CD8+ T cell/cancer-associated fibroblast ratio stratifies prognostic and predictive responses to immunotherapy across multiple cancer types

BACKGROUND

Cancer-associated fibroblasts (CAFs) within the tumor microenvironment (TME) are critical for immune suppression by restricting immune cell infiltration in the tumor stromal zones from penetrating tumor islands and changing their function status, particularly for CD8+ T cells. However, assessing and quantifying the impact of CAFs on immune cells and investigating how this impact is related to clinical outcomes, especially the efficacy of immunotherapy, remain unclear.

MATERIALS AND METHODS

The TME was characterized using immunohistochemical (IHC) analysis using a large-scale sample size of gene expression profiles. The CD8+ T cell/CAF ratio (CFR) association with survival was investigated in The Cancer Genome Atlas (TCGA) and Gene Expression Omnibus (GEO) lung cancer cohorts. The correlation between CFR and immunotherapeutic efficacy was computed in five independent cohorts. The correlation between CFR and objective response rates (ORRs) following pembrolizumab monotherapy was investigated in 20 solid tumor types. To facilitate clinical translation, the IHC-detected CD8/α-SMA ratio was applied as an immunotherapeutic predictive biomarker in a real-world lung cancer cohort.

RESULTS

Compared with normal tissue, CAFs were enriched in cancer tissue, and the amount of CAFs was overwhelmingly higher than that in other immune cells. CAFs are positively correlated with the extent of immune infiltration. A higher CFR was strongly associated with improved survival in lung cancer, melanoma, and urothelial cancer immunotherapy cohorts. Within most cohorts, there was no clear evidence for an association between CFR and programmed death-ligand 1 (PD-L1) or tumor mutational burden (TMB). Compared with TMB and PD-L1, a higher correlation coefficient was observed between CFR and the ORR following pembrolizumab monotherapy in 20 solid tumor types (Spearman's r = 0.69 vs. 0.44 and 0.21). In a real-world cohort, patients with a high CFR detected by IHC benefited considerably from immunotherapy as compared with those with a low CFR (hazard ratio, 0.37; 95% confidence interval, 0.19-0.75; p < 0.001).

CONCLUSIONS

CFR is a newly found and simple parameter that can be used for identifying patients unlikely to benefit from immunotherapy. Future studies are needed to confirm this finding.

Granzyme B in circulating CD8+ T cells as a biomarker of immunotherapy effectiveness and disability in neuromyelitis optica spectrum disorders

BACKGROUND AND OBJECTIVE

Neuromyelitis optica spectrum disorders (NMOSD) are chronical inflammatory demyelinating diseases of the central nervous system (CNS) and the underlying mechanism remains unclear. Several recent studies have demonstrated that T cells play a pivotal role in the pathogenesis of NMOSD.In this study, we investigated CD8+ T cell phenotypes and levels of the cytotoxic protein granzyme B (GzmB), as well as their potential clinical application in NMOSD.

METHODS

In this study, 90 peripheral blood samples were collected from 59 NMOSD patients with seropositive anti-aquaporin-4 (AQP4) antibodies and 31 sex- and age-matched healthy donors (HDs). Flow cytometry was used to detect circulating levels of GzmB and CD8+ T cell subpopulations, including naïve (TN, CCD7+CD45RA+), central memory (TCM, CCD7+CD45RA-), effector memory (TEM, CCD7-CD45RA-), terminal differentiation effector memory cells (TEMRA, CCD7-CD45RA+) in both groups. The associations between GzmB levels in CD8+T cells and clinical characteristics of NMOSD were evaluated.

RESULTS

NMOSD patients exhibited significantly decreased proportions of CD8+TN cells and increased proportions of highly differentiated CD8+T cells (TEMRA) compared with HDs. In addition, levels of GzmB in CD8+ T cells were markedly higher in NMOSD patients than in HDs. Moreover, we observed that high proportions of GzmB-expressing CD8+ T cells were more common in patients with a poor response to immunotherapies, and showed a good potential to distinguish poor responders from responders (ACU=0.89). Clinical correlation analysis indicated that high levels of GzmB in CD8+ T cells were not only related to severe disability but also significantly associated with increased serum levels of neurofilament light (NFL) and glial fibrillary acidic protein (GFAP). Multivariate linear regression analyses further suggested that GzmB expression in CD8+ T cells was predominantly associated with disability and immunotherapy effectiveness in NMOSD, independent of the sex, age, and disease phase. Transcription factor T-bet in CD8+ T cells were also significantly elevated in NMOSD and were associated with increasing number of circulating CD8+TEMRA cells and GzmB-expressing CD8+T cells.

CONCLUSIONS

Our study support the involvement of GzmB-expressing CD8+ T cells in the inflammatory response in patients with NMOSD and provide a potential biomarker for disease immunotherapy effectiveness and disability progression.

Activation of Complement Components on Circulating Blood Monocytes From COVID-19 Patients

The coronavirus disease-2019 (COVID-19) caused by the SARS-CoV-2 virus may vary from asymptomatic to severe infection with multi-organ failure and death. Increased levels of circulating complement biomarkers have been implicated in COVID-19-related hyperinflammation and coagulopathy. We characterized systemic complement activation at a cellular level in 49-patients with COVID-19. We found increases of the classical complement sentinel C1q and the downstream C3 component on circulating blood monocytes from COVID-19 patients when compared to healthy controls (HCs). Interestingly, the cell surface-bound complement inhibitor CD55 was also upregulated in COVID-19 patient monocytes in comparison with HC cells. Monocyte membrane-bound C1q, C3 and CD55 levels were associated with plasma inflammatory markers such as CRP and serum amyloid A during acute infection. Membrane-bounds C1q and C3 remained elevated even after a short recovery period. These results highlight systemic monocyte-associated complement activation over a broad range of COVID-19 disease severities, with a compensatory upregulation of CD55. Further evaluation of complement and its interaction with myeloid cells at the membrane level could improve understanding of its role in COVID-19 pathogenesis.

Tumor-Microenvironment-Responsive Nanomedicine for Enhanced Cancer Immunotherapy

The past decades have witnessed great progress in cancer immunotherapy, which has profoundly revolutionized oncology, whereas low patient response rates and potential immune-related adverse events remain major clinical challenges. With the advantages of controlled delivery and modular flexibility, cancer nanomedicine has offered opportunities to strengthen antitumor immune responses and to sensitize tumor to immunotherapy. Furthermore, tumor-microenvironment (TME)-responsive nanomedicine has been demonstrated to achieve specific and localized amplification of the immune response in tumor tissue in a safe and effective manner, increasing patient response rates to immunotherapy and reducing the immune-related side effects simultaneously. Here, the recent progress of TME-responsive nanomedicine for cancer immunotherapy is summarized, which responds to the signals in the TME, such as weak acidity, reductive environment, high-level reactive oxygen species, hypoxia, overexpressed enzymes, and high-level adenosine triphosphate. Moreover, the potential to combine nanomedicine-based therapy and immunotherapeutic strategies to overcome each step of the cancer-immunity cycle and to enhance antitumor effects is discussed. Finally, existing challenges and further perspectives in this rising field with the hope for improved development of clinical applications are discussed.

