Protection against Streptococcus pneumoniae lung infection after nasopharyngeal colonization requires both humoral and cellular immune responses

Streptococcus pneumoniae is a common cause of pneumonia and infective exacerbations of chronic lung disease, yet there are few data on how adaptive immunity can specifically prevent S. pneumoniae lung infection. We have used a murine model of nasopharyngeal colonization by the serotype 19F S. pneumoniae strain EF3030 followed by lung infection to investigate whether colonization protects against subsequent lung infection and the mechanisms involved. EF3030 colonization induced systemic and local immunoglobulin G against a limited number of S. pneumoniae protein antigens rather than capsular polysaccharide. During lung infection, previously colonized mice had increased early cytokine responses and neutrophil recruitment and reduced bacterial colony-forming units in the lungs and bronchoalveolar lavage fluid compared with control mice. Colonization-induced protection was lost when experiments were repeated in B-cell- or neutrophil-deficient mice. Furthermore, the improved interleukin (IL)-17 response to infection in previously colonized mice was abolished by depletion of CD4+ cells, and prior colonization did not protect against lung infection in mice depleted of CD4+ cells or IL17. Together these data show that naturally acquired protective immunity to S. pneumoniae lung infection requires both humoral and cell-mediated immune responses, providing a template for the design of improved vaccines that can specifically prevent pneumonia or acute bronchitis.     

Independence of measles-specific humoral and cellular immune responses to vaccination

With a larger, independent cohort and more sophisticated measures, we sought to confirm our work that indicated independence of humoral and cellular immunity following measles vaccination. We recruited an age-stratified random cohort of 764 healthy subjects from all socioeconomic strata, all with medical-record documentation of 2 age-appropriate doses of measles-containing vaccine. We quantified measles-specific neutralizing antibody levels and assayed the interferon-γ (IFN-γ) enzyme-linked immunosorbent spot assay (ELISPOT) response to measles virus. We also measured secreted cytokines from the peripheral blood mononuclear cells (PBMCs) in response to measles virus by performing enzyme-linked immunosorbent assays as secondary measures of cellular immune status. The median antibody level and median IFN-γ ELISPOT response were 844 mIU/mL (interquartile range [IQR]: 418-1,752) and 36 (IQR: 13.00-69.00) spot-forming cells (per 2 × 10(5) PBMCs), respectively. We observed only a very weak and negative correlation (Spearman's r(s) or ρ of -0.090 [95% confidence interval: -0.162--0.018]). We observed a similar lack of quantitatively important correlations between the neutralizing antibody level and any of the secondary measures. Our data confirm the independence of humoral and cellular immune responses after the second dose of measles vaccination. As researchers pursue novel measles vaccine and measles vaccine delivery systems, they must not infer that humoral responses predict cellular responses.     

PIKA as an adjuvant enhances specific humoral and cellular immune responses following the vaccination of mice with HBsAg plus PIKA

An adjuvant is usually used to enhance the immune response induced by vaccines. The choice of adjuvant or immune enhancer determines the effectiveness of the immune response. Currently, aluminium （Alum, a generic term for salts of aluminium） is the only FDA-approved adjuvant. Alum predominantly induces the differentiation of Th2 cells and thus mediates an antibody immune response. Therefore, there is an urgent need for new adjuvants that enhance not only humoral but also cellular immune responses. In the present study, we demonstrates that PIKA （a stabilized dsRNA） as an adjuvant directly induces the activation and the proliferation of both B and NK cells in vitro. Injection of PIKA into mice results in the production of cytokines in vivo. In addition, the study demonstrates that PIKA promotes the maturation of bone marrow-derived dendritic cells （BMDCs） including up-regulation of the co-stimulatory molecules CD80, CD86 and CD40, and the induction of cytokines such as IL-12p70, IL-12p40 and IL-6. Importantly, after immunization of mice with HBsAg plus PIKA, the presence of PIKA enhances the titers of HBsAg-specific IgG and HBsAg-specific IFN-γ production. These results demonstrate that PIKA as an adjuvant can promote both humoral and cellular immune responses. These might have an implication in applying PIKA as an adjuvant to be used in the design and development of both therapeutic and preventive vaccines, and used in the clinical study.     

