Challenges and gaps in immunosafety evaluation of therapeutics: An IQ DruSafe survey.

Immunotoxicology/immunosafety science is rapidly evolving, with novel modalities and immuno-oncology among the primary drivers of new tools and technologies. The Immunosafety Working Group of IQ/DruSafe sought to better understand some of the key challenges in immunosafety evaluation, gaps in the science, and current limitations in methods and data interpretation. A survey was developed to provide a baseline understanding of the needs and challenges faced in immunosafety assessments, the tools currently being applied across the industry, and the impact of feedback received from regulatory agencies. This survey also focused on current practices and challenges in conducting the T-cell-dependent antibody response (TDAR) and the cytokine release assay (CRA). Respondents indicated that ICH S8 guidance was insufficient for the current needs of the industry portfolio of immunomodulators and novel modalities and should be updated. Other challenges/gaps identified included translation of nonclinical immunosafety assessments to the clinic, and lack of relevant nonclinical species and models in some cases. Key areas of emerging science that will add future value to immunotoxicity assessments include development of additional in vitro and microphysiological system models, as well as application of humanized mouse models. Efforts are ongoing in individual companies and consortia to address some of these gaps and emerging science.

Lenalidomide and dexamethasone in relapsed/refractory immunoglobulin light chain (AL) amyloidosis: results from a large cohort of patients with long follow-up.

Lenalidomide and dexamethasone (RD) is a standard treatment in relapsed/refractory immunoglobulin light chain (AL) amyloidosis (RRAL). We retrospectively investigated toxicity, efficacy and prognostic markers in 260 patients with RRAL. Patients received a median of two prior treatment lines (68% had been bortezomib-refractory; 33% had received high-dose melphalan). The median treatment duration was four cycles. The 3-month haematological response rate was 31% [very good haematological response (VGHR) in 18%]. The median follow-up was 56·5 months and the median overall survival (OS) and haematological event-free survival (haemEFS) were 32 and 9 months. The 2-year dialysis rate was 15%. VGHR resulted in better OS (62 vs. 26 months, P < 0·001). Cardiac progression predicted worse survival (22 vs. 40 months, P = 0·027), although N-terminal prohormone of brain natriuretic peptide (NT-proBNP) increase was frequently observed. Multivariable analysis identified these prognostic factors: NT-proBNP for OS [hazard ratio (HR) 1·71; P < 0·001]; gain 1q21 for haemEFS (HR 1·68, P = 0·014), with a trend for OS (HR 1·47, P = 0·084); difference between involved and uninvolved free light chains (dFLC) and light chain isotype for OS (HR 2·22, P < 0·001; HR 1·62, P = 0·016) and haemEFS (HR 1·88, P < 0·001; HR 1·59, P = 0·008). Estimated glomerular filtration rate (HR 0·71, P = 0·004) and 24-h proteinuria (HR 1·10, P = 0·004) were prognostic for renal survival. In conclusion, clonal and organ biomarkers at baseline identify patients with favourable outcome, while VGHR and cardiac progression define prognosis during RD treatment.

Exopolysaccharide from Porphyridium cruentum (purpureum) is Not Toxic and Stimulates Immune Response against Vibriosis: The Assessment Using Zebrafish and White Shrimp Litopenaeus vannamei.

Exopolysaccharides, or extracellular polysaccharides (EPS, sPS), represent a valuable metabolite compound synthesized from red microalgae. It is a non-toxic natural agent and can be applied as an immunostimulant. The toxicity test of exopolysaccharides from Porphyridium has been done in vivo using zebrafish (Danio rerio) embryonic model, or the ZET (zebrafish embryotoxicity test). The administration of extracellular polysaccharides or exopolysaccharides (EPS) from microalgae Porphyridium cruentum (synonym: P. purpureum) to shrimps Litopenaeus vannamei was investigated to determine the effect of this immunostimulant on their non-specific immune response and to test if this compound can be used as a protective agent for shrimps in relation to Vibrio infection. For immune response, exopolysaccharides were given to shrimps via the immersion method on day 1 and booster on day 8. Shrimp hemocytes were taken on day 1 (EPS administration), day 7 (no treatment), day 8 (EPS booster) and day 9 (Vibrio infection) and tested for their immune response on each treatment. The result shows that the EPS is not toxic, as represented by the normal embryonic development and the mortality data. In the Pacific white shrimps, an increase in the values of all immune parameters was shown, in line with the increasing EPS concentration, except for the differential hemocyte count (DHC). In detail, an increase was noted in total hemocytes (THC) value, phagocytotic activity (PA) and respiratory burst (RB) in line with the EPS concentration increase. These results and other previous studies indicate that EPS from Porphyridium is safe, enhances immune parameters in shrimp rapidly, and has the ability to act as an immunostimulant or an immunomodulator. It is a good modulator for the non-specific immune cells of Pacific white shrimps, and it can be used as a preventive agent against vibriosis.

