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PubMed1979

Organ and isotype distribution of plasma cells producing specific antibody after oral immunization: evidence for a generalized secretory immune system.

Mice were induced to produce IgA antibodies against ferritin after oral immunization. Such antibodies were detected by immunofluorescence in plasma cells in the intestinal mucosa as well as in secretory sites located elsewhere, such as the lactating mammary gland, salivary gland, and respiratory tract. The observation suggested that cells immunized locally via the gut could home to distant secretory sites. To confirm this hypothesis, lymphocyte transfer studies were done with mesenteric node (MN) versus peripheral node (PN) cells from orally immunized donors into nonimmunized recipients. IgA anti-ferritin cells from MN homed to exocrine targets, whereas IgM and IgG anti-ferritin cells homed to PN. The findings overall support the concept of a generalized and interrelated secretory immune system.

Animals↗
PubMed1970

Immunization against neonatal tetanus in New Guinea. 3. The toxin-neutralization test and the response of guinea-pigs to the toxoids as used in the immunization schedules in New Guinea.

The mouse toxin-neutralization test procedure described has been used for antitoxin titration of sera of New Guinea women following primary immunization with plain and adjuvant tetanus toxoids and following booster immunization, and for titration of guinea-pig sera.The responses of guinea-pigs immunized with the same toxoids and immunization schedule to simulate the human field trial studies were observed for 6 months. The relative antitoxin responses of guinea-pigs to the different toxoids were similar to those of the women.

Animals↗
PubMed1979

Bursa of Fabricius--mitotic index in the follicles of immunized and non-immunized chicks (Gallus domesticus).

The mitotic index in the cortical compartment of the follicles of the bursa of Fabricius from chicks immunized with sheep red blood cells (SRBC) is always higher when compaired with non-immunized ones. This mitotic index reachs its maximum 6 days after the SRBC injection, coincident with the highest serum antibody titer. The mitotic activity in the cortex of the follicles of the bursa of Fabricius is always higher than that of the medulla during the postembryonic development of chickens (PROCHAZKA, RODAK, KREJCI 1967). Otherwise it is almost established that the cortex is a zone of continuous lymphocyte proliferation, not occuring the same with the medulla. In addition these bursal histological structures are considered as 2 distinct compartments (GROSSI et al. 1974). The purpose of this paper is to study the response in the mitotic index of the cortical and medullary compartments of the follicles of the bursa of immunized and non-immunized chicks. To correlate possible changes in the mitotic index with circulating antibody levels, the serum antibody titer from the same birds was also recorded.

Animals↗
PubMed1977

Comparison of the immune response in serum and bucco-pharyngeal secretions following immunization by different routes with a live hog cholera virus vaccine (Thiverval strain).

The influence of vaccination route on local and systemic immune response was studied with hog cholera virus vaccine. Kinetics of antibody synthesis in serum and bucco-pharyngeal secretion was observed. Results show that, whatever the vaccination route (intranasal or intramuscular) a good systemic and local immune response were induced and pigs resisted to a virulent challenge. However the highest local immune response was obtained by intranasal vaccination with large vaccine dosage (10(7) P.F.U./pig). After a virulent challenge performed by intranasal route, no clear anamnestic immune response was detected in bucco-pharyngeal secretions.

Administration, Intranasal↗
PubMed1983

Alveolar macrophages in pulmonary immune responses. I. Role in the initiation of primary immune responses and in the selective recruitment of T lymphocytes to the lung.

Antigen inoculated intratracheally (IT) into animals can induce primary immune responses and selectively recruit specific T cells to the lung. In the current study, the role of alveolar macrophages (AM) in these two responses was investigated. Antigen-pulsed bronchoalveolar cells (BAC) inoculated IT into guinea pigs generated a population of immune T cells that proliferated in vitro on reexposure to antigen-pulsed macrophages (Mø). The possibility that antigen-pulsed donor BAC shed antigen that was subsequently processed and presented by host Mø was ruled out by genetic experiments. Thus, peritoneal exudate lymphocytes (PEL) from (2 X 13)F1 guinea pigs primed with antigen-pulsed BAC from strain 2 animals responded preferentially to antigen-pulsed strain 2 Mø rather than to antigen-pulsed strain 13 Mø. In a second set of studies, antigen-pulsed BAC inoculated IT into guinea pigs selectively recruited antigen-specific T cells to the lung. Genetic experiments verified that inoculated BAC were the source of the antigen-presenting cells responsible for selective recruitment. Thus, antigen-pulsed strain 2 BAC inoculated IT recruited a greater proportion of (2 X 13)F1 T cells that recognized antigen in the context of strain 2 Mø than F1 T cells that recognized antigen on strain 13 Mø. Taken together, these studies suggest that AM contribute to the regulation of pulmonary immunity by both inducing T lymphocyte immunity and selectively recruiting specific T cells to the lung.

