Aqueous humor cytokines and cellular profiles in pediatric ocular granulomas caused by theTrematode Fluke Procerovum sp.

BACKGROUND: Children from coastal areas of South India develop granulomatous eye disease after swimming in their village ponds, the causative organism being trematode Procerovum. AIM: To understand the pathogenesis by analyzing the cellular profile, cytokines, and chemokines of aqueous fluid. METHODS: This was a prospective study over 1 year on pediatric patients with ocular granuloma caused by a Trematode Fluke Procerovum sp. Granuloma was aspirated along with 100 µl volume of aqueous humor. Immunohistochemical analysis of granuloma was performed. Bio-Plex Pro™ Human Cytokine 17-plex Assay (M5000031YV) was used to measure cytokine and chemokines. RESULTS: The immunohistochemistry revealed predominantly eosinophils, followed by macrophages (CD68+) and T - lymphocytes (CD4+). Both T-helper (Th) 1 and 2 mediated cytokines and chemokine levels were significantly high. As the disease duration increased, direct Th1 response reduced and was replaced by IL-12 and IL-17 mediated secondary Th1 response. CONCLUSION: Procerovum associated granulomatous disease is immunologically characterized by Th1 and Th2 cell-mediated responses. A balance between both arms maintains the eyes between granulomatous inflammation and healing by fibrosis.

Conus venom fractions inhibit the adhesion of Plasmodium falciparum erythrocyte membrane protein 1 domains to the host vascular receptors.

Using high-throughput BioPlex assays, we determined that six fractions from the venom of Conus nux inhibit the adhesion of various recombinant PfEMP-1 protein domains (PF08_0106 CIDR1α3.1, PF11_0521 DBL2ß3, and PFL0030c DBL3X and DBL5e) to their corresponding receptors (CD36, ICAM-1, and CSA, respectively). The protein domain-receptor interactions permit P. falciparum-infected erythrocytes (IE) to evade elimination in the spleen by adhering to the microvasculature in various organs including the placenta. The sequences for the main components of the fractions, determined by tandem mass spectrometry, yielded four T-superfamily conotoxins, one (CC-Loop-CC) with I-IV, II-III connectivity and three (CC-Loop-CXaaC) with a I-III, II-IV connectivity. The 3D structure for one of the latter, NuxVA = GCCPAPLTCHCVIY, revealed a novel scaffold defined by double turns forming a hairpin-like structure stabilized by the two disulfide bonds. Two other main fraction components were a miniM conotoxin, and a O2-superfamily conotoxin with cysteine framework VI/VII. This study is the first one of its kind suggesting the use of conotoxins for developing pharmacological tools for anti-adhesion adjunct therapy against malaria. Similarly, mitigation of emerging diseases like AIDS and COVID-19, can also benefit from conotoxins as inhibitors of protein-protein interactions as treatment. BIOLOGICAL SIGNIFICANCE: Among the 850+ species of cone snail species there are hundreds of thousands of diverse venom exopeptides that have been selected throughout several million years of evolution to capture prey and deter predators. They do so by targeting several surface proteins present in target excitable cells. This immense biomolecular library of conopeptides can be explored for potential use as therapeutic leads against persistent and emerging diseases affecting non-excitable systems. We aim to expand the pharmacological reach of conotoxins/conopeptides by revealing their in vitro capacity to disrupt protein-protein and protein-polysaccharide interactions that directly contribute to pathology of Plasmodium falciparum malaria. This is significant for severe forms of malaria, which might be deadly even after treated with current parasite-killing drugs because of persistent cytoadhesion of P. falciparum infected erythrocytes even when parasites within red blood cells are dead. Anti-adhesion adjunct drugs would de-sequester or prevent additional sequestration of infected erythrocytes and may significantly improve survival of malaria patients. These results provide a lead for further investigations into conotoxins and other venom peptides as potential candidates for anti-adhesion or blockade-therapies. This study is the first of its kind and it suggests that conotoxins can be developed as pharmacological tools for anti-adhesion adjunct therapy against malaria. Similarly, mitigation of emerging diseases like AIDS and COVID-19, can also benefit from conotoxins as potential inhibitors of protein-protein interactions as treatment.

IL-33 mediated amplification of allergic response in human mast cells.

Context: IL-33 is a pro-inflammatory cytokine that is involved in the development of chronic inflammatory diseases and the initiation of allergic inflammation in response to pathogens and acts an alarmin.Objective: Present study aims to explore the IL-33 mediated effects of histamine induced allergic inflammation in human mast cells.Materials and methods: In this study, cord blood derived CD34+ mast cells and HMC-1 cells were primed with IL-33 followed by the stimulation with histamine. We investigated the functional activation of mast cell by intracellular calcium release using calcium mobilization assay, release of granular content using degranulation assay, profiling of various inflammatory and regulatory cytokines as well as chemokines by Luminex Bioplex assay and its signaling mechanisms involved using western blot analysis.Results: In our study, we found that the IL-33 acts as a mediator in the allergic inflammation induced by the histamine. IL-33 potentiates the release of intracellular calcium and degranulation content in human mast cells. Also, it enhances the production of Th2, Th1 cytokines and chemokines and down-regulates the production of regulatory cytokine. Furthermore, it enhanced the phosphorylation of the signaling molecules such as ERK, Akt, and NFκB in activated mast cells. Therefore, IL-33 acts as a potent activator of mast cells and it can elicit inflammatory response synergistically with histamine.Conclusions: Taken together, IL-33 acts as a potent mediator by inducing the inflammatory response in activated mast cells, hence increasing their responsiveness to antigens and amplifying the allergic response.

Production and expression of RANTES (CCL5) by human disc cells and modulation by IL-1-ß and TNF-α in 3D culture.

Chemokines act as important secondary inflammatory mediators which are released by cells in response to a variety of stimuli. Chemokines bind to cell surface receptors and act as second-order cytokines with specialized functions in inflammation. The role of RANTES (Regulated upon Activation, Normal T-cell Expressed, and Secreted) (also called CCL5 (chemokine (C-C motif) ligand 5)) has received little attention to date in disc tissue. Microarray analyses of lumbar disc annulus tissue revealed that RANTES expression was significantly upregulated in more degenerated Thompson grades IV and V discs compared to expression levels in grades I, II and III discs (p=0.032). Immunolocalization confirmed the presence of RANTES in the annulus and nucleus of the disc, and localized the RANTES receptors CCR1, CCR3 and CCR5 to cells in the disc. In vitro studies with IL-1-ß and TNF-α challenges, both proinflammatory cytokines resulted in elevated levels of RANTES in conditioned media (p<0.01); TNF-α exposure, however, produced significantly greater levels than did IL-1alpha (p<0.0001), suggesting a differential regulation by TNF-α. Local production of RANTES in vivo by annulus and nucleus cells, and in vitro induction of RANTES by proinflammatory cytokines suggest that disc cells are primary effector cells as well as target cells, and thus can mediate physiological immune-related processes during disc degeneration by both autocrine and paracrine signaling.