The effect of exposure to crude oil on the immune system. Health implications for people living near oil exploration activities.

People who reside near oil exploration activities may be exposed to toxins from gas flares or oil spills. The impact of such exposures on the human immune system has not been fully investigated. In this review, research investigating the effects of crude oil on the immune system is evaluated. The aim was to obtain a greater understanding of the possible immunological impact of living near oil exploration activities. In animals, the effect of exposure to crude oil on the immune system depends on the species, dose, exposure route, and type of oil. Important observations included; hematological changes resulting in anemia and alterations in white blood cell numbers, lymph node and splenic atrophy, genotoxicity in immune cells, modulation of cytokine gene expression and increased susceptibility to infectious diseases. In humans, there are reports that exposure to crude oil can increase the risk of developing certain types of cancer and cause immunomodulation.Abbreviations: A1AT: alpha-1 antitrypsin; ACH50: hemolytic activity of the alternative pathway; AHR: aryl hydrocarbon receptor; BALF: bronchoalveolar lavage fluid; COPD: chronic obstructive pulmonary disease; CYP: cytochrome P450; DNFB: 2, 4-dinitro-1-fluorobenzene; G-CSF: granulocyte-colony stimulating factor; IFN: interferon; IL: interleukin; 8-IP: 8-isoprostane; ISG15: interferon stimulated gene; LPO: lipid peroxidation; LTB4: leukotriene B4; M-CSF: macrophage-colony stimulating factor; MMC: melanomacrophage center; MPV: mean platelet volume; NK: natural killer; OSPM: oil sail particulate matter; PAH: polycyclic aromatic hydrocarbon; PBMC: peripheral blood mononuclear cell; PCV: packed cell volume; RBC: red blood cell; ROS: reactive oxygen species; RR: relative risk; TH: T helper; TNF: tumour necrosis factor; UV: ultraviolet; VNNV: Viral Nervous Necrosis Virus; WBC: white blood cell.

Herpesviral infections and antimicrobial protection for Alzheimer's disease: Implications for prevention and treatment.

Accumulating evidence suggests that infections by herpesviruses might be closely linked to Alzheimer's disease (AD). Pathological hallmarks of AD brains include senile plaques induced by amyloid ß peptide (Aß) in the extracellular space and intracellular neurofibrillary tangles (NFTs) consisting of phosphorylated tau protein. The prevailing hypothesis for the mechanism of AD is amyloid cascade reaction. Recent studies revealed that infections by herpesviruses induce the similar pathological hallmarks of AD, including Aß production, phosphorylation of tau (P-tau), oxidative stress, neuroinflammation, etc. Aß peptide is regarded as one of the antimicrobial peptides, which inhibits HSV-1 replication. In the elderly, reactivation of herpesviruses might act as an initiator for amyloid cascade reaction in vulnerable individuals, triggering the neurofibrillary formation of phosphorylated tau and inducing oxidative stress and neuroinflammation, which can further contribute to the accumulation of Aß and P-tau by impairing mitochondria and autophagosome. Epidemiological studies have shown AD susceptibility genes, such as APOE-ε4 allele, are highly linked to infections by herpesviruses. Interestingly, anti-herpesviral therapy significantly reduced the risk of AD in a large population study. Given that herpesviruses are arguably the most prevalent opportunistic pathogens and often reactivate in the elderly, it is reasonable to argue reactivation of herpesviruses might be major culprits for initiating AD in individuals carrying AD susceptibility genes. In this review, we summarize epidemiological and molecular evidence that support for a hypothesis of herpesviral infections and antimicrobial protection in the development of AD, and discuss the implications for future prevention and treatment of the disease.

Genotoxic and immunotoxic effects of the organophosphate metabolite diethyldithiophosphate (DEDTP) in Vivo.

