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PubMedDate not supplied

Impaired immune function in a premature infant with zinc deficiency after total parenteral nutrition.

The report describes a premature infant with necrotizing enterocolitis who developed symptoms of zinc (Zn) deficiency after three to four weeks of total parenteral nutrition (TPN). Clinical presentations included characteristic skin rash, alopecia, retarded growth, generalized edema and decreased serum alkaline phosphatase (ALP). Immune function studies revealed impaired neutrophil adhesion and mitogen-induced lymphoproliferation, whereas phagocytosis, chemotaxis and lymphocyte subsets remained normal. A high dose of elemental Zn (2.5 mg/kg/day), administered orally, improved the clinical symptoms and restored the immune function. In patients with Zn deficiency, impaired neutrophil adhesion and lymphocyte function may contribute to immunodeficiency which can be reversed with adequate Zn supplementation.

Humans↗
PubMedDate not supplied

Immune function in adult highland Papua New Guinea patients with pneumonia.

Immune function and nutritional indices were studied in adult highland Papua New Guinea (PNG) patients with pneumonia, PNG highland controls and expatriate controls living in the Papua New Guinea highlands. Compared to PNG controls, pneumonia patients had higher serum immunoglobulin (Ig)G concentrations, higher salivary IgA:albumin ratios, lower total body weights and a haematological pattern suggesting iron deficiency. PNG controls and pneumonia patients had fewer circulating CD4 and CD8 T lymphocytes than expatriate controls. The proportion of lymphocytes carrying neither T nor B cell markers was higher in PNG subjects than in expatriate controls. These observations indicate that PNG adult pneumonia patients are a distinguishable subpopulation of PNG adults who may be more susceptible than the general population to pneumonia. Decreased circulating T lymphocyte numbers may be, or reflect, a separate risk factor for the entire population.

Adult↗
PubMed1998

Immune function in healthy adolescents.

In the present study, we examine immunological functioning in normal healthy African-American and Latino/Latina adolescents recruited from an inner-city high school and an inner-city clinic. A battery of tests was performed with enumerative and functional measures which encompassed both innate and adaptive immunity. We found immune differences related to age, gender, and race on both the enumerative and the functional immune measures. This data expands the available body of information concerning normal immunity in healthy adolescents.

Adolescent↗
PubMed1984

Influence of nutritional status on immune functions in patients with Crohn's disease.

Nutritional status and immune function were correlated with clinical features in 56 patients with Crohn's disease. These were divided arbitrarily into either undernourished or well nourished groups according to whether their midarm circumference was below or above 90% of ideal standard. Results were also compared with 33 patients with ulcerative colitis and 28 normal subjects. Undernourished patients with Crohn's disease had significantly reduced total lymphocyte and T lymphocyte counts and a reduced proportion of monocytes that ingested latex particles. Well nourished patients with Crohn's disease were similar to the two control groups. Twenty one undernourished patients with Crohn's disease were also followed during the course of two to four months' nutritional treatment with an enteral supplement. Nutritional therapy was associated with significant anthropometric gains as well as significant rises in total lymphocyte and T lymphocyte counts. Serum orosomucoids were significantly higher in undernourished patients and decreased significantly during nutritional therapy. The results show that undernutrition and disease acuity may be associated with reduced immunological competence in patients with Crohn's disease, but all these measurements can be improved by short term nutritional treatment.

Adult↗
PubMed1999

Immune function and phenotype before and after highly active antiretroviral therapy.

Immune functions represented by equal CD4 counts before and after highly active antiretroviral therapy (i.e., pre- and post-HAART) in the same HIV-infected patients, were examined. Twelve HIV-infected patients were included. Patients had equal CD4 counts pre- and post-HAART and were studied on average 30 months pre-HAART and 17 months post-HAART. Post-HAART, CD8+ T cells expressed greater amounts of CD28 (p < .02), smaller amounts of CD38 (p < .02), and a reduced proportion of CD4+CD28+ T cells expressed CD38+ (p < .01). Proliferation increased (p < 10) in lymphocyte cell cultures stimulated with pokeweed mitogens or Candida, and was correlated to expression of CD28 on T cells (p < .02). The proportion of CD3-CD16-CD56+ natural killer (NK) cells increased (p < .05) and CD3-CD16+CD56- NK cells declined (p < .01). Production of interferon-gamma increased (p < .10). The number of naive and memory T cells, the non-major histocompatibility complex (non-MHC)-restricted and HIV-specific MHC-restricted cytotoxicity and the production of macrophage inflammatory protein-1gamma were unchanged. The finding of increased expression of CD28, correlating to increased proliferation capacity, and diminished expression of CD38 on T cells, indicates that following long-term HAART, repopulation occurs with less activated cells with increased proliferative capacity. This finding may be of clinical importance in considering risk and vulnerability for progression of opportunistic infections post-HAART.

