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PubMed2001

The impact of highly active antiretroviral therapy on HIV-specific immune function.

Highly active antiretroviral therapy (HAART) can suppress HIV type 1 plasma viremia to undetectable levels for up to 3 years or more. When the therapy is discontinued, viral rebound occurs in a majority of patients, indicating that HAART is unable to completely eradicate the virus. Initial calculations of the half-lives of the infected cells (estimated to be 14-21 days) suggested that only 3 years continuous HAART therapy would be necessary to achieve complete eradication; however, several studies have determined that the half-lives of chronically infected cells are in the order of 6-44 months. New estimates indicate that it may take as long as 60 years to eradicate the virus. Thus, there has been movement toward combining HAART with various means of augmenting and/or reconstituting the host's immune system, especially HIV-1-specific immune responses. The long-term goal is to discontinue HAART and permit the reconstituted immune system to contain whatever small amounts of the virus remain.

Acquired Immunodeficiency Syndrome↗
PubMed1979

Impaired immune function and identification of polybrominated biphenyls (PBB) in blood compartments of exposed Michigan dairy farmers and chemical workers.

In 1973 PBB's were accidentally mixed into animal feed, resulting in marked toxic effects. Meat and dairy products were widely consumed in Michigan. To determine the impact of PBB's, 55 exposed Michigan farm residents, 11 Michigan chemical workers and 46 non-exposed Wisconsin farmers were examined. Abnormalities included decreased number of T-lymphocytes with concomitant increase of lymphocytes with no detectable surface markers, "null cells", and altered lymphocyte function. Data obtained from skin testing using standard recall antigens, showed no consistent correlation between the delayed cutaneous hypersensitivity response and the impaired lymphocyte function. PBB (hexa) in separated white blood cells and red cells was positively identified and quantified by gas chromatography-mass spectrometry. PBB and immunological abnormalities were not detected in non-exposed Wisconsin dairy farm residents.

Agricultural Workers' Diseases↗
PubMed2004

Odor from industrial hog farming operations and mucosal immune function in neighbors.

The authors evaluated whether exposure to malodor from industrial hog farming operations has a psychophysiologically mediated immunosuppressive effect on secretory immunoglobulin A (sIgA) in neighbors. Fifteen adults living within 2.4 km (1.5 mi) of at least one hog farming operation rated odor intensity on a 9-point scale and provided saliva samples twice daily for two weeks. The authors used hierarchical regression to model the association between reported odor and sIgA; study participants were their own controls. The natural log of slgA concentration and secretion rate declined, on average, 0.058 (0.032) and 0.116 (0.103), respectively, for each incremental 1-unit increase in reported odor from 4 to 9, adjusted for time of day, suggesting reduced levels of sIgA in response to moderate or high odor. Findings support the hypothesized immunosuppressive effect of malodor on mucosal immunity and provide preliminary data useful in understanding health effects related to malodor from industrial hog farming operations.

Adult↗
PubMed1989

Relationship between acupuncture-induced immunity and the regulation of central neurotransmitters in the rabbit: VI. The influence of NDR stimulation on acupuncture regulation of immune function in rabbit.

T-lymphocyte transformation ability decreased and the function of the B-lymphocyte and mononuclear leucocyte/macrophage system increased when the activity of central serotonergic neurons was enhanced by the stimulation of nucleus dorsal raphe (NDR). These changes induced by NDR stimulation were not effected by electroacupuncture (EA) when EA was performed on the background of NDR stimulation. By comparing these results with the previous resultant that immunoreactions were affected by locus coeruleus (LC) stimulation and LC stimulation plus EA, some regularity had been discovered. So, a hypothesis was put forward by us that the catecholaminergic system plays a main role in EA regulation of cellular immunity while the serotonergic system plays such a role in EA regulation of humoral immunity.

Animals↗
PubMed1976

Influence of protein restriction on immune functions in NZB mice.

The influence of a low protein (6%) diet on the immunologic function of NZB mice was investigated. The low protein intake was associated with decreased weight gain in both male and female NZB mice. The mice fed the low protein diet did not develop splenomegaly, which generally occurs by 7 to 10 months of age in NZB mice fed a normal amount of protein. Further, 7- to 10-month-old NZB mice fed the low protein(6%) diet, maintained: 1) more vigorous antibody production to sheep red blood cells; 2) greater capacity to produce graft-vs-host reactions, and 3) more vigorous cell-mediated "killer" cell immunity after immunization against DBA/2 mastocytoma cells than did NZB mice on a normal (22%) protein diet. The decrease of PHA and Con A response which normally occurs with aging in NZB mice was abrogated to some degree by protein restriction. However, response to LPS, which also declines with age in NZB mice, did not appear to be influenced by diet.

