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1.
bioRxiv ; 2024 Jun 27.
Article in English | MEDLINE | ID: mdl-38948837

ABSTRACT

A single arm trial (NCT007773097) and a double-blind, placebo controlled randomized trial ( NCT02134925 ) were conducted in individuals with a history of advanced colonic adenoma to test the safety and immunogenicity of the MUC1 tumor antigen vaccine and its potential to prevent new adenomas. These were the first two trials of a non-viral cancer vaccine administered in the absence of cancer. The vaccine was safe and strongly immunogenic in 43% (NCT007773097) and 25% ( NCT02134925 ) of participants. The lack of response in a significant number of participants suggested, for the first time, that even in a premalignant setting, the immune system may have already been exposed to some level of suppression previously reported only in cancer. Single-cell RNA-sequencing (scRNA-seq) on banked pre-vaccination peripheral blood mononuclear cells (PBMCs) from 16 immune responders and 16 non-responders identified specific cell types, genes, and pathways of a productive vaccine response. Responders had a significantly higher percentage of CD4+ naive T cells pre-vaccination, but a significantly lower percentage of CD8+ T effector memory (TEM) cells and CD16+ monocytes. Differential gene expression (DGE) and transcription factor inference analysis showed a higher level of expression of T cell activation genes, such as Fos and Jun, in CD4+ naive T cells, and pathway analysis showed enriched signaling activity in responders. Furthermore, Bayesian network analysis suggested that these genes were mechanistically connected to response. Our analyses identified several immune mechanisms and candidate biomarkers to be further validated as predictors of immune responses to a preventative cancer vaccine that could facilitate selection of individuals likely to benefit from a vaccine or be used to improve vaccine responses.

2.
Article in English | MEDLINE | ID: mdl-38864844

ABSTRACT

BACKGROUND: Cancers of ductal origin often express glycoprotein mucin 1 (MUC1), also known as CA15.3, with higher levels leading to poorer prognosis. Conversely, anti-MUC1 antibodies develop in some patients leading to better prognosis. We sought to identify epidemiologic factors associated with CA15.3 antigen or antibody levels. METHODS: Levels of CA15.3 antigen and anti-CA15.3 IgG antibodies were measured in archived sera from 2302 mostly healthy women from the National Health and Nutritional Survey (NHANES); and epidemiologic predictors of their levels were examined using multivariate and correlational analyses. RESULTS: Among racial groups, Black women had the highest level of CA15.3 antigen and lowest levels of antibodies. Increasing BMI and current smoking were associated with low anti-CA15.3 antibody levels. Low CA15.3 antigen levels were seen in oral contraceptive (OC) users and high levels in women who were pregnant or lactating at the time of blood collection, with the latter group also having high antibody levels. Past reproductive events associated with high antigen levels included: later age at menarche, having given birth, and history of endometriosis. Lower antigen levels were seen with increasing duration of OC use. Anti-CA15.3 antibody levels decreased with an increasing estimated number of ovulatory years. CONCLUSION: Key determinants of CA.15.3 antigen or antibody levels include: race, BMI, smoking, later menarche, childbirth, number of ovulatory cycles, and endometriosis. IMPACT: This study supports the premise that known epidemiologic factors affecting risk for or survival after MUC1-expressing cancers may, at least partially, operate through their association with CA15.3 antigen or antibody levels.

