Phagocytic function in cyclists: correlation with catecholamines and cortisol.

Flow cytometer measurements were made of the basal variations in peripheral blood functional monocytes and granulocytes over the course of a training season (January to November) of a cycling team. Parallel determinations were made of plasma concentration of catecholamines (chromatography) and cortisol (RIA) in a search for neuroendocrine markers. The results showed the greatest phagocytic capacity to occur in the central months (March, May, and July), coinciding with the greatest number and highest level of competitive events with good correlation with a peak in epinephrine during these months (r(2) = 0.998 for monocytes and r(2) = 0.674 for granulocytes). No good correlations were found between phagocytosis and norepinephrine or cortisol. The highest values for phagocytosis and epinephrine concentration were found in May. These results suggest that blood epinephrine concentration could be a good neuroendocrine marker of sportspeople's phagocytic response.

Functional activity of immune cells in female MS-patients.

Since the well documented immunological disturbances in patients suffering from multiple sclerosis are especially attributed to T-cells we felt it expedient to look also for the functional activity of lymphocytes, monocytes, granulocytes and natural killer cells in the peripheral blood of female MS-patients (n = 17) and healthy controls (n = 17). While MS-patients showed decreased levels of total lymphocytes, CD2(+)- and CD8(+)-cells the percentage of HLA-DR(+)-monocytes was increased, indicating a high activity level of these immune cells, whereas we could find no differences in the functional tests of monocytes, granulocytes and natural killer cells between MS-patients and healthy controls. The percentage of HLA-DR(+)-T-lymphocytes increased with the duration of the illness and support the stronger consideration of clinical staging.

Exercise, cancer and the immune response of monocytes.

We examined the influence of a regularly moderate endurance training program on qualitative and quantitative alterations of monocytes from 24 breast cancer patients. At the beginning, after 5 weeks and 7 months of bicycle training we analyzed the composition of leucocytes and phagocytotic activity of monocytes using two different methods under resting conditions. At the end of the study the amount of granulocytes was enhanced, but lymphocytes and monocytes were decreased. While the phagocytotic capacity of monocytes increased compared with receptor destroying enzyme-treated sheep red blood cells, phagocytosis against Anti D-loaded human erythrocytes did not change. These different results led us to suggest that physical exercise training increases the number of specific receptors in the surface membrane of monocytes.

Influence of a moderate exercise training on natural killer cytotoxicity and personality traits in cancer patients.

We have investigated the influence of exercise training on natural killer cells and psychological behaviour in cancer patients. 24 women with carcinomas of the breast performed a moderate training program two to three times a week for seven months. At the beginning, after five weeks and at the end of the study we analyzed the amount and the activity of natural killer cells (CD 56) under resting conditions. Personality traits were measured with the FPI-R questionnaire at the same time points. While the amount of natural killer cells did not change, their cytotoxic activity was increased at the end of the study. Furthermore, the discomfort decreased. After 5 weeks satisfaction of life was enhanced and at the end of the investigation we observed a strict connection of this improvement with the frequency of exercise. These results demonstrate a stimulating influence of moderate exercise training on the resting NK-cell activity even in cancer patients.

Role of Acetylsalicylic Acid in Cytokine Stimulation of Macrophages in Antibody-Dependent Cellular Cytotoxicity (ADCC).

In addition to the spectrum of biological action already known to be exhibited by acetylsalicylic acid (ASA) as an analgesic, anti-inflammatory and platelet aggregation inhibitor, there is growing evidence of a stimulatory effect on the immune system. ASA has been found to increase the production ofcytokines and to increase the activity of various leukocytes. The action of ASA on the activity of mouse peritoneal macrophages was therefore investigated in the present study. Therapeutically effective concentrations of ASA, which are known to decrease levels of prostaglandins, had neither a stimulating nor an inhibiting influence on antibody-dependent cellular cytotoxicity (ADCC) or on the binding capacity of macrophages with regard to SW 948 tumour cells. Likewise ASA had little or no adverse effect on the capacity of the macrophages for stimulation by interferon-gamma (IFN-gamma) and interleukin-4 (IL-4). Taken together, the immunostimulant effect of ASA shown in the literature as an increased production of interleukin-2 (IL-2) and IFN, could not be confirmed on the basis of the macrophage cytotoxiclty.

Acetylsalicylic acid has no effects on various isolated immune cells in vitro.

In addition to the well known biological effects of acetylsalicylic acid (ASA), its stimulating effect on the immune system has recently been described. In the present study, therefore, the influence of ASA on isolated leucocytes was investigated in vitro. Various concentrations of ASA, representing therapeutic concentrations, had neither an inhibitory nor a stimulating influence on the cytotoxicity of CD16-positive cells. The phytohaemagglutinin-induced proliferation of lymphocytes and the phagocytosis activity of monocytes and neutrophilic granulocytes was similarly unaffected. These results would indicate that the immunostimulating effects already described for ASA cannot be examined in isolated leucocytes in vitro and should be attributed to an interaction of various effector cells in vivo.

