ISSN:
1432-0878
Keywords:
Key words: Coelomocytes
;
Brown bodies
;
Immune mechanisms
;
Spherulocytes
;
Holothuria tubulosa (Echinodermata)
Source:
Springer Online Journal Archives 1860-2000
Topics:
Biology
,
Medicine
Notes:
Abstract. Brown bodies are pigmented aggregates of amoebocytes found in the coelomic cavities of most holothuroids (sea cucumbers). Brown body formation was induced by injection of carmine particles into the perivisceral coelom of Holothuria tubulosa. Formation begins with release of a fibrillar material by the spherulocytes. This fibrillar material acts as an extracellular matrix upon which amoebocytes and carmine particles collect. Amoebocytes develop an extensive pseudopodial network and progressively condense into aggregates with varying degrees of compactness. While condensing, amoebocytes either phagocytose or encapsulate carmine particles. A destructive process begins once particle aggregation is complete, resulting in numerous intracellular residual bodies and extracellular residual body-like structures, depending upon whether the carmine particles were phagocytosed or encapsulated. Induced bodies have the same ultrastructural features as naturally occurring ones. Brown bodies are progressively eliminated to the outside through coelo-rectal canaliculi, and the body cavity is essentially cleared of all induced bodies within seven days following injection.
Type of Medium:
Electronic Resource
URL:
http://dx.doi.org/10.1007/s004410050517
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