Animals↗
PubMed1983

Immune function in aging atomic bomb survivors residing in the United States.

Immunologic parameters were studied among survivors of the 1945 atomic bombs who now reside in the United States. Of all known survivors living in the U.S., about 40% (n = 189) participated in this study. Of those survivors on whom radiation exposure information was available (n = 168), 96% were exposed to less than 50 rad at the time of the bomb (ATB). Survivors were divided into two groups; those exposed to varying low doses of radiation (S+ group, exposed at less than or equal to 2500 m from the hypocenter) were compared with those exposed to "O rad" (S0 group, exposed at greater than 2500 m from the hypocenter). Of the former group, 92% were exposed to less than 100 rad and 89% to less than 50 rad ATB. Cellular immune responses, including natural cell-mediated cytotoxicity (NCMC), interferon production, and the mitogenic response to PHA, tended to be higher among S+ individuals, although only the difference for NCMC was statistically significant. This was suggestive of a trend which was consistent with the higher serum interferon levels and lower frequencies of detectable immune complexes and antimitochondrial antibodies among the S+ group, although these differences were not statistically significant. Other immunologic parameters which showed no trend included frequency of antinuclear antibodies, rheumatoid factor, levels of serum immunoglobulins, levels of isoantibodies and heteroantibodies, and the magnitude of the mixed lymphocyte reaction.

Adolescent↗
PubMed1996

In vitro restoration of T cell immune function in human immunodeficiency virus-positive persons: effects of interleukin (IL)-12 and anti-IL-10.

Cells from human immunodeficiency virus (HIV)-positive patients were evaluated for their in vitro responsiveness to recall antigen, alloantigen, and phytohemagglutinin (PHA) following the in vitro addition of interleukin (IL)-12 or anti-IL-10. Three-color flow cytometric analysis of CD4 and CD8 subsets was done to determine whether specific in vivo alterations in cell surface markers are associated with in vitro function changes. The results demonstrated a hierarchical response pattern to recall antigens versus alloantigen versus PHA, and these in vitro responses were associated with the number and activation status of CD4 cells. The in vitro addition of IL-12 or anti-IL-10 could restore antigen responses (HIV envelope peptides or influenza) in patients with 200-500 CD4 cells/microL; however, in patients with < 200 CD4 cells/microL, this improved response was limited to the influenza response. Studies of this nature may provide important insights into the role of cytokines in the natural history of HIV disease, and they suggest that immune therapy of this type may be most effective in patients who have more preserved immune systems.

Antibodies↗
PubMed1987

[The outcome of viral hepatitis B and cellular immunity function].

Immunological examination of 158 patients with viral type B hepatitis (VH) was performed over time. Patients with HBsAg elimination for 60 days from the onset of jaundice and a favorable outcome of hepatitis at the height of the process demonstrated a decrease in the relative number of theophylline resistant lymphocytes (T-helpers), a decrease in theophylline sensitive lymphocytes (T-suppressors), an increase in the helper/suppressor (H/S) ratio up to 13.1/1 (the normal ratio being 3.9/1), a certain increase in the number of B-lymphocytes, activation of rosette-forming function of neutrophils, and a tendency to an increase in the activity of natural killer cells (NK). Patients with HBs-antigenemia over 60 days with subsequent convalescence also demonstrated similar changes of immunoregulating T-lymphocyte subpopulations but they developed later in relation to the onset of viral hepatitis. In the formation of chronic persistent hepatitis (CPH) there was no decrease in the absolute and relative number of T-suppressors from the onset of disease, the level of T-helpers and the H/S ratio were moderately lowered. Unlike CPH the suppression of the effector link of the immune system (phagocytosis and NK) and a decrease in the level of T-suppressors were noted in the development of chronic active hepatitis in all the periods of the process. The application of the above regularities to prognosis of VH outcomes, the choice and assessment of efficacy of immunocorrective therapy was discussed.

Adolescent↗
PubMed1982

Immune function in pure iron deficiency.

Immunologic studies were performed in ten iron-deficient children, aged 12 to 30 months, before and after iron replacement. Chronic infection, malnutrition, and vitamin deficiency were excluded. Mean hemoglobin levels went from 8.2 +/- 0.2 (SEM) to 12.3 +/- 0.3 g/dL after iron replacement. Mean T-cell percentage increased from 50% +/- 3.0% to 58% +/- 3.7%. Absolute numbers of T cells were unchanged. Three children converted negative in vitro proliferative responses to Candida or tetanus antigen. Mean stimulation indexes increased for Candida (6.8 +/- 1.7 to 17.9 +/- 6.7) and tetanus (19.5 +/- 6.0 to 31.7 +/- 8.5). Nine of 16 delayed hypersensitivity skin tests were positive before and ten of ten were positive after iron therapy. The IgG and IgA levels did not change significantly, but IgM levels decreased from 181 +/- 13 to 128 +/- 5 mg/dL. We conclude that T-cell immunity is slightly impaired in pure iron deficiency and that these subtle defects can be corrected with oral iron replacement.