Animals↗
PubMed1983

In vitro induction of chronic myeloid leukemia associated immune reactivity in normal human lymphocytes by xenogeneic immune RNA.

Peripheral blood lymphocytes from normal human donors were treated with immune RNA (IRNA) prepared from lymphoid tissues of guinea pigs immunized with chronic myeloid leukemia (CML) cells, normal leukocytes (WBCs) and normal bone marrow (BM) cells, in order to study whether IRNA can confer specific immunoreactivity on normal lymphocytes. The IRNA treated lymphocytes were further exposed to solubilized membrane antigens from CML cells, normal WBCs and BM cells in a criss-cross fashion. The migration inhibition factor produced by these lymphocytes was tested in an in vitro leukocyte migration inhibition assay using normal leukocytes. The results indicated that IRNA prepared from guinea pigs immunized with all the three cell types could transfer the immune reactivity to normal cells in response to the respective antigens. The WBC IRNA incubated lymphocytes did not react with BM cell and CML cell antigens. A potent transfer of specific reactivity was shown by CML IRNA. IRNA produced against BM cells and CML cells demonstrated considerable cross reactivity perhaps due to shared immature cell antigens.

Animals↗
PubMed1983

Immune adherence and staphylococcus protein A binding of soluble immune complexes produced by complement activation.

Complement has been shown to affect the solubility of antigen-antibody complexes by two mechanisms: in the first, classical pathway dependent, complement inhibits the formation of the immune precipitate; in the second, alternative pathway dependent, complement reacts with a formed precipitate to bring about its solubilization. The biological properties of complement reacted immune complexes (IC) has been assessed by studying their binding to staphylococcus protein A (SPA) and to human erythrocytes. BSA-anti-BSA complement reacted IC bound to human erythrocytes and to SPA. Complexes generated by solubilization of immune precipitates showed greater immune adherence than complexes held in solution by complement, despite their similar size. Complexes held in solution in a factor D depleted human serum bound more efficiently to erythrocytes than complexes formed in normal serum. These experiments demonstrate that complement reacted IC cannot be regarded as biologically inert and that factors affecting complement function may have important effects on the properties of antigen-antibody complexes.

Antigen-Antibody Complex↗
PubMedDate not supplied

The immune response of the chick following viral vaccinations and immunization with sheep red blood cells.

The effects of viral vaccinations and immunization with sheep red blood cells (SRBC) on the humoral response of pullets were investigated. Pullets were vaccinated with Marek's disease virus, Newcastle disease virus (NDV), infectious bronchitis virus (IBV), and infectious bursal disease virus at appropriate ages used in commercial practice. At seven weeks, the pullets were intramuscularly immunized with SRBC. NDV and IBV antibodies were detected by hemagglutination-inhibition tests. Hemagglutination (HA) titers were established against SRBC. IBV antibody titers were not affected by vaccination or by immunization with SRBC. NDV antibody titers were significantly increased by vaccination and by immunization with SRBC. The SRBC agglutinin response was also positively affected by vaccination. The HA titer increase consisted of a rise in 2-mercaptoethanol (2-ME)-sensitive antibodies and a fall in 2-ME-resistant antibodies.

Animals↗
PubMed1984

Effects of immune complexes on immunity to Plasmodium berghei infection.

The ELISA test titers and RIPA patterns of sera collected from vaccinated and non-vaccinated rats during P. berghei infection were similar. The sera collected just after clearance of parasitemia from the vaccinated rats, but not that from the non-vaccinated rats protected mice in passive protection tests. After precipitation to remove immune complexes, the sera from the non-vaccinated rats also protected mice. Administration of acute phase serum early in the course of infection aggravated parasitemia and delayed recovery from P. berghei infection in rats. Administration of hyperimmune serum early in the course of infection initially reduced parasitemia but then delayed recovery of rats from P. berghei infection. These results suggest that immune complexes may interfere with antibody mediated immunity to P. berghei and may also retard development of the induced immune response.

Animals↗
PubMed1980

Quantitative studies of natural immunity to solid tumours in rats. Persistence of natural immunity throughout reproductive life, and absence of suppressor cells in infant rats.

