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PubMedDate not supplied

Genealogical memory to perinatal iodine-131 exposure in rats: I. Alteration in natural immunity.

A heritable alteration in the natural immunity as measured by changes in the natural killer (NK) cell activities of peripheral blood lymphoid-cells was found to occur in rats upon an in utero exposure to iodine-131. The model that was employed for the measurements consisted of Fischer F344 inbred rats exposed to iodine-131 (sodium) during their 16th to 18th day of gestation. The natural immunity of the animals was evaluated by determining the NK cell activities of peripheral blood lymphoid cells of the offsprings when they reached 2 months of age. Immediately following determination of the natural immunity, brother and sister matings were carried out for evolution of the families. Study of these pedigrees revealed an impairment in the natural immunity to persist through two generations (F1, and F2) of the male animals. The hematological profiles of the animals suggest that the insult may alter the numbers of red and white blood cells in the succeeding generations, but has little noticeable effect upon the percentage of lymphocytes. The interpretation of the results indicate that a perinatal insult by iodine-131 during late gestation can result in both somatic and germ cell changes in the immunological system. Thus, there appears to be a genealogical memory to an in utero radionuclide insult which may adversely affect the offspring's immunological competency to respond to subsequent insults.

Animals↗
PubMed1978

Neutralizing and hemagglutination-inhibiting antibodies to rubella virus as indicators of protective immunity in vaccinees and naturally immune individuals.

In general, hemagglutination-inhibiting (HAI) and neutralizing (NT) antibodies to rubella virus tend to parallel one another, and the presence of either antibody has been interpreted as reflecting protective immunity. It has recently been shown that persons who have HAI antibody but lack NT antibody may be subject to reinfection. In the present study these two antibodies were compared with regard to their appearance and persistence in vaccines and in those who have experienced natural infection. NT antibody appeared more slowly following immunization with HPV77DE5 or Cendehill vaccines than after natural infection or immunization with RA 27/3 vaccine. As with natural infection, initial NT antibody responses to RA 27/3 vaccine were of higher titer and persisted at higher levels for three years than was the case with either of the other vaccines. NT testing procedures were found to differ in sensitivity, depending on several factors including the cells in which the virus was grown.

Adult↗
PubMed2000

Natural immunity and neuroimmune host defense.

Innate resistance is mediated by non-immune defense and by natural immunity. Non-immune defense includes diverse mechanisms (e.g., physico-chemical defense by bile acids). Natural killer (NK) cells, gamma delta T lymphocytes and CD5+ B lymphocytes are key mediators of natural immunity. These cells utilize germ-line coded receptors that recognize highly conserved, homologous epitopes (homotopes). Typically, it is not the antigen, but cytokines and hormones that regulate the level of NK-mediated cytotoxicity. These include interleukin-2, interferons, prolactin and growth hormone. Less is known about gamma delta T lymphocytes. CD5+ B lymphocytes produce germ-line coded antibodies (predominantly IgM) that are polyspecific, and able to recognize a great variety of microorganisms, cancer-cells and self-components. Antigen is not an effective stimulus for natural antibody (NAb), but bacterial lipopolysaccharide (LPS) is. During the acute phase response (febrile illness) the T-cell-regulated adaptive immune response is switched off and natural immune mechanisms are amplified several hundred to a thousand times within 24-48 hours (immunoconversion). This immunoconversion is initiated by immune-derived cytokines, and involves profound neuroendocrine and metabolic changes, all in the interest of host defense. Immune recognition is assured by natural antibodies and by some liver-derived acute phase proteins, such as C-reactive protein or endotoxin-binding protein, the level of which is elevated in the serum. Thus, natural immunity is essential for a first and last line of defense and the neuroendocrine system is an important promoter of this activity.

Animals↗
PubMed1997

Characterization of immune response to Eimeria tenella antigens in a natural immunity model with hosts which differ serologically at the B locus of the major histocompatibility complex.

