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A short summary of the middle ear mucosal defence system and the characteristics of the infecting bacteria associated with purulent acute otitis media (AOM) is given. Data on humoral immune factors in middle ear effusions and serum during AOM are presented and the possibility that children with frequent recurrences of AOM exhibit an impaired ability to produce antibodies against AOM-associated antigens is discussed.
AIM: To construct the recombinant eukaryotic expression vector pCMV-S2. S + 145R(PR) containing mutant HBV s gene and detect the specific humoral immune response to the PR in mice. METHODS: The PR was constructed by positional cloning of restriction endonuclease, and then it was transfected into human hepatocellular carcinoma cell line Hep G2 through electrotransformation. The antigenicity of PR was examined by EIA, ELISA and immunocytochemical staining. The PR and empty vector pcDNA3.0 were then used respectively to immunize intramuscularly 5 C57BL/6 mice, dosage being 100 pg purified plasmid each mouse. The titers of serum anti-HBs and anti-HBs2 antibodies were detected by ELISA. RESULTS: In vitro experiment showed that mutant HBsAg could bind to anti-HBs antibody. The PR could induce anti-HBs and anti-HBs2 antibody production in immunized mice. But the appearance time of serum anti-HBs2 antibody one or two weeks earlier than that of serum anti-HBs antibody. CONCLUSION: The expression product of PR had a good antigenicity, which can induce specific hu-moral immune response in C57BL/6 mice.
In this report we demonstrated that recombinant human interleukin 1 alpha (Il-1) can directly promote generation of helper cells in the humoral immune response to SRBC in vitro from their intrathymic precursors. Using negative elimination of thymocytes by means of monoclonal antibodies directed against thymocyte antigens L3T4, lyt 2 and CD3 with complement, we showed that Il-1 interacted with L3T4-, lyt 2-, CD3- T cell precursors. We found, in addition, that recombinant Il-1 induced in these cells expression of L3T4, lyt 2, CD3 and T cell receptor (TCR). The results presented in this communication are compatible with the view that Il-1 is responsible for the recruitment of functional T cells in the afferent phase of the immune response.
The paper presents the results of serological diagnosis of hemorrhagic fever with renal syndrome (HFRS) and studies of the time course of humoral immunity formation in this disease carried out in 1980-1983 in the Maritime Territory, one of the active HFRS foci.
The development of a malaria vaccine is a priority for improved and sustained malaria control. Optimal use of a vaccine in Africa will only be achieved if it can be delivered through the Expanded Programme of Immunization (EPI). We have completed a trial of the peptide vaccine SPf66 in Tanzanian infants, given alongside the EPI vaccines. This paper describes the humoral responses to SPf66 and the EPI vaccines. A total of 1207 infants were recruited into a two-arm, double-blind, individually randomized placebo-controlled trial of SPf66. The objectives of the trial were to determine the safety, immunogenicity and efficacy of SPf66 and to assess interactions with EPI vaccines when three doses of SPf66 were delivered alongside the EPI vaccines. Cross-sectional surveys were carried out to asses seroconversion rates to the EPI vaccines and the antibody response to SPf66 (NANP)50 and Plasmodium falciparum lysates. Seroconversion rates to EPI vaccines were high and no statistically significant differences in prevalence or titres were found between SPf66 and placebo recipients. IgG antibodies against SPf66 (NANP)50 and whole P. falciparum lysate were present in high titres in mothers of recruited children at the time of birth. Vaccination with SPf66 stimulated a good anti-SPf66 IgG response which declined to preimmunization levels by 2 years of age and which was not associated with protection against clinical malaria. The vaccine induced no IgG antibodies against (NANP)50 or P. falciparum lysates. SPf66 stimulated a humoral immune response when given to very young infants and did not interfere with seroconversion to EPI vaccines. The response to SPf66 was qualitatively different from that seen in older children, in whom SPf66 has been shown to be moderately efficacious. This difference raises concerns about the difficulties of immunizing very young infants who need to be targeted by antimalarial vaccination programs.