Diethyldithiophosphate (DEDTP) is a metabolite produced by the degradation of organophosphorus pesticides and a dialkylphosphate that is chemically synthesized with widespread commercial use. DEDTP is a stable compound, and most studies considered it harmless. However, some studies found adverse effects in vitro, including toxicity in different human cell types. However, there are no in vivo studies characterizing the toxicological effects of DEDTP. Therefore, we investigated the genotoxicity and immunotoxicity of DEDTP in a murine model. We used C57BL/6J and Balb/c mice (6-8-weeks-old) exposed to DEDTP i.p. We established that the medium lethal dose (LD50) of DEDTP was 0.537 g/kg. DEDTP was genotoxic in vivo because it increased the frequency of micronuclei in polychromatic erythrocytes in peripheral blood at 0.05 g/kg. DEDTP showed immunotoxic effects on T and Natural Killer cells and immunomodulatory effects on macrophages, especially M2 type that increased 1000% after 20 days of exposure to 0.01 g/kg. These effects modified the response to a tumoural challenge. DEDTP exposure increased tumour size and reduced the response of lymphocytes to tumoural antigen stimulation. We conclude that exposure to DEDTP produced genotoxic and immunomodulatory effects at environmentally relevant concentrations, which affected the growth of tumours in vivo. These results suggest that DEDTP might reduce the quality of life in exposed individuals, and it exhibits genotoxicity and immunotoxicity despite its stability.

A comparative evaluation of the immunotoxicity and immunomodulatory effects on macrophages exposed to aromatic trihalogenated DBPs.

Objective: 2,4,6-trichlorophenol (TCP), 2,4,6-tribromophenol (TBP), and 2,4,6-triiodophenol (TIP) are three aromatic halogenated disinfection byproducts (DBPs) identified in chlorinated saline effluents. This study aimed to evaluate and compare their immunotoxicity and immunomodulatory effects on macrophages. Materials and methods: CCK-8 assay was used to evaluate cytotoxicity of TCP, TBP, and TIP in mouse macrophage RAW264.7 cells. A light microscope and digital camera were used to record the morphological changes of RAW264.7 cells. qRT-PCR was used to measure the mRNA levels of polarization markers and secreted cytokines. Cytokine production was also detected by ELISA. Flow cytometry was performed to analyze the expression of M1 and M2 markers on macrophages. Results: TCP, TBP, and TIP had different cytotoxic effects on macrophages. The rank order of cytotoxicity was TIP > TBP > TCP. Furthermore, the three halogenated DBPs displayed different preferences for macrophage polarization. Intriguingly, 200 µM TIP remarkably induced the M2-dominant polarization of macrophages, while 200 µM TCP induced an M1-dominant polarization of macrophages. TBP has a moderate ability in inducing M1 and M2 polarization compared with TCP and TIP. Conclusions: TIP displayed higher cytotoxicity against macrophages than TBP and TCP, its brominated and chlorinated analogs. Since M1 and M2 macrophages facilitate the inflammatory and anti-inflammatory responses, respectively, the discrepancy of TCP, TBP, and TIP in inducing macrophage polarization may lead to distinct immunomodulatory and toxicological outcomes, thus giving rise to different types of diseases. This finding may provide novel insights into evaluating the toxicity of environmental pollutants on the immune system.

Dipenyleneiodonium Induces Growth Inhibition of Toxoplasma gondii through ROS Induction in ARPE-19 Cells.

Based on the reactive oxygen species (ROS) regulatory properties of diphenyleneiodonium (DPI), we investigated the effects of DPI on host-infected T. gondii proliferation and determined specific concentration that inhibit the intracellular parasite growth but without severe toxic effect on human retinal pigment epithelial (ARPE-19) cells. As a result, it is observed that host superoxide, mitochondria superoxide and H2O2 levels can be increased by DPI, significantly, followed by suppression of T. gondii infection and proliferation. The involvement of ROS in anti-parasitic effect of DPI was confirmed by finding that DPI effect on T. gondii can be reversed by ROS scavengers, N-acetyl-L-cysteine and ascorbic acid. These results suggest that, in ARPE-19 cell, DPI can enhance host ROS generation to prevent T. gondii growth. Our study showed DPI is capable of suppressing T. gondii growth in host cells while minimizing the un-favorite side-effect to host cell. These results imply that DPI as a promising candidate material for novel drug development that can ameliorate toxoplasmosis based on ROS regulation.