3.
medRxiv ; 2024 May 10.
Article in English | MEDLINE | ID: mdl-38766010

ABSTRACT

Self-antigens abnormally expressed on tumors, such as MUC1, have been targeted by therapeutic cancer vaccines. We recently assessed in two clinical trials in a preventative setting whether immunity induced with a MUC1 peptide vaccine could reduce high colon cancer risk in individuals with a history of premalignant colon adenomas. In both trials, there were immune responders and non-responders to the vaccine. Here we used PBMC pre-vaccination and 2 weeks after the first vaccine of responders and non-responders selected from both trials to identify early biomarkers of immune response involved in long-term memory generation and prevention of adenoma recurrence. We performed flow cytometry, phosflow, and differential gene expression analyses on PBMCs collected from MUC1 vaccine responders and non-responders pre-vaccination and two weeks after the first of three vaccine doses. MUC1 vaccine responders had higher frequencies of CD4 cells pre-vaccination, increased expression of CD40L on CD8 and CD4 T-cells, and a greater increase in ICOS expression on CD8 T-cells. Differential gene expression analysis revealed that iCOSL, PI3K AKT MTOR, and B-cell signaling pathways are activated early in response to the MUC1 vaccine. We identified six specific transcripts involved in elevated antigen presentation, B-cell activation, and NF-kB1 activation that were directly linked to finding antibody response at week 12. Finally, a model using these transcripts was able to predict non-responders with accuracy. These findings suggest that individuals who can be predicted to respond to the MUC1 vaccine, and potentially other vaccines, have greater readiness in all immune compartments to present and respond to antigens. Predictive biomarkers of MUC1 vaccine response may lead to more effective vaccines tailored to individuals with high risk for cancer but with varying immune fitness.

4.
J Membr Biol ; 257(1-2): 37-50, 2024 Apr.
Article in English | MEDLINE | ID: mdl-38460011

ABSTRACT

In skeletal muscle, the Ca2+ release flux elicited by a voltage clamp pulse rises to an early peak that inactivates rapidly to a much lower steady level. Using a double pulse protocol the fast inactivation follows an arithmetic rule: if the conditioning depolarization is less than or equal to the test depolarization, then decay (peak minus steady level) in the conditioning release is approximately equal to suppression (unconditioned minus conditioned peak) of the test release. This is due to quantal activation by voltage, analogous to the quantal activation of IP3 receptor channels. Two mechanisms are possible. One is the existence of subsets of channels with different sensitivities to voltage. The other is that the clusters of Ca2+-gated Ryanodine Receptor (RyR) ß in the parajunctional terminal cisternae might constitute the quantal units. These Ca2+-gated channels are activated by the release of Ca2+ through the voltage-gated RyR α channels. If the RyR ß were at the basis of quantal release, it should be modified by strong inhibition of the primary voltage-gated release. This was attained in two ways, by sarcoplasmic reticulum (SR) Ca2+ depletion and by voltage-dependent inactivation. Both procedures reduced global Ca2+ release flux, but SR Ca2+ depletion reduced the single RyR current as well. The effect of both interventions on the quantal properties of Ca2+ release in frog skeletal muscle fibers were studied under voltage clamp. The quantal properties of release were preserved regardless of the inhibitory maneuver applied. These findings put a limit on the role of the Ca2+-activated component of release in generating quantal activation.


Subject(s)
Muscle, Skeletal , Sarcoplasmic Reticulum , Sarcoplasmic Reticulum/metabolism , Muscle, Skeletal/metabolism , Muscle Fibers, Skeletal/metabolism , Ryanodine Receptor Calcium Release Channel/metabolism , Ryanodine Receptor Calcium Release Channel/pharmacology , Calcium Signaling , Calcium/metabolism
5.
J Immunother Cancer ; 12(3)2024 Mar 21.
Article in English | MEDLINE | ID: mdl-38519057

ABSTRACT

Invasive cancers typically evade immune surveillance through profound local and systemic immunosuppression, preventing their elimination or control. Targeting immune interventions to prevent or intercept premalignant lesions, before significant immune dysregulation has occurred, may be a more successful strategy. The field of cancer immune interception and prevention is nascent, and the scientific community has been slow to embrace this potentially most rational approach to reducing the global burden of cancer. This may change due to recent promising advances in cancer immunoprevention including the use of vaccines for the prevention of viral cancers, the use of cancer-associated antigen vaccines in the setting of precancers, and the development of cancer-preventative vaccines for high-risk individuals who are healthy but carry cancer-associated heritable genetic mutations. Furthermore, there is increasing recognition of the importance of cancer prevention and interception by national cancer organizations. The National Cancer Institute (NCI) recently released the National Cancer Plan, which includes cancer prevention among the top priorities of the institute. The NCI's Division of Cancer Prevention has been introducing new funding opportunities for scientists with an interest in the field of cancer prevention: The Cancer Prevention-Interception Targeted Agent Discovery Program and The Cancer Immunoprevention Network. Moreover, the Human Tumor Atlas Network is spearheading the development of a precancer atlas to better understand the biology of pre-invasive changes, including the tissue microenvironment and the underlying genetics that drive carcinogenesis. These data will inform the development of novel immunoprevention/immuno-interception strategies. International cancer foundations have also started recognizing immunoprevention and immune interception with the American Association for Cancer Research, Cancer Research UK and the Society for Immunotherapy of Cancer each implementing programming focused on this area. This review will present recent advances, opportunities, and challenges in the emerging field of cancer immune prevention and immune interception.


