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PubMed1987

Protein deficiency reduces natural antitumor immunity.

Clinical data have shown that neoplastic diseases and/or related therapies frequently result in protein depletion of tumor-bearing patients. Depressions of acquired and specific immunity caused by protein depletion are well known. In an experimental model protein depletion was induced by lack of nutritional protein in otherwise isocaloric conditions in BALB/c and C57BL/6 mice over various time periods (max. 35 days). The results show that natural immune effector cells, natural killer cells, and monocyte/macrophages also during treatment with biological response modifiers (BRM) are depressed in their cytotoxic potentials in vitro and in vivo. Substantial and critical reductions of bone marrow cellularity (bone marrow nucleated cells) were also observed. In contrast, preliminary results show that if, following protein depletion, mice were treated parenterally with amino acids (Neo-aminomel, Boehringer-Ma. Co., FRG) complete restoration of immune parameters takes place. Adequate protein status is shown to be a crucial factor for natural immunity and therapy with BRM.

Animals↗
PubMed1985

Naturally acquired immunity to tetanus toxin in an isolated community.

Literature on natural immunity to tetanus is scarce. We examined antitetanus antibody levels with the enzyme-linked immunosorbent assay in 200 people living in an isolated community and clarified the influence of age and sex on immunity. In 197 subjects, antitoxin antibodies were measured. No sex differences were noted, and 30% had protective levels (above 0.01 IU/ml). The percentage of those considered protected was age dependent.

Adolescent↗
PubMed2006

Immune responses to asexual blood-stages of malaria parasites.

The blood stage of the malaria parasite's life cycle is responsible for all the clinical symptoms of malaria. The development of clinical disease is dependent on the interplay of the infecting parasite with the immune status and genetic background of the host. Following repeated exposure to malaria parasites, individuals residing in endemic areas develop immunity. Naturally acquired immunity provides protection against clinical disease, especially severe malaria and death from malaria, although sterilizing immunity is never achieved. Given the absence of antigen processing in erythrocytes, immunity to blood stage malaria parasites is primarily conferred by humoral immune responses. Cellular and innate immune responses play a role in controlling parasite growth but may also contribute to malaria pathology. Here, we analyze the natural humoral immune responses acquired by individuals residing in P. falciparum endemic areas and review their role in providing protection against malaria. In addition, we review the dual potential of cellular and innate immune responses to control parasite multiplication and promote pathology.

Animals↗
PubMed1998

[Natural antileptospirosis immunity in donor-capable subjects].

Natural antileptospirosis immunity of blood giving capable population of Kyïv was studied in 853 persons. It has been ascertained that during a year natural antileptospirosis antibodies can be found out in blood serum of people with different by ABO system blood groups. Antileptospirosis antibodies of high titres (> 1:80) are mostly present in spring and autumn.

ABO Blood-Group System↗
PubMed1983

Taenia solium: cell reactions to the larva (Cysticercus cellulosae) in naturally parasitized, immunized hogs.

In hogs naturally infected with Taenia solium larvae (i.e., Cysticercus cellulosae), we studied the host response induced by antigens obtained from the larvae. Histopathological studies of cysticerci removed after 4 and 8 weeks of immunization showed an intense inflammatory reaction surrounding the larvae. The response was greater in the 8-week specimens. A dense layer of eosinophils was in close contact with the external membrane of the bladder wall and, in several cases, the eosinophils had infiltrated this tegument. Many eosinophils were seen in the spiral canal of larvae. This infiltration by eosinophils increased with time. Preparations from the 8-week samples showed many degenerated and disrupted eosinophils whose granules were found in close contact with the outer membrane of the larval tegument and, in some cases, had entered through the broken surface of this structure. More than 90% of the larvae were found in various stages of degeneration; the rest were completely destroyed and surrounded by a mass of eosinophils. After immunization, peripheral blood eosinophilia increased to 17%, whereas the eosinophilia of the control hog was 4% throughout the study. The larval worms removed from control hogs showed intact structures, with a low degree of infiltration by eosinophils and a discrete inflammatory reaction surrounding the bladder wall of the larvae.

Animals↗
PubMed1967

Natural and immune human antibodies reactive with antigens of virulent Neisseria gonorrhoeae: immunoglobulins G, M, And A.