Molecular cloning, codon-optimized gene expression, and bioactivity assessment of two novel fungal immunomodulatory proteins from Ganoderma applanatum in Pichia.

Fungal immunomodulatory proteins (FIPs) have been identified from a series of fungi, especially in Ganoderma species. However, little is known about the FIPs from G. applanatum. In this study, two novel FIP genes, termed as FIP-gap1 and FIP-gap2, were cloned from G. applanatum, characterized and functionally expressed after codon optimization in Pichia pastoris GS115. Results showed that FIP-gap1 and FIP-gap2 comprised 342-bp encoding peptides of 113 amino acids, which shared a high homology with other Ganoderma FIPs. The yield of recombinant FIP-gap1 and FIP-gap2 increased significantly after codon optimization and reached 247.4 and 197.5 mg/L, respectively. Bioactivity assay in vitro revealed that both rFIP-gap1 and rFIP-gap2 could agglutinate mouse, sheep, and human red blood cells. Besides, rFIP-gap1 and rFIP-gap2 obviously stimulated the proliferation of mouse splenocytes and enhanced IL-2 and IFN-γ release. Cytotoxicity detection indicated that IC50 of rFIP-gap1 towards A549 and HeLa cancer cells were 29.89 and 8.34 µg/mL, respectively, whereas IC50 of rFIP-gap2 to the same cancer cells were 60.92 and 41.05 µg/mL, respectively. Taken together, novel FIP gaps were cloned and functionally expressed in P. pastoris, which can serve as feasible and stable resources of rFIP gaps for further studies and potential applications.

Profiling the immunotoxicity of chemicals based on in vitro evaluation by a combination of the Multi-ImmunoTox assay and the IL-8 Luc assay.

We established a luciferase reporter assay system, the Multi-ImmunoTox Assay (MITA), which can evaluate the effects of chemicals on the promoter activities of four cytokines: IL-2, IFN-γ, IL-1ß, and IL-8. We previously reported that MITA correctly reflected the change in mRNA of human whole-blood cells treated with dexamethasone, cyclosporine, FK506, or several other immunosuppressive drugs. In this study, we combined MITA with the IL-8 Luc assay to detect skin sensitization chemicals (OECD 442E) (modified MITA: mMITA) and established a data set of 60 chemicals examined by mMITA. Using the mMITA results, chemicals can be classified based on the lowest observed effect level (LOEL) of chemicals in suppressing or augmenting the promoter activities of the four cytokines. Moreover, we demonstrated that K-means clustering and hierarchical clustering of the 60 chemicals based on the LOEL for their effects on IL-2 and IL-8 promoter activities and the judgment by the IL-8 Luc assay resulted in the same 6-cluster solution: cluster 1 with preferential suppression of IL-8, cluster 2 with suppression of IL-2 and a positive IL-8 Luc assay result, cluster 3 with suppression of both IL-2 and IL-8, cluster 4 with no effects on IL-2 or IL-8 and a negative IL-8 Luc assay result, cluster 5 with suppression of both IL-2 and IL-8 and a negative IL-8 Luc assay result, and cluster 6 with preferential suppression of IL-8. These data suggest that mMITA is a promising novel high-throughput approach for detecting unrecognized immunological effects of chemicals and for profiling their immunotoxic effects.

Subchronic toxicity, immunoregulation and anti-breast tumor effect of Nordamnacantal, an anthraquinone extracted from the stems of Morinda citrifolia L.