An Inter-Supplementary Biohybrid System Based on Natural Killer Cells for the Combinational Immunotherapy and Virotherapy of Cancer

Oncolytic adenoviruses (Ads) have gained great attention in cancer therapy because they cause direct cytolytic infection and indirectly induce antitumor immunity. However, their efficacy is compromised by host antiviral immune response, poor tumor delivery, and the immunosuppressive tumor microenvironment (TME). Here, a natural killer (NK) cell-mediated Ad delivery system (Ad@NK) is generated by harnessing the merits of the two components for combinational immunotherapy and virotherapy of cancer. In this biohybrid system, NK cells with a tumor-homing tropism act as bioreactors and shelters for the loading, protection, replication, amplification, and release of Ads, thereby leading to a highly efficient systemic tumor-targeted delivery. As feedback, Ad infection offers NK cells an enhanced antitumor immunity by activating type I interferon signaling in a STAT4-granzyme B-dependent manner. Moreover, it is found that the Ad@NK system can relieve immunosuppression in the TME by promoting the maturation of dendritic cells and the polarization of macrophages to M1 phenotype. Both in vitro and in vivo data indicate the excellent antitumor and antimetastatic functions of Ad@NKs by destroying tumor cells, inducing immunogenic cell death, and immunomodulating TME. This work provides a clinical basis for improved oncolytic virotherapy in combination with NK cell therapy based on the inter-supplementary biohybrid system.

Schistosome immunomodulators

Schistosomes are long lived, intravascular parasitic platyhelminths that infect >200 million people globally. The molecular mechanisms used by these blood flukes to dampen host immune responses are described in this review. Adult worms express a collection of host-interactive tegumental ectoenzymes that can cleave host signaling molecules such as the "alarmin" ATP (cleaved by SmATPDase1), the platelet activator ADP (SmATPDase1, SmNPP5), and can convert AMP into the anti-inflammatory mediator adenosine (SmAP). SmAP can additionally cleave the lipid immunomodulator sphingosine-1-phosphate and the proinflammatory anionic polymer, polyP. In addition, the worms release a barrage of proteins (e.g., SmCB1, SjHSP70, cyclophilin A) that can impinge on immune cell function. Parasite eggs also release their own immunoregulatory proteins (e.g., IPSE/α1, omega1, SmCKBP) as do invasive cercariae (e.g., Sm16, Sj16). Some schistosome glycans (e.g., LNFPIII, LNnT) and lipids (e.g., Lyso-PS, LPC), produced by several life stages, likewise affect immune cell responses. The parasites not only produce eicosanoids (e.g., PGE2, PGD2-that can be anti-inflammatory) but can also induce host cells to release these metabolites. Finally, the worms release extracellular vesicles (EVs) containing microRNAs, and these too have been shown to skew host cell metabolism. Thus, schistosomes employ an array of biomolecules-protein, lipid, glycan, nucleic acid, and more, to bend host biochemistry to their liking. Many of the listed molecules have been individually shown capable of inducing aspects of the polarized Th2 response seen following infection (with the generation of regulatory T cells (Tregs), regulatory B cells (Bregs) and anti-inflammatory, alternatively activated (M2) macrophages). Precisely how host cells integrate the impact of these myriad parasite products following natural infection is not known. Several of the schistosome immunomodulators described here are in development as novel therapeutics against autoimmune, inflammatory, and other, nonparasitic, diseases.

Targeting the IGF-Axis Potentiates Immunotherapy for Pancreatic Ductal Adenocarcinoma Liver Metastases by Altering the Immunosuppressive Microenvironment

Pancreatic ductal adenocarcinoma (PDAC) is a highly aggressive malignancy, resistant to chemotherapy and associated with high incidence of liver metastases and poor prognosis. Using murine models of aggressive PDAC, we show here that in mice bearing hepatic metastases, treatment with the IGF-Trap, an inhibitor of type I insulin-like growth factor receptor (IGF-IR) signaling, profoundly altered the local, immunosuppressive tumor microenvironment in the liver, curtailing the recruitment of myeloid-derived suppressor cells, reversing innate immune cell polarization and inhibiting metastatic expansion. Significantly, we found that immunotherapy with anti-PD-1 antibodies also reduced the growth of experimental PDAC liver metastases, and this effect was enhanced when combined with IGF-Trap treatment, resulting in further potentiation of a T-cell response. Our results show that a combinatorial immunotherapy based on dual targeting of the prometastatic immune microenvironment of the liver via IGF blockade, on one hand, and reversing T-cell exhaustion on the other, can provide a significant therapeutic benefit in the management of PDAC metastases.

Harnessing the immune system against cancer: current immunotherapy approaches and therapeutic targets

Cancer immunotherapy is a rapidly evolving concept that has been given the tag "fifth pillar" of cancer therapy while radiation therapy, chemotherapy, surgery and targeted therapy remain the other four pillars. This involves the stimulation of the immune system to control tumor growth and it specifically targets the neoplastic cells rather than the normal cells. Conventional chemotherapy has many limitations which include drug resistance, recurrence of cancer and severe adverse effects. Immunology has made major treatment breakthroughs for several cancers such as colorectal cancer, prostate cancer, breast cancer, lung cancer, liver cancer, kidney cancer, stomach cancer, acute lymphoblastic leukaemia etc. Currently, therapeutic strategies harnessing the immune system involve Checkpoint inhibitors, Chimeric antigen receptor T cells (CAR T cells), Monoclonal antibodies, Cancer vaccines, Cytokines, Radio-immunotherapy and Oncolytic virus therapy. The molecular characterization of several tumor antigens (TA) indicates that these TA can be utilized as promising candidates in cancer immunotherapy strategies. Here in this review, we highlight and summarize the different categories of emerging cancer immunotherapies along with the immunologically recognized tumor antigens involved in the tumor microenvironment.

Beta-Glucans from Fungi: Biological and Health-Promoting Potential in the COVID-19 Pandemic Era

Beta-glucans comprise a group of polysaccharides of natural origin found in bacteria, algae, and plants, e.g., cereal seeds, as well as microfungi and macrofungi (mushrooms), which are characterized by diverse structures and functions. They are known for their metabolic and immunomodulatory properties, including anticancer, antibacterial, and antiviral. Recent reports suggest a potential of beta-glucans in the prevention and treatment of COVID-19. In contrast to β-glucans from other sources, β-glucans from mushrooms are characterized by β-1,3-glucans with short β-1,6-side chains. This structure is recognized by receptors located on the surface of immune cells; thus, mushroom β-glucans have specific immunomodulatory properties and gained BRM (biological response modifier) status. Moreover, mushroom beta-glucans also owe their properties to the formation of triple helix conformation, which is one of the key factors influencing the bioactivity of mushroom beta-glucans. This review summarizes the latest findings on biological and health-promoting potential of mushroom beta-glucans for the treatment of civilization and viral diseases, with particular emphasis on COVID-19.

Ly-6D of Japanese flounder (Paralichthys olivaceus) functions as a complement regulator and promotes host clearance of pathogen

The Lymphocyte antigen-6 (Ly-6) superfamily has been considered to play an important role in the innate immunity of mammals. The functions of Ly-6 proteins are diverse since their low sequence homology. Currently, the function of Ly-6D, a member of Ly-6 family proteins, is completely unknown in teleost. In the present study, we identified and characterized a Ly-6D homologue (named PoLy-6D) from the teleost fish Paralichthys olivaceus and examined its immune function. PoLy-6D possesses a hydrophobic signal peptide, a LU domain including a conserved "LXCXXC" motif in N-terminus and a "CCXXXXCN" motif in C-terminus. Under normal physiological condition, PoLy-6D expression distributes in all the examined tissues, the highest three tissues are successively spleen, head kidney, and blood. When infected by extracellular and intracellular bacterial pathogens and viral pathogen, PoLy-6D expression was induced and the patterns vary with different types of microbial pathogens infection and different immune tissues. In vitro experiment showed recombinant PoLy-6D (rPoLy-6D) inhibited the lysis of rabbit red blood cells by serum and selectively improved bacterial survival in serum. After serum were treated by antibody of rPoLy-6D, bacteriostatic effect of serum was obviously enhanced. These results indicate the importance of PoLy-6D as a complement regulator. rPoLy-6D possessed the binding activity to multiple bacteria but did not exhibit antimicrobial activities. The interaction between rPoLy-6D and bacteria suggests that PoLy-6D is involved in host clearance of pathogens probably by serving as a receptor for pathogens. Overexpression of PoLy-6D in vivo promoted the host defense against invading E. piscicida. These findings add new insights into the regulation mechanism of the complement system in teleost and emphasize the importance of Ly-6D products for the control of pathogen infection.