Anti-HIV Agents↗
PubMed1998

Glutamine, exercise and immune function. Links and possible mechanisms.

Glutamine is the most abundant free amino acid in human muscle and plasma and is utilised at high rates by rapidly dividing cells, including leucocytes, to provide energy and optimal conditions for nucleotide biosynthesis. As such, it is considered to be essential for proper immune function. During various catabolic states including surgical trauma, infection, starvation and prolonged exercise, glutamine homeostasis is placed under stress. Falls in the plasma glutamine level (normal range 500 to 750 mumol/L after an overnight fast) have been reported following endurance events and prolonged exercise. These levels remain unchanged or temporarily elevated after short term, high intensity exercise. Plasma glutamine has also been reported to fall in patients with untreated diabetes mellitus, in diet-induced metabolic acidosis and in the recovery period following high intensity intermittent exercise. Common factors among all these stress states are rises in the plasma concentrations of cortisol and glucagon and an increased tissue requirement for glutamine for gluconeogenesis. It is suggested that increased gluconeogenesis and associated increases in hepatic, gut and renal glutamine uptake account for the depletion of plasma glutamine in catabolic stress states, including prolonged exercise. The short term effects of exercise on the plasma glutamine level may be cumulative, since heavy training has been shown to result in low plasma glutamine levels (< 500 mumol/L) requiring long periods of recovery. Furthermore, athletes experiencing discomfort from the overtraining syndrome exhibit lower resting levels of plasma glutamine than active healthy controls. Therefore, physical activity directly affects the availability of glutamine to the leucocytes and thus may influence immune function. The utility of plasma glutamine level as a marker of overtraining has recently been highlighted, but a consensus has not yet been reached concerning the best method of determining the level. Since injury, infection, nutritional status and acute exercise can all influence plasma glutamine level, these factors must be controlled and/or taken into consideration if plasma glutamine is to prove a useful marker of impending overtraining.

Animals↗
PubMed1994

Photoperiodic effects on tumor development and immune function.

Seasonal changes in adaptations associated with winter coping strategies have been frequently studied. Central among the suite of energy-saving, winter-coping strategies is the suspension of reproductive activities. The inhibition of reproduction by nontropical rodents is mediated by daylength changes. Although balanced annual energy budgets are critical, survival and subsequent reproductive success also require avoiding predators, illness, and early death. Because the stressors of winter could lead to suppressed immune function, we hypothesized that animals should have evolved survival strategies involving immunoenhancement. Short daylengths provide a predictive cue to individuals that could be used to enhance immune function in advance of stress-induced immunosuppression. In Experiment 1, adult female deer mice (Peromyscus maniculatus) were housed in either long (LD 16:8) or short (LD 8:16) days for 8 weeks, then injected with the chemical carcinogen 9,10-dimethyl-1,2-benzanthracene (DMBA) dissolved in dimethyl sulfoxide (DMSO) or with the DMSO vehicle alone. Animals were evaluated weekly for 8 weeks after injection. None of the animals treated with DMSO developed tumors in any of the experiments. Nearly 90% of the long-day deer mice injected with DMBA developed squamous cell carcinoma. None of the short-day deer mice injected with DMBA developed tumors. Small lesions developed at the site of injection; short-day females had less severe lesions and healed faster than long-day females. Immunoglobulin G (IgG) response to i.p. injection of sheep red blood cells (SRBC) did not differ photoperiodic conditions. The role of estrogens in the photoperiodic responses was evaluated in Experiment 2: Ovariectomized or sham-ovariectomized deer mice received estradiol benzoate replacement therapy or a control procedure in long daylengths for 8 weeks prior to injection of DMBA or DMSO, then were monitored for 8 additional weeks. Females treated with DMBA developed tumors at the same rate, regardless of estrogen manipulation. Estrogen did not affect healing rates. In Experiment 3, female deer mice were injected with a slurry of microspheres that either contained bromocriptine or were empty. Suppression of prolactin with bromocriptine resulted in a decrease of tumor incidence from 55.6% to 24% in long-day females 8 weeks after injection with DMBA. Healing rates were not affected by prolactin manipulations. Silastic capsules that were filled with either melatonin or cholesterol were implanted into long-day female deer mice in Experiment 4; 8 weeks later, females received an injection of either DMBA or DMSO, then were monitored for 8 weeks.(ABSTRACT TRUNCATED AT 400 WORDS)

9,10-Dimethyl-1,2-benzanthracene↗
PubMedDate not supplied

Effects of soman on neuroendocrine and immune function.

