Kazuya Osaki

Monocyte-Mediated Suppression of Mitogen Responses of Lymphocytes in Uremic Patients

In the present experiment, we investigated the mechanism of the suppressed mitogen responses of peripheral blood mononuclear cells (PBMC) from uremic patients. We used phytohemagglutinin (PHA) and concanavalin A (Con A) as T cell mitogens, pokeweed mitogen (PWM) as a T cell-dependent B cell mitogen, and Staphylococcus aureus Cowan I (STA) as a T cell-independent B cell mitogen. PBMC from uremic patients showed significantly suppressed responses to PHA (p less than 0.05), Con A (p less than 0.05) and STA (p less tha 0.01) compared with those from healthy controls, but there was no significant difference in PWM response. However, these suppressed responses to PHA and Con A were markedly restored by depletion of phagocytic cells from PBMC. Although STA responses were also restored markedly in uremic patients, some patients still showed lower responsiveness to STA indicating the possibility of functional B cell defects. To further clarify the mechanism of the suppressed responses to mitogens, PBMC or nonphagocytic cells from uremic patients were cocultured with control T cells in the presence of PHA, or the effects of adherent cells from uremic patients on PHA responses of autologous or allogeneic control T cells were studied. From these experiments, it was suggested that the suppressed responses of PBMC to mitogens in uremia were mediated by monocytes.

Adult T cell leukemia in hemodialysis patients from the Kagoshima district, an area in which human T cell leukemia virus type I is highly endemic.

We report 2 cases of adult T cell leukemia (ATL) from hemodialysis (HD) patients with chronic renal failure (CRF) in the Kagoshima district, an endemic area of human T cell leukemia virus type I(HTLV-I) in Japan. The positivity of antibodies to ATL-associated antigen(anti-ATLA) in HD patients, regardless of whether or not blood transfusions were given, has been higher than in healthy persons in the district (p less than 0.01). ATL is considered to break out from HTLV-I carriers. Further study should be conducted to clarify the relationship between HTLV-I infection and CRF, and moreover, attention should be directed not only to treatment of HD but accompanying ATL as well, particularly in HTLV-I-endemic areas.

Immune responses to HBs vaccine in hemodialysis patients

血液透析患者8例に不活化HBsワクチンを投与後, 抗HBs抗体産生能を検討し以下の結果を得た. 1) 血液透析患者では抗HBs抗体産生能の低下および抗体の発現時期の遅延傾向がみられた. 2) 免疫学的検索では患者の抗HBs抗体非産生群でT cell subsetsのうちOKT8陽性細胞の比率の増加がみられた. 3) in vitroのmitogenに対するリンパ球増殖能は抗体産生群と非産生群の間で特に差はみられなかった. 4) 血清免疫グロブリン, 補体, 副甲状腺ホルモンおよび血清フェリチン値は抗体産生能と関係がなかった.以上の事実より, 血液透析患者の抗HBs抗体産生能の低下は, suppressor T cellを介した免疫能抑制の機序が関与しているために起こると考えられた.