PubMed Health⌕ Search

SEARCH · PubMed Health

Results for “Trained Immunity”

Explore indexed PubMed citations for clinical trials, systematic reviews and public health research. Read source abstracts and follow each citation to its original PubMed record.

Quote a phrase for an exact phrase match. Source license links do not imply unrestricted reuse.

At least 163 records · Page 9Linked to original sources
PubMed2005

Chronic resistance exercise training improves natural killer cell activity in older women.

BACKGROUND: Regular exercise has been reported to slow the age-associated declines in natural killer cell activity (NKCA). To evaluate this response, we recruited older, postmenopausal women (65-85 years old) to fill one of two groups: training (10 weeks of resistance exercise; TR) or control. METHODS: Blood samples were collected from an arm vein in the TR group at rest (PRE), immediately following (POST), and 2 hours (2H) following an acute bout of resistance exercise both before (BEFORE) and after (AFTER) training. Leukocytes and NKCA were determined by flow cytometry and a whole blood (51)Cr release assay, respectively. RESULTS: Acute exercise increased total leukocyte (p < .05), CD8 (p < .05), CD4 (p < .05), and CD56 counts (p < .05), but there was no effect of training. NKCA was greater TR-AFTER-PRE (136%), -POST (80%), and -2H (127%) compared to similar values from TR-BEFORE (p < .05). CONCLUSION: Increased resting NKCA after chronic resistance training suggests that immunity has been improved.

Aged↗
PubMed2001

History of respiratory illness at the U.S. Naval Academy.

Throughout history, respiratory diseases have been a frequent cause of morbidity in U.S. populations. Because of stress, crowding, and naïve immune systems, military training populations are particularly prone to acute respiratory disease epidemics. An examination of the history of respiratory illness at the U.S. Naval Academy revealed that, in the earliest decades at the school, respiratory illness was a primary cause of both disease and mortality. With the advent of antibiotics and vaccines, most respiratory disease mortality has been reduced. However, even today, morbidity remains significant. Health concerns regarding respiratory diseases are heightened by emerging and reemerging respiratory disease agents that have increased antibiotic resistance and/or increased virulence. Enhanced surveillance and rapid diagnostic capabilities, placed in military settings, will increase knowledge of the epidemiology of many respiratory diseases. These strategies can lead to earlier treatment and prevention measures, thus halting the further transmission of disease and decreasing both morbidity and mortality. During the most recent history of the Naval Academy, acute respiratory infections have remained a primary cause of medical morbidity.

History, 19th Century↗
PubMed1998

Autoantibody catalysis: no longer hostage to Occam's razor.

Autoantibody catalysis is now a well-established phenomenon, but the initial finding of autoantibody-catalyzed VIP cleavage was suspected to be an artefact by certain practitioners of designer antibody catalysis, mainly because of conceptual complexities not foreseen in our training about the immune system and about the mechanisms of biological catalysis. Confirmation that antibodies can acquire proteolytic activity by entirely natural means has emerged, ironically, in part from the field of designer catalytic antibodies. Recent studies have provided insight into the molecular strategies whereby antibodies can combine antigen binding with chemical catalysis, and the contributions of innate and adaptive immune mechanisms in the proteolytic activity. The history of this field illustrates the dangers of assuming that novel observations must fit into the simple confines of established theories. Scientific theories are changeable entities, dependent on empirical data and interpretations of the data, and their growth is better served by keeping an open mind.

Amino Acid Sequence↗
PubMed2003

Dairy products, meat and sports performance.

