Search bioRxivSearch

Biology subjects

Ramachandran, M.

Publications and source records attributed to Ramachandran, M..

2 recordsLinked to original sources

Agonistic CD40 antibody therapy induces tertiary lymphoid structures but impairs the response to immune checkpoint blockade in glioma

Gliomas are brain tumors characterized by immunosuppression. Immunostimulatory agonistic CD40 antibodies (CD40) are in clinical development for solid tumors but are yet to be evaluated for glioma. Here, systemic delivery of CD40 led to cytotoxic T cell dysfunction and impaired the response to immune checkpoint inhibitors in preclinical glioma models. This was associated with an accumulation of suppressive CD11b+ B cells. However, CD40 also induced tertiary lymphoid structures (TLS). In human glioma, TLS correlated with increased T cell infiltration indicating enhanced immune responses. Our work unveils the pleiotropic effects of CD40 therapy in glioma, which is of high clinical relevance.

cancer biology

Essential oil composition of Callistemon citrinus (Curtis) and its protective assessment towards Tribolium castaneum (Herbst) (Coleoptera: Tenebrionidae)

Essential oil (EO) was extracted from Callistemon citrinus leaves by hydro-distillation. The extracted oil was analysed by GC and Mass Spectroscopy. Analysis report showed that the major constituent of the essential oil was eucalyptol (40.44%). The EO of C. citrinus exhibited 100% fumigation toxicity (adult mortality) against adult and 95.8% larvicidal activity against Tribolium castaneum at 160 L/L (12 hrs) and 320 L/L (48 hrs), respectively. The effective concentration of 37.05 L/L (adult) and 144.31 L/L (larva) at 24 and 48 hrs respectively. A 100% repellent activity was observed at 20 l for adult beetles and 93.3% for larvae of T. castaneum at 20 l after 24 h. Exposure to C. citrinus EO significantly reduced beetle fecundity, ovicidal activity, egg hatching, larvae survival, and emergence of adult. The effect of EO on detoxification enzymes of T. castaneum adults was examined. Results indicated that the activity of detoxification enzymes drastically varied when compared with control. This EO had toxicant effects on all stages of the life of T. castaneum. Hence it may be used as fumigant instead of the use of using synthetic chemical fumigants.

zoology