BACKGROUND: Morinda citrifolia L. that was reported with immunomodulating and cytotoxic effects has been traditionally used to treat multiple illnesses including cancer. An anthraquinone derived from fruits of Morinda citrifolia L., nordamnacanthal, is a promising agent possessing several in vitro biological activities. However, the in vivo anti-tumor effects and the safety profile of nordamnacanthal are yet to be evaluated. METHODS: In vitro cytotoxicity of nordamnacanthal was tested using MTT, cell cycle and Annexin V/PI assays on human MCF-7 and MDA-MB231 breast cancer cells. Mice were orally fed with nordamnacanthal daily for 28 days for oral subchronic toxicity study. Then, the in vivo anti-tumor effect was evaluated on 4T1 murine cancer cells-challenged mice. Changes of tumor size and immune parameters were evaluated on the untreated and nordamnacanthal treated mice. RESULTS: Nordamnacanthal was found to possess cytotoxic effects on MDA-MB231, MCF-7 and 4T1 cells in vitro. Moreover, based on the cell cycle and Annexin V results, nordamnacanthal managed to induce cell death in both MDA-MB231 and MCF-7 cells. Additionally, no mortality, signs of toxicity and changes of serum liver profile were observed in nordamnacanthal treated mice in the subchronic toxicity study. Furthermore, 50 mg/kg body weight of nordamncanthal successfully delayed the progression of 4T1 tumors in Balb/C mice after 28 days of treatment. Treatment with nordamnacanthal was also able to increase tumor immunity as evidenced by the immunophenotyping of the spleen and YAC-1 cytotoxicity assays. CONCLUSION: Nordamnacanthal managed to inhibit the growth and induce cell death in MDA-MB231 and MCF-7 cell lines in vitro and cease the tumor progression of 4T1 cells in vivo. Overall, nordamnacanthal holds interesting anti-cancer properties that can be further explored.

Comparison of in vivo toxicity, antioxidant and immunomodulatory activities of coconut, nipah and pineapple juice vinegars.

BACKGROUND: Vinegar is widely used as a food additive, in food preparation and as a food supplement. This study compared the phenolic acid profiles and in vivo toxicities, and antioxidant and immunomodulatory effects of coconut, nipah and pineapple juice vinegars, which were respectively prepared via a two-step fermentation using Saccharomyces cerevisiae 7013 INRA and Acetobacter aceti vat Europeans. RESULTS: Pineapple juice vinegar, which had the highest total phenolic acid content, also exhibited the greatest in vitro antioxidant capacity compared to coconut juice and nipah juice vinegars. Following acute and sub-chronic in vivo toxicity evaluation, no toxicity and mortality were evident and there were no significant differences in the serum biochemical profiles between mice administered the vinegars versus the control group. In the sub-chronic toxicity evaluation, the highest liver antioxidant levels were found in mice fed with pineapple juice vinegar, followed by coconut juice and nipah juice vinegars. However, compared to the pineapple juice and nipah juice vinegars, the mice fed with coconut juice vinegar, exhibited a higher population of CD4+ and CD8+ T-lymphocytes in the spleen, which was associated with greater levels of serum interleukin-2 and interferon-γ cytokines. CONCLUSIONS: Overall, the data suggested that not all vinegar samples cause acute and sub-chronic toxicity in vivo. Moreover, the in vivo immunity and organ antioxidant levels were enhanced, to varying extents, by the phenolic acids present in the vinegars. The results obtained in this study provide appropriate guidelines for further in vivo bioactivity studies and pre-clinical assessments of vinegar consumption. © 2017 Society of Chemical Industry.

Neurological toxicities associated with immune-checkpoint inhibitors.

PURPOSE OF REVIEW: Immune-checkpoint inhibitors (ICIs) constitute a novel class of agents recently approved to treat a number of human malignancies. Due to their immunomodulatory mechanism of action, ICIs can generate a wide range of immune-related adverse events (irAEs) of which neurological toxicities are of special interest because of their potential severity. The objective of this review is to examine the recent literature describing neurological irAEs and discuss their optimal management. RECENT FINDINGS: As opposed to irAEs involving other organs, neurological complications of ICIs are uncommon. These complications encompass various toxicities of the central and peripheral nervous systems, including myositis, myasthenia gravis, demyelinating polyradiculoneuropathy, meningitis and encephalitis. Neurologic irAEs are often responsive to corticosteroids and other immune-modulating treatments (e.g. plasmapheresis, intravenous immunoglobulin), which have been used in patients presenting with severe neurologic irAEs or irAEs unresponsive to corticosteroids. Data from literature indicate that early treatment is critical for reducing the morbidity associated with neurologic irAEs. SUMMARY: ICI-associated irAEs constitute a new group of neurologic complications of systemic anticancer therapies. Although potentially severe, these rare neurologic toxicities are often responsive to immune-modulating therapies. Early recognition and treatment is crucial for timely improvement of functional outcome and requires a multidisciplinary approach.

Polyomavirus-associated Prostatitis in Wistar Han Rats Following Immunosuppression in a Chronic Toxicity Study.

