PubMed Health⌕ Search

SEARCH · PubMed Health

Results for “Immunity, Humoral”

Explore indexed PubMed citations for clinical trials, systematic reviews and public health research. Read source abstracts and follow each citation to its original PubMed record.

Quote a phrase for an exact phrase match. Source license links do not imply unrestricted reuse.

At least 793 records · Page 44Linked to original sources
PubMed2006

Profiling the humoral immune response in colon cancer patients: diagnostic antigens from Streptococcus bovis.

The human bowel contains a large and dynamic bacterial population that is not only essential for intestinal health, but also critical for the development of diseases such as cancer. In this respect, the Gram-positive bacterium Streptococcus bovis has been associated with colon cancer for many years. To investigate the clinical importance of this association, an immunocapture mass spectrometry assay was developed that can generate infection-related protein profiles. The composition of these profiles is governed by the capture of specific antigens by serum antibodies from colon cancer patients. This assay showed that S. bovis antigen profiles could distinguish 11 out of 12 colon cancer patients from 8 control subjects, whereas antigen profiles derived from the gut bacterium Escherichia coli were not diagnostic for colon cancer. Moreover, S. bovis antigen profiles were also detected in polyp patients, indicating that infection with this bacterium does occur early during carcinogenesis. Highly accurate tandem mass spectrometry was used to identify one of the diagnostic antigens as a surface-exposed heparin-binding protein, which might be involved in attachment of S. bovis to tumor cells. Together, these findings corroborate the hypothesis that colonic lesions provide a specific niche for S. bovis, resulting in tumor-associated "silent" infections. These infections, however, only become apparent in colon cancer patients with a compromised immune system (bacteremia) or coincidental cardiac valve lesions (endocarditis). This makes profiling of the humoral immune response against "silent" S. bovis infections a promising diagnostic tool for the early detection of human colon cancer, which is crucial for the effective treatment of this disease.

Antibody Formation↗
PubMed1976

[Humoral immune reactions on the hepatocellular plasma membrane in the experimental chronic active hepatitis in rabbits (author's transl)].

For the induction of experimental chronic active hepatitis (CAH) in rabbits long term immunization was performed with human liver-specific protein plus complete Freunds adjuvants. Serum antibodies against allogeneic hepatocellular membrane antigens could be detected after 23 weeks using isolated normal rabbit hepatocytes or by the passive hemagglutination technique with liver-specific membrane protein as antigen. Isolated hepatocytes from these rabbits showed in vivo fixed IgG on their plasma membranes in a linear and granular fluorescence pattern. Furthermore immune complexes (Raji-cell test) were detectable in the sera of these animals. After 23 weeks 3 out of 16 animals had developed a chronic active hepatitis (CAH). After 44 weeks 10 of 15 animals and after 78 weeks 6 of 7 surviving animals had a CAH. All these 7 animals had serum antibodies against membrane antigens of isolated rabbit hepatocytes and in vivo fixed IgG on their hepatocellular plasma membranes. The results suggest the existence of autoantibodies against hepatocellular membrane antigens. In addition, immune complexes may be bound to the plasma membranes. The pathogenetic role of these humoral immune reactions has yet to be determined.

Animals↗
PubMed1985

Ontogeny of the invertebrate humoral immune response: studies on various developmental stages of the American cockroach (Periplaneta americana).

Earlier studies revealed that a specific adaptive humoral immune response can be induced in the American cockroach (Periplaneta americana) to the soluble protein complex, Honeybee venom (HBT). We have undertaken a series of ontogenetic studies to determine if there are differences between the protective responses of roaches representing different developmental stages. Our results indicated that the response to HBT in the immature cockroach (nymphs weighing 200-500 mg) was characterized by a significant lag period before immune protection began to develop. However, by the second week of the response, reactivity was comparable to that of the adult. Old adult male roaches (animals 5 months into adulthood) displayed a significant decline in reactivity during the early phases of the response in comparison to younger adults, and in general, appeared to be less vigorous in generating protection. Both the nymph and old adult roaches demonstrated good secondary responsiveness. The results from these experiments indicated that the developmental stage of the roach could be directly correlated to the degree of immunocompetency possessed by the animal. This is similar to the ontogenetic sequence typically found for immune reactivity in vertebrates.

Age Factors↗
PubMed2006

IC31, a novel adjuvant signaling via TLR9, induces potent cellular and humoral immune responses.

IC31, the combination of a novel immunostimulatory oligodeoxynucleotide containing deoxy-Inosine/deoxy-Cytosine (ODN1a) and the antimicrobial peptide KLKL(5)KLK, represents a promising novel adjuvant signaling via the TLR9/MyD88-dependent pathway of the innate immune system. In mice, IC31 induces potent peptide-specific type 1 cellular immune responses, as well as mainly type 1 dominated protein-specific cellular and humoral immune responses. In addition, cytotoxic T lymphocytes were induced, able to kill efficiently target cells in vivo. Activation of murine dendritic cells by IC31 induced efficiently proliferation of naïve CD4(+) TCR transgenic T cells (DO.11.10) as well as their differentiation into IFN-gamma- and IL-4-producing T cells in vitro.