Green nanotechnology of MGF-AuNPs for immunomodulatory intervention in prostate cancer therapy

Men with castration-resistant prostate cancer (CRPC) face poor prognosis and increased risk of treatment-incurred adverse effects resulting in one of the highest mortalities among patient population globally. Immune cells act as double-edged sword depending on the tumor microenvironment, which leads to increased infiltration of pro-tumor (M2) macrophages. Development of new immunomodulatory therapeutic agents capable of targeting the tumor microenvironment, and hence orchestrating the transformation of pro-tumor M2 macrophages to anti-tumor M1, would substantially improve treatment outcomes of CRPC patients. We report, herein, Mangiferin functionalized gold nanoparticulate agent (MGF-AuNPs) and its immunomodulatory characteristics in treating prostate cancer. We provide evidence of immunomodulatory intervention of MGF-AuNPs in prostate cancers through observations of enhanced levels of anti-tumor cytokines (IL-12 and TNF-α) with concomitant reductions in the levels of pro-tumor cytokines (IL-10 and IL-6). In the MGF-AuNPs treated groups, IL-12 was elevated to ten-fold while TNF-α was elevated to about 50-fold, while IL-10 and IL-6 were reduced by two-fold. Ability of MGF-AuNPs to target splenic macrophages is invoked via targeting of NF-kB signaling pathway. Finally, therapeutic efficacy of MGF-AuNPs, in treating prostate cancer in vivo in tumor bearing mice, is described taking into consideration various immunomodulatory interventions triggered by this green nanotechnology-based nanomedicine agent.

Structural basis for the constitutive activity and immunomodulatory properties of the Epstein-Barr virus-encoded G protein-coupled receptor BILF1

Epstein-Barr virus (EBV) encodes a G protein-coupled receptor (GPCR) termed BILF1 that is essential for EBV-mediated immunosuppression and oncogenesis. BILF1 couples with inhibitory G protein (Gi), the major intracellular signaling effector for human chemokine receptors, and exhibits constitutive signaling activity; the ligand(s) for BILF1 are unknown. We studied the origins of BILF1's constitutive activity through structure determination of BILF1 bound to the inhibitory G protein (Gi) heterotrimer. The 3.2-Å resolution cryo-electron microscopy structure revealed an extracellular loop within BILF1 that blocked the typical chemokine binding site, suggesting ligand-autonomous receptor activation. Rather, amino acid substitutions within BILF1 transmembrane regions at hallmark ligand-activated class A GPCR "microswitches" stabilized a constitutively active BILF1 conformation for Gi coupling in a ligand-independent fashion. Thus, the constitutive activity of BILF1 promotes immunosuppression and virulence independent of ligand availability, with implications for the function of GPCRs encoded by related viruses and for therapeutic targeting of EBV.

Exosome loaded immunomodulatory biomaterials alleviate local immune response in immunocompetent diabetic mice post islet xenotransplantation

Foreign body response (FBR) to biomaterials compromises the function of implants and leads to medical complications. Here, we report a hybrid alginate microcapsule (AlgXO) that attenuated the immune response after implantation, through releasing exosomes derived from human Umbilical Cord Mesenchymal Stem Cells (XOs). Upon release, XOs suppress the local immune microenvironment, where xenotransplantation of rat islets encapsulated in AlgXO led to >170 days euglycemia in immunocompetent mouse model of Type 1 Diabetes. In vitro analyses revealed that XOs suppressed the proliferation of CD3/CD28 activated splenocytes and CD3+ T cells. Comparing suppressive potency of XOs in purified CD3+ T cells versus splenocytes, we found XOs more profoundly suppressed T cells in the splenocytes co-culture, where a heterogenous cell population is present. XOs also suppressed CD3/CD28 activated human peripheral blood mononuclear cells (PBMCs) and reduced their cytokine secretion including IL-2, IL-6, IL-12p70, IL-22, and TNFα. We further demonstrate that XOs mechanism of action is likely mediated via myeloid cells and XOs suppress both murine and human macrophages partly by interfering with NFκB pathway. We propose that through controlled release of XOs, AlgXO provide a promising new platform that could alleviate the local immune response to implantable biomaterials.

Toxoplasma gondii Matrix Antigen 1 Is a Secreted Immunomodulatory Effector

Our studies on novel cyst wall proteins serendipitously led us to the discovery that cyst wall and vacuolar matrix protein MAG1, first identified a quarter of a century ago, functions as a secreted immunomodulatory effector. MAG1 is a dense granular protein that is found in the parasitophorous vacuolar matrix in tachyzoite vacuoles and the cyst wall and matrix in bradyzoite vacuoles. In the current study, we demonstrated that MAG1 is secreted beyond the parasitophorous vacuole into the host cytosol in both tachyzoites and bradyzoites. Secretion of MAG1 gradually decreases as the parasitophorous vacuole matures, but prominent MAG1 puncta are present inside host cells even at 4 and 6 days following infection. During acute murine infection, Δmag1 parasites displayed significantly reduced virulence and dissemination. In the chronic stage of infection, Δmag1 parasites generated almost no brain cysts. To identify the mechanism behind the attenuated pathology seen with Δmag1 parasites, various immune responses were screened in vitro using bone marrow-derived macrophages (BMDM). Infection of BMDM with Δmag1 parasites induced a significant increase in interleukin 1β (IL-1β) secretion, which is a hallmark of inflammasome activation. Heterologous complementation of MAG1 in BMDM cells prevented this Δmag1 parasite-induced IL-1β release, indicating that secreted MAG1 in host cytosol dampens inflammasome activation. Furthermore, knocking out GRA15 (an inducer of IL-1β release) in Δmag1 parasites completely inhibited all IL-1β release by host cells following infection. These data suggest that MAG1 has a role as an immunomodulatory molecule and that by suppressing inflammasome activation, it would favor survival of the parasite and the establishment of latent infection.IMPORTANCEToxoplasma gondii is an Apicomplexan that infects a third of humans, causing encephalitis in AIDS patients and intellectual disabilities in congenitally infected patients. We determined that one of the cyst matrix proteins, MAG1, which had been thought to be an innate structural protein, can be secreted into the host cell and suppress the host immune reaction. This particular immune reaction is initiated by another parasite-secreted protein, GRA15. The intricate balance of inflammasome activation by GRA15 and suppression by MAG1 protects mice from acute death while enabling parasites to disseminate and establish chronic cysts. Our finding contributes to our understanding of how parasites persist in the host and how T. gondii modulates the host immune system.

Tumor and immune reprogramming during immunotherapy in advanced renal cell carcinoma

Immune checkpoint blockade (ICB) results in durable disease control in a subset of patients with advanced renal cell carcinoma (RCC), but mechanisms driving resistance are poorly understood. We characterize the single-cell transcriptomes of cancer and immune cells from metastatic RCC patients before or after ICB exposure. In responders, subsets of cytotoxic T cells express higher levels of co-inhibitory receptors and effector molecules. Macrophages from treated biopsies shift toward pro-inflammatory states in response to an interferon-rich microenvironment but also upregulate immunosuppressive markers. In cancer cells, we identify bifurcation into two subpopulations differing in angiogenic signaling and upregulation of immunosuppressive programs after ICB. Expression signatures for cancer cell subpopulations and immune evasion are associated with PBRM1 mutation and survival in primary and ICB-treated advanced RCC. Our findings demonstrate that ICB remodels the RCC microenvironment and modifies the interplay between cancer and immune cell populations critical for understanding response and resistance to ICB.