Chronic prostatitis characterized on light microscopic examination by moderate, multifocal, predominantly lymphocytic inflammation associated with epithelial atypia and intranuclear and cytoplasmic inclusion-like material was identified in the prostate gland of 2 Wistar Han rats administered an immunomodulatory test article in a 6-month chronic toxicity study. Transmission electron microscopy of the prostate glands identified 45-nm, nonenveloped, icosahedral virions arranged in paracrystalline array within the cell nuclei in 1 of the 2 rats. The size, shape, location, and array pattern were most consistent with a polyomavirus. The light and electron microscopic findings after immunosuppression in our case have a resemblance to a polyomavirus recently reported to affect prostate gland epithelium in a colony of immunocompromised X-linked severe combined immune deficiency rats. To the best of our knowledge, this is the first report of light and electronic microscopic lesions in the reproductive tract associated with polyomavirus following chronic immunosuppression in a widely used, wild-type Wistar Han rat.

Aryl thiosemicarbazones: In vitro and immunomodulatory activities against L. amazonensis.

Leishmaniasis is an infection caused by different species of Leishmania genus. Currently, there is no vaccine available for Leishmania infections in humans and conventional treatments are limited due to side effects. Therefore, the development of new antileishmanial drugs is an urgent need. In present study, we evaluated the cytotoxicity in host cells, leishmanicidal activity and immunomodulatory potential of seven aryl thiosemicarbazones. Host cell cytotoxicity was determined in peritoneal macrophages of BALB/c mouse, antiparasitic activity was determined against promastigotes and amastigotes of WHOM/00LTB 0016 strain of L. amazonensis. Nitric oxide (NO) production, interleukin (IL)-12, IL-10 and TNF-alpha secretion were measured in the supernatant of uninfected and infected macrophage cultures. It was observed that aryl thiosemicarbazones presented in vitro antiparasitic activity against both extracellular and intracellular forms of L. amazonensis. However, unlike Amphotericin B, these compounds displayed low cytotoxicity towards host cells. In addition to observed antiparasitic activity, compounds exhibited modulatory properties in the secretion of cytokines and nitrite content from uninfected stimulated and L. amazonensis-infected macrophages. In conclusion, we demonstrated the in vitro antiparasitic activity against L. amazonensis for aryl thiosemicarbazones, which is possible achieved by Th1 cytokine profile modulation. These findings are potential useful for drug development against cutaneous leishmaniasis.

In vitro characterization and in vivo toxicity, antioxidant and immunomodulatory effect of fermented foods; Xeniji™.

BACKGROUND: Xeniji, produced by fermenting various types of foods with lactic acid bacteria and yeast, has been commonly consumed as functional food. However, nutrition value, bioactivities and safety of different fermented products maybe varies. METHODS: Organic acid and antioxidant profiles of Xeniji fermented foods were evaluated. Moreover, oral acute (5 g/kg body weight) and subchronic toxicity (0.1, 1 and 2 g/kg body weight) of Xeniji were tested on mice for 14 days and 30 days, respectively. Mortality, changes of body weight, organ weight and serum liver enzyme level were measured. Liver and spleen of mice from subchronic toxicity study were subjected to antioxidant and immunomodulation quantification. RESULTS: Xeniji was rich in ß-carotene, phytonadione, polyphenol, citric acid and essential amino acids. No mortality and significant changes of body weight and serum liver enzyme level were recorded for both oral acute and subchronic toxicity studies. Antioxidant level in the liver and immunity of Xeniji treated mice were significantly upregulated in dosage dependent manner. CONCLUSION: Xeniji is a fermented functional food that rich in nutrients that enhanced antioxidant and immunity of mice. Xeniji that rich in ß-carotene, phytonadione, polyphenol, citric acid and essential amino acids promote antioxidant and immunity in mice without causing toxic effect.

Immunomodulatory activity of Buchholzia coriacea seed methanol extract on Trypanosoma brucei brucei infected mice.