Adaptor Proteins, Signal Transducing↗
PubMed2006

Cross-reactive cellular and humoral immune responses to Salmonella enterica serovars Typhimurium and Enteritidis are associated with protection to heterologous re-challenge.

Chickens infected with Salmonella enterica serovars Typhimurium (ST) and Enteritidis (SE) still represent a major source of human food poisoning via consumption of contaminated meat and eggs. Vaccination represents a sustainable approach to control Salmonella in the chicken and the serovar specificity of immunity has the potential to impact on the need for multivalent vaccines. The issue of cross-reactive immune responses and cross-serovar protection was examined in these experiments. Cellular and humoral immune responses were measured by antigen-specific ELISA and splenocyte proliferation assays during primary infections (with ST and SE) and during a second challenge with homologous or heterologous serovars. Primary infection with ST or SE induced strong lymphocyte proliferation and high levels of specific antibody (IgM, IgG and IgA) responses with substantial serovar cross-reactivity. The occurrence of high levels of splenocyte proliferation and strong antibody responses corresponded to the initiation of clearance with both ST and SE. Re-challenge of ST and SE infection-primed chickens with either serovar resulted in significant levels of protection (assessed by bacterial numbers and rate of clearance) with little difference between homologous or heterologous challenge schedules. Relatively low levels of antigen-specific splenocyte proliferation were detected during secondary infection, which may be caused by splenic T cells exiting to the gut. In contrast, the more rapid specific antibody responses (compared with primary infection controls) indicate the development of a secondary antigen-specific adaptive response. The substantial level of cross-protection between serovars and the level of antigenic cross-reactivity indicates the potential for single serovar live vaccines to protect against both group B and D salmonellae.

Animals↗
PubMed2004

Humoral immune response to native eukaryotic prion protein correlates with anti-prion protection.

Prion diseases are characterized by the deposition of an abnormal form (termed PrP(Sc)) of the cellular prion protein (PrP(C)). Because antibodies to PrP(C) can antagonize deposition of PrP(Sc) in cultured cells and mice, they may be useful for anti-prion therapy. However, induction of protective anti-prion immune responses in WT animals may be hindered by host tolerance. Here, we studied the cellular and molecular basis of tolerance to PrP(C). Immunization of Prnp(o/o) mice with bacterially expressed PrP (PrP(REC)) resulted in vigorous humoral immune responses to PrP(REC) and native cell-surface PrP(C). Instead, WT mice yielded antibodies that failed to recognize native PrP(C) despite immunoreactivity with PrP(REC), even after immunization with PrP-PrP polyprotein and/or upon administration of anti-OX40 antibodies. Consequently, immunized WT mice experienced insignificantly delayed prion pathogenesis upon peripheral prion challenge. Anti-PrP immune responses in Prnp(o/o) mice were completely abrogated by transgenic expression of PrP(C) in B cells, T cells, neurons, or hepatocytes, but only moderately reduced by expression in myelinating cells, despite additional thymic Prnp transcription in each case. We conclude that tolerance to PrP(C) can coexist with immunoreactivity to PrP(REC) and does not depend on thymic PrP(C) expression. Its circumvention might represent an important step toward the development of effective anti-prion immunotherapy.

Animals↗
PubMed1999

Familial resemblance in humoral immune response to defined and crude Schistosoma mansoni antigens in an endemic area in Brazil.

This study addressed whether the humoral immune response to crude and defined Schistosoma mansoni antigens aggregates within families. The sample included 155 siblings from 42 nuclear families in Brazil. Sera examined by ELISA for antibody isotypes reactive to defined schistosome antigens and crude schistosome antigens (soluble adult worm antigen preparation and soluble egg antigen) demonstrated that there was a difference in sibling-pair correlations between defined and crude S. mansoni antigens. In contrast to the finding with crude antigens, egg-positive sibling pairs showed significant familial resemblance for all IgG subclasses and IgE to adult-stage antigens Smp20.8 and Smp50. Only the IgE and IgG4 isotypes showed familial resemblance to the egg-stage antigen, Smp40. Egg-negative sibling pairs showed significant familial resemblance only for IgE and IgG4 to Smp40. That both the IgE and IgG4 response to defined S. mansoni antigens showed familial resemblance is interesting in light of the converging evidence for the role of IgE and IgG4 in human susceptibility and resistance to reinfection.

Adolescent↗
PubMed1981

Specific cellular and humoral immunity after immunization with live Towne strain cytomegalovirus vaccine.