We have previously reported that plasma growth hormone (GH) and prolactin levels were markedly decreased in rats two weeks following a single dose (100 micrograms/kg, SC) of soman. We have now conducted additional experiments to attempt to determine whether neuroendocrine responses to physiological or pharmacological challenge are altered in rat survivors of soman exposure, and whether immune function, which can be affected by circulating hormones, is altered in the soman-exposed rats. In the present study, basal prolactin levels were not significantly lower in the soman-treated rats although prolactin increases in response to physiological or pharmacological challenge were attenuated. Also, basal growth hormone levels in soman survivors were similar to control levels in 2 of 3 experiments in the present report. In the third experiment, growth hormone levels were lower in soman-treated animals. Endocrine abnormalities appeared to be related to the severity of soman insult as assessed by changes in body weight following exposure. Both ACTH and prolactin responses to stress were impaired in a severely affected subpopulation of soman survivors. The thymus, an important immune organ, was decreased in weight in severely affected soman survivors, but other tests of immune function did not show differences between control and soman-exposed rats.

Adrenocorticotropic Hormone↗
PubMed1987

Analysis of Epstein-Barr virus-specific and non-specific immune functions in a patient during the development of a non-Hodgkin's lymphoma.

A 57-year-old woman who presented with a reactive non-malignant lymphadenopathy was observed subsequently during the development of a nodular centroblastic non-Hodgkin's B-cell lymphoma. The Epstein-Barr virus (EBV)-specific antibody profile and EBV-specific and non-specific cell-mediated immune functions were determined at first presentation, and at various times during progression, in order to determine whether EBV was causally involved in the lymphoma and to assess in general the patient's cell-mediated immune function. At presentation, an immunodeficient status was suggested by an EBV-specific antibody profile indicative of an activated persistent infection; high antibody titers to viral capsid antigen (VCA) and early antigens (EA), but a low level of antibodies to EBV nuclear antigen (EBNA) confirmed by lack of leukocyte migration inhibition in response to EBNA (LMI-EBNA). The number of positive cells reactive with OKIa1 monoclonal antibody was significantly depressed, as was also the natural and interferon-activated killing (NK-IAK). After emergence of the lymphoma, NK-IAK reactivity and spontaneous lymphocyte DNA synthesis augmented in parallel with an increase in the frequency of Leu-7+ blood lymphocytes. The EBV-specific cell-mediated response, reflected by the outgrowth inhibition (OI) test was abolished in parallel with a decrease in the frequency of OKT3- and OKT4-positive lymphocytes.

Cell Migration Inhibition↗
PubMed1998

Effect of zinc supplementation on the morbidity, immune function, and growth of low-birth-weight, full-term infants in northeast Brazil.

In Brazil, the highest incidence of low birth weight (LBW) occurs in the northeast, and diarrhea and respiratory infections are the main causes of infant mortality and morbidity. We hypothesized that LBW infants may be zinc deficient, and that this might be adversely affecting their immune function, morbidity, and postnatal growth. We therefore examined the effect of zinc supplementation on these outcomes during the first 6 mo of life. LBW full-term infants (mean birth weight 2337 g) were given daily for 8 wk either 5 mg Zn (n = 71), 1 mg Zn (n = 68), or a placebo (n = 66). Morbidity was determined prospectively through daily home visits (except on Sunday) during weeks 0-8, then twice weekly in weeks 9-26. Anthropometric measurements were made at 0, 4, 8, 17, and 26 wk. Immune function was assessed at 8 wk by the phytohemagglutinin skin test. Supplementation (5 mg Zn) was associated with a 28% reduction in diarrhea prevalence over the 6-mo period [after adjustment for confounders (P = 0.043)], and a 33% reduction in the prevalence of cough (NS, adjusted prevalence P = 0.073). All infants had a positive immune response at 8 wk. Although supplementation had no significant effect on weight and length gains from 0 to 26 wk, infants given 5 mg Zn gained more weight than infants given placebo during weeks 17-26 (P = 0.024, analysis of variance). There was no effect on any outcome with 1 mg Zn. We conclude that 5 mg Zn/d is of benefit to LBW, full-term infants who only have a modest weight deficit.

