Immune Responses and Protective Immunity in Pangasius Pangasius (Hamilton, 1822) as Induced by Outer Membrane Proteins of Edwardsiella Tarda and Aluminium Hydroxide Adjuvant Complex

Edwardsiella tarda is considered one of the important bacterial fish pathogens. The outer membrane proteins (OMPs) of E. tarda are structurally and functionally conserved, and immunogenic. This study assessed the effects of the OMPs of E. tarda CGH9 as a vaccine without aluminium hydroxide [AH] (T1) and with AH adjuvant (T2) on the respiratory burst (ROB) activity, lymphocyte proliferation of head kidney (HK) leukocytes, and serum antibody production in pangas catfish Pangasius pangasius. The ROB activity and lymphocyte proliferation of HK leukocytes increased in both vaccinated groups compared to control. Nonetheless, the T2 group showed a gradual increase in ROB activity and lymphocyte proliferation of HK leukocytes up to 3-weeks post-vaccination (wpv). The serum antibody production in the T1 group decreased initially for up to 2-wpv and increased from 3-wpv; whereas, in the T2 group, the serum-specific antibody levels were significantly high from 1-wpv compared to control. Simultaneously, the protective efficacy in terms of relative percentage survival (RPS) in the T2 group after injecting with a lethal dose of E. tarda CGH9 was high (89.00±15.56) compared to the T1 group (78.00±0.00). Furthermore, the catfish administered with a booster dose of E. tarda OMPs with or without AH adjuvant showed no additional increase in immune response or protective immunity. These results suggested that E. tarda OMPs and AH adjuvant complex has a higher potential to induce protective immunity, which may be a good choice as a vaccine to combat E. tarda infection in catfish.

The effects of dimethyl fumarate and fingolimod on T-cell lymphocyte proliferation in patients with multiple sclerosis

Objective The disease-modifying therapies (DMT), dimethyl fumarate (DMF) and fingolimod (FTY) improve the outcomes in multiple sclerosis (MS) by reducing relapses and numbers and volume of lesions. They mediate their effects through reduction of immune reactivation, which may potentially lead to lymphopaenia and increased risk of infections. Previous studies have examined the effects of these therapies on lymphocyte subsets; however, the in vivo effects on circulating lymphocyte proliferation require further elucidation. The aim of this study was to determine the effects of DMF and FTY on T-cell proliferation in patients with MS. Method We examined T-cell lymphocyte proliferation and lymphocyte subsets in ten patients (five on DMF, five on FTY) before starting DMT and again 4 to 11 months after being maintained on DMT. Results In the FTY-treated group, the mean percentage proliferation was significantly lower using both assays (PHA assay mean percentage change − 51.2 ± 25.97, p < 0.05; anti-CD3/CD28 assay mean percentage change − 39.74 ± 27.85, p < 0.05). There was no statistical difference in T-cell lymphocyte proliferation in the DMF-treated group for either assay (PHA, p = 0.316; anti-CD3/CD28, p = 0.373). Conclusions This pilot study suggests that the T-lymphocytes of patients on FTY have an abnormal proliferation response as well as being reduced in the circulation.

Immunomodulatory effect of petroleum ether extract and ethyl acetate fraction of bengkoang (Pachyrhizus erosus (L.) Urban) in vitro

