Immune defense and biological responses induced by toxics in Annelida

Abstract

The phylum Annelida comprises primitive coelomates that possess specially developed cellular immunity against pathogens. Active phagocytosis by coelomocytes occurs in the struggle against bacteria in Polychaeta and Oligochaeta. Encapsulation plays an important role in defense against parasites, and experimental studies have demonstrated that cooperation between different coelomocyte populations occurs in this process. Spontaneous cytotoxicity of coelomocytes against xenogenic or allogenic cells is analogous with that of vertebrate natural killer cells. Graft rejection is a model for studying the activity of these cells. Accelerated rejection following multiple transplantation reveals that the cellular immune defense system has a short-term memory. In humoral immunity, agglutinins aggregate foreign material and their level is enhanced by antigens; in Annelida, however, no specificity analogous to vertebrate antibodies has been revealed, except for weak specificity of some antigen-binding proteins. Hemolytic substances have been detected, particularly in Oligochaeta, where a fetidin possesses bactericidal activity. Lysozyme and some antibacterial proteins also occur in Polychaeta. Annelida react to physical and chemical insults by various processes. These responses are mainly due to synthesis of stress-induced proteins, inhibition of enzyme activity, and modulation (inhibition or stimulation) of the activity of enzymes involved in the detoxification of xenobiotics. Moreover, these responses frequently differ from those of vertebrates, particularly in terms of the nature of inducers. In other respects, these responses are extremely variable in Annelida, even in closely related species.

An optimization procedure for determination of metallothionein by square wave cathodic stripping voltammetry: application to marine worms

“…The MTLP content is however a crucial parameter, since in N. diversicolor, MTLP-sharing characteristics with vertebrate MTs such as inducibility and affinity to toxic metals have been reported to play a role in the detoxification process. These MT-like molecules differ in their higher contents of glycine (up to 18%) and aromatic amino acids [23]. For this experiment, the values obtained by the modified Brdička procedure in laboratories in Nantes and Angers were considered as the reference value.…”

Immuno-defense Strategy in Earthworms: A Review Article

“…This make them model organism for immunological studies (Cooper and Roch, 2003;Bilej et al, 2010). Majority of study has been done on vertebrate's immunity but very limited information available (Bilej et al, 2010) in concern with invertebrates including, earthworm's immunity (Dainaut and Scaps, 2001). During the life cycle of various commercial products, the chemical toxicants like heavy metals, pesticides, hydrocarbons and nanoparticles may be released from these products through normal use that may reaches in wastewater streams that became threat to soil 80 ecosystems.…”

“…This immune response bears long lasting memory may be life long to act against the same antigen in future security. Annelids are supposed to be the first animal in Phylogenetic tree in which both cellular and humoral immune responses are developed (Dainaut and Scaps, 2001). …”

Size-associated Variation and Factors Affecting the Morphology of Brown Bodies in Glycera tridactyla (Polychaeta:Glyceridae)

“…Immunity can be defined as a shield, created by the organism against external environmental effects (Dhainaut and Scaps 2001). The role of the cellular reactions is very important in the immunity defense mechanisms of invertebrates (Porchet-Henneré et al 1987).…”