Subject(s)
Cancer Vaccines , Neoplasms , Humans , United States , Immunotherapy , Neoplasms/prevention & control , Mutation , Tumor Microenvironment
6.
Bio Protoc ; 13(18): e4814, 2023 Sep 20.
Article in English | MEDLINE | ID: mdl-37753473

ABSTRACT

Device-induced thrombosis remains a major complication of extracorporeal life support (ECLS). To more thoroughly understand how blood components interact with the artificial surfaces of ECLS circuit components, assessment of clot deposition on these surfaces following clinical use is urgently needed. Scanning electron microscopy (SEM), which produces high-resolution images at nanoscale level, allows visualization and characterization of thrombotic deposits on ECLS circuitry. However, methodologies to increase the quantifiability of SEM analysis of ECLS circuit components have yet to be applied clinically. To address these issues, we developed a protocol to quantify clot deposition on ECLS membrane oxygenator gas transfer fiber sheets through digital and SEM imaging techniques. In this study, ECLS membrane oxygenator fiber sheets were obtained, fixed, and imaged after use. Following a standardized process, the percentage of clot deposition on both digital images and SEM images was quantified using ImageJ through blind reviews. The interrater reliability of quantitative analysis among reviewers was evaluated. Although this protocol focused on the analysis of ECLS membrane oxygenators, it is also adaptable to other components of the ECLS circuits such as catheters and tubing. Key features • Quantitative analysis of clot deposition using digital and scanning electron microscopy (SEM) techniques • High-resolution images at nanoscale level • Extracorporeal life support (ECLS) devices • Membrane oxygenators • Blood-contacting surfaces Graphical overview.

7.
Nat Commun ; 14(1): 2463, 2023 05 09.
Article in English | MEDLINE | ID: mdl-37160880

ABSTRACT

Chimeric antigen receptors (CARs) and synthetic Notch (synNotch) receptors are engineered cell-surface receptors that sense a target antigen and respond by activating T cell receptor signaling or a customized gene program, respectively. Here, to expand the targeting capabilities of these receptors, we develop "universal" receptor systems for which receptor specificity can be directed post-translationally via covalent attachment of a co-administered antibody bearing a benzylguanine (BG) motif. A SNAPtag self-labeling enzyme is genetically fused to the receptor and reacts with BG-conjugated antibodies for covalent assembly, programming antigen recognition. We demonstrate that activation of SNAP-CAR and SNAP-synNotch receptors can be successfully targeted by clinically relevant BG-conjugated antibodies, including anti-tumor activity of SNAP-CAR T cells in vivo in a human tumor xenograft mouse model. Finally, we develop a mathematical model to better define the parameters affecting universal receptor signaling. SNAP receptors provide a powerful strategy to post-translationally reprogram the targeting specificity of engineered cells.