Influence of acetylsalicylic acid on antibody-dependent cellular cytotoxicity (ADCC) of peritoneal macrophages.

Very recent evidence indicates that, in addition to its already known analgesic, anti-inflammatory, antipyretic, and platelet-aggregation-inhibiting properties, acetylsalicylic acid (ASA) exerts a positive influence on the immune system. Therefore, its action on murine peritoneal macrophages was investigated in the present study. Various ASA concentrations (50-200 micrograms/ml) failed to have any stimulating or inhibiting effect on antibody-dependent cellular cytotoxicity (ADCC) and on the binding capacity of macrophages from various levels of activation against SW 707 tumor cells. Furthermore, no time dependence of the stimulation was observed over a period of up to 48 hrs. These results suggest that the reported positive effect of ASA on the immune system, manifested by increased production of interleukins and interferon, is due to an interaction of macrophages and lymphocytes and not to a direct increase in macrophage activity.

Physical exercise may improve macrophage phagocytic activity of tumor bearing mice.

The influence of an endurance training on the phagocytic activity of macrophages from tumor bearing mice was studied. Female NMRI mice were trained on a treadmill. The training period differed from 3 to 6 weeks for different experimental groups and was performed either before or after tumor inoculation, or both. Either L-1210 or S-180 tumor cells were inoculated into the peritoneal cavity or the interscapular region, respectively. The phagocytic activity of peritoneal and spleen macrophages was estimated at different intervals. The trained animals' macrophages showed increased phagocytic activity especially evident in the group that had been trained before and after tumor inoculation. It was concluded that physical exercise might enhance phagocytosis of macrophages in tumor bearing animals and that this effect strongly depends on the duration and onset of the training program.

Cytokine stimulation of antibody-dependent cellular cytotoxicity (ADCC) enhances cytolytic but not binding capacity of peritoneal macrophages.

Macrophages in varying states of activation differ in their ability to perform antibody-dependent cellular cytotoxicity (ADCC). To define further the activation requirements for macrophages to perform cytolytic functions, we stimulated peptone-elicited peritoneal macrophages, which exhibit only a low level of ADCC, with a panel of cytokines and then assayed for the macrophages capacity to effect the rapid and slow forms of ADCC, to bind antibody-coated tumor cells, and to secrete H2O2 in response to immune complex or PMA. All four cytokine preparations, at optimal conditions, enhanced both forms of ADCC, but did not appreciably increase tumor cell binding. Three of the four cytokine preparations (Il-4, TNF and IFN-alpha/beta), however, increased the macrophages capacity to secrete H2O2 in response to either immune complex or PMA, IFN-gamma alone did not affect H2O2 secretion.

Potentiation of cytostatic but not cytolytic activity of murine macrophages after running stress.

The influence of physical exercise on the tumortoxicity of peritoneal murine macrophages (PMM) was investigated. The tumortoxic activity was discriminated into cytostatic and cytolytic effects. Cytostatic activity of PMM on tumor cells in vitro was studied using the proliferation assay of S-180 sarcoma cells. Cytolytic activity was monitored using the method of the slow form of antibody-dependent cellular cytotoxicity (ADCC) on SW 707 tumor cells. After a single exhaustive running session an increased cytostatic activity of PMM was observed as compared to PMM of sedentary animals. In PMM mediated ADCC no difference was detected between trained and untrained animals. It is concluded that physical exercise is a complex stimulus for macrophages that, at least in parts, triggers their cytotoxic activity against tumor cells.

Human macrophage function and physical exercise: phagocytic and histochemical studies.

Macrophages derived from human connective tissue were assayed for their enzyme content and phagocytic activity after physical exercise. A single exhaustive endurance-running test caused increased phagocytic and enzymatic activities of the macrophages. Thus, an exercise challenge activates the functional status of the cells. This effect of physical exercise on macrophages is inconsistent with the practical experience that high performance athletes suffer more frequently from harmless infectious diseases.

The influence of physical exercise on peritoneal macrophage functions: histochemical and phagocytic studies.

Peritoneal murine macrophages were assayed for their enzyme content and phagocytic activity after physical exercise. An endurance training as well as a single exhaustive exercise bout caused increased enzyme and phagocytic activities. However, a homogeneous activation could not be observed. The exhaustively exercised animals delivered macrophages with the highest levels of activation. Therefore, physical exercise has to be listed among the stimuli with macrophage-activating function. The inconsistency between an activating effect of physical exercise on macrophages and the observation that high-performance athletes suffer more frequently from harmless infectious diseases is discussed.