Creatine supplementation improves repetitive, short-term performance. It has not been shown that exclusion of meat from the diet would impair repetitive short-term performance. In contrast, reduction of protein intake and a concomitant increase of carbohydrate intake during a period of 3-5 days improves anaerobic (2-7 minutes) performance. The protein intake in a mixed or lacto-vegetarian diet is adequate even for elite athletes, providing that energy requirements are met. Many dietary supplements have been suggested to increase muscle mass and/or to decrease fat mass. Although the effects of conjugated linoleic acid on body composition in athletes are not clear, some positive findings in untrained, obese individuals call for more studies. Strenuous training may impair immune function and increase the susceptibility to infections. Exclusion of meat from the diet does not seem to have adverse effects on immune function. Glutamine supplementation (>3-6 g/day) may improve immune function, but more studies are needed. Similarly, more studies on the possible effects of whey protein and probiotic supplementation on immune function and performance in physically highly active individuals are warranted. Vitamin and mineral balance are not usually a problem among athletes. Notable exceptions may be calcium and iron in some females. Increased calcium intake in athletes with hormonal and menstrual disturbances could theoretically help in maintaining bone status; however, no data are available. A diet with meat may help in maintaining adequate iron stores.

Body Composition↗
PubMed1975

Current patterns of acute respiratory disease in the United States Navy and Marine Corps.

During 1974 there was an apparent decrease in the reported amount of acute respiratory illness in the Navy and Marine Corps. Streptococcal infections continued to be controlled by the selective use of prophylactic benzathine penicillin in recruit training centers. Influenza immunization limited the impact of that illness, and serogroup C polysaccharide vaccine reduced the amount of meningococcal disease among recruits. Although some of the data are contradictory there are indications that fully potent live adenovirus vaccines lessen the frequency and severity of respiratory illness in recruit populations. Continued epidemiologic study will be required to fill the gaps in our knowledge.

Acute Disease↗
PubMed2000

Immune function and incidence of infection during basic infantry training.

The effect of an 18.5-week infantry training program on health status was studied in 23 male military personnel (aged 22.0 +/- 0.5 years, mean +/- SE). Aerobic power, body composition, and immune function (including natural killer cell activity, mitogen-stimulated lymphocyte proliferation, in vivo cell-mediated immunity, and secretory immunoglobulin A levels) were measured in subjects at the beginning and end of the course. Subjects self-reported their symptoms of sickness in health logs using a precoded checklist. Data from this study indicate that subjects became leaner and maintained, but did not increase, their aerobic fitness by the end of the course. Cell function was enhanced significantly; however, in vivo cell-mediated immunity remained the same, and levels of secretory immunoglobulin A were lower by the end of the course. The incidence of infection remained stable throughout the course. These results indicate that the current pattern of infantry training does not have an adverse effect on the health status of recruits.

Adult↗
PubMedDate not supplied

[Portrait of the formation in vaccination training offered to Quebec nurses in the workplace].

INTRODUCTION: Nurses carry out essential functions in the area of immunization in Québec and their role has broadened considerably since January 2003, following legislative modifications. However, the training received may not always allow nurses to fill this role satisfactorily. This study seeks to document the training in immunization offered to Québec nurses in the workplace. METHOD: A questionnaire was mailed to the directors or heads of nursing care (DSI/RSI) in 477 health care establishments in Québec in March 2003. RESULTS: Health care establishments in Québec offer more training to nurses on the job (68%) than at the moment of hiring (43%). These percentages vary widely according to the type of establishment. More than 90% of the local community service centres (CLSC) that responded offer training to their nurses. The indications/contraindications of immunization products and emergencies related to vaccination represent the themes most frequently dealt with. Only 38% of respondents affirm that the nurses in their institution are "very favourable" to vaccination. DISCUSSION: Almost all Québec CLSCs, which is where most immunization activities are carried out, offer training in vaccination to their nurses. On the other hand, few hospital centres (CH) and long-term care establishments (CHSLD) do so. Further documentation should be carried out on the impact of less than optimal training on the promotion of immunization programs by nurses.

Attitude of Health Personnel↗
PubMed2003

Influence of carbohydrate ingestion on immune changes after 2 h of intensive resistance training.