Subject(s)
Receptors, Chimeric Antigen , Humans , Animals , Mice , Receptors, Chimeric Antigen/genetics , Antibodies , Disease Models, Animal , Heterografts , Transplantation, Heterologous
8.
Clin Cancer Res ; 29(9): 1678-1688, 2023 05 01.
Article in English | MEDLINE | ID: mdl-36892581

ABSTRACT

PURPOSE: To assess whether MUC1 peptide vaccine produces an immune response and prevents subsequent colon adenoma formation. PATIENTS AND METHODS: Multicenter, double-blind, placebo-controlled randomized trial in individuals age 40 to 70 with diagnosis of an advanced adenoma ≤1 year from randomization. Vaccine was administered at 0, 2, and 10 weeks with a booster injection at week 53. Adenoma recurrence was assessed ≥1 year from randomization. The primary endpoint was vaccine immunogenicity at 12 weeks defined by anti-MUC1 ratio ≥2.0. RESULTS: Fifty-three participants received the MUC1 vaccine and 50 placebo. Thirteen of 52 (25%) MUC1 vaccine recipients had a ≥2-fold increase in MUC1 IgG (range, 2.9-17.3) at week 12 versus 0/50 placebo recipients (one-sided Fisher exact P < 0.0001). Of 13 responders at week 12, 11 (84.6%) responded to a booster injection at week 52 with a ≥2-fold increase in MUC1 IgG measured at week 55. Recurrent adenoma was observed in 31 of 47 (66.0%) in the placebo group versus 27 of 48 (56.3%) in the MUC1 group [adjusted relative risk (aRR), 0.83; 95% confidence interval (CI), 0.60-1.14; P = 0.25]. Adenoma recurrence occurred in 3/11 (27.3%) immune responders at week 12 and week 55 (aRR, 0.41; 95% CI, 0.15-1.11; P = 0.08 compared with placebo). There was no difference in serious adverse events. CONCLUSIONS: An immune response was observed only in vaccine recipients. Adenoma recurrence was not different than placebo, but a 38% absolute reduction in adenoma recurrence compared with placebo was observed in participants who had an immune response at week 12 and with the booster injection.


Subject(s)
Adenoma , Colonic Neoplasms , Colorectal Neoplasms , Adult , Aged , Humans , Middle Aged , Adenoma/prevention & control , Colorectal Neoplasms/prevention & control , Immunoglobulin G , Vaccines, Subunit
10.
Cancer Cell ; 40(6): 559-564, 2022 06 13.
Article in English | MEDLINE | ID: mdl-35700704

ABSTRACT

Given the renewed interest in vaccine development sparked by the COVID-19 pandemic, we are revisiting the current state of vaccine development for cancer prevention and treatment. Experts discuss different vaccine types, their antigens and modes of action, and where we stand on their clinical development, plus the challenges we need to overcome for their broad implementation.


Subject(s)
COVID-19 , Cancer Vaccines , Neoplasms , COVID-19/prevention & control , Cancer Vaccines/therapeutic use , Humans , Neoplasms/prevention & control , Pandemics/prevention & control
11.
J Transl Med ; 20(1): 179, 2022 04 21.
Article in English | MEDLINE | ID: mdl-35449104

ABSTRACT

As part of the 2021 Immunotherapy Bridge virtual congress (December 1-2, Naples, Italy), the Great Debate sessions featured experts who were assigned counter opposing views on four important questions in immunotherapy today. The first topic was whether oncolytic viruses or other specific immunomodulators were the more promising approach for intralesional therapy. The second was whether early surrogate endpoints, such as response rate or progression-free survival, correlate with long-term overall survival was considered. Thirdly, whether vaccines can transform cold into hot tumors was discussed and, finally, broad versus deep analytic profiling approaches to gain insights into immune-oncology development were compared. As with previous Bridge congresses, presenters were invited by the meeting Chairs and positions taken during the debates may not have reflected their respective personal view. In addition, the views summarised in this article are based on available evidence but may reflect personal interpretation of these data, clinical experience and subjective opinion of the speaker.


Subject(s)
Melanoma , Humans , Immunologic Factors , Immunotherapy , Medical Oncology , Melanoma/pathology , Progression-Free Survival
12.
Front Immunol ; 12: 749597, 2021.
Article in English | MEDLINE | ID: mdl-34712237