Enhancement of anti-inflammatory and immunomodulatory effects of adipose-derived human mesenchymal stem cells by making uniform spheroid on the new nano-patterned plates

Human mesenchymal stem cells (MSCs) are known to have anti-inflammatory and immunomodulatory functions; thus, several MSC products have been applied as cell therapy in clinical trials worldwide. Recent studies have demonstrated that MSC spheroids have superior anti-inflammatory and immunomodulatory functions to a single cell suspension. Current methods to prepare MSC spheroids include hanging drop, concave microwell aggregation, spinner flask, and gravity circulation. However, all these methods have limitations such as low scalability, easy cell clumping, low viability, and irregular size distribution. Here, we present a nano-patterned culture plasticware named PAMcell™ 3D plate to overcome these limitations. Nano-sized silica particles (700 nm) coated with RGD peptide were arrayed into fusiform onto the PLGA film. This uniform array enabled the seeded MSCs to grow only on the silica particles, forming uniform-sized semi-spheroids within 48 h. These MSC spheroids have been shown to have enhanced stemness, anti-inflammatory, and immunomodulatory functions, as revealed by the increased expression of stem cell markers (Oct4, Sox2, and Nanog), anti-inflammatory (IL-10, TSG6, and IDO), and immunomodulatory molecules (HGF, VEGF, CXCR4) both at mRNA and protein expression levels. Furthermore, these MSC spheroids demonstrated an increased palliative effect on glycemic control in a multiple low-dose streptozotocin-induced diabetes model compared with the same number of MSC single cell suspensions. Taken together, this study presents a new method to produce uniform-sized MSC spheroids with enhanced anti-inflammatory and immunomodulatory functions in vitro and in vivo.

Rat Milk and Plasma Immunological Profile throughout Lactation

The composition of bioactive factors with immune activity in human breast milk is widely studied. However, the knowledge on rat milk immune factors during the whole lactation period is still scarce. This study aimed to analyze rat breast milk’s immunoglobulin (Ig) content and some critical adipokines and growth factors throughout the lactation period, and to assess relationships with corresponding plasma levels. During lactation, milk concentration of the transforming growth factor (TGF)-β2 and -β3 showed a punctual increase in the first week, whereas adiponectin and leptin remained stable. In the second period of lactation (d14–21), despite the increase in the milk epidermal growth factor (EGF), a decrease in fibroblast growth factor 21 (FGF21) was detected at day 21. Milk IgA concentration had a progressive increase during lactation, while no significant changes were found in IgM and IgG. Regarding plasma levels, a decrease in all studied adipokines was observed in the second period of lactation, with the exception of IgA and TGF-β1, which reached their highest values at the end of the study. A positive correlation in IgM, IgG, and adipokine concentration was detected between milk and plasma compartments. In summary, the changes in the pattern of these bioactive compounds in rat milk and plasma and their relationships during lactation are established.

Immunotherapy and predictive immunologic profile: the tip of the iceberg

The interplay between cancer and the immune system has been under investigation for more than a century. Immune checkpoint inhibitors have changed the outcome of several tumors; however, there is a significant percentage of patients presenting resistance to immunotherapy. Besides the action mechanism, it is essential to unravel this complex interplay between host immune system and tumorigenesis to determine an immune profile as a predictive factor to immune checkpoint blockade agents. Tumor expression of programmed death-ligand 1 (PD-L1), tumor mutational burden, or mismatch repair deficiency are recognized predictive biomarkers to immunotherapy but are insufficient to explain the response rates and heterogeneity across tumor sites. Therefore, it is crucial to explore the role of the tumor microenvironment in the diversity and clonality of tumor-infiltrating immune cells since different checkpoint molecules play an influential role in cytotoxic T cell activation. Moreover, cytokines, chemokines, and growth factors regulated by epigenetic factors play a complex part. Peripheral immune cells expressing PD-1/PD-L1 and the biologic roles of soluble immune checkpoint molecules are the subject of new lines of investigation. This article addresses some of the new molecules and mechanisms studied as possible predictive biomarkers to immunotherapy, linked with the concept of immune dynamics monitoring.

Exosomes: Small EVs with Large Immunomodulatory Effect in Glioblastoma

Glioblastomas are among the most aggressive tumors, and with low survival rates. They are characterized by the ability to create a highly immunosuppressive tumor microenvironment. Exosomes, small extracellular vesicles (EVs), mediate intercellular communication in the tumor microenvironment by transporting various biomolecules (RNA, DNA, proteins, and lipids), therefore playing a prominent role in tumor proliferation, differentiation, metastasis, and resistance to chemotherapy or radiation. Exosomes are found in all body fluids and can cross the blood–brain barrier due to their nanoscale size. Recent studies have highlighted the multiple influences of tumor-derived exosomes on immune cells. Owing to their structural and functional properties, exosomes can be an important instrument for gaining a better molecular understanding of tumors. Furthermore, they qualify not only as diagnostic and prognostic markers, but also as tools in therapies specifically targeting aggressive tumor cells, like glioblastomas.

The tellurium-based immunomodulator, AS101 ameliorates adjuvant-induced arthritis in rats

Despite undeniable improvement in the management of rheumatoid arthritis (RA), the discovery of more effective, less toxic and, ideally, less immune suppressive drugs are much needed. In the current study, we set to explore the potential anti-rheumatic activity of the non-toxic, tellurium-based immunomodulator, AS101 in an experimental animal model of RA. The effect of AS101 was assessed on adjuvant-induced arthritis (AIA) rats. Clinical signs of arthritis were assessed. Histopathological examination was used to assess inflammation, synovial changes and tissue lesions. Very late antigen-4 (VLA-4)+ cellular infiltration was detected using immunohistochemical staining. Enzyme-linked immunosorbent assay (ELISA) was used to measure circulating anti-cyclic citrullinated-peptide autoantibody (ACPA) and real-time polymerase chain reaction (PCR) was used to measure the in-vitro effect of AS101 on interleukin (IL)-6 and IL-1β expression in activated primary human fibroblasts. Prophylactic treatment with intraperitoneal AS101 reduced clinical arthritis scores in AIA rats (P < 0·01). AS101 abrogated the migration of active chronic inflammatory immune cells, particularly VLA-4+ cells, into joint cartilage and synovium, reduced the extent of joint damage and preserved joint architecture. Compared to phosphate-buffered saline (PBS)-treated AIA rats, histopathological inflammatory scores were significantly reduced (P < 0·05). Furthermore, AS101 resulted in a marked reduction of circulating ACPA in comparison to PBS-treated rats (P < 0·05). Importantly, AS101 significantly reduced mRNA levels of proinflammatory mediators such as IL-6 (P < 0·05) and IL-1β (P < 0·01) in activated primary human fibroblasts. Taken together, we report the first demonstration of the anti-rheumatic/inflammatory activity of AS101 in experimental RA model, thereby supporting an alternative early therapeutic intervention and identifying a promising agent for therapeutic intervention.

Membrane Microvesicles as Potential Vaccine Candidates

The prevention and control of infectious diseases is crucial to the maintenance and protection of social and public healthcare. The global impact of SARS-CoV-2 has demonstrated how outbreaks of emerging and re-emerging infections can lead to pandemics of significant public health and socio-economic burden. Vaccination is one of the most effective approaches to protect against infectious diseases, and to date, multiple vaccines have been successfully used to protect against and eradicate both viral and bacterial pathogens. The main criterion of vaccine efficacy is the induction of specific humoral and cellular immune responses, and it is well established that immunogenicity depends on the type of vaccine as well as the route of delivery. In addition, antigen delivery to immune organs and the site of injection can potentiate efficacy of the vaccine. In light of this, microvesicles have been suggested as potential vehicles for antigen delivery as they can carry various immunogenic molecules including proteins, nucleic acids and polysaccharides directly to target cells. In this review, we focus on the mechanisms of microvesicle biogenesis and the role of microvesicles in infectious diseases. Further, we discuss the application of microvesicles as a novel and effective vaccine delivery system.