Bengkoang (Pachyrhizus erosus (L.) Urban) contains phytosterol and the isoflavone daidzein, which are thought to have immunomodulatory activity. There have been no studies reporting on the immunomodulatory effects of bengkoang extract containing polar and semi-polar compounds, such as phytosterols and isoflavone-like compounds. The objective of this study was to evaluate the immunomodulatory effects of bengkoang extracts, including petroleum ether extract (PEE), methanol extract (ME), and the ethyl acetate fraction (EAF) of bengkoang, in vitro. The immunomodulatory effects of PEE, ME, and EAF of bengkoang were determined according to the phagocytic activity of macrophages based on phagocytosis of latex beads, lymphocyte proliferation, and detection of cytokine production of tumor necrosis factor-α (TNF-α) interleukin-6 (IL-6), and interleukin-10 (IL-10) levels. Results: The phagocytic index and phagocytic capacity of ME, PEE, and EAF of bengkoang on macrophage cells were significantly increased (p < 0.05), whereas lymphocyte proliferation was unchanged compared with the control (p > 0.05), and ME of bengkoang enhanced the levels of the cytokines TNF-α and IL-6. In contrast, PEE and EAF of bengkoang decreased TNF-α and IL-6 levels compared with the control group. All of the bengkoang extracts decrease the production of the anti-inflammatory cytokine IL-10. In conclusion, this study showed that PEE, ME, and EAF of bengkoang could increase the non-specific immune response (phagocytic activity) but had a lesser effect on the specific immune response (lymphocyte proliferation). The ME of bengkoang acts as an immunostimulant by increasing the levels of the inflammatory cytokines TNF-α and IL-6 and decreasing those of the anti-inflammatory cytokine IL-10.

PHYSIOLOGICAL PREDICTORS OF LONG-TERM EFFECTS OF COVID-19 IN PATIENTS WITH SARS-COV-2: FOCUS ON LYMPHOCYTE PROLIFERATION-IMPROVING MICRONUTRIENTS

Patients with long-term effects of coronavirus disease, the so-called “long-term COVID-19 syndrome” (long-COVID-19) after SARS-CoV-2 infection, have a postponed recovery lasting from 4 weeks and up to six months, spread worldwide. Physiological predictors based on human blood biomarkers and host-virus responses to SARS-CoV-2 are still unknown. There is growing evidence about the impact of micronutrients on improving lymphocyte proliferation and their essential roles for a functioning human immune system and regulating metabolic health. This paper aims to review information about micronutrients in patients with SARS-CoV-2 infection that determines long-COVID-19 outcomes and highlight the importance of diagnostics in predictors of long-COVID-19. We reviewed articles returned from searches on PubMed/SCOPUS/Web of Science/ EMBASE databases using a combination of terms “long COVID-19”, “long-term effects of COVID-19”, “post-COVID-19 symptoms”, “COVID-19 associated stress”, “micronutrients”. Evidence indicates the relationship between lymphocyte proliferation improving micronutrient level and long-COVID-19 induction. Zinc, selenium, iron, manganese have an immunomodulatory function in innate and adaptive immune responses to viral infection. Anti-inflammatory functions of Vits A and B groups include the regulation of lymphocyte proliferation and metabolic health. Further research using sampling and artificial intelligence-assisted algorithms could assist in the recognition of the correlation of micronutrients and long-COVID-19 clinical outcomes

The Potential of Snail Seromucous and Chitosan as Bioimunomodulator for Tuberculosis Therapy

Tuberculosis (TB) as a global emergency is a chronic disease caused by Mycobacterium tuberculosis (Mtb). Mtb plays an important role in inducing or suppressing the production of Interferon Gamma (IFNG) and IL-4 in the regulation of TB homeostasis and pathogenesis. The bioactive compounds of the snail seromucous (Achatina fulica Ferussac) and chitosan function as biological response modifiers. The study aimed to determine the potential effectiveness of snail seromucous and chitosan as bio-immunomodulator for TB therapy. The research method was based on the results of laboratory experiments with the physic-chemical, biochemical, microbiological examination, snail seromucous protein profile, lymphocyte proliferation, measurement of IFNG, and IL-4 levels. The results of the physic-chemical examination of the snail seromucous showed a specific gravity of 1.010; pH 8, glucose 16 mg/dL; cholesterol 9 mg/dL; protein 2.8 mg/dL and heavy metals (Pb, Cu, Hg, Al) negative. The results of microbiological tests showed that a 100% concentration of snail seromucous was antimicrobial against Staphylococcus aureus, Candida albicans, and Pseudomonas aeruginosa. The protein profile of snail seromucous shows that there are 3 protein subunits, namely the range 55 - 72 kDa and 1 specific protein sub-unit 43 kDa as a bioactive compound achasin sulfate. Addition of chitosan dose of 65 µg/mL; snail seromucous dose of 65 µg/mL and a mixture of chitosan (65 µg/mL): snail seromucous (65 µg/mL) ratio 1: 1, can increase lymphocyte proliferation; optimum levels of IFN-γ and IL-4. Snail seromucous and chitosan are effective immunomodulators and potential candidates for TB therapy.