A model to simulate natural immunity to Eimeria tenella was developed in three chicken lines which differ at the B locus of the major histocompatibility complex. Homozygous, 1-day-old chicks of the B19B19, B24B24, or B30B30 genotype were trickle immunized by being orally fed a small infectious dose of E. tenella oocysts for 5 consecutive days. These naturally exposed birds were then challenged at different times between 5 and 24 days after the final dose, and the level of protection was assessed 6 days after challenge, using body weight gain and intestinal lesion scores. The duration of immunity in naturally exposed birds differed among the major histocompatibility complex lines. Trickle immunization of the B19B19 haplotype afforded the longest and strongest level of protection compared to the other two haplotypes tested. In addition, in vitro splenic and peripheral blood lymphocyte proliferative responses in trickle-immunized birds were measured against sporozoite, merozoite, and tissue culture-derived E. tenella parasite antigens isolated from the recently described SB-CEV-1/F7 established cell line. The lymphocytes obtained from B19B19 birds trickle immunized responded in vitro to the E. tenella-infected SB-CEV-1/F7 tissue culture-derived parasite antigen. Furthermore, antigen-specific immune responses appeared earlier in immune, challenged B19B19 birds than in their naive, challenged counterparts. The development of a model simulating natural immunization will serve as a foundation to further characterize both humoral and cell-mediated responses to E. tenella tissue culture-derived parasite antigens and to better understand host protective immune responses to avian coccidiosis.

Animals↗
PubMed1998

Neuroimmunoregulation and natural immunity.

The development and function of the immune system is regulated by neuroendocrine factors. Immune function may be divided into adaptive and natural immunity. Adaptive immune responses are driven by specific determinants of the antigen (epitopes), require 5-10 d to fully develop, and show an accelerated or memory response after repeated exposure to the same antigen. Natural immunity may be divided into host defense mediated by non-immune factors (e.g., antimicrobial proteins, enzymes, mucus etc.) and polyspecific responses of the immune system. This polyspecific response relies on natural antibodies and on some other serum proteins (e.g., lipopolysaccharide-binding protein-LBP, C-reactive protein-CRP), and on surface receptors of macrophages, natural killer cells and B and T lymphocytes for activation. Highly conserved homologous (crossreactive) epitopes, or homotopes for short, are recognized by the natural immune system. Natural antibodies, LBP, and CRP are capable of activating the entire immune system after combination with the appropriate homotope. During febrile illness natural immune host defense is promptly elevated because of the rapid rise of natural antibodies, LBP, and CRP in the serum. This is known as the acute phase response (APR), which is initiated by a sudden rise of cytokines in the circulation, such as IL-1, IL-6, and TNF-alpha. The cytokines act on the brain, the neuroendocrine system, and on other tissues and organs, which leads to fever and profound hormonal and metabolic changes. The hypothalamus-pituitary adrenal axis is activated and serves as the primary regulator of immune and inflammatory reactions. Insulin, glucagon, and catecholeamine levels are also raised. Bone marrow activity and leukocyte function are high and the liver is converted to the rapid production of acute-phase proteins (APP). APP include LBP, CRP, fibrinogen, some complement components, enzyme inhibitors, and anti-inflammatory proteins, which may rise in the serum from several hundred to a thousand times within 24-48 hr. Therefore, natural immunity is a polyspecific response to homotopes, which functions as an instantaneous defense mechanism in health and which is rapidly boosted by cytokines and hormones during febrile illness. This is a highly successful defense reaction, as in the overwhelming majority of cases, febrile illness leads to recovery and the development of adaptive immunity in man and higher animals.

Acute-Phase Reaction↗
PubMed1969

Human immunity to the meningococcus. II. Development of natural immunity.