Immunotherapy response modeling by ex-vivo organ culture for lung cancer

One of the major hurdles for the advancement of cancer immunotherapy is lack of robust, accessible experimental models. We aimed to produce an ex-vivo organ culture (EVOC) model of immunotherapy for non-small cell lung cancer (NSCLC). Freshly resected early stage tumors were collected from the operating room, fragmented to clusters < 450 µm and cultured with fetal calf serum and human autologous serum. The resulting EVOC includes cancer epithelial cells within tumor tissue clusters and immune cells. Original tissue features are reflected in the EVOCs. The response to immune checkpoint inhibitors (ICI) was assessed by IFNγ gene induction. Interestingly, IFNγ EVOC induction was numerically higher when anti-CTLA4 was added to anti-PD-L1 treatment, supporting the notion that anti-CTLA4 impacts cancer partly through tumor-resident immune cells. In parallel, immunohistochemistry (IHC) for key immune-related proteins was performed on the formalin-fixed paraffin embedded (FFPE) corresponding tumors. EVOC IFNγ induction by ICI correlated with basal non-induced IFNγ, CD8, CD4 and FOXP3 mRNA levels within EVOCs and with tumor-FFPE-IHC for CD8 and granzyme B. A weaker correlation was seen with tumor-FFPE-IHC for CD3, CD4, CD68, FOXP3 and tumor-PD-L1. Tertiary lymphoid structure density was also correlated with the ICI response. Our study provides novel data about biomarkers that correlate with ICI-induced response of early stage NSCLC. Retention of the microenvironment and minimal addition of exogenous factors suggest this model to reliably represent the original tumor. The cluster-based EVOC model we describe can provide a valuable, yet simple and widely applicable tool for the study of immunotherapy in NSCLC.

SP-A and SP-D: Dual Functioning Immune Molecules With Antiviral and Immunomodulatory Properties

Surfactant proteins A (SP-A) and D (SP-D) are soluble innate immune molecules which maintain lung homeostasis through their dual roles as anti-infectious and immunomodulatory agents. SP-A and SP-D bind numerous viruses including influenza A virus, respiratory syncytial virus (RSV) and human immunodeficiency virus (HIV), enhancing their clearance from mucosal points of entry and modulating the inflammatory response. They also have diverse roles in mediating innate and adaptive cell functions and in clearing apoptotic cells, allergens and other noxious particles. Here, we review how the properties of these first line defense molecules modulate inflammatory responses, as well as host-mediated immunopathology in response to viral infections. Since SP-A and SP-D are known to offer protection from viral and other infections, if their levels are decreased in some disease states as they are in severe asthma and chronic obstructive pulmonary disease (COPD), this may confer an increased risk of viral infection and exacerbations of disease. Recombinant molecules of SP-A and SP-D could be useful in both blocking respiratory viral infection while also modulating the immune system to prevent excessive inflammatory responses seen in, for example, RSV or coronavirus disease 2019 (COVID-19). Recombinant SP-A and SP-D could have therapeutic potential in neutralizing both current and future strains of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) virus as well as modulating the inflammation-mediated pathology associated with COVID-19. A recombinant fragment of human (rfh)SP-D has recently been shown to neutralize SARS-CoV-2. Further work investigating the potential therapeutic role of SP-A and SP-D in COVID-19 and other infectious and inflammatory diseases is indicated.

Topical Application of Virus-Derived Immunomodulating Proteins and Peptides to Promote Wound Healing in Mouse Models

Immune modulators play critical roles in the progression of wounds to normal or conversely delayed healing, through the regulation of normal tissue regrowth, scarring, inflammation, and growth factor expression. Many immune modulator recombinants are under active preclinical study or in clinical trial to promote improved acute or chronic wound healing and to reduce scarring. Viruses have evolved highly efficient immune modulators for the evasion of host-defensive immune responses that target and kill invasive viruses. Recent studies have proven that some of these virus-derived immune modulators can be used to promote wound healing with significantly improved speed and reduced scarring in rodent models. Mouse full-thickness excisional wound model is one of the most commonly used animal models used to study wound healing for its similarity to humans in the healing phases and associated cellular and molecular mechanisms. This chapter introduces this mouse dermal wound healing model in detail for application in studying viral immune modulators as new treatments to promote wound healing. Details of hydrogel, protein construction, and topical application methods for these therapeutic proteins are provided in this chapter.

Preclinical Testing of Viral Therapeutic Efficacy in Pristane-Induced Lupus Nephritis and Diffuse Alveolar Hemorrhage Mouse Models

Systemic lupus erythematosus (SLE) is a multifactorial and heterogeneous autoimmune disease involving multiple organ systems and tissues. Lupus nephritis occurs in approximately 60% of patients with SLE and is the leading cause of morbidity. Diffuse alveolar hemorrhage (DAH) is a rare but very serious complication of SLE with a greater than 50% associated mortality. The etiology of SLE is unclear but has proposed genetic, hormonal, and environmental aspects. Pristane is a saturated terpenoid alkane and has become the most popular laboratory model for inducing lupus in mice. The pristane model of SLE has the capacity to reproduce many components of the human presentation of the disease. Previous studies have demonstrated that virus-derived immune-modulating proteins have the potential to control inflammatory and autoimmune disorders. Serp-1, a 55 kDa secreted and highly glycosylated immune modulator derived from myxoma virus (MYXV), has potent immunomodulatory activity in models of vasculitis, viral sepsis, collagen-induced arthritis, and transplant rejection. This chapter describes the mouse preclinical pristane lupus model as a method to examine virus-derived protein efficacy for treating autoimmune diseases and specifically lupus nephritis and DAH.

Peptides that immunoactivate the tumor microenvironment

Cancer immunotherapy has achieved positive clinical outcomes and is revolutionizing cancer treatment. However, cancer immunotherapy has thus far failed to improve outcomes for most "cold tumors", which are characterized by low infiltration of immune cells and immunosuppressive tumor microenvironment. Enhancing the responsiveness of cold tumors to cancer immunotherapy by stimulating the components of the tumor microenvironment is a strategy pursued in the last decade. Currently, most of the agents used to modify the tumor microenvironment are small molecules or antibodies. Small molecules exhibit low affinity and specificity towards the target and antibodies have shortcomings such as poor tissue penetration and high production cost. Peptides may overcome these drawbacks and therefore are promising materials for immunomodulating agents. Here we systematically summarize the currently developed immunoactivating peptides and discuss the potential of peptide therapeutics in cancer immunology.

Clinical and biological activity of rituximab in the treatment of pemphigus

B-cells are major effector cells in autoimmunity since they differentiate into plasmocytes that produce pathogenic auto-antibody such as anti-desmoglein antibodies in pemphigus patients. Major advances were obtained using whole B-cell depleting therapies including anti-CD20 antibodies in refractory pemphigus patients that lead to rituximab approval in pemphigus patients in EU and USA. This review summarizes the data supporting the efficacy of rituximab in pemphigus and provides an overview of the reported immunological changes underlying its therapeutic action. Short and long-term remission in pemphigus is explained by the removal of autoreactive B-cells involved in the production of pathogenic IgG auto-antibodies and by enhancement of the appearance of regulatory B-cells that could maintain long term immune tolerance.

