Cloning and expression of Bos indicus interleukin-4 in mammalian cells.

Dendritic cells (DC) which are located at the interface of innate and adaptive immunity are targets of infection by many RNA and DNA viruses. Advances in the ex vivo generation of monocyte derived non proliferating dendritic cells have been used for clinical application like immunotherapy. IL-4 cytokine plays essential role in the maturation and generation of DCs. Bos indicus interleukin 4 (boIL-4) 408 bp was amplified from PBMC’s and cloned in pBSIIKS+ vector. The sequence analysis showed N terminal 69 bp signal sequence and one N-glycosylation site. The phylogenetic tree analysis showed that Bos indicus IL-4 is closely related to the ruminant IL-4 and least sharing of genetic line of human and mouse IL-4. The recombinant boIL-4 protein was expressed in CHO cells which secreted a 16 kDa protein which was confirmed by SDS PAGE and western blotting. The rec-boIL-4 protein proliferated the bovine PBMC’s, decreased production of nitric oxide in antigen stimulated macrophages, and phagocytosed the micro particles confirming its activity on dendritic cells.

Comparative studies on immunoreactivity of truncated recombinant proteins of foot and mouth disease virus (FMDV) produced in E.coli and insect cells.

For effective FMD control programme, India needs large quantities of cheaper diagnostics in addition to vaccine. Diagnostic reagents produced through conventional methods may not be able to meet such requirements. Alternatively, rDNA technology using suitable heterologous systems that permit production of recombinant antigens to the most native form may be exploited. Studies conducted in our laboratory have led us to select carboxy terminal part of VP1 for expression and evaluation. The protein, which was purified from E.coli under denaturing conditions, was renatured and its reactivity was compared with the protein expressed in insect cells through recombinant baculovirus. The expressed protein in the insect cell whole lysate reacted more efficiently with antibodies raised against whole virus than the purified and renatured protein produced in E.coli. But for its lower reactivity, protein produced from E.coli was found to be suitable in type detection. In addition, the size of the protein is small (16 kD) and production and purification of it from E.coli may be cost effective. Hence, it may be exploited for FMDV typing.

Cercal sensory regulation of acetylcholinesterase in nervous system of the cockroach, Periplaneta americana.

Cercal ablation caused a significant loss in acetylcholinesterase (AChE) activity of the cercal nerves and terminal ganglion within 12 hr while a similar reduction in enzyme activity of connectives was noticed at least one day after cercectomy. The decrease in AChE activity of the nervous tissues showed a recovery toward control levels from 20 days of unilateral cercectomy whereas the bilateral cercectomy produced a continuous and irreversible decline in enzyme activity. These localized changes in AChE activity of the abdominal nervous system of the cockroach were attributed to be regulated by the cercal sensory innervation.

Glycogen utilization in tissues of toad, Bufo melanostictus under electropolarity treatment.

Electropolarity treatment (0.8V/DC/Cm) was given to the gastrocnemius muscle of B. melanostictus every day for 5 min for 5 days. The glycogen content and aldolase activity levels increased and phosphorylase 'a' activity levels decreased on cathode treatment in muscle, liver and brain while an opposed trend was observed on anode treatment. The heart showed contrasting pattern under both cathode and anode electropolarity treatments.

In vitro neutralization of the scorpion, Buthus tamulus venom toxicity.

Scorpion (Buthus tamulus) venom was subjected to neutralization by treating the venom with various chemicals such as hydrochloric acid, sodium hydroxide, thiourea, formaldehyde, zinc sulphate, acetic acid and trichloroacetic acid. The venom was also subjected to heat treatment. The levels of total protein, free amino acids and protease activity in neutralized venom decreased significantly. The decrease in venom protein and free amino acids was in proportion to the duration of the heat treatment and the concentration of chemicals used except zinc sulphate, sodium hydroxide and thiourea. Protease activity of neutralized venom samples also showed a decrease except with zinc sulphate which enhanced the enzyme activity. Intramuscular injection of formaldehyde, trichlcroacetic acid and heat treated venoms into albino rats produced low mortality while thiourea and zinc sulphate were not effective in reducing the mortality. Hydrochloric acid and acetic acid treated venoms reduced the mortality by 50% with a decrease in the symptoms of envenomation. The changes were attributed to the denaturing of venom protein by chemical and heat treatments.