BACKGROUND: Immune responses against oxidized low-density lipoprotein (LDL) play an important role in atherosclerosis. The aim of this study was to investigate if humoral immune response against specific oxidized LDL antigens, such as aldehyde-modified peptide sequences of apolipoprotein B-100, reflects disease activity and structure of atherosclerotic plaques. METHODS AND RESULTS: Plaques were obtained from 114 symptomatic subjects referred to carotid endarterectomy and characterized immunohistochemically and histologically. Plasma levels of IgG and IgM against aldehyde-modified apolipoprotein B-100 amino acid sequences 661 to 680, 3136 to 3155 (peptide 210), and 3661 to 3680 (peptide 240) were determined by enzyme-linked immunosorbent assay. High levels of IgG against peptide 210 were associated with increased plaque content of lipids (r=0.24, P<0.05) and hemorrhage (r=0.27, P=0.005), with decreased content of fibrous tissue (r=-0.25, P=0.01), but also with lower total plaque volume (r=-0.21, P<0.05). In contrast, high levels of IgM against peptide 240 were associated with plaques with more fibrous tissue (r=0.35, P<0.001), less lipids (r=-0.34, P<0.001), and less macrophages (r=-0.24, P<0.05). IgM against peptide 210 were found to be associated with plaque fibrous tissue (r=0.20, P<0.05), less lipids (r=-0.21, P<0.05), and less macrophages (r=-0.27, P=0.01). CONCLUSIONS: These findings support the notion that immune responses against oxidized LDL epitopes are involved in atherosclerosis and that the level of circulating antibodies against these structures may reflect disease activity in the arterial wall.
The kinetics of anti-paternal alloantibody production in syngeneically and allogeneically mated mice previously immunized with allogenic spleen cells has been investigated. In allogeneically mated females, total and cytotoxic alloantibody levels increased during the final 3 days of pregnancy to reach maximal levels around 1 week after parturition. The properties of this alloantibody were indistinguishable from those of alloantibody induced by conventional immunization procedures. In syngeneically mated females no increase was observed. Total hysterectomy demonstrated that the immunogenicity of the conceptus required to produce a secondary humoral immune response was initiated in the majority of females between days 9 and 10 of pregnancy, and that the antigenic exposure by day 10 was sufficient to induce a maximal secondary response. These observations were consistent with the time of appearance of serologically demonstrable H-2 antigens on embryonic cells during pregnancy. These phenomena occurred in 'responder' and 'non-responder' female strains (referring to the ability of allogeneically mated females to produce anti-paternal alloantibody during normal pregnancy) demonstrating that they do not differ in their ability to produce a secondary immune response to alloantigens presented via the intrauterine route. The findings are discussed in relation to the nature of the immunogenic stimulus from the concepts in this system and during pregnancy.
In 183 patients with chronic pyelonephritis as unspecific humoral immune parameters CH50E, CB50E, C3, C4 and lysozyme as well as the indirect phagocytosis against Staphylococcus aureus SG 511 and E. coli were tested. Clinically a differentiation according to 3 degrees of the renal function and 3 degrees of the activity of the disease was performed. The statistical analysis took into consideration mean and limit values. With the help of contingency tables tendency pictures were developed. C3, C4 and lysozyme proved as suitable for a humoral immunogramme in chronic pyelonephritis. C3 was increased in clear activity, C4 and lysozyme in restricted renal function and expressed activity. In view of the high biologic variation of humoral test parameters advantages and disadvantages of an immunogramme are discussed. But for patients with chronic pyelonephritis finally the estimations of IgM, IgG, IgD, C3, C4 and lysozyme are regarded as clinically useful. A feasable immunologic test set should be controlled, precised and completed.
Leptospirosis is an emerging zoonosis caused by pathogenic spirochetes belonging to the genus Leptospira. An understanding of leptospiral protein expression regulation is needed to develop new immunoprotective and serodiagnostic strategies. We used the humoral immune response during human leptospirosis as a reporter of protein antigens expressed during infection. Qualitative and quantitative immunoblot analysis was performed using sera from 105 patients from Brazil and Barbados. Sera from patients with other diseases and healthy individuals were evaluated as controls. Seven proteins, p76, p62, p48, p45, p41, p37, and p32, were identified as targets of the humoral response during natural infection. In both acute and convalescent phases of illness, antibodies to lipopolysaccharide were predominantly immunoglobulin M (IgM) while antibodies to proteins were exclusively IgG. Anti-p32 reactivity had the greatest sensitivity and specificity: positive reactions were observed in 37 and 84% of acute- and convalescent-phase sera, respectively, while only 5% of community control individuals demonstrated positive reactions. Six immunodominant antigens were expressed by all pathogenic leptospiral strains tested; only p37 was inconsistently expressed. Two-dimensional immunoblots identified four of the seven infection-associated antigens as being previously characterized proteins: LipL32 (the major outer membrane lipoprotein), LipL41 (a surface-exposed outer membrane lipoprotein), and heat shock proteins GroEL and DnaK. Fractionation studies demonstrated LipL32 and LipL41 reactivity in the outer membrane fraction and GroEL and DnaK in the cytoplasmic fraction, while p37 appeared to be a soluble periplasmic protein. Most of the other immunodominant proteins, including p48 and p45, were localized to the inner membrane. These findings indicate that leptospiral proteins recognized during natural infection are potentially useful for serodiagnosis and may serve as targets for vaccine design.