ABSTRACT

The ability of immune cells to sense changes associated with malignant transformation as early as possible is likely to be important for the successful outcome of cancer immunosurveillance. In this process, the immune system faces a trade-off between elimination of cells harboring premalignant or malignant changes, and autoimmune pathologies. We hypothesized that the immune system has therefore evolved a threshold for the stage of transformation from normal to fully malignant cells that first provides a threat (danger) signal requiring a response. We co-cultured human macrophages with a unique set of genetically related human cell lines that recapitulate successive stages in breast cancer development: MCF10A (immortalized, normal); MCFNeoT (benign hyperplasia); MCFT1 (atypical hyperplasia); MCFCA1 (invasive cancer). Using cytokines-based assays, we found that macrophages were inert towards MCF10A and MCFNeoT but were strongly activated by MCFT1 and MCFCA1 to produce inflammatory cytokines, placing the threshold for recognition between two premalignant stages, the earlier stage MCFNeoT and the more advanced MCFT1. The cytokine activation threshold paralleled the threshold for enhanced phagocytosis. Using proteomic and transcriptomic approaches, we identified surface molecules, some of which are well-known tumor-associated antigens, that were absent or expressed at low levels in MCF10A and MCFNeoT but turned on or over-expressed in MCFT1 and MCFCA1. Adding antibodies specific for two of these molecules, Annexin-A1 and CEACAM1, inhibited macrophage activation, supporting their role as cancer "danger signals" recognized by macrophages.


Subject(s)
Cell Transformation, Neoplastic , Macrophage Activation , Macrophages/immunology , Annexin A1/immunology , Antigens, CD/immunology , Cell Adhesion Molecules/immunology , Cell Line, Tumor , Coculture Techniques , Cytokines/immunology , Humans , Neoplasms/immunology , Phagocytosis
13.
Am J Addict ; 30(5): 445-452, 2021 09.
Article in English | MEDLINE | ID: mdl-34405475

ABSTRACT

BACKGROUND AND OBJECTIVES: The rapid scale-up of telehealth services for substance use disorders (SUDs) during the COVID-19 pandemic presented a unique opportunity to investigate patient experiences with telehealth. This study examined patient perceptions of telehealth in an outpatient SUD treatment program offering individual therapy, group therapy, and medication management. METHODS: Two hundred and seventy adults receiving SUD outpatient treatment were eligible to complete a 23-item online survey distributed by clinicians; 58 patients completed/partially completed the survey. Data were summarized with descriptive statistics. RESULTS: Participants were predominately male, White, and well-educated. The majority (86.2%) were "very satisfied" or "satisfied" with the quality of telehealth care. "Very satisfied" ratings were highest for individual therapy (90%), followed by medication management (75%) and group therapy (58%). Top reasons for liking telehealth included the ability to do it from home (90%) and not needing to spend time commuting (83%). Top reasons for disliking telehealth were not connecting as well with other members in group therapy (28%) and the ability for telehealth to be interrupted at home or work (26%). DISCUSSION AND CONCLUSIONS: Telehealth visits were a satisfactory treatment modality for most respondents receiving outpatient SUD care, especially those engaging in individual therapy. Challenges remain for telehealth group therapy. SCIENTIFIC SIGNIFICANCE: This is the first study examining patients' perceptions of telehealth for outpatient SUD treatment during the COVID-19 pandemic by treatment service type. Importantly, while many participants found telehealth more accessible than in-person treatment, there was variability with respect to the preferred mode of treatment delivery.


Subject(s)
Ambulatory Care , COVID-19 , Outpatients , Pandemics , Patient Satisfaction , Substance-Related Disorders , Telemedicine , Adult , Ambulatory Care/methods , COVID-19/epidemiology , Female , Health Care Surveys , Humans , Male , Outpatients/psychology , Outpatients/statistics & numerical data , Patient Satisfaction/statistics & numerical data , Psychotherapy, Group , Substance-Related Disorders/therapy
14.
Nat Rev Clin Oncol ; 18(9): 591-602, 2021 09.
Article in English | MEDLINE | ID: mdl-33976418