Results of the present study suggest that natural immunity to meningococcal disease is initiated, reinforced, and broadened by intermittent carriage of different strains of meningococci throughout life. In young adults, carriage of meningococci in the nasopharynx is an efficient process of immune sensitization. 92% of carriers of serogroup B, C, or Bo meningococci were found to develop increased titers of serum bactericidal activity to their own meningococcal isolate, and 87% developed bactericidal activity to heterologous strains of pathogenic meningococci. The rise in bactericidal titer occurred within 2 wk of onset of the carrier state, and was accompanied by an increase in titer of specific IgG, IgM, and IgA antibodies to meningococci. In early childhood, when few children have antibodies to pathogenic meningococci, active immunization seems to occur as a result of carriage of atypical, nonpathogenic strains. Immunity to systemic meningococcal infection among infants in the neonatal period is associated with the passive transfer of IgG antibodies from mother to fetus. The antigenic determinants which initiate the immune response to meningococci include the group-specific C polysaccharide, cross-reactive antigens, and type-specific antigens.

Adolescent↗
PubMedDate not supplied

[Effect of excess-protein rations on natural immunity indices].

Some parameters of natural immunity under conditions of the diets with optimal (18%) and excessive (28,33 and 43% by caloric value) protein content were studied in male Wistar rats. It was shown that a number of the parameters studied (the content of complement, lysozyme, beta-lysines, the normal antibody titer, phagocytic activity of leukocytes, skin bactericidal action) decreased with the elevation of the protein content in the diets 3 months after the beginning of the experiment. The bactericidal activity of the blood serum in all the animal groups remained unchanged. The animals kept on diets with 18 and 43% of protein for prolonged period of time were examined 6, 9 and 12 months after the beginning of the experiment. The parameters of natural immunity (except the content of complement and beta-lysines) in the group of animals receiving 43% of protein remained decreased as compared with the control.

Animals↗
PubMed1994

Natural immunity in breast cancer patients during neoadjuvant chemotherapy and after surgery.

Breast cancer is the most common cancer in women. Surgery, and more recently neoadjuvant chemotherapy, are being utilized as the initial treatment for breast cancer; however little is known about their effects on the natural immune system. The natural immune system (natural killer [NK] cells) is thought to be important in immune surveillance, including protection from metastasis during the intravascular tumour seeding that occurs during surgery. To investigate the effects of surgery on the natural immune system, we studied the pre-operative and post-operative peripheral blood lymphocytes (PBL) of 10 patients with stage I or II breast cancer: there was a 71.6 +/- 25.3% post-operative reduction in NK cell function (P < 0.005, Student's paired t-test). To investigate the effects of neoadjuvant chemotherapy and surgery, we examined PBL from five patients with stage III breast cancer: NK cell function dropped 95.7 +/- 1.9% after neoadjuvant chemotherapy, and there was a further 51.0 +/- 23.4% decrease after surgery (P < 0.05, Student's paired t-test). Neither group of patients had decreased numbers of NK cells, changes in the percentage of T helper or suppressor cells, or alterations in the production of cytotoxic factor by NK cells. These findings suggest that the impairment in NK cell function reflects a defect in the ability of NK cells to recognize and/or bind to tumour target cells. We conclude that the initial treatment of breast cancer patients, whether it involves surgery alone or with neoadjuvant chemotherapy, profoundly impairs their natural immune system and could increase the risk of metastasis. Further studies are needed to delineate the mechanism of this derangement in natural immunity and possibly alter its course.

Adult↗
PubMed2004

Natural immunity to Haemophilus influenzae type B in children of Ankara, Turkey.