Cough↗
PubMed1993

Effects of retroviral infections on immune function in African-American intravenous drug users.

OBJECTIVES: To determine the effect of retrovirus infection and co-infection, and intravenous substance use, on immune function in African-Americans. DESIGN: A cohort of South Florida street-recruited African-American intravenous drug users formed the study population. The cohort consisted of 90 HIV-negative & human T-lymphotropic virus (HTLV)-negative, one HIV-negative & HTLV-I-positive, 11 HIV-negative & HTLV-II-positive, 79 HIV-positive & HTLV-negative, one HIV-positive & HTLV-I-positive and 21 HIV-positive & HTLV-II-positive individuals. The results reported are for the cross-sectional, baseline assessment of immune parameters. METHODS: Lymphocyte phenotypic distributions and functional markers, including proliferative response to mitogens and natural killer cell cytotoxicity, were determined. Serum immunoglobulin (Ig) levels were determined as a measure of B-cell activity. RESULTS: HTLV-II infection was associated with increases in CD8 lymphocyte count and serum Ig, but with no other significant immunologic changes. The distribution of CD4 and CD8 percentages, CD4:CD8 ratio, phytohemagglutinin (PHA) and pokeweed mitogen (PWM) reactivity, IgA and IgG for the four retrovirus serostatus groups suggested the possibility of interactive effects in the co-infected group, as demonstrated by a trend toward lower medians for CD4 and for PHA and PWM response and higher medians for IgG, IgA and CD8. Retrovirus-seronegative intravenous drug users had significantly impaired immune status compared with non-drug-using control individuals. CONCLUSIONS: Immunologic dysfunction attributable to HTLV-II infection was minor compared with HIV infection in this population. Study subjects who were co-infected with HIV and HTLV demonstrated more impairment of immune function than individuals with single retrovirus infections.

Adult↗
PubMed1976

Lymphocyte transformation in human plasma without addition of synthetic medium. A study of immune function in patients with chronic uraemia or diabetes mellitus.

The in vitro response of lymphocytes obtained from normal subjects, uraemic patients on haemodialysis and diabetic patients was studied using cultures containing either medium plus plasma (medium cultures) or plasma alone (plasma cultures). The study demonstrated that plasma alone can adequately support lymphocyte transformation induced by nonspecific mitogens (PHA and PWM) and allogeneic lymphocytes in mixed lymphocyte culture (MLC) reaction. This investigation further confirms our previously reported findings that uraemic patients undergoing haemodialysis have a normal lymphocyte response in MLC and to PHA and PWM. Plasma cultures give results similar to conventional medium cultures in subjects where lymphocyte transformation is normal. The lymphocyte hyporactivity observed in diabetics is, however, better shown in the plasma cultures. The suppressed response of the diabetic patient's lymphocytes to PHA and PWM both in the presence of autologous and normal AB plasma suggests intrinsic lymphocyte dysfunction as the explanation for impaired immune function. Plasma cultures may provide a better in vitro system for the evaluation of immune function in certain groups of patients where it is desirable to distinguish between intrinsic abnormalities of lymphocyte function and the effect of humoral immunosuppressive factors.

Adult↗
PubMed1998

Small volumes of enteral feedings normalise immune function in infants receiving parenteral nutrition.

BACKGROUND/PURPOSE: Parenteral nutrition (PN) is associated with a risk of septicaemia. This may be caused by impairment of immune function related to PN. The authors investigated the effects of the addition of enteral feedings to PN on the immune status of human newborn infants. METHODS: Ten surgical infants (age less than 6 months) requiring PN were studied in two consecutive phases: (A) after 31.1+/-6.0 days (mean +/- SEM) of PN with no enteral feeding (total PN); and (B) after 4.7+/-1.1 days from the addition of small volumes of enteral feeding to PN. Full blood count and liver function tests were not significantly different between phases A and B. A control group (n = 9) of infants receiving a normal enteral diet was also studied. Host bactericidal activity against coagulase-negative staphylococci (CNS) was measured by an in vitro whole blood model. Bacterial killing was measured after a 45-minute bacterial challenge using the Miles-Misra technique. Tumour necrosis factor-alpha (TNF-alpha) was measured by enzyme-linked immunosorbent assay (ELISA) after 2 hours of bacterial challenge. RESULTS: The lowest level of CNS killing (37.7+/-5.2%), was observed in patients receiving total PN. This increased significantly after the addition of small enteral feeds (52.0+/-4.6%, P < .005) approaching the levels measured in controls (65.1+/-3.4%). TNF-alpha production was low during total PN (1467+/-297 pg/mL) and rose significantly after the addition of minimal enteral feeds (4,661+/-1,311 pg/mL, P < .05). The increase in CNS killing after the addition of small enteral feeds in patients on PN was significantly correlated with the duration of enteral feeding (r = 0.8, P = .006). CONCLUSIONS: These results indicate that the introduction of small volumes of enteral feed improve the impaired killing of CNS and the abnormal cytokine response observed during total PN. This implies that stimulation of the gastrointestinal tract may modulate immune function in neonates and prevent bacterial infection.