Anemia, Hypochromic↗
PubMed1987

Surface glycoproteins of influenza virus increase cell-mediated immunity functions in mice.

T-lymphocyte blastogenic response to Concanavalin A, interleukin-2 (IL-2) production and NK cell activity were studied in three groups of Balb/c mice infected with intranasal inoculum of A/Chile/1/83 (H1N1) influenza virus, vaccinated with same virus glycoproteins and infected fifteen day after vaccination. Virus infection results in T-cell function impairment. In fact T-cell blastogenic response and IL-2 production are profoundly decreased as early as 24 hours, whereas NK cell activity is depressed only later. Instead viral glycoprotein vaccination induces an enhancement of CMI related parameters and protects the host from virus immunosuppressive effects.

Animals↗
PubMedDate not supplied

Modulation by enteral nutrition of the acute phase response and immune functions.

To use nutrition in order to limit the negative consequences of physical and mental stress is not new. Recent advances in immunology and particularly in the understanding of the chemical language used to communicate both by eukarytic and prokarotic cells has made it easier to objectively evaluate effects of various immunomodulating efforts including the use of nutrients, vitamins and antioxidants in preventing or limiting the development of disease and its late consequences.

Acute-Phase Reaction↗
PubMed1982

Recovery of immune function after cessation of maintenance therapy in acute lymphoblastic leukemia (ALL) of childhood.

In previously healthy children, serum immunoglobulin levels at diagnosis of acute lymphoblastic leukemia (ALL) were entirely in the normal range. After antileukemic therapy had been given for 26-27 months, serum immunoglobulin levels were low. In 32 children these parameters could be followed for periods up to 3 years after cessation of therapy, the patients remaining in unmaintained remission. At cessation of therapy serum immunoglobulin levels were at the tenth centile of the normal range or slightly below. IgG promptly returned to normal levels and then remained in the normal range. IgA levels were restored much more slowly. Most striking was the slow and incomplete return of serum IgM to normal levels. Even after a follow-up of 3 years the mean was still subnormal. This was not accompanied by clinical signs of disturbed immunity. Our study points out that in assessing the long-term immunosuppressive effects of anticancer therapy the follow-up period must be sufficiently long.

Adolescent↗
PubMed1989

Qualitative analyses of cellular immune functions in equine infectious anemia show homology with AIDS.

Equine infectious anemia (EIA) is a disease caused by a lymphocytotropic lentivirus which belongs to the same subfamily as HIV. Because of the very close relationship of their predicted gag and pol gene products and similarities in clinical manifestations of the disease, EIA served as a model to study immunological events involved in the host defence against lymphocytotropic viral infections. The existence of antibody dependent cell-mediated cytotoxicity against autologous EIA virus infected lymphoblasts was demonstrated in vitro at the beginning of an acute attack of the disease. Cytotoxic activity was not found or was very low during chronic infection. Reactivity of peripheral blood lymphocytes to Protein A and allogeneic cells in vitro was significantly suppressed in the presence of an acute serum, while the reactivity to PHA was at the normal level. These results suggest that cellular immune mechanism(s) are also involved in removal of EIA virus infected cells as has been reported recently in HIV-1 infected individuals and that EIAV and HIV immunopathogenesis show similarities in affecting the immune response of the host.

Acquired Immunodeficiency Syndrome↗
PubMed1995

[Effect of deoxynupharidine on immune function in vitro].

Deoxynupharidine (DON) is an alkaloid isolated from rhizome Nuphar pumilum which has been extensively used in the treatment of rheumatoid arthritis and back and leg pains as a folk remedy in China. Data presented in this paper indicate that the DON has potent immunosuppressive activities. Mitogens or allogen induced lymphoproliferative responses of murine splenocytes or human tonsillar mononuclear cells (hTMNC) were markedly reduced when DON was added in the cultures. The trypan blue exclusion test showed that this inhibition was not exerted through a toxic effect. IL-2 activity in the supernatants was evaluated for its ability to support IL-2 independant cell line (CTLL-2) proliferation and the results showed that DON had no marked effect on IL-2 level, but inhibited the capacity of murine peritoneal macrophages to produce IL-1 and TNF, which play very important roles in the process of inflammation and immune response. This immunosuppressive actions of DON may partly account for some of its potential in the treatment of chronic inflammatory diseases, where immunological mechanisms are known to play a major pathogenic role.