BACKGROUND: Haemophilus influenzae type b (Hib) infection has a high morbidity and mortality rate especially in children under 5 years of age. The incidence of Hib disease in Turkey is not known, and Hib vaccine is not included in the National Immunization Program. The aim of this study was to determine the natural immunity to Hib of children 6-60 months of age living in the Park Health Center region of Ankara, Turkey. METHODS: A total of 270 children were selected by layered random sampling method, and 242 of them (89.6%) participated in the study. A questionnaire was given to the parents of the children who were included in the study and blood samples were taken from those children. Anti-Hib IgG antibody (anti-PRP) level was determined in the serum by using anti-Haemophilus influenzae IgG EIA kit and anti-PRP antibody levels of 0.15 microg/mL and over were accepted as the natural immunity. RESULTS: Natural immunity was determined in 65.3% of the children. A relationship was determined statistically between the history of disease with possible Hib agent and with natural immunity. CONCLUSIONS: The exposure rate of children with Hib was higher than expected, even in children who were just a few months old. Our data revealed that multicentric, national studies should be done to define the burden of Hib disease before making a decision for Hib vaccine to be included in the National Immunization Program.

Antibodies, Bacterial↗
PubMed1975

A heterophile system in human renal transplantation. IV. Natural immunity and its genetic implications.

Natural heterophile immunity was studied in 949 individuals including 41 recipients and donors of renal transplants and 141 families. The prevalence and strength of the natural immunity was at its maximum during the first two decades of life and declined thereafter. The population could be divided into three groups: one with natural immunity to heterophile transplantation antigens (HT-A), one with a heterophile immunity which was not (anti-HT-A) (i.e., anti-HX-A), and one group which had no heterophile immunity. Transplantation among these groups yielded results which along with family studies and mathematical considerations suggest that the HT-A system is controlled by a single genetic locus comprised of one dominant and one recessive allele.

Absorption↗
PubMed1986

Augmentation of natural immunity and correlation with tumor response in melanoma patients treated with human lymphoblastoid interferon.

Thirty-two melanoma patients treated with lymphoblastoid alpha interferon (Wellferon) were studied for augmentation of five putative parameters of natural immunity including natural killing (NK), antibody-dependent cellular cytotoxicity (ADCC), cell-mediated inhibition of growth in culture of a murine tumor (GIA), and the size of the OKTIO+ and Leu 7+ subpopulations of peripheral blood mononuclear cells (OKTIO and Leu7). This study confirms and extends our previous conclusions that interferon increases GIA and OKTIO. The increases occurred at 24 hr after interferon, both early and late in the course of treatment, and were dose dependent. NK, ADCC, and Leu7 were activated in many patients individually and mean values for NK and Leu7 were increased in the population as a whole. Two patients with complete remission showed dramatically increased natural immunity by the parameters studied, but the pattern of increase was very different for each patient. The current study of lymphoblastoid alpha interferon demonstrates the immunomodulatory potential of interferon given to melanoma patients, but it fails to support the hypothesis that augmentation of these parameters of natural immunity by interferon may result in tumor responses.

Antibody-Dependent Cell Cytotoxicity↗
PubMed1981

[Changes in integral indicators of natural immunity in experimental hypo- and hyperthyroidism].

Two natural immunity integral indices-the skin bactericidal action and the blood antibacterial activity-were studied in experimental rat hypo- and hyperthyrosis by means of original radioimmunoassay. A decrease in the skin bactericidal action was seen hypothyrosis, but as whole, this test proved to be insufficiently sensitive. An alteration of the blood antibacterial activity in hypo- and hyperthyrosis is characterized by an initial increase in this activity, followed by its lowering. The prolonged phase of the blood antibacterial activity growth was found in hyperthyrosis, whereas in hypothyrosis the decreased phase of the above activity was seen. The pronounced changes in the natural immunity level precede clinical manifestations of the thyroid affection. Radioimmunoassay is recommended for studying the blood antibacterial activity as a sensitive and informative test, allowing one to judge of the antibacterial immunity state.

Animals↗
PubMed1990

The in vivo biologic effect of interleukin 2 and interferon alfa on natural immunity in patients with head and neck cancer.