Phase I study of single agent NIZ985, a recombinant heterodimeric IL-15 agonist, in adult patients with metastatic or unresectable solid tumors

BackgroundNIZ985 is a recombinant heterodimer of physiologically active interleukin (IL-)15 and IL-15 receptor alpha. In preclinical models, NIZ985 promotes cytotoxic lymphocyte proliferation, killing function, and organ/tumor infiltration, with resultant anticancer effects. In this first-in-human study, we assessed the safety, pharmacokinetics, and immune effects of NIZ985 in patients with metastatic or unresectable solid tumors.MethodsSingle agent NIZ985 dose escalation data are reported from a phase I dose escalation/expansion study of NIZ985 as monotherapy. Adult patients (N=14) received 0.25, 0.5, 1, 2 or 4 µg/kg subcutaneous NIZ985 three times weekly (TIW) for the first 2 weeks of each 28-day cycle, in an accelerated 3+3 dose escalation trial design. IL-15 and endogenous cytokines were monitored by ELISA and multiplexed electrochemiluminescent assays. Multiparameter flow cytometry assessed the frequency, phenotype and proliferation of peripheral blood mononuclear cells. Preliminary antitumor activity was assessed by overall response rate (Response Evaluation Criteria in Solid Tumors V.1.1).ResultsAs of March 2, 2020, median treatment duration was 7.5 weeks (range 1.1–77.1). Thirteen patients had discontinued and one (uveal melanoma) remains on treatment with stable disease. Best clinical response was stable disease (3 of 14 patients; 21%). The most frequent adverse events (AEs) were circular erythematous injection site reactions (100%), chills (71%), fatigue (57%), and fever (50%). Treatment-related grade 3/4 AEs occurred in six participants (43%); treatment-related serious AEs (SAEs) in three (21%). The per-protocol maximum tolerated dose was not reached. Pharmacokinetic accumulation of serum IL-15 in the first week was followed by significantly lower levels in week 2, likely due to more rapid cytokine consumption by an expanding lymphocyte pool. NIZ985 treatment was associated with increases in several cytokines, including interferon (IFN)-γ, IL-18, C-X-C motif chemokine ligand 10, and tumor necrosis factor-β, plus significant induction of cytotoxic lymphocyte proliferation (including natural killer and CD8+ T cells), increased CD16+ monocytes, and increased CD163+ macrophages at injection sites.ConclusionsSubcutaneous NIZ985 TIW was generally well tolerated in patients with advanced cancer and produced immune activation paralleling preclinical observations, with induction of IFN-γ and proliferation of cytotoxic lymphocytes. Due to delayed SAEs at the two highest dose levels, administration is being changed to once-weekly in a revised protocol, as monotherapy and combined with checkpoint inhibitor spartalizumab. These alterations are expected to maximize the potential of NIZ985 as a novel immunotherapy.Trial registration numberNCT02452268.

Purified Native and Recombinant Major Alternaria Alternata Allergen (Alt a 1) Induces Allergic Asthma in the Murine Model

Aeroallergens such us the spores of Alternaria alternata are described as the most important agents associated with respiratory allergies and severe asthma. Various experimental models of asthma have been developed using A. alternata extracts to study the pathogenesis of asthma, establishing the main parameters that trigger the asthmatic response. In this study, we describe a mouse model of asthma induced only by Alt a 1. To induce the allergic response, mice were challenged intranasally with the major allergen of A. alternata, Alt a 1. The presence of eosinophils in the lungs, elevated concentrations of Th2 family cytokines, lymphocyte proliferation and elevated IgE total serum levels indicated that the sensitisation and challenge with Alt a 1 induced the development of airway inflammation. Histological studies showed an eosinophilic cellular infiltrate in the lung tissue of mice instilled with Alt a 1. We demonstrate that Alt a 1 alone is capable of inducing a lung inflammatory response with an increase in IgE serum levels mimicking the allergic asthma immunoresponse when it is administered into BALB/c mice. This model will allow the evaluation of the immunoregulatory or immunotolerant capacity of several molecules that can be used in targeted immunotherapy for fungal allergic asthma.