Bacteremia↗
PubMed1994

[Effects of crowding on immune functions in mice].

The effects of several types of crowding on immune functions were studied in mice. This study consisted of two experiments. Experiment one: Male BALB/c mice were initially housed in groups of four mice per cage. After fourteen days of acclimation, the mice were randomly divided into three groups, Control (four mice per cage, control group), Crowd-I (four mice per small space) and Crowd-II (sixteen mice per cage). These conditions were maintained for seven days. The results of experiment one were as follows: (1) The percentage of lymphocytes in the blood of Crowd-II was significantly lower than that of Control (p < 0.05). (2) The percentage of neutrophils and the absolute number of neutrophils in blood of Crowd-II were significantly higher than in Control (p < 0.05). (3) Superoxide production activity (NBT reduction activity) of blood neutrophils in Crowd-II tended to be depressed, and phagocytic activity of neutrophils was significantly depressed in Crowd-II as compared with Control (p < 0.01). These results suggest that the complexity of interrelationships among mice caused by an increase in the number of animals per cage is a very important stress factor. Experiment two: Male BALB/c mice were initially housed in groups of five mice per cage. After fourteen days of acclimation, the mice were divided into three groups, Control (five mice per cage, control group), Crowd-(1) (five mice per cmall space) and Crowd-(2) (twenty mice per cage). In Control and Crowd-(1), the same mice were used as in the acclimation period. These conditions were maintained for seven days. In this period, on the second day, all the mice were injected intraperitoneally with sheep red blood cells (SRBC). The results of experiment two were as follows: (1) The specific humoral immune response to SRBC was investigated in terms of the number of PFC in the spleens and hemagglutination in sera, but significant differences were not found among the groups. (2) Plasma IgG levels in the Crowd-(1) were significantly higher than those in Control (p < 0.05). (3) Both superoxide production activity and phagocytic activity of neutrophils were significantly depressed in Crowd-(2) as compared with Control (p < 0.01, respectively), whereas each neutrophil function of Crowd-(1) tended to be enhanced as compared with Control.

Animals↗
PubMed1977

Immune function in ankylosing spondylitis: apparent relationship between streptococcal responses and HLA B27.

Immune function has been evaluated in 54 patients with ankylosing spondylitis (AS) and 26 controls. Cell-mediated immunity was assessed by skin testing with ubiquitous antigens, and humoral immunity by antibody responses to tetanus toxoid and Salmonella typhi vaccinations, and resting titres of anti-Streptolysin O, anti-E Coli, and isohemagglutinins. The AS patients had reduced delayed hypersensitivity responses to Candida, augmented responses to Streptococcal antigen and relatively low ASO titres. There was no generalized depression of humoral immunity, as indicated by the normal tetanus and Salmonella O responses and hyper-response to Salmonella H antigen. The E. Coli and isohemagglutinin titres were normal. These results indicate that patients with AS present a complex immunological profile, including exaggerated responses to some antigens and impaired responses to others. In view of the very high incidence of HLA-B27 in AS, it is possible that these findings are related to the effects of HLA associated immune response genes.

Adult↗
PubMed2001

Postgrafting administration of granulocyte colony-stimulating factor impairs functional immune recovery in recipients of human leukocyte antigen haplotype-mismatched hematopoietic transplants.