Natural and immune human antibodies reactive with heat-labile and heat-stable antigens of virulent Neisseria gonorrhoeae were studied by use of an indirect fluorescent-antibody (IFA) procedure. The immunoglobulin class of the reactive antibodies was identified by using fluorescein-conjugated antisera specific for human IgG, IgA, or IgM in the IFA procedure. The effects of heat and mercaptoethanol on IFA reactivities were also studied. It appeared that antibodies of the IgG, IgM, and IgA classes present in the sera of both infected persons (immune antibodies) and normal persons with no history of gonococcal infection (natural antibodies) react with heat-stable somatic antigens. Immune IgG antibodies, however, were distinguishable from natural IgG antibodies by their ability to recognize heat-labile surface antigens. The distinction between natural and immune IgM antibodies was less obvious. IgM antibodies from both infected and normal persons appeared to react with heat-labile antigens. Some, but not all, infected persons had immune IgA antibodies to heat-labile as well as to heat-stable antigens. Treatment of sera with mercaptoethanol had no effect on IgG antibodies. The IFA activity of IgM antibodies was decreased, but not abolished. The effects of mercaptoethanol on IgA antibodies were variable. Some sera showed a decrease in IgA titer, and others showed an increase in IgA activity to certain antigens. Immune IgG antibodies were more resistant to heating than were natural IgG antibodies. Natural and immune IgM antibodies appeared equally sensitive to heating. IgA activity, on the other hand, was increased by heating sera at 60 C, but was decreased at higher temperatures. Thus, it appears that natural and immune human IgG antibodies to N. gonorrhoeae may be distinguished by their interactions with heat-labile antigens and by their resistance to heating.

Antigen-Antibody Reactions↗
PubMed1989

[The immune structure of the population of the Bashkir ASSR in connection with hemorrhagic fever with renal syndrome and the relation of indices of collective immunity to morbidity and the nature of the landscape].

The study of 9,176 serum samples obtained from all regions and 15 cities of Bashkiria, carried out by the method of radioimmunoassay with the use of the antigen of hemorrhagic fever with the renal syndrome (HFRS), has revealed considerable differences in the size of the natural immune stratum of the population (43.9-0.8%). The size of such immune stratum characterizes the activity of natural foci: the largest immune stratum (25.4%) exists among the population of regions with broad-leaved forests, this stratum is somewhat less (12.2-13.2%) in regions with combined coniferous and broad-leaved forest, in regions with different combinations of broad-leaved forests and steppes, as well as mountain forests. On the Aĭsko-Kungurskaia forest-steppe territory and in regions characterized by a combination of steppe areas with mountain forests the immune stratum has been found to be even lesser (7.3-8.4%). The least immune stratum (3.4%) exists in steppe regions. By comparing the percentage of the population immune to HFRS and having had the diagnosis of HFRS over the period of 30 years the quality of the clinical diagnosis of this infection on the given territory may be determined.

Antibodies, Viral↗
PubMed2005

Natural killer cell immune responses.

Natural killer (NK) cells play a vital role in innate immune responses to infection; they express activation receptors that recognize virus-infected cells. Highly related to receptors recognizing tumor cells, the activation receptors trigger cytotoxicity and cytokine production. NK cells also express inhibitory receptors for major histocompatibility complex (MHC) class I molecules that block the action of the activation receptors. Although many ligands for NK cell receptors have MHC class I folds, recent studies also indicate ligands resembling the NK cell receptors themselves. A combination of immunologic, genetic, biophysical, and in vivo approaches is being employed to understand fully how these receptors contribute to NK cell activities in innate immunity to pathogens and tumors.

Animals↗
PubMed1999

Lessons learned about the therapeutic potential of the natural human immune response to lung cancer.

Lung cancer is the leading cause of cancer deaths; patients with this disease often develop antibodies to their own tumour antigens. TB94 is one such human antibody, and was obtained from the natural immune response from a patient with lung cancer. The data generated so far on TB94 suggest that this human antibody may have clinical applications in the diagnosis and treatment of lung cancer. Since humans make antibodies to tumour antigens, the intelligence of the human immune response can be exploited for the discovery of potential novel antigens. These novel antigens can then be developed for vaccine applications. Creating effective strategies to analyse systematically the natural human immune response to tumour antigens will open up new areas of immunotherapy for the control and eradication of disease.

Journal Article↗
PubMed1997

The immune-suppressive nature of pain.

OBJECTIVES: To review evidence that the immune system plays a role in controlling the spread of cancer and findings that perioperative pain relief improves immune status and health outcomes. DATA SOURCES: Research studies and review articles pertaining to immunity, immune function, stress, and immune-suppressive nature of pain. CONCLUSIONS: Pain not only results in suffering but is a pathogen itself, capable of facilitating the progression of metastatic disease. Adequate pain relief decreases these risks. IMPLICATIONS FOR NURSING PRACTICE: Adequate pain relief is not only a primary concern in caring for individuals in pain but may be a matter of physiologic necessity as further studies reveal the immune-suppressive nature of pain.

Analgesics, Opioid↗
PubMedDate not supplied

Innate immunity.

