29 737 172 (93.06%) had complete RPR results for both spouses; of those, 0.62% (186 100) were seropositive, with dramatic intra-couple discordance, with 0.33% positivity in wives, 0.24% positivity in husbands and 0.05% positivity in both spouses. Across time, both seropositivity and intra-couple discordance remained stable. Seropositivity in different regions varied significantly, with provincial rates ranging geographically from Tibet (0.8%) to Hebei (0.2%) (P < 0.05). Economic level was an independent factor for this regional variation, with seropositivity increasing as gross domestic product income decreased (P < 0.05).

CONCLUSIONS

Intra-couple discordance in seropositivity for syphilis is notable among couples, with a considerable rate of pre-existing syphilis before pregnancy. Thus, screening both spouses during integrated preconception health care is recommended for further eliminating maternal-fetal transmission.

TWEETABLE ABSTRACT

Intra-couple discordance in seropositivity for syphilis is notable among couples, with a considerable rate of pre-existing syphilis before pregnancy. Screening both spouses during integrated preconception health care is recommended to further eliminate maternal-fetal transmission.

The association between the vaginal microenvironment and fecundability: a register-based cohort study among Chinese women

OBJECTIVE

To evaluate the association between the vaginal microenvironment and fecundability among women.

DESIGN

Register-based nationwide cohort study.

SETTING

Chinese National Free Pre-conception Check-up Project from 2015 to 2018.

POPULATION

Our study included a total of 3 388 554 eligible women who were attempting to become pregnant.

METHOD

We assessed the vaginal microenvironment at baseline by considering four indices: vaginal pH, clue cell examination, whiff test and vaginal cleanliness grading. If any of these indicators was abnormal, the vaginal microenvironment was defined as poor. Propensity score matching was used to control for potential confounders and reduce bias. Logistic models were used to estimate the fecundability odds ratios (FORs) after adjustment for covariates.

MAIN OUTCOME MEASURES

Achievement of a pregnancy within 1 year.

RESULTS

Of the total study population, 379 718 women (11.2%) had a poor vaginal microenvironment and their pregnancy rate after 1 year was significantly lower than the group with a normal microenvironment (71.8% versus 76.1%, P < 0.001). After adjusting for potential confounders, the women with a poor vaginal microenvironment were associated with a 9% reduction in fecundability compared with the normal microenvironment group (FOR 0.91, 95% CI 0.90-0.92). The adverse effects of a poor vaginal microenvironment were stronger among multipara (FOR 0.89, 95% CI 0.87-0.90) or women with irregular menstruation (FOR 0.86, 95% CI 0.84-0.89).

CONCLUSION

There was a negative association between a poor vaginal microenvironment and the fecundability of women. These findings highlight the significance of assessing the vaginal microenvironment during pre-pregnancy health examinations.

TWEETABLE ABSTRACT

Women with a poor vaginal microenvironment were associated with a reduction in fecundability.

Abstract 2810: Effect of clone dependent difference in the metastatic tumor microenvironment of 4T1 breast cancer on anti-PDL1 antibody delivery & therapeutic efficacy

Heterogeneities in the response of tumors to immunotherapies have significantly limited clinical benefits. Understanding the specific driving forces behind the heterogeneities will facilitate a better understanding of therapeutic resistance. Research has revealed that tumors in patients and established cancer cell lines are composed of multiple clones. Therefore, we established single cell-derived clonal populations from parental, polyclonal 4T1 murine breast cancer cells. Our goal is to dissect these complexities and decipher mechanisms of tumor heterogeneities. We injected 4T1 parental, clone1, or clone 16 cells into the spleen to create multiple liver metastases. Tumor-bearing mice were treated with anti-PDL1 Ab or isotype control Ab, then the therapeutic effect on tumor size and survival were evaluated. In another set of mice, the window chamber was installed above the liver to image the tumors utilizing intravital microscopy. Also, fluorescently labeled anti-PDL1 Ab or control Ab was injected intravenously (iv) to image the accumulation of Ab into the individual tumor. Anti-PDL1 Ab therapy significantly inhibited clone 16 tumor growth and extended survival of the tumor-bearing mice compared to isotype control Ab. On the other hand, parental and clone 1 tumors did not respond to the anti-PDL1 Ab. Using IVM, we monitored individual tumor response to anti-PLD1 Ab for 7 days and correlated the response with the amount of fluorescently labeled anti-PDL1 Ab delivered to the tumor. The amount of iv injected anti-PDL1 Ab delivery was heterogeneous among the tumors originated from 4T1 parental cells. We found an inverse correlation between the amount of the Ab delivered to the tumor and tumor growth, indicating drug delivery dependent tumor response. Metastases originated from clone 16 cells accumulated more amount of the Ab with most tumors disappeared. While the amount of Ab delivered to clone 1 tumor was significantly lower than parental and clone 16 tumors, none of the clone 1 tumors responded. Thus, limited therapeutic efficacy can be attributed to the insufficient anti-PDL1 Ab delivery to the tumor. Immunohistochemical analysis of resected liver revealed that the expression of PDL1 in clone 16 tumors was significantly higher than parental and clone 1 tumor. On the other hand. The amount of immune cells (CD8 & F4/80) were slightly higher in clone 16 than parental and clone 1 tumors. Finally, we compared the amount of coagulation inside the tumor by imaging fibrinogen, which can reduce therapeutics delivery to tumors. Interestingly, the clone 1 tumor showed significantly more amount of coagulation. Evaluation of heterogeneity in PDL1 expression, tumor coagulation, and the immune microenvironment in the patient's tumor shall be considered for personalizing the therapy.

Citation Format: Yan Ting Liu, Thao Nguyen, Shreya Goel, Megumi Kai, Haifa Shen, Kenji Yokoi. Effect of clone dependent difference in the metastatic tumor microenvironment of 4T1 breast cancer on anti-PDL1 antibody delivery & therapeutic efficacy [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2021; 2021 Apr 10-15 and May 17-21. Philadelphia (PA): AACR; Cancer Res 2021;81(13_Suppl):Abstract nr 2810.