Thirty strength-trained subjects were randomized to carbohydrate (CHO) or placebo (Pla) groups and lifted weights for 2 h (10 exercises, 4 sets each, 10 repetitions, with 2- to 3-min rest intervals). Subjects received 10 ml x kg(-1) x h(-1) CHO (6%) or Pla beverages during the weight training bout. Blood, saliva, and vastus lateralis muscle biopsy samples were collected before and after exercise. Blood cell counts were determined, and plasma was analyzed for IL-6, IL-10, IL-1 receptor antagonist (IL-1ra), IL-8, and cortisol. Muscle was analyzed for glycogen content and relative gene expression of 13 cytokines (IL-1alpha, IL-1beta, IL-2, IL-4, IL-5, IL-6, IL-8, IL-10, IL-12p35, IL-12p40, IL-15, IFN-gamma, TNF-alpha) by use of real-time quantitative RT-PCR. Significant but modest increases were measured for plasma IL-6, IL-10, IL-1ra, and IL-8, but the pattern of increase did not differ between CHO and Pla groups. The rate of decrease in muscle glycogen content did not differ between CHO and Pla (P = 0.463). Muscle cytokine mRNA was detected preexercise for IL-1beta, IL-6, IL-15, IL-8, and TNF-alpha, and of these, IL-1beta, IL-6, IL-8, and TNF-alpha were significantly increased after the 2-h weight training bout. The increase in mRNA (fold difference from preexercise) did not differ between CHO and Pla groups. In summary, CHO vs. Pla ingestion did not alter modest increases measured for plasma IL-6, IL-10, IL-1ra, and IL-8, and muscle gene expression for IL-1beta, IL-6, IL-8, and TNF-alpha in strength-trained subjects lifting weights intensively for 2 h.

Administration, Oral↗
PubMed1998

Dietary long-chain (n-3) fatty acids facilitate immune cell activation in sedentary, but not exercise-trained rats.

Dietary long-chain (n-3) fatty acids from fish oil and low intensity exercise have been reported, independently, to inhibit tumor growth in rats. The mechanism for these effects is not known but may be related to diet and exercise-induced alterations in immune function. To study the individual and combined effects of these interventions on anticancer immune responses, healthy Fischer 344 rats were fed, for 4 wk, one of two semi-purified diets (polyunsaturated to saturated fatty acid ratio = 0.9), which differed only in the composition of fat (200 g/kg) and provided long-chain (n-3) fatty acids at 0 or 33 g/kg of total fat. Rats were randomly assigned to groups in a 2 x 2 experimental design to swim 3 h/d or to remain sedentary. For sedentary rats, dietary (n-3) fatty acids increased (P < 0.05) splenic natural killer (NK) cell cytotoxicity and the percentage of activated (CD71+) T and B cells and macrophages in spleen after concanavalin A stimulation. For exercise-trained rats, feeding the high (n-3) diet decreased (P < 0.05) the percentage of CD71+ T helper and B cells after stimulation. NK cell cytotoxicity, and the percentages of CD71+ T cells, B cells and macrophages after stimulation in the high (n-3)-fed exercise-trained group were not different than those of the low (n-3)-fed sedentary group. Thus individually, but not in combination, long-chain (n-3) fatty acids and low intensity exercise may be advantageous by augmenting cell-mediated immune function and NK cell cytotoxicity in healthy rats.

Animals↗
PubMed1992

Immune responsiveness and risk of illness in U.S. Air Force Academy cadets during basic cadet training.

It has been proposed, but not confirmed, that environmental stressors alter immune function and increase the risk of viral infection among healthy individuals. We evaluated this hypothesis, examining the relationship among stress, immune function, and illness in 96 first-year U.S. Air Force Academy cadets during orientation and 4 weeks later during the stressful environment of Basic Cadet Training (BCT). Perceived stress and well-being levels of cadets were assessed via questionnaire. Immune responsiveness was analyzed by PHA-stimulated thymidine uptake in mononuclear leucocytes and by serologic evidence of reactivation of the Epstein-Barr virus (EBV). We documented significant declines in in vitro PHA-induced lymphocyte transformation (-35%; p less than 0.05) and subjective well-being (-19%; p less than 0.05) from orientation to BCT with corresponding, significant increases in perceived stress (+32%; p less than 0.05). Despite significantly altered in vitro immune responsiveness, there was no serologic evidence of EBV reactivation nor was there an association between these measures and risk of illness as determined by medical chart review and self-reported symptoms. These results suggest that reduced in vitro immune responsiveness during a moderate stressor may not necessarily lead to an increased risk of infection and/or reactivation of EBV in normal individuals.

