Evidence of a Lytic Pathway in an Invertebrate Complement System: Identification of a Terminal Complement Complex Gene in a Colonial Tunicate and Its Evolutionary Implications.

The complement system is a pivotal component of innate immunity, extensively studied in vertebrates but also present in invertebrates. This study explores the existence of a terminal complement pathway in the tunicate , aiming to understand the evolutionary integration of innate and adaptive immunity. Through transcriptome analysis, we identified a novel transcript, BsITCCP, encoding a protein with both MACPF and LDLa domains-a structure resembling that of vertebrate C9 but with a simpler organization.

Phagocyte dynamics in the blastogenetic cycle of the colonial ascidian Botryllus schlosseri: Cell senescence, segregation and clearance after efferocytosis.

In the colonial ascidian Botryllus schlosseri, phagocytes are involved in the clearance of apoptotic cells and corpses during the periodical generation changes or takeovers (TOs) that assure the renewal of the colonial zooids. The persistent respiratory burst associated with efferocytosis, leads to the induction of senescence. Indeed, giant, senescent phagocytes are abundant in the colonial circulation at TO, whereas, in the other phases of the colonial blastogenetic cycle, they colonise the ventral islands (VIs), a series of mesenchymal niches located in the lateral lacunae of the mantle, on both sides of the subendostylar sinus.

A broad-taxa approach as an important concept in ecotoxicological studies and pollution monitoring.

Aquatic invertebrates play a pivotal role in (eco)toxicological assessments because they offer ethical, cost-effective and repeatable testing options. Additionally, their significance in the food chain and their ability to represent diverse aquatic ecosystems make them valuable subjects for (eco)toxicological studies. To ensure consistency and comparability across studies, international (eco)toxicology guidelines have been used to establish standardised methods and protocols for data collection, analysis and interpretation.