Deriving Immune-Modulating Peptides from Viral Serine Protease Inhibitors (Serpins)

Viruses have devised highly effective approaches that modulate the host immune response, blocking immune responses that are designed to eradicate viral infections. Over millions of years of evolution, virus-derived immune-modulating proteins have become extraordinarily potent, in some cases working at picomolar concentrations when expressed into surrounding tissues and effectively blocking host defenses against viral invasion and replication. The marked efficiency of these immune-modulating proteins is postulated to be due to viral engineering of host immune modulators as well as design and development of new strategies (i.e., some derived from host proteins and some entirely unique). Two key characteristics of viral immune modulators confer both adaptive advantages and desirable functions for therapeutic translation. First, many virus-derived immune modulators have evolved structures that are not readily recognized or regulated by mammalian immune pathways, ensuring little to no neutralizing antibody responses or proteasome-mediated degradation. Second, these immune modulators tend to target early steps in central immune responses, producing a powerful downstream inhibitory "domino effect" which may alter cell activation and gene expression.We have proposed that peptide metabolites of these immune-modulating proteins can enhance and extend protein function. Active immunomodulating peptides have been derived from both mammalian and viral proteins. We previously demonstrated that peptides derived from computationally predicted cleavage sites in the reactive center loop (RCL) of a viral serine proteinase inhibitor (serpin ) from myxoma virus, Serp-1 , can modify immune response activation. We have also demonstrated modulation of host gut microbiota produced by Serp-1 and RCL-derived peptide , S7, in a vascular inflammation model. Of interest, generation of derived peptides that maintain therapeutic function from a serpin can act by a different mechanism. Whereas Serp-1 has canonical serpin-like function to inhibit serine proteases, S7 instead targets mammalian serpins. Here we describe the derivation of active Serp- RCL peptides and their testing in inflammatory vasculitis models.

COVID-19 update: The race to therapeutic development

The COVID-19 pandemic, caused by severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), represents an unprecedented challenge to global public health. At the time of this review, COVID-19 has been diagnosed in over 40 million cases and associated with 1.1 million deaths worldwide. Current management strategies for COVID-19 are largely supportive, and while there are more than 2000 interventional clinical trials registered with the U.S. National Library of Medicine (clinicaltrials.gov), results that can clarify benefits and risks of candidate therapies are only gradually becoming available. We herein describe recent advances in understanding SARS-CoV-2 pathobiology and potential therapeutic targets that are involved in viral entry into host cells, viral spread in the body, and the subsequent COVID-19 progression. We highlight two major lines of therapeutic strategies for COVID-19 treatment: 1) repurposing the existing drugs for use in COVID-19 patients, such as antiviral medications (e.g., remdesivir) and immunomodulators (e.g., dexamethasone) which were previously approved for other disease conditions, and 2) novel biological products that are designed to target specific molecules that are involved in SARS-CoV-2 viral entry, including neutralizing antibodies against the spike protein of SARS-CoV-2, such as REGN-COV2 (an antibody cocktail), as well as recombinant human soluble ACE2 protein to counteract SARS-CoV-2 binding to the transmembrane ACE2 receptor in target cells. Finally, we discuss potential drug resistance mechanisms and provide thoughts regarding clinical trial design to address the diversity in COVID-19 clinical manifestation. Of note, preventive vaccines, cell and gene therapies are not within the scope of the current review.

Integrating Immunotherapy and Targeted Therapy in Cancer Treatment: Mechanistic Insights and Clinical Implications

Small-molecule targeted therapies have demonstrated outstanding potential in the clinic. These drugs are designed to minimize adverse effects by selectively attacking cancer cells while exerting minimal damage to normal cells. Although initial response to targeted therapies may be high, yielding positive response rates and often improving survival for an important percentage of patients, resistance often limits long-term effectiveness. On the other hand, immunotherapy has demonstrated durable results, yet for a limited number of patients. Growing evidence indicates that some targeted agents can modulate different components of the antitumor immune response. These include immune sensitization by inhibiting tumor cell-intrinsic immune evasion programs or enhancing antigenicity, as well as direct effects on immune effector and immunosuppressive cells. The combination of these two approaches, therefore, has the potential to result in synergistic and durable outcomes for patients. In this review, we focus on the latest advances on integrating immunotherapy with small-molecule targeted inhibitors. In particular, we discuss how specific oncogenic events differentially affect immune response, and the implications of these findings on the rational design of effective combinations of immunotherapy and targeted therapies.

Omega-3 fatty acids in the psychological and physiological resilience against COVID-19

As the infected cases of COVID-19 reach more than 20 million with more than 778,000 deaths globally, an increase in psychiatric disorders including anxiety and depression has been reported. Scientists globally have been searching for novel therapies and vaccines to fight against COVID-19. Improving innate immunity has been suggested to block progression of COVID-19 at early stages, while omega-3 polyunsaturated fatty acids (n-3 PUFAs) have been shown to have immunomodulation effects. Moreover, n-3 PUFAs have also been shown to improve mood disorders, thus, future research is warranted to test if n-3 PUFAs may have the potential to improve our immunity to counteract both physical and mental impact of COVID-19.

COVID-19: In the Eye of the Cytokine Storm

The dysregulated release of cytokines has been identified as one of the key factors behind poorer outcomes in COVID-19. This "cytokine storm" produces an excessive inflammatory and immune response, especially in the lungs, leading to acute respiratory distress (ARDS), pulmonary edema and multi-organ failure. Alleviating this inflammatory state is crucial to improve prognosis. Pro-inflammatory factors play a central role in COVID-19 severity, especially in patients with comorbidities. In these situations, an overactive, untreated immune response can be deadly, suggesting that mortality in COVID-19 cases is likely due to this virally driven hyperinflammation. Administering immunomodulators has not yielded conclusive improvements in other pathologies characterized by dysregulated inflammation such as sepsis, SARS-CoV-1, and MERS. The success of these drugs at reducing COVID-19-driven inflammation is still anecdotal and comes with serious risks. It is also imperative to screen the elderly for risk factors that predispose them to severe COVID-19. Immunosenescence and comorbidities should be taken into consideration. In this review, we summarize the latest data available about the role of the cytokine storm in COVID-19 disease severity as well as potential therapeutic approaches to ameliorate it. We also examine the role of inflammation in other diseases and conditions often comorbid with COVID-19, such as aging, sepsis, and pulmonary disorders. Finally, we identify gaps in our knowledge and suggest priorities for future research aimed at stratifying patients according to risk as well as personalizing therapies in the context of COVID19-driven hyperinflammation.

Associations between hypovitaminosis D and COVID-19: a narrative review

In the search for factors affecting incidence and lethality of the current COVID-19 pandemic, recent association studies explored the possible role of vitamin D deficiency. Altogether, these studies, in most cases based on cross-sectional analyses, could not yet provide a convincing demonstration of a cause-effect relationship. In this editorial, the authors describe the scientific evidence underlying a possible role of vitamin D in the prevention and development of the pandemic, considering its immunomodulatory role and antiviral effects. They conclude that further studies are needed to (1) better explore possible associations between vitamin D deficiency and COVID-19 morbidity and lethality, and (2) assess if compensating such deficiency could avoid or mitigate the worst manifestations of COVID-19. They highlight the need for public health campaigns to promote consumption of vitamin D-rich foods and proper sunlight exposition or, when this is not possible, controlled pharmaceutical supplementation, especially in countries with high prevalence of hypovitaminosis D.

Use of Intravenous Immunoglobulins in Sepsis Therapy-A Clinical View

Sepsis is a life-threatening organ dysfunction, defined by a dysregulated host immune response to infection. During sepsis, the finely tuned system of immunity, inflammation and anti-inflammation is disturbed in a variety of ways. Both pro-inflammatory and anti-inflammatory pathways are upregulated, activation of the coagulation cascade and complement and sepsis-induced lymphopenia occur. Due to the manifold interactions in this network, the use of IgM-enriched intravenous immunoglobulins seems to be a promising therapeutic approach. Unfortunately, there is still a lack of evidence-based data to answer the important questions of appropriate patient populations, optimal timing and dosage of intravenous immunoglobulins. With this review, we aim to provide an overview of the role of immunoglobulins, with emphasis on IgM-enriched formulations, in the therapy of adult patients with sepsis and septic shock.