198 Effect of Saccharomyces Cerevisiae Fermentate on Immune Cell Function Following Prolonged Head Elevation in 2-year-old Horses in Training

Horses are often restricted from lowering their heads while being transported, which prevents nasal drainage and triggers upper respiratory tract inflammation. Based on positive outcomes in other species, we hypothesized Saccharomyces cerevisiae fermentate (SCF) would modify this immune response in horses. Two-year-old Quarter Horses (mean ± SEM; initial age 22 ± 0.3 mo and BW 439 ± 3 kg) were randomly assigned to receive SCF (Diamond V, Cedar Rapids, IA; 21 g/d; n = 10) or no supplement (CON; n = 10) added to their diet (60% hay, 40% concentrate) for 60 d. Horses were exercised 4 d/wk for 30–45 min/d at light to moderate intensity. On d 57 horses were tethered with their heads elevated 35 cm above wither height for 12 h to mimic long-distance transport. Whole blood samples were obtained before and up to 72 h after stress induction to evaluate immune cell function. Data were compared using mixed model ANOVA with repeated measures. Serum cortisol (P &lt; 0.01) and blood leukocytes (P &lt; 0.05) were greater after head elevation. Lymphocyte proliferation in response to lipopolysaccharide was lower (P &lt; 0.01) following head elevation but did not differ by treatment. Lymphocyte proliferation in response to concanavalin A exhibited a time × treatment effect (P = 0.05) where it decreased in CON horses after head elevation (P &lt; 0.05) but was unchanged in SCF horses. Neutrophil phagocytosis of Streptococcus equi (a respiratory pathogen) was temporarily reduced (P &lt; 0.05) after head elevation in both treatments. A time × treatment effect (P = 0.05) was observed for phagocytosis-induced oxidative burst, where it increased in SCF (P &lt; 0.01) but did not change in CON horses. These data indicate SCF modified peripheral immune cell activity following a localized mucosal stressor. Whether these responses improve resistance to opportunistic pathogens following transport needs to be determined.

Identification of Differential Responses of Goat PBMCs to PPRV Virulence Using a Multi-Omics Approach

Peste des petits ruminants (PPR) is an acute transboundary infectious viral disease of small ruminants, mainly sheep and goats. Host susceptibility varies considerably depending on the PPR virus (PPRV) strain, the host species and breed. The effect of strains with different levels of virulence on the modulation of the immune system has not been thoroughly compared in an experimental setting so far. In this study, we used a multi-omics approach to investigate the host cellular factors involved in different infection phenotypes. Peripheral blood mononuclear cells (PBMCs) from Saanen goats were activated with a T-cell mitogen and infected with PPRV strains of different virulence: Morocco 2008 (high virulence), Ivory Coast 1989 (low virulence) and Nigeria 75/1 (live attenuated vaccine strain). Our results showed that the highly virulent strain replicated better than the other two in PBMCs and rapidly induced cell death and a stronger inhibition of lymphocyte proliferation. However, all the strains affected lymphocyte proliferation and induced upregulation of key antiviral genes and proteins, meaning a classical antiviral response is orchestrated regardless of the virulence of the PPRV strain. On the other hand, the highly virulent strain induced stronger inflammatory responses and activated more genes related to lymphocyte migration and recruitment, and inflammatory processes. Both transcriptomic and proteomic approaches were successful in detecting viral and antiviral effectors under all conditions. The present work identified key immunological factors related to PPRV virulence in vitro.