In human leukocyte antigen haplotype-mismatched transplantation, extensive T-cell depletion prevents graft-versus-host disease (GVHD) but delays immune recovery. Granulocyte colony-stimulating factor (G-CSF) is given to donors to mobilize stem cells and to recipients to ensure engraftment. Studies have shown that G-CSF promotes T-helper (Th)-2 immune deviation which, unlike Th1 responses, does not protect against intracellular pathogens and fungi. The effect of administration of G-CSF to recipients of mismatched hematopoietic transplants with respect to transplantation outcome and functional immune recovery was investigated. In 43 patients with acute leukemia who received G-CSF after transplantation, the engraftment rate was 95%. However, the patients had a long-lasting type 2 immune reactivity, ie, Th2-inducing dendritic cells not producing interleukin 12 (IL-12) and high frequencies of IL-4- and IL-10-producing CD4(+) cells not expressing the IL-12 receptor beta(2) chain. Similar immune reactivity patterns were observed on exposure of donor cells to G-CSF. Elimination of postgrafting administration of G-CSF in a subsequent series of 36 patients with acute leukemia, while not adversely affecting engraftment rate (93%), resulted in the anticipated appearance of IL-12-producing dendritic cells (1-3 months after transplantation versus > 12 months in transplant recipients given G-CSF), of CD4(+) cells of a mixed Th0/Th1 phenotype, and of antifungal T-cell reactivity in vitro. Moreover, CD4(+) cell counts increased in significantly less time. Finally, elimination of G-CSF-mediated immune suppression did not significantly increase the incidence of GVHD (< 15%). Thus, this study found that administration of G-CSF to recipients of T-cell-depleted hematopoietic transplants was associated with abnormal antigen-presenting cell functions and T-cell reactivity. Elimination of postgrafting administration of G-CSF prevented immune dysregulation and accelerated functional immune recovery.

Acute Disease↗
PubMed1998

[The effect of a vaccine made from 39kd hydrophobic outer membrane protein of Leptospira interrogans on neurohumoral and red cell immunity function of the guinea pigs].

A randomized control trial was conducted to determine the immunoprotective efficacy of OmpL39. 36 guinea pigs were divided into OmpL39 group, whole leptospiral cell vaccine (WLCV) group, other proteins of Leptospira group, and negative control group (normal saline, NS). The results showed that all the guinea pigs of infected OmpL39 and WLCV still survived, but all the control guinea pigs died. Immunoprotective efficacy was 100% for OmpL39 and WLCV. OmpL39 levels were similar to WLCV levels and higher than controls (P < 0.05). These suggested that OmpL39 could be used as important immunoprotective antigen to develop the genetic vaccine of the targeting delivery system. Also it was observed that OmpL39 could produce 100% immunoprotective efficacy, have higher MAT level (> 1:3200) and regulate 5-HT, 5-HIAA, DA, NE. The 5-HT, DA, NE concentration was lower and 5-HIAA was higher than that of controls after stimulating the guinea pigs with OmpL39 (P < 0.05). The results suggested that OmpL39 genetic vaccine could produce immunity function and have an active effect on absorbing inflammation and protecting organs and tissues. Besides, the red cell immunity efficacy of the guinea pigs was changed during immunity response and the RBC-C3b RR and the RBC-ICR were increased. The RFER was increased; the RFIR was decreased. RFER/RFIR was remarkably higher than that of control (P < 0.05). These suggested that OmpL39 could increase red cell immunity function.

Animals↗
PubMed1999

Enhancing versus suppressive effects of stress hormones on skin immune function.

Delayed-type hypersensitivity (DTH) reactions are antigen-specific cell-mediated immune responses that, depending on the antigen, mediate beneficial (e.g., resistance to viruses, bacteria, and fungi) or harmful (e.g., allergic dermatitis and autoimmunity) aspects of immune function. Contrary to the idea that stress suppresses immunity, we have reported that short-duration stressors significantly enhance skin DTH and that a stress-induced trafficking of leukocytes to the skin may mediate this immunoenhancement. Here, we identify the hormonal mediators of a stress-induced enhancement of skin immunity. Adrenalectomy, which eliminates the glucocorticoid and epinephrine stress response, eliminated the stress-induced enhancement of skin DTH. Low-dose corticosterone or epinephrine administration significantly enhanced skin DTH and produced a significant increase in the number of T cells in lymph nodes draining the site of the DTH reaction. In contrast, high-dose corticosterone, chronic corticosterone, or low-dose dexamethasone administration significantly suppressed skin DTH. These results suggest a role for adrenal stress hormones as endogenous immunoenhancing agents. These results also show that hormones released during an acute stress response may help prepare the immune system for potential challenges (e.g., wounding or infection) for which stress perception by the brain may serve as an early warning signal.

Adrenalectomy↗