Aerospace Medicine↗
PubMed1988

Effect of acute physical exercise on lymphocyte subpopulations in trained and untrained subjects.

To clarify the difference in immunity between untrained subjects and well-trained athletes, the number of total leukocytes (WBC), lymphocytes, and neutrophils, percentages of various lymphocyte subpopulations (OKT3, OKT4, OKT8, Leu7, OKla1), and the levels of lymphocyte transformation response to phytohemagglutinin (PHA) were determined in five untrained male subjects and six male athletes before, immediately after, and 24 and 72 h after acute physical exercise at 60% of VO2max for 2 h. Exercise produced a significant rise in the number of WBC, lymphocytes, and neutrophils in both groups. Immediately after exercise, the percentage of OKT3 or OKT4 positive cells had significantly decreased in both groups, whereas that of OKT8 positive cells had markedly increased only in the athletes. Neither group showed any change in the percentage of OKla1 positive cells. In both groups, the response of lymphocytes to PHA immediately after exercise was significantly lower than before, 24 h and 72 h after exercise. The level of Leu7 positive cells rose remarkably immediately after exercise in the athletes, but not significantly in the untrained subjects. These results suggest that an increase in Leu7 positive cells provides added host defense capacity in trained athletes during periods of stress which impair T-lymphocyte function.

Adolescent↗
PubMed2005

Randomized controlled trial of exercise and blood immune function in postmenopausal breast cancer survivors.

The objective was to determine the effects of exercise training on changes in blood immune function in postmenopausal breast cancer survivors. Fifty-three postmenopausal breast cancer survivors were randomly assigned to an exercise (n=25) or control group (n=28). The exercise group trained on cycle ergometers three times per week for 15 wk. The control group did not train. The primary end point was change in natural killer cell cytotoxic activity in isolated peripheral blood mononuclear cells. Secondary end points were changes in standard hematological variables, whole blood neutrophil function, the phenotypes of isolated mononuclear cells, estimations of unstimulated and phytohemaglutinin-stimulated mononuclear cell function (rate of [3H]thymidine uptake), and the production of proinflammatory [interleukin (IL)-1alpha, tumor necrosis factor-alpha, IL-6] and anti-inflammatory cytokines (IL-4, IL-10, transforming growth factor-beta1). Statistical tests were two-sided (alpha <0.05). Fifty-two participants completed the trial. Intention-to-treat analyses, which included the baseline value as a covariate, showed significant differences between groups for change in percent specific lysis of a target natural killer cell at all five effector-to-target ratios (adjusted mean between-group change over all 5 effector-to-target ratios = +6.34%; P <0.05 for all comparisons), the lytic activity per cell (adjusted mean between-group change = -2.72 lytic units; P=0.035), and unstimulated [3H]thymidine uptake by peripheral blood lymphocytes (adjusted mean between-group change = +218 per dpm x 10(6) cells; P = 0.007). There were no significant differences between groups for change in any other end point. Exercise training increased natural killer cell cytotoxic activity and unstimulated [3H]thymidine uptake by peripheral blood lymphocytes in postmenopausal breast cancer survivors.

Breast Neoplasms↗
PubMed1983

Cross-stressor immunization against the behavioral deficits introduced by uncontrollable shock.

