Suppression of mitogen-induced IL-2R alpha expression in PBL by serum from microfilaraemic rats chronically infected with Brugia pahangi.
To study immunological responses in filarial infections, interleukin-2 receptor alpha (IL-2R alpha) expression in the peripheral blood lymphocytes (PBL) of Lewis rats infected with Brugia pahangi was observed by flow cytometry. During infection, no increase in IL-2R alpha was observed in either microfilaraemic or amicrofilaraemic rats. The PBL of rats were stimulated with phytohaemagglutinin (PHA) and the frequency of IL-2R alpha-positivity was examined. After microfilariae appeared, the increase in the rate of IL-2R alpha-positivity in microfilaraemic rats was less than in amicrofilaraemic rats. The anergy of IL-2R alpha expression in microfilaraemic rats was restored when their lymphocytes were cultured with normal rat serum. IL-2R alpha expression in normal uninfected rats decreased when cultured with serum from microfilaraemic rats. These results suggest that microfilariae-related factors in rat serum suppress PHA-induced IL-2R alpha expression in PBL and thus inhibit cell proliferation and host immunity.
Satoh
M
M
Department of Medical Zoology, Faculty of Medicine, Tokyo Medical and Dental University, Japan. satoma@saitama-med.ac.jp
Tsukidate
S
S
Eishi
Y
Y
Tamura
N
N
Yamamoto
K
K
Fujita
K
K
D000818:Animals; D017179:Brugia pahangi / Q000276:immunology*; D002478:Cells, Cultured; D005368:Filariasis / Q000276:immunology*; D007106:Immune Sera / Q000276:immunology; D007962:Leukocytes / Q000166:cytology / Q000276:immunology / Q000378:metabolism*; D008297:Male; D008842:Microfilariae / Q000276:immunology; D018512:Parasitemia / Q000276:immunology*; D051381:Rats; D011917:Rats, Inbred Lew; D015375:Receptors, Interleukin-2 / Q000096:biosynthesis* / Q000276:immunology
D007106:Immune Sera; D015375:Receptors, Interleukin-2