The immunomodulating effect of the microsporidan Glugea stephani on the humoral response and immunoglobulin levels in winter flounder, Pseudopleuronectes americanus

Abstract

A quantitative study of serum immunoglobulin levels and haemagglutination titres has shown that an injection of the microsporidan GIugeu stephanicaused a decrease in the humoral response of the winter flounder. These examples demonstrate the effect of temperature on the decrease in total IgM levels and haemagglutination titres in winter flounder simultaneously injected with either G. siephuni or horse red blood cells.Transfer of serum from fish injected with spores 3 weeks earlier may also implicate soluble serum factors, such as prostaglandins or leukotrienes, causing the observed decrease in serum IgM levels.

Tetramicra brevifilum, a potential threat to farmed turbot Scophthalmus maximus

“…These low values support the work of Laudan et al (1987) in which immunosuppression was detected in serum of winter flounder infected with Glugea stephani. A possible explanation for the decrease of serum antibody in the infected turbot is that soluble serum factors secreted by the parasite may affecting the T and B cells directly.…”

“…(Hagenmiiller, 1889) and Microsporidiurn ovoideum (Thelohan, 1895) Sprague, 1977 have been reported in marine cultures of flounder Pleuronectes platessa L. (McVicar 1975, 1978, McVicar & McKenzie 1977, and Microsporidiurn senolae Egusa, 1982 (perhaps a species of Pleistophora) has caused severe mortalities in juveniles of Senola quinqueradiata (see Lom 1984). Also, G. stephani suppresses the immune response of winter flounder Pseudopleuronectes americanus (Walbaum) (Laudan et al 1987(Laudan et al , 1989.…”

Humoral Immune Response of Ayu, Plecoglossus altivelis to Glugea plecoglossi (Protozoa: Microspora).

“…Studies on immune responses of teleosts to microsporidians have started recently and some authors have described about humoral immune responses to fish microsporidians (Laudan et al, 1986a(Laudan et al, , 1986bLeiro et al, 1993;Hung et al, 1996).However, most studies were focused on immunosuppression elicited by microsporidian infections (Laudan et al, 1986a(Laudan et al, , 1986b(Laudan et al, , 1987(Laudan et al, , 1989Wongtavatchaiet al, 1995) and only Leiro et al (1993) and Hung et al (1996) reported that fish can produce specific antibodies against microsporidians. The experiments conducted in this study revealed that ayu can produce antibodies against G. plecoglossi spores.…”

“…In some cases, acquired immuni ty is well established but in other cases, immune responses are not elicited against a parasite because the parasite itself mimics its host tissues or adsorbs host antigens (Woo, 1992) . Immunodepression has been known to be caused by some microsporidian infections (Laudan et al, 1986a(Laudan et al, , 1986b(Laudan et al, , 1987(Laudan et al, , 1989Wongtavatchai et al, 1995) . In contrast, specific humoral immune responses to some microsporidians were reported by Leiro et al (1993) and Hung et al (1996).…”

Ultrastructural observations on the phagocytic behavior of winter flounder Pleuronectes americanus peritoneal neutrophils and macrophages in vivo

“…With the exception of the earlier work of Bridges et al (1976) on the basic hematology of winter flounder and an in vitro study on the phagocytic and bactericidal capability of their macrophages (Daniels 1988), there are no detailed studies on the leukocytes of this species. Our knowledge of the immune system in winter flounder is at present limited to studies on their antibody responses after exposure to a variety of antigens under either natural (Robohm et al 1979) or experimental conditions (Stolen et al 1984, Laudan et al 1987, 1989.…”