Exposure to inescapable shock disrupted performance in both shock- and water-escape tasks. These deficits were prevented in mice that were previously trained in the same task. However, an asymmetrical immunization effect was seen in a cross-stressor paradigm. Whereas deficits of water-escape performance engendered by inescapable shock were prevented by prior shock-escape training, the deficits of shock-escape performance were not eliminated by prior water-escape training. Evidently, the immunization effect occurs when initial training and subsequent testing are conducted in the same task, or when the initial training and uncontrollable stress session involve the same aversive stimulus. Norepinephrine determinations revealed that reductions of the amine introduced by inescapable shock were unaffected by prior shock-escape training and were enhanced by prior exposure to the stress of water immersion. Thus, although the performance deficit introduced by inescapable shock may be related to variations of norepinephrine, the immunization effect probably was unrelated to alterations of this transmitter. Rather, the data provisionally suggested that the immunization stems from two independent factors: Namely, initially training animals in an active escape task may (a) disrupt subsequent learning that the inescapable stress actually is uncontrollable and (b) limit the influence of the motor deficits introduced by uncontrollable shock on subsequent escape performance.

Animals↗
PubMed2003

Microarray technology--the future analyses tool in exercise physiology?

Microarray analysis offers a set of analytical platforms that provide rapid, affordable and substantial information at the DNA, RNA or protein level. It enables the analysis of thousands of genes simultaneously in a parallel manner across samples derived from various biological sources and treatment regimens. This development became possible as a result of the combination of three technological advances achieved at the beginning of the 1990's, namely parallelism, miniaturization and automation. In regular physical checkups the microarray technology could be used to supplement the current spectrum of tests and therefore enhance the quality of the data obtained. Arrays for analyses of RNA expression will allow gene expression profiling also in exercise physiology. DNA chips may also be used for genetic screening and diagnostics to analyze polymorphisms and mutations which may underlie genetic diseases or interindividual variations between subjects. Using microarrays in exercise physiology will provide new insights into the complex molecular mechanisms of the exercise-induced stress response, adaptation to training and modulation of immune function. Gene expression profiling and genetic screening will probably help to characterize and predict the individually variable response to and efficiency of training.

Exercise↗
PubMed1996

Effects of anaerobic exercise on the immune system in eight- to seventeen-year-old trained and untrained boys.

OBJECTIVES: To determine the immunologic response to a brief bout of intense exercise in children and to determine the effects of prolonged activity and maturation level of the subjects on this response. STUDY DESIGN: We determined counts of leukocytes and their subsets, counts of lymphocytes and their subsets, and natural killer (NK) cell activity and cell number before and 3 and 60 minutes after a Wingate anaerobic test (WAnT) in 16 male swimmers (9 to 17 years of age) and 17 male nonswimmers (9 to 17 years of age). Subjects were also categorized by pubertal status based on Tanner staging and by level of physical activity. The Student t test and analysis of variance were used to determine statistical significance, with values expressed as mean +/- SEM. RESULTS: Three minutes after the WAnT, all children had increases in leukocytes (28%), lymphocytes (43%), and NK cells (395%) (p < 0.01). Swimmers had less baseline NK cell activity (54 +/- 6 cytolytic units) than nonswimmers (87 +/- 10 cytolytic units) after the WAnT (p < 0.01), although both groups showed an increase to similar levels of NK activity 3 minutes after exercise. Pubertal effects on these responses were not significant. CONCLUSIONS: Our results demonstrate transient leukocytosis, lymphocytosis, and increases in NK cell number and activity in 8- to 17-year-old boys after a brief bout of intense exercise. Formal athletic training appears to be associated with a lower baseline NK cell activity, and yet such activity is still within the normal range for this age group. Further investigations are necessary to determine the impact of such training on overall health and the ability to fight infection.

Adolescent↗
PubMed1989

[The effect of exercise and elite athletics on the immune system].

Physical and psychological stress influence immune responses. The influence of physical stress on immunity is through the action of neuro-peptides and other hormones and by way of a direct effect on the cells controlling the immune response. There is little or no evidence that physical activity, i.e. regular exercise without competition has any harmful effects on immunity. On the contrary, some animal studies tend to indicate a beneficial effect of exercise on the immune system. Regular intense training and competitions have been associated with increased morbidity, especially from infections. This may be connected to suppression of cell-mediated and humoral immunity which has been demonstrated in connection with exercising to exhaustion.

Animals↗