ABSTRACT

Many tumour antigens that do not arise from cancer cell-specific mutations are targets of humoral and cellular immunity despite their expression on non-malignant cells. Thus, in addition to the expected ability to detect mutations and stress-associated shifts in the immunoproteome and immunopeptidome (the sum of MHC class I-bound peptides) unique to malignant cells, the immune system also recognizes antigens expressed in non-malignant cells, which can result in autoimmune reactions against non-malignant cells from the tissue of origin. These autoimmune manifestations include, among others, vitiligo, thyroiditis and paraneoplastic syndromes, concurrent with melanoma, thyroid cancer and non-small-cell lung cancer, respectively. Importantly, despite the undesirable effects of these symptoms, such events can have prognostic value and correlate with favourable disease outcomes, suggesting 'beneficial autoimmunity'. Similarly, the occurrence of dermal and endocrine autoimmune adverse events in patients receiving immune-checkpoint inhibitors can have a positive predictive value for therapeutic outcomes. Neoplasias derived from stem cells deemed 'not essential' for survival (such as melanocytes, thyroid cells and most cells in sex-specific organs) have a particularly good prognosis, perhaps because the host can tolerate autoimmune reactions that destroy tumour cells at some cost to non-malignant tissues. In this Perspective, we discuss examples of spontaneous as well as therapy-induced autoimmunity that correlate with favourable disease outcomes and make a strong case in favour of this 'beneficial autoimmunity' being important not only in patients with advanced-stage disease but also in cancer immunosurveillance.


Subject(s)
Autoimmunity/physiology , Neoplasms/diagnosis , Biomarkers, Tumor/immunology , Biomarkers, Tumor/metabolism , Female , Humans , Immunologic Surveillance/immunology , Male , Neoplasms/immunology , Neoplasms/pathology , Prognosis
15.
J Transl Med ; 19(1): 144, 2021 04 07.
Article in English | MEDLINE | ID: mdl-33827609

ABSTRACT

As part of the 2020 Immunotherapy Bridge virtual congress (December 2nd-3rd, Italy), the Great Debate session featured counterpoint views from leading experts on three clinical questions in immunotherapy today. The first of these was whether antitumoral vaccination is still a treatment option. The second topic debated whether anti-programmed death (PD)-1/PD-ligand (L)1 blockade should be the backbone for immunotherapy combination. Finally, the use of innovative study designs and surrogate endpoints was considered from both an academic and industry perspective. For each topic, two experts presented the argument and counter-argument in support of two different points of view. As with previous Bridge congresses, the debates were assigned by meeting Chairs and positions taken by experts during the debates may not have necessarily reflected their respective personal view. The views summarised in this article are based on available evidence but may reflect personal interpretation of these data, clinical experience and subjective opinion of the speaker.


Subject(s)
Immunotherapy , Italy
16.
J Clin Gastroenterol ; 55(2): 127-133, 2021 02 01.
Article in English | MEDLINE | ID: mdl-32195770

ABSTRACT

BACKGROUND: MUC1-glycoprotein is expressed at low levels and in fully glycosylated form on epithelial cells. Inflammation causes MUC1 overexpression and hypoglycosylation. We hypothesized that overexpression of hypoglycosylated MUC1 would be found in postoperative Crohn's disease (CD) recurrence and could be considered an additional biomarker of recurrence severity. METHODS: We examined archived neo-terminal ileum biopsies from patients with prior ileocecal resection who had postoperative endoscopic assessment of CD recurrence and given a Rutgeerts ileal recurrence score. Consecutive tissue sections were stained using 2 different anti-MUC1 antibodies, HMPV that recognizes all forms of MUC1 and 4H5 that recognizes only inflammation-associated hypoglycosylated MUC1. RESULTS: A total of 71 postoperative CD patients were evaluated. There was significant increase in MUC1 expression of both glycosylated/normal (P<0.0001) and hypoglycosylated/abnormal (P<0.0001) forms in patients with severe endoscopic CD recurrence (i3+i4), ileal score i2, compared with patients in endoscopic remission (i0+i1). Results were similar regardless of anti-TNF-α use. Although MUC1 expression and Rutgeerts scores were in agreement when characterizing the majority of cases, there were a few exceptions where MUC1 expression was characteristic of more severe recurrence than implied by Rutgeerts score. CONCLUSIONS: MUC1 is overexpressed and hypoglycosylated in neo-terminal ileum tissue of patients with postoperative CD recurrence. Increased levels are associated with more severe endoscopic recurrence scores, and this is not influenced by anti-TNF-α use. Discrepancies found between Rutgeerts scores and MUC1 expression suggest that addition of MUC1 as a biomarker of severity of postoperative CD recurrence may improve categorization of recurrence status and consequently treatment decisions.


