Neutrophil Granules of Red Seabream Pagrus major Infected with Metacercaria of Trematode

吸虫のメタセルカリアに寄生されたマダイの好中球顆粒

Neutrophil Granules of Red Seabream Pagrus major Infected with Metacercaria of Trematode

Creators Kondo Masakazu

Creators Yasumoto Shinya

Two types of granules were observed in the neutrophils of red seabream Pagrus major infected with metacercaria (species unidentified). No inflammatory symptom such as swelling and hemorrhage was observed around the cysts. Both granule types had similar morphologies but different cytochemical characteristics from those of ordinary chromophobic granules (oG-1, oG-2) in non-infected fish. In this paper, we designated the two granule-types from the fish infected with metacercaria as extraordinary chromophobic granules (type 1, eoG-1^{Mc}； type 2, eoG-2^{Mc}). The eoG-1^{Mc} showed chromophobic, simple morphology (without stratified structure), peroxidase (PO) positive, Sudan black B (SBB) negative and lack lysozomal enzymes. The eoβG-2^{Mc} was stratified granule with two-layer structure [inner eosinophilic layer (L0) and outer chromophobic layer (L1)] and SBB negative. Beta-glucuronidase and PO were detected in L0 and L1, respectively. Spot formation, a curious phenomenon appeared in PO-stained oG-2 (positive L1 and negative L0), was not observed in the present specimen. Acid phosphatase (AcP) and esterases were localized in the small central area of L0. Therefore, L0 consists of L0-0 (inner part in L0； AcP and esterases positive) and L0-1 (outer part in L0).

[ISSN]0370-9361