Cytomegalovirus-specific lymphocyte proliferation and immunofluorescent antibody responses were measured serially in five normal adults and eight candidates for renal transplant immunized with Towne strain cytomegalovirus vaccine. All of the normal adults developed cellular and humoral immune responses. Five of the eight immunized renal transplant candidates developed proliferative responses comparable to those of normal adults, although in two instances maximal responses were delayed. Vaccinees developed proliferative responses to antigens prepared from the Towne strain as well as heterologous strains of cytomegalovirus. The appearance of immunofluorescent antibodies was generally delayed for the renal transplant candidates, and two of the individuals who had poor proliferative responses also had low antibody titers.

Antibody Formation↗
PubMed1983

The influence of ethionine-supplemented soy protein diet on cell-mediated and humoral immunity.

These studies were designed to investigate the influence of ethionine, a suspected carcinogen, on cell-mediated (CMI) and humoral immunity. It is believed that ethionine, an analog of methionine which is produced by intestinal bacteria, could have significant relevance to health. To study the effect of ethionine on immune responsiveness, three groups of mice were allowed to feed ad libitum for 5 weeks on one of the following regimens: diet 1, a basal diet of 16% soy protein; diet 2, soy protein supplemented with 0.6% dl-methionine; and diet 3, soy protein supplemented with 0.1% dl-ethionine. The immunological parameters measured were responsiveness to mitogens, [phytohemagglutinin (PHA), concanavalin A (Con A), pokeweed mitogen (PWM), and lipopolysaccharide (LPS)], delayed-type hypersensitivity (DTH) to dinitrofluorobenzene (DNFB), and antibody formation to sheep red blood cells (SRBC). There were no significant differences in mitogen and antigen responses in mice maintained on diets 1 and 2 as measured by thymidine uptake in proliferating lymphocytes. However, there was a significant suppression in mitogen responsiveness in mice that received diet 3. DTH was also suppressed in mice on diet 3. Antibody levels were similar in all groups. Thus, there was clear evidence of suppression of CMI by ethionine in these studies.

Animals↗
PubMed2006

Fiber and penton base capsid modifications yield diminished adenovirus type 5 transduction and proinflammatory gene expression with retention of antigen-specific humoral immunity.

Fiber and penton base capsid proteins of adenovirus type 5 (Ad5) mediate a well-characterized two-step entry pathway in permissive tissue culture cell lines. Fiber binds with high affinity to the cell surface coxsackievirus-and-adenovirus receptor (CAR), and penton base facilitates viral internalization by binding alphav integrins through an RGD motif. In vivo, the entry pathway is complicated by interactions of capsid proteins with additional cell surface molecules and blood factors. When administered systemically in mice, adenovirus vectors (Adv) localize primarily to hepatic tissue, resulting in efficient gene transduction and potent activation of the host antiviral immune response. The goal of the present study was to detarget Adv uptake through fiber and penton base capsid protein manipulations and determine how detargeted vectors influence transduction efficiency, inflammatory activation, and activation of the adaptive arm of the immune system. By manipulating fiber and the penton base, we have generated highly detargeted vectors (up to 1,200-fold reduction in transgene expression in vivo) with reduced macrophage stimulatory activity in vitro and in vivo. In spite of the diminished transduction and macrophage activation, the detargeted vectors induce strong neutralizing immunity as well as efficient antitransgene antibody. Three of the modified vectors produce antitransgene humoral immunity at levels that exceed or are equal to that seen with an unmodified Ad5-based vector. The fiber-pseudotyped and penton base constructs with RGD deleted have attributes that could be important enhancements in a number of vaccine applications.

Adenoviridae↗
PubMed2005

Long-term oral administration of ginseng extract modulates humoral immune response and spleen cell functions.

Ginseng radix (Panax ginseng C.A. Meyer) is a popular herbal medicine in Oriental countries. We investigated the effect of long-term oral administration of ginseng extract on the antigen-specific antibody response. Male BALB/c mice were treated orally for 30 consecutive days with 2 g/kg of a 50% ethanol extract of ginseng root. Mice treated with ginseng and immunized with ovalbumin (OVA), resulting in an eight-fold increase in titers of anti-OVA immunoglobulin (Ig)G in the serum compared to the group receiving OVA immunization without ginseng treatment; the level of IgG was also significantly elevated in the mice treated with ginseng and immunized with OVA. Mice treated with ginseng without OVA immunization exhibited significantly reduced IgG and IgA production by spleen cells. However, IgG production was not affected in mice treated with ginseng and OVA immunization in spleen cells. Interleukin (IL)-2, interferon (IFN)-gamma and IL-4 secretion by spleen cells from either ginseng-treated mice or OVA-immunized mice were down-regulated compared to that in the control group; while the production of IL-10 was unchanged. The percentage of CD8+ cells was significantly reduced in spleen cells from ginseng-treated, OVA-immunized mice. Thus, long-term oral administration of ginseng extract appears to potentiate humoral immune response but suppress spleen cell functions.