For more than half a century immunological research has been almost exclusively orientated towards the acquired immune response and the mechanisms of immune tolerance. Major discoveries have enabled us to better understand the functioning of the specific immune system: the structure of antibody molecules, the genetic mechanisms leading to the molecular diversity of B (BCR) and T (TCR) lymphocyte antigen receptors, the biological function of major histocompatibility complex (MHC) molecules in the presentation of peptides to alpha/beta receptor bearing T lymphocytes, the processes of positive and negative selection of lymphocytes during the course of their differentiation. The major role of specific or acquired immunity has been shown by the rapidly lethal character of severe combined immune deficiency diseases and various alterations in the mechanisms of tolerance have been proposed to explain the chronic inflammatory illnesses which are considered to be auto-immune. Natural or innate immunity has been known since the first description of an inflammatory reaction attributed to Cornelius Celsus. It entered into the scientific era at the end of the 19th century with the discovery of phagocytes by Metchnikoff and of the properties of the complement system by Bordet [1] but due to the vastness of the field and its lack of clear definition, it failed to excite the interest of researchers. The discovery of cytokines and progress in knowledge of the mechanisms of the inflammatory reaction have certainly helped to banish preconceived ideas about natural immunity, which was wrongly labelled as non-specific. This has led to the proposition of a wider role for immune functions beyond the level of the cell or the organism [2] and to a better understanding of the importance of the immediate defence mechanisms and their role in the later orientation of the acquired response.

Complement System Proteins↗
PubMed1992

Immunization and vaccination protocol in hemodialysis patients with naturally acquired hepatitis B antibody.

Long-term behavior of naturally acquired anti-HBs antibody was tested every 6 months for 3 years in 22 dialysis patients. Fifteen of them maintained protective levels throughout follow-up (102 and 85.5 mUI/ml at the beginning and the end, respectively). Seven of them became anti-HBs and were submitted to a 40-micrograms booster injection of hepatitis B vaccine. Seroconversion was observed in 6 of 7 patients (85.7%) with a mean anti-HBs titer of 90.4 and 47.3 mUI/ml after 3 and 6 months, respectively. Protective anti-HBs level may be maintained longer in patients with natural immunity than in HBsAg-negative vaccinated subjects. Effectiveness of a reduced vaccination protocol in patients who have lost their natural immunization should be confirmed with further studies.

Adult↗
PubMed1977

[Alteration of the natural humoral immunity in experimental diphtheritic infection induced by different doses of the agent].

The authors carried out a complex study of natural humoral immunity factors in rabbits experimentally infected with various doses of diphtheria bacillus (500, 200, 100, 50 and 1 million, 10 000 and 1000 microorganisms). Natural protection factors--the complement, properdin, and lysozyme proved to undergo similar dynamic changes with each infection dose. The extent and direction of the changes depended on the infection dose. No significant natural immunity changes were caused by a low dose. A dose of 10 000 microbes caused stimulation of properdin and lysozyme activity. Dose of 1, 5, and 50 million suppressed the activity of all the components, the most pronounced with the later dose. Changes occurring with the doses of 200 and 100 million microbes were phasic in character.

Animals↗
PubMed1997

[The nature of hematopoiesis in animals with experimentally depressed immune system: natural and bifidumbacterin-induced recovery].

An attempt was made to examine the regulatory effect of bifidumbacterin on the recovery of immunological and hemopoietic homeostasis in mice. Bifidumbacterin feeding to healthy animals had no effect, except for the below-normal values reaching the statistically mean characteristic of mice of this strain. Bifidumbacterin stimulated lymphoiesis in animals immunocompromized by the administration of antilymphocytic antibodies or radiation, but the values being no higher than the normal ones. The same action was seen with erythropoiesis during postradiation loss of red blood cells. The activation or suppression of erythro- or myelopoiesis, which was not caused by direct damage to these cellular populations, but which occurred with the activation of nonspecific T helpers or T suppressors in impairments or recovery of the count of circulating mature lymphocytes under the action of bifidumbacterin, was blocked.

Animals↗
PubMedDate not supplied

Tissue types as prognostic risk factor in hepatitis B virus infection.

OBJECTIVES: Outcome after acute hepatitis B virus (HBV) infection may be determined by the host immune system. We studied the distribution of major histocompatibility (MHC) antigens in patients who developed natural immunity against HBV and those with chronic hepatitis B. METHODS: Thirty patients positive for IgG anti-HBs and anti-HBc ('naturally immune'), 30 patients with HBsAg-positive chronic hepatitis and 30 subjects with no serological markers of HBV infection (controls) were studied. MHC class-I antigens were detected by the standard Terasaki microlymphocytotoxicity test and the MHC class-II antigens by a polymerase chain reaction using sequence-specific primers. RESULTS: In the naturally immune group, A11, B73, CW3, DRB1*16 and DQB1*05 antigens were significantly more frequent than in the control group, and B73, DRB1*04 and DRB1*13 antigens were more frequent than in the chronic hepatitis group. In the chronic hepatitis group, CW6, DRB5 and DQB1*05 antigens were significantly more frequent than in the control group, and B8, CW7, DRB1*03 and DQB1*02 antigens were more frequent than in the naturally immune group. CONCLUSIONS: Differences in alleleic frequencies of HLA among persons with natural immunity against HBV and those with chronic hepatitis B may suggest a genetic basis for persistence of HBV infection and occurrence of chronic liver disease.

Adult↗