Mitchel M. Yokoyama

Effects of Citrus Fragrance on Immune Function and Depressive States

In our previous experiments on animals evidence was found that citrus fragrance can restore the stress-induced immunosuppression, suggesting that citrus fragrance may have an effect on restoring the homeostatic balance. Since a dysregulation of the neuroendocrine and immune function is thought to be associated with psychosomatic or psychiatric disorders an attempt was made to restore their mental health by stimulation of one of the sensory systems. Fragrance (citrus was our choice) which comforts through stimulation of the olfactory system was applied to depressive patients. It was given to 12 depressive subjects and the results indicated that the doses of antidepressants necessary for the treatment of depression could be markedly reduced. The treatment with citrus fragrance normalized neuroendocrine hormone levels and immune function and was rather more effective than antidepressants.

Automated enzymatic measurement of adenosine deaminase isoenzyme activities in serum.

We developed a simple, rapid, and automated method for simultaneous measurement of adenosine deaminase (ADA, EC 3.5.4.4) isoenzymes in human serum, based on their apparent difference in Ki values for erythro-9-(2-hydroxy-3-nonyl)adenine (EHNA) as inhibitor. Serum ADA was partially purified by CM-Sephadex, gel-filtration, and affinity chromatography into two types of isoenzymes, designated ADA1 (300 kDa) and ADA2 (120 kDa). Because ADA2 has a higher Km for adenosine and higher Ki values for EHNA than does ADA1, the activity of ADA1 is almost completely inhibited by EHNA at 0.1 mM (analytical recovery 4.1%), whereas ADA2 is practically unaffected (analytical recovery 94.8%) by that concentration of EHNA. We measured the activities of ADA2 and total ADA in the presence and absence of 0.1 mM EHNA. ADA1 activities were calculated by subtracting the activity of ADA2 from that of total ADA. The mean within-assay CV was 5.7% for ADA1 and 2.7% for ADA2. The interassay CV was 2.8% for ADA1 and 3.1% for ADA2. Results of the present method correlated well (r = 0.9026 for ADA1, 0.9438 for ADA2) with those of the ion-exchange chromatography method. The upper limits of the reference intervals, as calculated from data for 320 healthy donors, are 7.2 U/liter for ADA1, and 14.6 U/liter for ADA2. This method is suitable for analysis of large numbers of samples in clinical laboratories for routine monitoring of the activities of ADA isoenzymes in serum.

NOREPINEPHRINE INHIBITS HUMAN NATURAL KILLER CELL ACTIVITY IN VITRO

The effect of norepinephrine on human NK cell activity was investigated using a flow cytometry assay. NK cell activity was found to be inhibited by direct addition of norepinephrine to lymphocyte/target cell mixtures in a dose-dependent fashion. This inhibitory effect of norepinephrine was blocked by propranolol but not by atenolol. The results suggest that norepinephrine has a negative influence on NK cell activity and that the effect of norepinephrine is mediated via beta 2-adrenoceptors.

Healthy HTLV-I carriers in Japan: the haematological and immunological characteristics

Summary. The haematological and immunological characteristics of 34 healthy anti‐HTLV‐I antibody‐positive individuals (HTLV‐I carriers) in southwestern Japan were examined. No significant difference was noted between carriers and the controls in counts of RBC, WBC and the absolute number of lymphocytes. The serum IgG in the carriers was higher than that of the controls. The percentages of OKT4, OKT8, OKIal and Bl‐positive cells were found to be normal in the peripheral blood of the carriers, whereas the percentages of OKT11 and anti‐Tac‐positive cells were significantly higher in the carriers than in the controls. A correlation was observed between the percentages of anti‐Tac‐positive cells and the titres of anti‐HTLV‐I antibody in the carriers. After a 72 h incubation of peripheral blood lymphocytes with medium alone, the percentage of anti‐Tac‐positive cells tended to decrease in the controls, but to increase in carriers, with the appearance of large blastoid cells resembling blastic transformed lymphocytes cultured with mitogen. Tac and la antigens were markedly expressed on these large blastoid cells.

Signaling from LFA-1 contributes signal transduction through CD2 alternative pathway in T cell activation

LFA-1, a member of the integrin family of molecules, is involved in mediating cellular adhesion in all phases of the immune response, playing a role in the interaction of helper T cells as well as in killing of target cells by both cytotoxic T cells and natural killer cells. We have developed a monoclonal antibody, anti-HVS6B6, which recognizes a functionally unique epitope of the LFA-1 molecule. Although this mAb itself was not mitogenic against T cells, it induced a strong proliferative response when added to T cells with submitogenic concentrations of anti-CD2 (anti-T11(2) and anti-T11(3)) mAbs. In contrast, other anti-LFA-1 mAbs (CD11a and CD18) suppressed this anti-CD2 mAb-induced T cell proliferation. Kinetic studies showed that anti-HVS6B6 acts on an early event in CD2-mediated T cell activation. Although T11(3)-epitope expression induced by anti-T11(2) mAb was not affected by treatment of cells with anti-HVS6B6, both Ca2+ influx and phosphatidylinositol turnover induced by anti-CD2 mAbs were markedly enhanced by the pretreatment of T cells with anti-HVS6B6 mAb. These results indicate that the LFA-1 mediating signal contributes to a very early phase of signal transduction during CD2-mediated T cell activation.