Using unfixed mouse bladder tumor cells (MBT) as target cells and a modified avidin-biotin-complex (ABC) method made it possible to detect a humoral immune response in C3H mice with growing MBT tumors. The rise of the serum levels is significant (p less than 0.005) when compared to control animals and correlates with the tumor size. Mice with recurrences after surgical removal of the primary tumor had significantly (p less than 0.05) higher serum values than animals without recurrence. Purulent or granulomatous inflammatory changes, muscle necrosis, growth of a lymphoma or an ovarian carcinoma did not significantly change the results (p less than 0.05). Injection of myeloma cells from a different strain of mice caused a minimal, but significant increase in the values when compared to controls (p less than 0.0001). However, the slope of the curve differed significantly (p less than 0.05) from that in mice with MBT tumors. Irradiated MBT cells or Corynebacterium parvum used as immunomodulators significantly increased the serum values (p less than 0.001). In the presence of a growing MBT tumor, however, the immunomodulation did not substantially falsify the results. The serum values were related to the corresponding tumor sizes.
The effects of 14-day treatment with low doses of O,S,S-trimethyl phosphorodithioate (OSS-TMP), an impurity in technical malathion, on the generation of cell-mediated and humoral immune responses were examined in female C57BL/6 mice. At a dose of 2.0 mg/kg per day OSS-TMP, the generation of antibody-secreting cells to sheep red blood cells, the generation of cytotoxic T lymphocytes (CTL) to alloantigen and the production of Interleukin-2 were elevated approximately 2-3 fold, while no changes were observed in the proliferative responses to the polyclonal activators, Concanavalin A, lipopolysaccharide, or phytohemagglutinin. In contrast, at 5.0 mg/kg per day OSS-TMP, both the CTL and specific antibody responses were suppressed, while all other immune parameters examined were unchanged. Data from cell separation and reconstitution experiments indicated that both T and B lymphocytes were affected by these treatment regimes. These data suggest that long-term exposure to low doses of OSS-TMP may enhance the ability of an animal to generate an immune response while higher doses of OSS-TMP may suppress the generation of an immune response.
In a cross-sectional house-to-house study in a leishmaniasis-endemic area in Kenya, the cellular and humoral immune response to Leishmania lipophosphoglycan (LPG) was determined. Clinical data, peripheral blood mononuclear cells, and plasma were obtained from 50 individuals over the age of eight years. Lymphoproliferation and interferon-gamma (IFN-gamma) production by these cells were examined. It was shown that cells from all six individuals in the population with a history of kala-azar responded to LPG in the lymphocyte proliferation assay, and four of these six responded in the IFN-gamma assay. In contrast, cells from 12 of 44 individuals from the study area with no history of kala-azar and none of the five Danish control samples responded to LPG. Antibodies against LPG were detected by enzyme-linked immunosorbent assay in 45 of 50 plasma samples. Our findings clearly show that mononuclear cells from kala-azar patients cured of infection were able to respond to the LPG preparation. The finding of a specific cellular immune response to LPG in 12 of 44 individuals with no history of kala-azar is consistent with previous epidemiologic studies, in which it has been shown that a proportion of L. donovani infections run a subclinical course. The high frequency of individuals with antibodies against LPG might indicate that a majority of the population had been exposed to the parasite.(ABSTRACT TRUNCATED AT 250 WORDS)
Twelve month old female BDF1 mice were exposed to cadmium chloride in the drinking water at concentrations ranging from 0 to 50 micrograms/mL cadmium for 26 days. The humoral immune response against sheep red blood cells, a T-lymphocyte dependent response, was evaluated during the last five days of the exposure period. The antibody response was not suppressed by cadmium exposure (P = 0.661). Weight gains (P = 0.205) and water consumption (P = 0.378) during the exposure period were also unaffected. These results indicate that the immunosuppressive effects of cadmium which have been documented in younger, more immunologically competent mice were masked by the natural age-related immunosuppression that was observed in this study. Immunotoxicological investigations in aged animal models appear to be a poor indicator of immune dysfunction in the general population.
The murine model of actinomycetoma offers the potential of studying many unknown aspects of this infection. In this work, the model was used to investigate the temporal humoral immune response to actinomycetoma agents. Groups of 7- to 9-week-old female BALB/c mice were inoculated in one of the hind footpads with one of four different Nocardia strains. To mimic the constant exposure of infected humans to the virulent soil inhabiting agents, a second injection consisting of live nocardiae in incomplete Freund's adjuvant was administered five months after the first one. Murine serum samples were collected throughout the study and their IgM and IgM titers were determined by ELISA and the Western blot assay. The results obtained indicate that the ELISA titers increased as the infection progressed and this correlated with a greater number of antigen bands being recognized in the blots. Overall, however, the ELISA titers were lower for the N. brasiliensis infected mice than those of the N. asteroides ones. This observation may be indicative of an immunosuppressive state and is worthy of further investigation.