Subject(s)
Crohn Disease , Mucin-1/genetics , Colon , Colonoscopy , Crohn Disease/surgery , Humans , Mucins , Recurrence , Retrospective Studies , Tumor Necrosis Factor Inhibitors
17.
J Theor Biol ; 504: 110371, 2020 11 07.
Article in English | MEDLINE | ID: mdl-32533961

ABSTRACT

In skeletal muscle, Ca2+ release from the sarcoplasmic reticulum (SR) triggers contraction. In this study we develop a two compartment model to account for the Ca2+ dynamics in frog skeletal muscle fibers. The two compartments in the model correspond to the SR and the cytoplasm, where the myofibrils are placed. We use a detailed model for the several Ca2+ binding proteins in the cytoplasm in line with previous models. As a new feature, Ca2+ binding sites within the SR, attributed to calsequestrin, are modeled based on experimentally obtained properties. The intra SR Ca2+ buffer shows cooperativity, well represented by a Hill equation with parameters that depend on the initial [Ca2+] in the SR ([Ca2+]SR). The number of total sites as well as the [Ca2+]SR of half saturation are reduced as the resting [Ca2+]SR is reduced, on the other hand the Hill number is not changed. The buffer power remained roughly constant. The release process is activated by a voltage dependent mechanism that increases the Ca2+ permeability of the SR. We use the permeability time course and amplitude experimentally obtained during a voltage clamp pulse to drive the simulations. This model successfully reproduces the SR and cytoplasmic transients observed. Additionally, we simulate [Ca2+] SR transients in the case of high concentration of extrinsic Ca2+ buffers added to the cytoplasm to explore what properties of the permeability are necessary to account for the experimentally observed [Ca2+]SR transients. The main novelty of the model, the intra SR Ca2+ buffer, is crucial for reproducing the experimental observations and it would be of use in future theoretical studies of excitation contraction coupling in skeletal muscle.


Subject(s)
Calcium , Sarcoplasmic Reticulum , Calcium/metabolism , Calsequestrin , Muscle Fibers, Skeletal/metabolism , Muscle, Skeletal/metabolism , Sarcoplasmic Reticulum/metabolism
18.
Cancer Immunol Res ; 8(8): 1027-1038, 2020 08.
Article in English | MEDLINE | ID: mdl-32467324

ABSTRACT

Tumor-associated antigens (TAA) are self-molecules abnormally expressed on tumor cells, which elicit humoral and cellular immunity and are targets of immunosurveillance. Immunity to TAAs is found in some healthy individuals with no history of cancer and correlates positively with a history of acute inflammatory and infectious events and cancer risk reduction. This suggests a potential role in cancer immunosurveillance for the immune memory elicited against disease-associated antigens (DAA) expressed on infected and inflamed tissues that are later recognized on tumors as TAAs. To understand probable sources for DAA generation, we investigated in vitro the role of inflammation that accompanies both infection and carcinogenesis. After exposure of normal primary breast epithelial cells to proinflammatory cytokines IL1ß, IL6, and TNFα, or macrophages producing these cytokines, we saw transient overexpression of well-known TAAs, carcinoembryonic antigen and Her-2/neu, and overexpression and hypoglycosylation of MUC1. We documented inflammation-induced changes in the global cellular proteome by 2D difference gel electrophoresis combined with mass spectrometry and identified seven new DAAs. Through gene profiling, we showed that the cytokine treatment activated NF-κB and transcription of the identified DAAs. We tested three in vitro-identified DAAs, Serpin B1, S100A9, and SOD2, and found them overexpressed in premalignant and malignant breast tissues as well as in inflammatory conditions of the colon, stomach, and liver. This new category of TAAs, which are also DAAs, represent a potentially large number of predictable, shared, immunogenic, and safe antigens to use in preventative cancer vaccines and as targets for cancer therapies.