Consideration of cell-mediated cytotoxicity as an enzyme-substrate reaction provided a theoretical and practical basis for the quantification of natural immunity to solid tumours. The natural cytotoxic activity of spleen cells from normal rats towards cultured target cells from solid tumours, measured in a 6 h chromium release assay, developed between 2 and 5 weeks after birth and, in contrast to previous reports of natural cytotoxicity against lymphoid tumour cells, showed no sign of decline up till at least 22 months of age. Both virgin and breeder (multiparous) females showed equally good maintenance of natural immunity, and the apparent specificity of this natural immunity on a panel of four target cells did not change between 8 weeks and 18 months of age. The low level of natural immunity in infant spleen, and also in adult lymph nodes and thymus, was not caused by suppressor cells but rather by an absence of appropriate effector cells.

Aging↗
PubMed1983

Anaphylatoxin-mediated regulation of the immune response. II. C5a-mediated enhancement of human humoral and T cell-mediated immune responses.

C5a derived from the fifth component of human complement was found to potentiate both specific and non-specific human in vitro humoral immune responses. In addition, C5a is capable of potentiating antigen- and alloantigen-induced T cell proliferative responses. In contrast to these results, C5a was unable to modulate mitogen-induced B and T cell proliferative responses. The carboxyterminal arginine of C5a is not essential in order for C5a to enhance immune responses. C5ades Arg was found to augment the immune response to the level of C5a-mediated enhancement. The serum carboxypeptidase inhibitor, 2-mercaptomethyl-5-quanodinopentanoic acid, which prevents cleavage of the terminal arginine, allowed us to assay the effects of C5a on in vitro immune responses in the presence of serum. Helper T cells are involved in C5a-mediated immuno-potentiation. Substitution of T cells by soluble T cell-replacing factors, (Fc)TRF, rendered lymphocyte cultures refractory to the enhancing properties of C5a.

Adult↗
PubMed1983

Characterization of anti-Fab' antibodies in human sera: identification of soluble immune complexes that contain hidden anti-KLH and blocking anti-immunoglobulins following immunization with keyhole limpet haemocyanin.

After immunization with keyhole limpet haemocyanin (KLH), increased concentrations of anti-KLH and anti-Fab' antibodies (Abs) were demonstrated in sera from 18 of 20 volunteers. In many cases, post-immunization sera contained soluble immune complexes that incorporated both anti-Fab' and 'hidden' or 'blocked' anti-KLH antibodies. The complexes containing hidden anti-KLH and blocking anti-Fab' Abs were not found in pre-immunization sera. The hidden Abs to KLH were revealed by demonstrating increases in anti-KLH activity in sera incubated previously with Fab' fragments, immobilized on plastic microtitre tray wells. Incubation with insoluble Fab' did not influence the quantity of anti-tetanus toxoid (TT) that was detected in these sera. Addition of affinity purified anti-Fab' Abs to samples, previously 'unblocked' by adsorption with immobilized Fab', depressed their anti-KLH activity to levels present before adsorption, but did not change the quantity of Abs to Dermatophytin, Trychophyton, or TT therein. These results suggest that some autoantibodies generically recognized as 'Fab' specific' have properties that are usually considered to be characteristic of autoanti-idiotypes.

Adult↗
PubMed1982

Antitumor immunity induced by hybrid murine tumor cells: requirements for optimal immunization.

Hybrid tumor cells have been evaluated for their ability to induce specific antitumor immunity in inbred female C3H/He mice challenged with the syngeneic BA tumor. Hybrid cells were produced by fusion of BA cells with a BALB/c renal adenocarcinoma, which is hypoxanthine phosphoribosyl transferase-deficient and grows well in culture. Corynebacterium parvum was evaluated as an adjuvant for BA and hybrid cells. The BA tumor was shown to be poorly immunogenic, and four weekly injections of BA cells alone or C. parvum alone did not confer significant immunity. When BA cells and C. parvum were mixed, survival time was prolonged and most mice remained tumor-free. Hybrid cell lines derived from the BA tumor were produced in culture in unlimited quantities and were successfully used as immunogens. The addition of C. parvum to hybrids gave a significant incremental increase in survival when compared to the survival resulting from immunization by hybrids without adjuvant. When hybrids without adjuvant were used, several weekly injections were required for effective immunization. Irradiated and unirradiated hybrids were compared, and it was found that irradiation did not diminish hybrid immunogenicity. The potential problems and advantages of this concept of therapy are discussed.

Adenocarcinoma↗
PubMed1981

[Humoral and cellular immune responses to brain tissue in animals immunized with ADPT and smallpox vaccine].