Recombinant human adenoviruses (hAd) have become widely used as tools to achieve efficient gene transfer. However, successful application of hAd-derived vectors in clinical trials is limited due to immunological and potential safety problems inherent in their human origin. In this study, we describe a recombinant ovine adenovirus (OAV) as an alternative vector for gene transfer in vivo. In contrast to an hAd vector, the OAV vector was not neutralized by human sera. An OAV vector which contained the cDNA of the human alpha1-antitrypsin (hAAT) gene linked to the Rous sarcoma virus promoter was generated and administered systemically to mice. The level and duration of hAAT gene expression was similar to that achieved with an hAd counterpart in both immunocompetent and immunodeficient mice. However, the tissue distribution of the OAV vector differed from that observed for hAd vectors in that the liver was not the dominant target. Significantly, we demonstrated efficient gene transfer with the OAV vector into mice immunized with hAd vectors and vice versa. We also confirm that the immune response to a transgene product can prevent its functional expression following sequential application of a vector. Our results suggest a possible solution to endemic humoral immunity against currently used hAd vectors and should therefore have an impact on the design of improved gene therapy protocols utilizing adenovirus vectors.
A lymphocyte transformation microassay was used to study cell-mediated immune (CMI) responses in chickens following inoculation with live infectious bronchitis virus vaccines H 120 and H 52 and challenge with Massachusetts-41 (M-41). Humoral immunity was monitored for comparison, using haemagglutination inhibition (HI) microassay. Specific stimulation of infectious bronchitis virus sensitised lymphocytes was demonstrated by their lack of response to Mycoplasma synoviae and Newcastle disease virus antigens. Positive infectious bronchitis virus stimulation indices appeared before HI titres and ranged from 2.0 to 7.1 over a period of five to 33 days after primary vaccination with H 120. Revaccination with H 52 produced a strong secondary HI response and a relatively weak CMI response. Challenge of vaccinated and revaccinated birds also resulted in strong HI and weaker CMI secondary responses but the more pronounced CMI responses were in the revaccinated-challenged group. There was no correlation between CMI and HI antibody production but a negative correlation was demonstrated between peak CMI responses after vaccination and severity of clinical symptoms after subsequent challenge.
A lymphocyte transformation microassay was used to study cell mediated immunity (CMI) in chickens following primary and secondary vaccination with inactivated oil emulsion infectious bronchitis (IB) vaccine and subsequent challenge with Massachusetts-41 (M-41). Humoral immunity was monitored for comparison, using the haemagglutination inhibition (HI) microassay. Positive stimulation indices (2 to 2.7 after primary and 2 to 4.8 after secondary vaccination) were lower and HI titres were higher than those previously reported following primary and secondary vaccination with live IB vaccines. The highest HI titres appeared in birds which had received the inactivated vaccine as a secondary vaccination. Challenge of vaccinated and revaccinated birds resulted in strong HI and weak CMI secondary responses. There was no correlation between CMI and HI antibody production. Monitoring egg production and clinical signs showed that a high level of protection against challenge resulted from revaccination with an inactivated oil adjuvant vaccine.
The early phases of the rejection of xenografts exchanged between closely related species are dominated by a vigorous humoral immune response. We have recently used a linker-mediated polymerase chain reaction (LM-PCR) to generate Ig heavy and light chain-specific cDNA libraries to examine the Ig gene control of a prototypic IgM monoclonal antibody, HAR-1, that causes the hyperacute rejection of hamster xenografts. Recombinant clones from the library were screened directly from bacterial colonies by PCR and the nucleic acid sequences of the clones established. Our results demonstrate that the HAR-1 hybridoma is encoded by Ig VH and JH genes in a germline configuration. Comparison of the cDNA sequence for HAR-1 VH with the germline equivalent of this gene isolated from newborn LEW liver (provisionally designated VHHAR-1) showed that the two VH sequences share a nucleic acid identity of 99.3%. Similarly, the HAR-1 monoclonal uses a Ig JH gene that is 98.2% identical with the JH1 nucleic acid sequence available in the GeneBank. The use of Ig VH and JH genes in a germline configuration is similar to that seen with polyreactive natural antibodies to infectious agents and autoantibodies. These humoral responses are thought to be the result of the stimulation of a T cell-independent subset of B cells, the B-1a/B-1b subset, that is responsible for producing antibodies that serve as a primitive humoral (natural antibody) defense mechanism against infectious diseases. Our results suggest that the humoral component of the rejection of xenografts in the hamster-to-rat model may represent the stimulation of this type of B cell antibody response by xenogeneic target antigens that share antigenic epitopes with bacteria and other infectious agents.