Subject(s)
Antigens, Neoplasm/immunology , Autoantigens/immunology , Cancer Vaccines/immunology , Epithelial Cells/immunology , Neoplasms/immunology , Neoplasms/metabolism , Autoantigens/metabolism , Cancer Vaccines/pharmacology , Cells, Cultured , Epithelial Cells/metabolism , Healthy Volunteers , Humans , Inflammation/immunology , Inflammation/metabolism , Inflammation/pathology , Leukocytes, Mononuclear/immunology , Macrophages/immunology , Macrophages/metabolism , Monitoring, Immunologic/methods , Neoplasms/pathology , Neoplasms/therapy , Proteomics/methods
19.
Mol Carcinog ; 59(7): 852-861, 2020 07.
Article in English | MEDLINE | ID: mdl-32333615

ABSTRACT

The ultimate success of any form of cancer therapy or cancer prevention depends on its ability to engage the power of the immune system to completely eliminate a growing tumor, lower the life-time tumor risk and establish long-term memory to prevent recurrence or future tumors. For that reason, all therapies but especially immunotherapies depend on the immune health (immunocompetence) of each treated individual. Cancer and chronic illnesses, combined with a usually more advanced age of cancer patients or those at risk for cancer are known to severely suppress multiple antitumor functions of the immune system. Understanding the critical mechanisms controlling and mediating immune suppression can lead to additional therapies to alleviate the effects of those mechanisms and improve the outcome of cancer therapy and prevention. We introduce and review here a highly immunosuppressive cell population found in cancer, precancer, and chronic inflammatory diseases, myeloid derived suppressor cells (MDSC). First described in the setting of advanced cancer, their presence and immunosuppressive activity has been seen more recently in early premalignant lesions and in chronic inflammatory diseases leading to cancer. We describe the detrimental effects of their presence on cancer immunotherapy, immunosurveillance and immunoprevention and review early attempts to develop drugs to eliminate them or reduce their negative impact.


Subject(s)
Myeloid-Derived Suppressor Cells/immunology , Neoplasms/immunology , Animals , Humans , Immunosuppression Therapy/methods , Immunotherapy/methods , Inflammation/immunology , Tumor Microenvironment/immunology
20.
Semin Immunol ; 47: 101394, 2020 02.
Article in English | MEDLINE | ID: mdl-32273212

ABSTRACT

Immune responses to a large number of mutated and non-mutated tumor antigens have been studied in an attempt to unravel the highly complex immune response to cancer. Better understanding of both the effectors and the targets of successful immunosurveillance can inform various immunotherapeutic approaches, which can strengthen or replace natural immunosurveillance that a tumor has managed to escape. In this review we highlight targets of antibodies generated in the context of diseases other than cancer, such as asthma, allergies, autoimmune disorders, inflammation and infections, where the antibody presence correlates either with an increased or a reduced lifetime risk of cancer. We focus on their target antigens, self-molecules abnormally expressed on diseased cells or cross-reactive with exogenous antigens and found on cancer cells as tumor associated antigens (TAA). We refer to them as disease-associated antigens (DAA). We review 4 distinct categories of antibodies according to their target DAA, their origin and their reported impact on cancer risk: natural antibodies, autoantibodies, long-term memory antibodies and allergy-associated antibodies. Increased understanding and focus on their specific targets could enable a more rational choice of antigens for both therapeutic and preventative cancer vaccines and other more effective and less toxic cancer immunotherapies.


Subject(s)
Antibodies/genetics , Antibodies/immunology , Antigens, Neoplasm/immunology , Immunotherapy , Neoplasms/immunology , Neoplasms/therapy , Autoantibodies/immunology , Disease Management , Disease Susceptibility , Humans , Hypersensitivity/immunology , Immunoglobulin E/immunology , Immunotherapy/adverse effects , Immunotherapy/methods , Microbiota , Molecular Mimicry , Neoplasms/pathology , Neoplasms/prevention & control , Precancerous Conditions , T-Lymphocytes/immunology , T-Lymphocytes/metabolism
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