Experiments on guinea-pigs showed that 3 subcutaneous injections of adsorbed DPT vaccine resulted (on days 7-14 of the experiment) in the accumulation of cells, sensitized to brain extract, in the lymphoid tissue. The production of circulating anticerebral autoantibodies occurred, as revealed by the indirect immunofluorescent method, during the whole time of the experiment (35 days). On days 28-35 of the experiment cellular immune reaction to autologous erythrocytes was detected in the peripheral blood of the immunized animals. The intracardiac injection of smallpox vaccine to the animals resulted in the appearance of lymphoid cells, sensitized to brain extract, on days 3-7 of the experiment, as well as in the appearance of anticerebral autoantibodies, detected by immunofluorescence, which circulated in the blood for 28 days. Cellular immune reaction to autologous erythrocytes in the peripheral blood of the guinea-pigs immunized with smallpox vaccine was registered on days 3-28 of the experiment.

Animals↗
PubMedDate not supplied

Cell-mediated immune responses in patients with recurrent arthritis following rubella immunization.

Six young adult women with recurrent rubella arthritis after HPV-77 DE/5 rubella immunization were studied. Lymphocyte responses to rubella and mumps antigens, and phytohemogglutinin and pokeweed mitogens, were measured in these patients and in 20 immunized hospital employees who did not develop arthritis. All 6 arthritic subjects had pre-immunization hemagglutination inhibition titers of less than 1:8 and their lymphocyte responses to rubella antigen were significantly elevated when compared with those members of the control group with a similar pre-immunization titer of less than 1:8. No significant differences between the 2 groups were found in the other lymphocyte responses.

Adult↗
PubMed1975

Mechanisms of protective immunity in experimental cutaneous leishmaniasis of the guinea-pig. I. Lack of effects of immune lymphocytes and of activated macrophages.

Leishmania enriettii is an obligatory intracellular protozoan parasite which infects guinea-pigs and resides in macrophages. Subcutaneous inoculation produces a skin infection which heals spontaneously and leaves the animal immune to reinfection. Experiments have been performed to explore the mechanisms of parasite destruction in the recovering and immune animal. Using quantitative techniques to assess parasite survival it was found that L. enriettii is not killed in vitro in macrophages from immune guinea-pigs. Inocubation of monolayers of parasitized macrophages with lymphocytes from Leishmania-immune animals had no effect on the intracellular parasites. Finally, macrophages activated to destroy Listeria monocytogenes did not impair intracellular survival of L. enriettii. The possible significance of these findings in explaining the course of infection is discussed.

Animals↗
PubMedDate not supplied

Objective verification of tetanus immune status in an apparently non-immune population.

Patients who are not known to be immunised to tetanus are considered to be non-immune. The appropriate treatment is the commencement of active immunisation with a course of three tetanus toxoid inoculations; if the wound is considered to be tetanus-prone, 250 IU of human anti-tetanus immunoglobulin is given concurrently. This study determined the true immune status of 166 patients who were considered to be non-immune on the basis of the available history. The majority (90 of 166) had protective levels of immunoglobulin (greater than 0.06 IU/ml) and further treatment was not indicated. Only two patients were non-immune. The remainder had protective levels (between 0.01 and 0.06 IU/ml) and required a tetanus toxoid booster.

Aged↗
PubMedDate not supplied

[Pilot program of immunization against viral hepatitis B, integrated in the extended immunization program in Abancay (peru)].

INTRODUCTION: Abancay is located at 2,395 m.a.s.l. in the Peruvian Andean Region. It is a hyperendemic area for Hepatitis B virus (HBV) and hepatitis delta virus (HDV) infection, where 7% of the deaths are caused by acute and chronic hepatitis infections. In 1991, a pilot immunization program against HBV infection was started to control the incidence of VHB-VHD, and as a strategy to improve the EPI coverage in general. METHODS: Vaccination population was programmed to include 1,301 children under 1 year old and 3,488 children between 1-4 years old. A total of 3 doses of DNA recombinant vaccine against HBV per child were administered. The vaccination schedule fit within the EPI immunization schedule. For children under one year old, the program includes: Newborn: BCG, Polio 1, HBV1; 2-month old: Polio 2, DPT1, HBV2; 3-month old: DPT2, Polio 3; 4-month old: polio 4, HBV 3 and; 9 month old: Measles. For children aged between 1 and 4 years old, the program includes: HBV1, HBV2 one month after HBV1, and HBV six months after HBV1. RESULTS: One year after the immunization program started, 1,262 (97.0%) children under one year old and 2,529 (72.5%) between 1-4 years old were immunized. No relevant adverse effects have been reported. There were 8 deaths due to acute respiratory infection and acute diarrhea diseases, which are the main causes of death in this area. One of the objectives achieved was an improvement in the EPI vaccination coverage for children younger than 1 year old, with a DPT coverage of 97.0% in 1991 compared to 63.0% in 1988, 26.9% in 1989, and 61.9% in 1990. CONCLUSION: The inclusion of HVB vaccination in the EPI for a HBV and HDV endemic area improves the total EPI coverage and it is safe an effective.

Child, Preschool↗