The assembly of glycosphingolipid determines their immunomodulatory effect: A novel method for structure-based design of immunotherapy

Structure-activity relationships provide insight into the binding interactions of beta-glycosphingolipids (GSLs) with both the TCR and the CD1d molecules, as well as the subsequent immunologic response of regulatory NKT cells.

AIM

To determine the effects of synthetic GSL structures on their immune modulatory functions.

METHODS

GSLs of various structures were tested in vitro and in an animal model of Concanavalin A (ConA) immune-mediated hepatitis.

RESULTS

In vitro, using SV40 binding to live monkey CV1 cells, the l-threo stereoisomer of C8-β-LacCer inhibits caveolar internalization, reducing viral binding to the cell surface. In vivo, in the ConA model, LR172, which has a saturated C8 chain, and LR178, which has a trans double bond at C-2 in the C8 chain, suppressed the immune-mediated liver inflammation and reduced IFNγ levels in a dose dependent manner. The beneficial effects of LR172 and of LR178 are associated with suppression of liver apoptosis, increased phosphorylated STAT3 expression in the liver, and an increase in the NKT liver/spleen ratio.

SUMMARY

The assembly of GSLs determines their immunomodulatory effect and can serve as a method for structure-based design of immunotherapy.

Circulating immune cell phenotype dynamics reflect the strength of tumor-immune cell interactions in patients during immunotherapy

The extent to which immune cell phenotypes in the peripheral blood reflect within-tumor immune activity prior to and early in cancer therapy is unclear. To address this question, we studied the population dynamics of tumor and immune cells, and immune phenotypic changes, using clinical tumor and immune cell measurements and single-cell genomic analyses. These samples were serially obtained from a cohort of advanced gastrointestinal cancer patients enrolled in a trial with chemotherapy and immunotherapy. Using an ecological population model, fitted to clinical tumor burden and immune cell abundance data from each patient, we find evidence of a strong tumor-circulating immune cell interaction in responder patients but not in those patients that progress on treatment. Upon initiation of therapy, immune cell abundance increased rapidly in responsive patients, and once the peak level is reached tumor burden decreases, similar to models of predator-prey interactions; these dynamic patterns were absent in nonresponder patients. To interrogate phenotype dynamics of circulating immune cells, we performed single-cell RNA sequencing at serial time points during treatment. These data show that peripheral immune cell phenotypes were linked to the increased strength of patients' tumor-immune cell interaction, including increased cytotoxic differentiation and strong activation of interferon signaling in peripheral T cells in responder patients. Joint modeling of clinical and genomic data highlights the interactions between tumor and immune cell populations and reveals how variation in patient responsiveness can be explained by differences in peripheral immune cell signaling and differentiation soon after the initiation of immunotherapy.

Analysis of virulence and immunogenic factors in Aeromonas hydrophila: Towards the development of live vaccines

Aeromonas hydrophila, a bacterium that is widespread in aquatic environments, is responsible for causing haemorrhagic disease in both aquatic and terrestrial species. With the purpose of developing a live vaccine, herein we have investigated nine strains of A. hydrophila (Ah-01 to Ah-09) isolated from diseased fish. A study of virulence factors that contribute to pathogenicity and immunogenicity in the host Cyprinus carpio suggests that the presence of β-hly, act and fla genes contribute to pathogenesis: strains Ah-01, Ah-02 and Ah-03 (β-hly⁺ /act⁺ /fla⁺ genotype) were highly pathogenic to C. carpio, whereas Ah-05 and Ah-06 (β-hly^- /act^- /fla^- genotype) showed weak pathogenicity. Accordingly, Ah-02 and Ah-03 were selected to prepare inactivated vaccines, whereas Ah-05 and Ah-06 were chosen as live vaccines. Ah-06 live vaccine was found to have the best protective efficacy, with a protective rate of about 85%, whereas rates of other vaccines were significantly lower, in the range 37%-59%. In addition, DNA vaccines based on genes altA, aha and omp showed immune protection rates of 25%, 37.5% and 75%, respectively. Our data demonstrate that the β-hly^- /act^- /fla^- /altA⁺ /aha⁺ /omp⁺ genotype has weak pathogenicity and high immunogenicity, and provide a simple and effective way to screen for live A. hydrophila vaccines.

Immunotherapies for Aging-Related Neurodegenerative Diseases-Emerging Perspectives and New Targets

Neurological disorders such as Alzheimer's disease (AD), Lewy body dementia (LBD), frontotemporal dementia (FTD), and vascular dementia (VCID) have no disease-modifying treatments to date and now constitute a dementia crisis that affects 5 million in the USA and over 50 million worldwide. The most common pathological hallmark of these age-related neurodegenerative diseases is the accumulation of specific proteins, including amyloid beta (Aβ), tau, α-synuclein (α-syn), TAR DNA-binding protein 43 (TDP43), and repeat-associated non-ATG (RAN) peptides, in the intra- and extracellular spaces of selected brain regions. Whereas it remains controversial whether these accumulations are pathogenic or merely a byproduct of disease, the majority of therapeutic research has focused on clearing protein aggregates. Immunotherapies have garnered particular attention for their ability to target specific protein strains and conformations as well as promote clearance. Immunotherapies can also be neuroprotective: by neutralizing extracellular protein aggregates, they reduce spread, synaptic damage, and neuroinflammation. This review will briefly examine the current state of research in immunotherapies against the 3 most commonly targeted proteins for age-related neurodegenerative disease: Aβ, tau, and α-syn. The discussion will then turn to combinatorial strategies that enhance the effects of immunotherapy against aggregating protein, followed by new potential targets of immunotherapy such as aging-related processes.

A QSP model of prostate cancer immunotherapy to identify effective combination therapies

Immunotherapy, by enhancing the endogenous anti-tumor immune responses, is showing promising results for the treatment of numerous cancers refractory to conventional therapies. However, its effectiveness for advanced castration-resistant prostate cancer remains unsatisfactory and new therapeutic strategies need to be developed. To this end, systems pharmacology modeling provides a quantitative framework to test in silico the efficacy of new treatments and combination therapies. In this paper we present a new Quantitative Systems Pharmacology (QSP) model of prostate cancer immunotherapy, calibrated using data from pre-clinical experiments in prostate cancer mouse models. We developed the model by using Ordinary Differential Equations (ODEs) describing the tumor, key components of the immune system, and seven treatments. Numerous combination therapies were evaluated considering both the degree of tumor inhibition and the predicted synergistic effects, integrated into a decision tree. Our simulations predicted cancer vaccine combined with immune checkpoint blockade as the most effective dual-drug combination immunotherapy for subjects treated with androgen-deprivation therapy that developed resistance. Overall, the model presented here serves as a computational framework to support drug development, by generating hypotheses that can be tested experimentally in pre-clinical models.

Immunomodulatory Effects of Vitamin D in Thyroid Diseases

Vitamin D is a secosteroid with a pleiotropic role in multiple physiological processes. Besides the well-known activity on bone homeostasis, recent studies suggested a peculiar role of vitamin D in different non-skeletal pathways, including a key role in the modulation of immune responses. Recent evidences demonstrated that vitamin D acts on innate and adaptative immunity and seems to exert an immunomodulating action on autoimmune diseases and cancers. Several studies demonstrated a relationship between vitamin D deficiency, autoimmune thyroid disorders, and thyroid cancer. This review aims to summarize the evidences on the immunomodulatory effect of vitamin D on thyroid diseases.