Administration, Oral↗
PubMed1988

Effect of heptaminol AMP amidate, a new nucleotide derivative, on in vitro humoral immunity.

Heptaminol AMP amidate (HAA), a newly developed derivative of 5'-AMP, was found to potentiate the in vitro primary humoral immune response against T cell-dependent antigen, sheep red blood cells, when HAA was present in the early phase of spleen cell culture. Such a potentiating effect was not found against T cell-independent antigens such as lipopolysaccharide (LPS), trinitrophenylated (TNP)-LPS and TNP-Ficoll. The pattern of HAA-mediated immunopotentiation was similar to that of dibutyryl cyclic AMP. When HAA was added to the culture simultaneously with theophylline and imidazole, the immunopotentiating effect of HAA was further augmented and suppressed, respectively. The present results suggested that HAA-mediated immunopotentiation might be in some way related to the intracellular level of cyclic nucleotides in the early phase of culture.

Adenosine↗
PubMed1989

Anti-myosin humoral immune response following cardiac injury.

A sensitive and highly specific ELISA assay was developed to determine the anti-myosin humoral immune response (AMA) in various heart diseases: acute viral myocarditis, infective endocarditis, acute myocardial infarction, and valve and coronary bypass surgery. The mean study entry AMA titer of each patient group was already significantly increased compared with age matched controls. During further follow-up (90 d) all the groups except for endocarditis showed a significant increase of AMA titer compared with their entry titer. Anti-myosin antibody titer were higher after cardiac surgery than after myocardial infarction or inflammatory heart disease. These results suggest that anti-myosin immune response is not limited to infectious processes in which the pathogen induces antibodies which cross-react with heart constituents but is merely caused by direct cardiac injury. Myosin as a major compound of heart cellular proteins turned out to be a good candidate to trigger immune response after cardiac injury.

Adolescent↗
PubMed1979

Comparative effects of azathioprine, cyclophosphamide and frentizole on humoral immunity in mice.

Data is presented comparing the activities of three immunosuppressive agents, cyclosphosphamide, frentizole and azathioprine in models of humoral immunity in mice. Cyclophosphamide and frentizole suppressed the primary and secondary plaque forming cell responses to sheep erythrocytes at lower doses than did azathioprine. Prolonged suppression of serum antibody titers occurred following short-term therapy with cyclophosphamide or frentizole, but not azathioprine. Azathioprine was also the least effective agent in suppressing a primary response to the T-independent antigen, trinitrophenylated lipopolysaccharide. All three agents were found to inhibit the induction and activity of suppressor cells at immunosuppressive doses.

Animals↗
PubMed1976

[Encephalitis and humoral immunity].

Fourteen children with viral infection of the central nervous system have been examined with respect to their function of humoral immunity. Serum concentrations of immune globulins have been measured and antibody titers determined. Iso- and hetero agglutinins as well as antibodies against diphtheria, pertussis, and tetanus if the children were vaccinated have been measured. Anti viral antibodies were tested if children reported the respective infection in their history. Selective antibody deficiency have been found in three children all of whom had normal serum IgG and two elevated IgM levels. These three children showed complications in the course of infection. Nine children had elevated serum IgM and titers of IgM-antibodies were also in or above the high normal range.

Antibodies↗
PubMed1989

[Basic principles of the humoral immune response].

Lymphocytes carry on their cell surface receptors capable of specifically recognizing substances foreign to the organism. During the humoral immune response these foreign substances bind to the receptors of B lymphocytes and induce these cells to divide, to produce increased amounts of the receptors and to secrete the receptors in the form of soluble immunoglobulins into the extracellular milieu. This process requires the participation of T helper lymphocytes, factors called cytokines and organized microanatomic structures.

Antibody Formation↗
PubMed1989

Effects of a commercial malathion dip preparation on the cellular and humoral immune response of BALB/c mice.

Because of the widespread use of malathion as a treatment for ectoparasitism, a study was undertaken to determine the effects of a malathion dip preparation on the BALB/c mouse immune system. Mice were treated with either 2% (recommended dosage) or 8% solutions of malathion or a water control. The cellular immune response was evaluated by in vitro exposure of lymphocytes to mitogens, and the humoral immune response was assessed by using an enzyme-linked immunosorbent assay (ELISA) to quantify antibody production against sheep red blood cells (SRBC). Responses to the mitogens and to the SRBC were not significantly different between 2% and 8% malathion treated and water treated mice. Results indicated that malathion did not affect these two aspects of the mouse immune system when used as a 2% or 8% dipping solution.

Analysis of Variance↗