CONTEXT: The seeds of Buchholzia coriacea Engler (Capparaceae) are used in Eastern Nigeria to treat feverish conditions, and to treat malaria and sleeping sickness that cause fever. OBJECTIVE: The current study assesses the immunomodulatory activity of Buchholzia coriacea seed extract on Trypanosoma brucei brucei infected mice. MATERIALS AND METHODS: Delayed hypersensitivity reaction, humoral antibody response and in-vivo leucocyte mobilization tests were assessed in three different experiments to determine the effect of the extract on immune response. Seventy-five (75) mice (25 mice per experiment) were used for the study and were each infected with 1.00 × 106 trypanosomes intra-peritoneally. Groups A, B and C were given 250, 500 and 1000 mg/kg of the extract, respectively, group D received 7.5 mg/kg body weight of levamisole and group E was the control. Sheep RBCs were used as antigen. RESULTS: The acute toxicity tests did not cause clinical signs or death within 24 h post treatment at all the doses tested. The extract inhibited delayed hypersensitivity reaction by 20.9 and 20.8% at 250 and 500 mg/kg, respectively, while at 1000 mg/kg, the paw size increased (-101.9%) when compared with the control. The extract elevated the antibody titre from 1.60 ± 0.40 for control to 8.00 ± 3.58 for 500 mg/kg group. The extract increased in total leucocytes counts. DISCUSSION AND CONCLUSION: The extract has a very wide safety margin and was able to improve immune response. The results of the present study showed that Buchholzia coriacea seed methanol extract possesses immunostimulatory activity on trypanosome-infected mice.

The immunomodulation potential of the synthetic derivatives of benzothiazoles: Implications in immune system disorders through in vitro and in silico studies.

Benzothiazole and its natural or synthetic derivatives have been used as precursors for several pharmacological agents for neuroprotective, anti-bacterial, and anti-allergic activities. The objective of the present study was to evaluate effects of benzothiazole analogs (compounds 1-26) for their immunomodulatory activities. Eight compounds (2, 4, 5, 8-10, 12, and 18) showed potent inhibitory activity on PHA-activated peripheral blood mononuclear cells (PBMCs) with IC50 ranging from 3.7 to 11.9 µM compared to that of the standard drug, prednisolone <1.5 µM. Some compounds (2, 4, 8, and 18) were also found to have potent inhibitory activities on the production of IL-2 on PHA/PMA-stimulated PBMCs with IC50 values ranging between <4.0 and 12.8 µM. The binding interaction of these compounds was performed through silico molecular docking. Compounds 2, 8, 9, and 10 significantly suppressed oxidative burst ROS production in phagocytes with IC50 values between <4.0 and 15.2 µM. The lipopolysaccharide (LPS)-induced nitrites in murine macrophages cell line J774 were found to be inhibited by compounds 4, 8, 9, and 18 at a concentration of 25 µg/mL by 56%, 91%, 58%, and 78%, respectively. Furthermore, compounds 5, 8, 12, and 18 showed significant (P<0.05) suppressive activity on Th-2 cytokine, interleukin 4 (IL-4) with an IC50 range of <4.0 to 40.3 µM. Interestingly compound 4 has shown a selective inhibitory activity on IL-2 and T cell proliferation (naïve T cell proliferation stage) rather than on IL-4 cytokine, while compound 12 displayed an interference with T-cell proliferation and IL-4 generation. Moreover compound 8 and 18 exert non-selective inhibition on both IL-2 and IL-4 cytokines, indicating a better interference with stage leading to humoral immune response and hence possible application in autoimmune diseases.

Translational immunotoxicology of immunomodulatory monoclonal antibodies.

While immunomodulatory monoclonal antibodies (mAbs) have a wide therapeutic potential, exaggerated immunopharmacology may drive both acute and delayed immunotoxicity. The existing tools for immunotoxicity assessment do not accurately predict the full range of immunotoxicities observed in humans. New and optimized models, assays, endpoints and biomarkers in animals and humans are required to safeguard patients and allow them access to these often transformational therapies.

Pine bark extracts: nutraceutical, pharmacological, and toxicological evaluation.

Proanthocyanidins are among the most abundant constituents in pine bark extracts (PBEs). This review summarizes medical research on PBEs from Pinus pinaster, Pinus radiata, Pinus massoniana, and other less well characterized species. The precise mechanisms of the important physiologic functions of PBE components remain to be elucidated, but there is evidently great potential for the identification and development of novel antioxidant, anti-inflammatory, cardiovascular, neuroprotective, and anticancer medicines. Although toxicological data for PBEs are limited, no serious adverse effects have been reported. PBEs, therefore, may have potential as nutraceuticals and pharmaceuticals and should be safe for use as food ingredients.