The Mechanisms of Immune Suppression by High‐pressure Stress in Mice

The effects of high‐pressure stress on the induction of anti‐sheep red blood cells (SRBC) and of plaque‐forming cells (PFC), and on thymus weight, were studied in BALB/c mice in‐vivo and in‐vitro.

Differentiation-associated carbohydrate chain on human hematopoietic cells recognized by Clerodendron trichotomum lectin

In the screening of hematopoietic cell line cell aggregations, the extract of Clerodendron trichotomum seed was found to aggregate K-562 and KG-1 specifically. In the flow cytometric analysis using FITC-conjugated purified CTL, it was confirmed that CTL recognizes the specific carbohydrate(s) which seem to appear only in the early stages of differentiation of myeloid (KG-1) and erythroid (K-562) cell line cells and erythrocytes. The CTL binding to K-562 cells was decreased by TPA treatment which is known to induce retrodifferentiation of K-562. It is also found that this carbohydrate(s) were shaded with NANA on the differentiated cells. In the erythrocyte, CTL receptor was partially shaded by NANA.

Inhibitory Effect of Free Radical Scavengers on Cyclic Flow Variations in Unsedated Dogs with Coronary Stenosis and Endothelial Injury

Severe coronary artery stenosis with endothelial injury in the canine model induces cyclic coronary flow variations (CFVs), which are partially due to spontaneous platelet aggregation and dislodgement at the stenotic site. In the present study, we used anesthetized open-chest and unsedated closed-chest dogs with CFVs to investigate whether oxidative metabolic burst (hydrogen peroxide generation) occurred in neutrophils during CFVs and whether CFVs were attenuated by superoxide dismutase (SOD) and catalase. CFVs were produced by placing a cylindrical constrictor on the left anterior descending coronary artery (LAD). LAD blood flow was monitored by means of a Doppler flow probe placed proximally to the constrictor, and the severity of CFVs was expressed by both the frequency of CFVs and mean LAD blood flow. Hydrogen peroxide generation in neutrophils was measured by flow cytometry, using single cell analysis, and was expressed as the mean fluorescence intensity of 2’, 7’-dichlorofluorescein. Dogs received an intravenous infusion of saline (n = 8), SOD (5 mg/kg, n = 7), catalase (5mg/kg, n = 7), or a combination of SOD and catalase (same doses, n = 7). Although the mean fluorescence intensity did not change in sham-operated dogs without CFVs (61.7 ± 15.8 to 60.4 ± 11.8; NS), the intensity in the dogs with CFVs was significantly increased during CFVs (62.2 ± 13.7 to 79.8 ± 9.8; P < 0.005). These results indicate that hydrogen peroxide is generated in neutrophils.

Purine metabolic enzymes in sera of healthy HTLV-1 carriers.

The purine metabolic enzymes; adenosine deaminase (ADA) and purine nucleoside phosphorylase (PNP) are known to be associated with lymphocyte differentiation. ADA isoenzyme (ADA1 and ADA2) and PNP activities were assayed in the sera of 22 healthy carriers with positive for anti-HTLV-1 antibody and 20 normal individuals. The results revealed that both ADA2 and PNP activities were significantly elevated in sera of healthy carriers (p<0.001) as compared with normal controls. No significant difference in ADA1 activity was noted in the two groups. These data imply that ADA2 serum level is more likely to reflect the condition of peripheral T lymphocytes than that of total ADA activity. Measurement of these enzyme activities in serum may be a useful parameter of diagnosis in human T-cell leukemia/lymphoma virus-1 infection.

Expression Profiles of T Cell Associated Antigens on Adult T Cell Leukemia Cells: Results of a Workshop Study

Adult T cell leukemia (ATL) is one of the T cell malignancies in man predominantly found in the Kyushu area in Southern Japan with characteristic clinical and hematologic features (1), and C-type retrovirus, isolated from the ATL cells, has recently been identified as the causative agent (2,3). Therefore, it has been of major interest to define leukemogenesis of mature T cells by ATL virus (ATLV). The Workshop presented an opportunity to study leukemia cells in ATL patients using its battery of monoclonal antibodies (mAbs) in a T cell protocol. Freshly obtained ATL cells can be used as a panel of cells possessing matured malignant T cell antigens on the cell surface (4) to evaluate the specific reaction of mAbs. Furthermore, the expression profile of T cell associated antigens on ATL cells could be well-characterized by the multiple sources of mAbs. A rarely observed subtype of ATL, with double markers (OKT4 and OKT8) present on the leukemic T cells, was also characterized phenotypically with the Workshop’s battery of mAbs.