Animals↗
PubMed1990

Experimental approach to the study of immune function in children with possible human immunodeficiency virus infection.

The clinical immunology laboratory is often called on to assess risk in pediatric patients with clinical evidence of immunodeficiency and possible human immunodeficiency virus (HIV) exposure while antibody tests are being considered or are underway. Since non-HIV-related conditions including neoplasia, certain viruses, and primary immunodeficiency can potentially produce lymphocyte subset imbalance and functional impairment, there is need for a laboratory approach to differential analysis of pediatric immunodeficiency. In addition, laboratory methods may also influence the results obtained. In order to investigate these issues, we screened pediatric patients with and without HIV exposure. Altered lymphocyte subset expression and function were found among non-HIV-infected pediatric patients. The use of percentage and absolute lymphocyte numbers was found to affect the results obtained in a significant manner. Some patients who were chronic blood transfusion recipients were found to have blocking factors, presumably alloantibodies, in serum, which affected detection of lymphocyte surface antigens. In this population, age at seroconversion was a factor influencing subsequent levels of CD4+ T lymphocytes. Significant differences in CD4+ T lymphocyte percentages were also observed in children congenitally exposed to HIV compared with controls, even among those children with CD4/CD8 ratios greater than 1.0, who therefore had possibly escaped infection. Immune changes in children should be interpreted with caution.

Adolescent↗
PubMed1990

Feline immunodeficiency virus (FIV) infection in the cat as a model for HIV infection in man: FIV-induced impairment of immune function.

To assess the value of feline immunodeficiency virus (FIV) infection as a model for human immunodeficiency virus (HIV) infection in man, we studied the impairment of certain immunological functions following natural or experimental FIV infection. Proliferative responses of peripheral blood mononuclear cells (PBMC) from symptomatic and asymptomatic cats after naturally or experimentally acquired FIV infection, induced by activation with the mitogens concanavalin A, pokeweed mitogen, or lipopolysaccharide or by stimulation with human interleukin-2 (IL-2), were significantly lower than the proliferative responses found with PBMC from noninfected control cats. Also IL-2 production levels of mitogen-activated PBMC from naturally infected symptomatic cats were significantly reduced. These data confirm that the pathogenesis of FIV infection in the cat, like HIV infection in man, is characterized by a serious malfunction of the immune system.

Animals↗
PubMed1980

Life-long dietary protein restriction and immune function: responses to mitogens and sheep erythrocytes in BALB/c mice.

Effects of chronic dietary protein restriction on immunological response were studied in BALB/c male mice. Three diets were used: 4, 8, 24% protein (casein) which 1000 mice were allowed to eat ad libitum. Restricted mice were not malnourished. Mice subjected to 4% protein diet had life expectancy that was marginally significantly prolonged when compared with "control" mice eating 24% protein diet. In vivo primary antibody responses to sheep erythrocytes, assessed by plaque formation and serum hemagglutination, were lower in 4% protein fed mice than in those eating 24% protein diets. Primary antibody responses fell with age in all diet groups. In vitro splenic lymphocytic blastogenesis, measured by 3H-thymidine uptake to concanavalin A, phytohemagglutinin, lipopolysaccharide, and allogenic lymphocytes, was not significantly influenced by diet. Thymus weight was not importantly influenced by diet. Spleens from mice eating 4% protein diet and immunized with sheep erythrocytes were significantly smaller than those from control animals. Our findings are consistent with several other reports, and indicate that this type of diet restriction does not delay onset of aging patterns found in the immune system.

Aging↗
PubMed1983

Alteration of immune function by staphylococcal pyrogenic exotoxin type C: possible role in toxic-shock syndrome.

Staphylococcal pyrogenic exotoxin type C (PE-C) suppressed synthesis of IgM antibodies to sheep erythrocytes by in vitro cultures of murine and rabbit splenocytes. Maximal suppression was observed on day 4 of culture and at PE-C doses of 0.1 and 0.01 microgram per 10(7) splenocytes. Endotoxin, added to cell cultures containing PE-C, caused further suppression of IgM synthesis. Endotoxin alone added to cultures was not immunosuppressive. Sublethal doses of PE-C plus endotoxin also suppressed complement-fixing antibody responses in rabbits to sheep erythrocytes; neither agent alone was suppressive. Further, the combination of PE-C and endotoxin blocked reticuloendothelial clearance of colloidal carbon by 50% during a 20-min period. PE-C enhanced the skin reactivity of rabbits previously sensitized to purified protein derivative. One-half of rabbits immunized with PE-C emulsified in adjuvant failed to make antibody to PE-C during a 112-day period. The animals that were nonresponsive to PE-C were able to make antibodies to sheep erythrocytes.

Animals↗

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