A new role for PGRP-S (Tag7) in immune defense: lymphocyte migration is induced by a chemoattractant complex of Tag7 with Mts1

PGRP-S (Tag7) is an innate immunity protein involved in the antimicrobial defense systems, both in insects and in mammals. We have previously shown that Tag7 specifically interacts with several proteins, including Hsp70 and the calcium binding protein S100A4 (Mts1), providing a number of novel cellular functions. Here we show that Tag7–Mts1 complex causes chemotactic migration of lymphocytes, with NK cells being a preferred target. Cells of either innate immunity (neutrophils and monocytes) or acquired immunity (CD4⁺ and CD8⁺ lymphocytes) can produce this complex, which confirms the close connection between components of the 2 branches of immune response.     

Cytotoxic action of conjugates of alpha-fetoprotein and epidermal growth factor with photoheme, chlorines, and phthalocyanines

Covalently bound conjugates of alpha-fetoprotein (AFP) and epidermal growth factor (EGF) with photoheme (PH), 3-desvinyl-3-formylchlorine p6 (Chl p6), chlorine e6 (Chl e6), aluminum disulfochloride phthalocyanine (PC(Al)), and cobalt octa-4,5-carboxyphthalocyanine (teraphthal, TP(Co)) were synthesized. Their molar ratios were 1:4 for AFP-cytotoxin conjugates (cf. 1:10 for AFP-TP(Co)) and 1:2 for EGF conjugates (cf. 1:1 for EGF-PC(Al)). Dark toxicity of both protein conjugates with PH, chlorines, and PC(Al) was much lower than their phototoxicity. Studies on phototoxicity demonstrated that PC(Al) conjugates with AFP and EGF and also EGF-Chl p6 were the most effective. The cytotoxic activity (CTA) of AFP-PC(Al) and EGF-Chl p6 was 80% and of EGF-PC(Al) 64% higher than the CTA of the free drugs. Conjugates with TP(Co) were much more toxic on their activation with ascorbic acid (AA): in the presence of AA the CTA of AFP-TP(Co) and of EGF-TP(Co) was 19 and 61.1% higher, respectively, than the CTA of the free TP(Co).     

Effect of andrographolide and Kan Jang--fixed combination of extract SHA-10 and extract SHE-3--on proliferation of human lymphocytes, production of cytokines and immune activation markers in the whole blood cells culture.

The immunomodulatory properties of a diterpene lactone andrographolide and Kan Jang--a standardized fixed combination of Andrographis paniculata extract SHA-10 and Eleutherococcus senticosus extract SHE-3 were investigated. Their role on spontaneous and phytohemagglutinin (PHA)-induced proliferation of human peripheral blood lymphocytes (PBL) and on production of interferon-gamma (INF-gamma) and tumor necrosis factor-alpha (TNF-alpha) were determined in vitro. Proliferation of PBL induced by PHA was enhanced by co stimulation with andrographolide and Kan Jang. At the same time andrographolide and Kan Jang inhibit spontaneous proliferation of PBL in vitro. These preparations also have effect on the formation of INF-gamma, TNF-alpha and some immune activation markers such as neopterin (Neo), beta-2-microglobulin (beta2MG), and soluble receptor for interleukin-2 (sIL-2R or sCD25) in blood cells culture. Andrographolide and Kan Jang stimulate the INF-gamma, Neopterin and beta2MG formation, but do not have any significant effect on the production of INF-gamma and Neopterin in PHA stimulated blood cells. An opposite effect on these immune makers was observed in the PHA-stimulated blood cells: both andrographolide and Kan Jang increase the formation of TNF-alpha and beta2MG in cultivated whole blood cells. Thus, andrographolide and Kan Jang can have an in vitro effect on the activation and proliferation of immunocompetent cells as well on the production of key cytokines and immune activation markers. The results show an overall higher effect of the fixed combination as compared with the equivalent amount of the pure substance andrographolide. The data are consistent with results from clinical studies of Kan Jang and contributed to a better understanding of these results.     

The effect of phenylalanine on biosynthesis of protoberberine alkaloids in the cell culture of low meadow-rue

The addition of 7 mM phenylalanine to the nutrient medium for low meadow-rue (Thalictrum minus L.) cell culturing on the 7th or 8th day doubled berberine secretion into medium. Simultaneously, the content of phenolic compounds increased in the cells and medium. Investigation of phenylalanine ammonia-lyase (PAL) and tyrosine ammonia-lyase (TAL) activities showed that exogenous Phe activated PAL by 35% and inactivated TAL by 20%. When the crude extract was separated on DEAE-Sephacel column, two proteins were isolated. One of them displayed both PAL and TAL activities, whereas another protein displayed only PAL activity. This activity disappeared after cell culturing longer than 20 days and also under the effect of Phe at a concentration reducing alkaloid biosynthesis. Phe addition to medium also increased the content of protein in both the cells and culture medium. The proportion of low-molecular proteins in the medium increased. Testing antimicrobial activity of the medium showed that it was determined by berberine and to a lesser degree by palmatine. Protein fraction also demonstrated antimicrobial activity. An improved antimicrobial activity after Phe adding to medium resulted from alkaloid and protein accumulation. The conclusion was made that one of the mechanisms of Phe action was the control of alkaloid biosynthesis with the involvement of the enzyme system of the early steps of the phenylpropanoid pathway, which, in its turn, is one of the stages in stress-induced plant response to pathogen action.     

Antioxidant activity of extracts from Thalictrum minus suspension culture

Low meadow-rue (Thalictrum minus L.) antioxidant complex was studied in cell extracts and culture medium. Its activity was expressed as total polyphenol content in ferulic acid equivalents. In these model systems (cell extracts and culture medium) the inhibition of lipid oxidation and diphenylpicrylhydrazine reduction (EC₅₀ = 12–15 μg/ml) were observed. At the phenolic compound concentration of 8–15 μg/ml, the reducing capacity of cell extracts was equivalent to 1.5 mM ascorbic acid. At the same time, berberine, a major alkaloid synthesized by the culture, manifested a low antioxidant activity. The analysis of phenolic acid composition in low meadow-rue showed that one of the main components of its antioxidant system were caffeic, gallic, chlorogenic, and ferulic acids.     

AmylPepPred: Amyloidogenic Peptide Prediction tool

We present an efficient computational architecture designed using supervised machine learning model to predict amyloid fibril forming protein segments, named AmylPepPred. The proposed prediction model is based on bio-physio-chemical properties of primary sequences and auto-correlation function of their amino acid indices. AmylPepPred provides a user friendly web interface for the researchers to easily observe the fibril forming and non-fibril forming hexmers in a given protein sequence. We expect that this stratagem will be highly encouraging in discovering fibril forming regions in proteins thereby benefit in finding therapeutic agents that specifically aim these sequences for the inhibition and cure of amyloid illnesses.

Availability

AmylPepPred is available freely for academic use at www.zoommicro.in/amylpeppred