CD137, an attractive candidate for the immunotherapy of lung cancer

Immunotherapy has become a hotspot in cancer therapy in recent years. Several immune checkpoints inhibitors have been used to treat lung cancer. CD137 is a kind of costimulatory molecule that mediates T cell activation, which regulates the activity of immune cells in a variety of physiological and pathological processes. Targeting CD137 or its ligand (CD137L) has been studied, aiming to enhance anticancer immune responses. Accumulating studies show that anti-CD137 mAbs alone or combined with other drugs have bright antitumor prospects. In the following, we reviewed the biology of CD137, the antitumor effects of anti-CD137 Ab monotherapy and the combined therapy in lung cancer.

New insights into the IL-12 and IL-23: From a molecular basis to clinical application in immune-mediated inflammation and cancers

The cytokines interleukin-12 (IL-12) and IL-23 share a common IL-12/IL-23p40 subunit in structure and play a central role in T cell-mediated responses in inflammation. Over-activated IL-12 and IL-23 signaling drives aberrant T helper (Th) 1 and Th17 immune responses and contributes to immune-mediated diseases. Evidence from genome-wide association studies has shown that genetic alterations in the IL-12/IL-23 signaling pathways have significant links with chronic inflammation. In addition, accumulating evidence from animal models and clinical trials has provided insights into the effectiveness of blocking the IL-12/IL-23 pathways in immune regulation, broadening the clinical indications of IL-12/IL-23 pathway effectors in immune-mediated diseases. More recently, it has been addressed that the balance between IL and 12 and IL-23 is also critical in carcinogenesis. IL-12- and IL-23-driven T cell cytokines are especially important in controlling tumor initiation, growth, and metastasis, and thus, the IL-12/IL-23 pathway may be a promising target for immunotherapy. This review focuses on IL-12/IL-23 signal transduction and biological functionality in autoimmunity and oncoimmunology. We discuss the therapeutic rationale for targeting these cytokines to treat immune-mediated diseases and issues regarding their inadvertent consequences in the balance of host defense and tumor surveillance and summarize their recent clinical applications in immune-mediated diseases.

Cholinergic signaling controls immune functions and promotes homeostasis

Acetylcholine (ACh) was created by nature as one of the first signaling molecules, expressed already in procaryotes. Based on the positively charged nitrogen, ACh could initially mediate signaling in the absence of receptors. When evolution established more and more complex organisms the new emerging organs systems, like the smooth and skeletal muscle systems, energy-generating systems, sexual reproductive system, immune system and the nervous system have further optimized the cholinergic signaling machinery. Thus, it is not surprising that ACh and the cholinergic system are expressed in the vast majority of cells. Consequently, multiple common interfaces exist, for example, between the nervous and the immune system. Research of the last 20 years has unmasked these multiple regulating mechanisms mediated by cholinergic signaling and thus, the biological role of ACh has been revised. The present article summarizes new findings and describes the role of both non-neuronal and neuronal ACh in protecting the organism from external and internal health threats, in providing energy for the whole organism and for the individual cell, controling immune functions to prevent inflammatory dysbalance, and finally, the involvement in critical brain functions, such as learning and memory. All these capacities of ACh enable the organism to attain and maintain homeostasis under changing external conditions. However, the existence of identical interfaces between all these different organ systems complicates the research for new therapeutic interventions, making it essential that every effort should be undertaken to find out more specific targets to modulate cholinergic signaling in different diseases.

Combination Immunotherapy with Passive Antibody and Sulfasalazine Accelerates Fungal Clearance and Promotes the Resolution of Pneumocystis-Associated Immunopathogenesis

The pulmonary immune response protects healthy individuals against Pneumocystis pneumonia (PcP). However, the immune response also drives immunopathogenesis in patients who develop severe PcP, and it is generally accepted that optimal treatment requires combination strategies that promote fungal killing and also provide effective immunomodulation. The anti-inflammatory drug sulfasalazine programs macrophages for enhanced Pneumocystis phagocytosis and also suppresses PcP-related immunopathogenesis. Anti-Pneumocystis antibody opsonizes Pneumocystis organisms for greater phagocytosis and may also mask antigens that drive immunopathogenesis. Thus, we hypothesized that combining antibody and sulfasalazine would have the dual benefit of enhancing fungal clearance while dampening immunopathogenesis and allow the rescue of severe PcP. To model a clinically relevant treatment scenario in mice, therapeutic interventions were withheld until clear symptoms of pneumonia were evident. When administered individually, both passive antibody and sulfasalazine improved pulmonary function and enhanced Pneumocystis clearance to similar degrees. However, combination treatment with antibody and sulfasalazine produced a more rapid improvement, with recovery of body weight, a dramatic improvement in pulmonary function, reduced lung inflammation, and the rapid clearance of the Pneumocystis organisms. Accelerated fungal clearance in the combination treatment group was associated with a significant increase in macrophage phagocytosis of Pneumocystis Both passive antibody and sulfasalazine resulted in the suppression of Th1 cytokines and a marked increase in lung macrophages displaying an alternatively activated phenotype, which were enhanced by combination treatment. Our data support the concept that passive antibody and sulfasalazine could be an effective and specific adjunctive therapy for PcP, with the potential to accelerate fungal clearance while attenuating PcP-associated immunopathogenesis.

Immunotherapy for Parkinson's disease

With the increasing prevalence of Parkinson’s disease (PD), there is an immediate need to interdict disease signs and symptoms. In recent years this need was met through therapeutic approaches focused on regenerative stem cell replacement and alpha-synuclein clearance. However, neither have shown long-term clinical benefit. A novel therapeutic approach designed to affect disease is focused on transforming the brain’s immune microenvironment. As disordered innate and adaptive immune functions are primary components of neurodegenerative disease pathogenesis, this has emerged as a clear opportunity for therapeutic development. Interventions that immunologically restore the brain’s homeostatic environment can lead to neuroprotective outcomes. These have recently been demonstrated in both laboratory and early clinical investigations. To these ends, efforts to increase the numbers and function of regulatory T cells over dominant effector cells that exacerbate systemic inflammation and neurodegeneration have emerged as a primary research focus. These therapeutics show broad promise in affecting disease outcomes beyond PD, such as for Alzheimer’s disease, stroke and traumatic brain injuries, which share common neurodegenerative disease processes.

Coordination of humoral immune factors dictates compatibility between Schistosoma mansoni and Biomphalaria glabrata

Immune factors in snails of the genus Biomphalaria are critical for combating Schistosoma mansoni, the predominant cause of human intestinal schistosomiasis. Independently, many of these factors play an important role in, but do not fully define, the compatibility between the model snail B. glabrata, and S. mansoni. Here, we demonstrate association between four previously characterized humoral immune molecules; BgFREP3, BgTEP1, BgFREP2 and Biomphalysin. We also identify unique immune determinants in the plasma of S. mansoni-resistant B. glabrata that associate with the incompatible phenotype. These factors coordinate to initiate haemocyte-mediated destruction of S. mansoni sporocysts via production of reactive oxygen species. The inclusion of BgFREP2 in a BgFREP3-initiated complex that also includes BgTEP1 almost completely explains resistance to S. mansoni in this model. Our study unifies many independent lines of investigation to provide a more comprehensive understanding of the snail immune system in the context of infection by this important human parasite.

Small Particles, Big Effects: The Interplay Between Exosomes and Dendritic Cells in Antitumor Immunity and Immunotherapy

Dendritic cells play a fundamental role in the antitumor immunity cycle, and the loss of their antigen-presenting function is a recognized mechanism of tumor evasion. We have recently demonstrated the effect of exosomes extracted from serum of patients with acute myeloid leukemia as important inducers of dendritic cell immunotolerance, and several other works have recently demonstrated the effects of these nanoparticles on immunity to other tumor types as well. The aim of this review was to highlight the recent findings on the effects of tumor exosomes on dendritic cell functions, the mechanisms by which they can lead to tumor evasion, and their manipulation as a possible strategy in cancer treatment.