Given the association of deficient natural immunity with the risk of metastatic disease, the ability to activate natural killer cell function may have a therapeutic significance. The effect of continuous infusion of interleukin 2 plus intramuscular interferon alfa on natural immune status was, therefore, analyzed in eight patients with head and neck cancer. Also evaluated was the effect of interleukin 2-interferon alfa therapy on lymphokine-activated killer cell activity as well as total lymphocyte count, percent of lymphocyte subsets, and levels of both circulating immune complexes and antibody classes. Both the percent and absolute number of natural killer cells (ie, CD56+ CD3- lymphocytes) within peripheral blood as well as natural killer cell activity against K562 targets increased significantly with treatment. The remaining immune parameters were not significantly altered. The demonstrated capacity to modulate natural immune function supports the potential use of interleukin 2-containing regimens as a preventive measure against metastatic disease in patients with head and neck cancer.

Adult↗
PubMed1979

[Natural immunity in destructive appendicitis in children].

The activity of natural immunity factors in appendicitis reached its maximum in the period from 24 till 48 hours and then decreased. In most patients with low level of natural immunity preoperative clinical manifestations were less pronounced, the postoperation period being inactive.

Adolescent↗
PubMed1989

[Natural immunity in patients with type 1 diabetes mellitus].

Combined use of immunological (marking of different lymphocyte populations with monoclonal antibodies, their quantitation and isolation as a concentrate by flow cytometry) and cytological (electron microscopy and ultrastructural lymphocyte and monocyte cytochemistry) methodologies revealed a lowered non-specific immunity, particularly in the natural killer cells system and monocytic line cells, in the majority of diabetes mellitus patients. The revealed changes explain the increased susceptibility to and aggravated course of viral, bacterial, fungal, and certain malignant diseases in IDDM patients. In addition to insulin therapy, stimulation of natural immunity with immunomodulators is recommended for these patients.

Diabetes Mellitus, Type 1↗
PubMed1994

Exercise, natural immunity, and tumor metastasis.

Exercise has been shown to reduce the growth of primary tumors and to enhance certain aspects of host natural immunity. The question of whether these are independent phenomena or are casually related has not been systematically evaluated. This paper presents information concerning the methodological difficulties in studying proposed relationships between exercise and cancer, focusing specifically on tumor metastasis, the process by which malignant cells disseminate to distant organs and establish new colonies. This paper also focuses on how natural immune processes and tumor cells exert bidirectional influences on each other. It is suggested that the direction of the impact of exercise on the control of metastatic spread of neoplastic cells will reflect, in part, the sensitivity of the specific tumor to cytolysis by natural immune mechanisms, the route of dissemination, the timing of exercise relative to tumor exposure, and whether exercise acts as a distress or eustress state.

Animals↗
PubMed1977

Role of urinary solutes in natural immunity to gonorrhea.

Natural resistance of the male urethra to gonococci has not been explained by classical immune mechanisms but could result from antibacterial properties of urine. Accordingly, we measured survival in midmorning urine of 10(7) F-62 T2 gonococci per ml by serial dilutions and plate counts. Fifteen killer urines from eight people all killed greater than 3 logs (average, 5.3), and 13 of 15 were sterilized. Fourteen nonkiller (inhibitor) urines from seven subjects allowed no growth. Killer urines were more acidic (pH 5.4 versus 6.4) and more concentrated (861 versus 717 mosmol/kg) than nonkillers. Upon addition of hydrogen ion, urea, and sodium chloride to urines and broth, pH proved to be the major killing factor, but urea and NaCl were also bactericidal. Susceptibility to urine bactericidal power did not vary with colony type (T2 versus T4) or strain (F-62 versus two fresh isolates). Killing was rapid (0.5 to 3 h) and not bacteriolytic. Escherichia coli multiplied 10-fold in urines that inhibited growth of gonococci. Thus, the bacteriostatic effect of urine may explain why gonococci do not infect the bladder and kidney during gonorrhea. The bactericidal properties of urine may contribute to resistance against gonococcal urethritis.

Bacteriolysis↗