Oral administration of a synthetic agonist of Toll-like receptor 9 potently modulates peanut-induced allergy in mice

BACKGROUND: Agonists of Toll-like receptor 9 have been shown to induce potent T(H)1-type immune responses and prevent and reverse ovalbumin-induced T(H)2-dominant allergic asthma in mice. OBJECTIVE: We examined oral administration of a synthetic agonist of Toll-like receptor 9 (immune modulatory oligonucleotide [IMO]) to modulate peanut-induced allergy in mice. METHODS: In the prevention model mice were sensitized 3 times by means of oral administration of peanut in the presence or absence of IMO. In a treatment protocol mice were sensitized orally with peanut on days 0 and 14 and treated 4 times with oral administration of IMO starting on day 21. RESULTS: In the prevention study mice that received the combination of IMO/peanut showed decreased IgE and increased IgG2a levels in the serum and intestinal tissue compared with mice sensitized with peanut only. In spleen cell recall experiments, production of IL-5 and IL-13 was inhibited and production of IFN-gamma was increased in mice immunized with the peanut/IMO combination compared with those sensitized with peanut only. In the treatment model IMO-treated mice showed decreased IgE, IL-5, and IL-13 levels and increased IgG2a and IFN-gamma levels in the serum, intestines, and spleen cells compared with PBS-treated mice. A reduction in local inflammation and restoration of normal structure in the intestines was found in the mice that received IMO in both models. CONCLUSION: These results indicate that IMOs can switch peanut-induced T(H)2 immune responses toward T(H)1 responses accompanied by reduced inflammation in the gastrointestinal tract and anaphylaxis in both the prevention and treatment models. CLINICAL IMPLICATIONS: IMOs might be suitable candidates for the management of peanut-induced allergy.     

Toll-like receptor 9 modulates immune responses to Aspergillus fumigatus conidia in immunodeficient and allergic mice

The role of Toll-like receptor 9 (TLR9) in antifungal responses in the immunodeficient and allergic host is unclear. We investigated the role of TLR9 in murine models of invasive aspergillosis and fungal asthma. Neutrophil-depleted TLR9 wild-type (TLR9(+/+)) and TLR9-deficient (TLR9(-/-)) mice were challenged with resting or swollen Aspergillus fumigatus conidia and monitored for survival and lung inflammatory responses. The absence of TLR9 delayed, but did not prevent, mortality in immunodeficient mice challenged with resting or swollen conidia compared to TLR9(+/+) mice. In a fungal asthma model, TLR9(+/+) and TLR9(-/-) mice were sensitized to soluble A. fumigatus antigens and challenged with resting or swollen A. fumigatus conidia, and both groups of mice were analyzed prior to and at days 7, 14, and 28 after the conidium challenge. When challenged with resting conidia, TLR9(-/-) mice exhibited significantly lower airway hyper-responsiveness compared to the TLR9(+/+) groups. In contrast, A. fumigatus-sensitized TLR9(-/-) mice exhibited pulmonary fungal growth at days 14 and 28 after challenge with swollen conidia, a finding never observed in their allergic wild-type counterparts. Increased fungal growth in allergic TLR9(-/-) mice correlated with markedly decreased dectin-1 expression in whole lung samples and isolated dendritic cell populations. Further, whole lung levels of interleukin-17 were lower in allergic TLR9(-/-) mice compared to similar TLR9(+/+) mice. Together, these data suggest that TLR9 modulates pulmonary antifungal immune responses to swollen conidia, possibly through the regulation of dectin-1 expression.     

鼻咽癌抗独特型抗体诱导的体液和细胞免疫应答

目的 探讨抗独特抗体２Ｈ４和５Ｄ３模拟抗原诱导免疫应答的能力。方法 用Ａｂ２免疫Ｂａｌｂ／ｃ小鼠获得抗血清,以ＥＬＩＳＡ检测其Ａｂ３,Ｗｅｓｔｅｒｎ Ｂｌｏｔ分析其识别抗原的分子质量。用迟发型超敏反应（ＤＴＨ）和淋巴细胞增殖试验,检测Ａｂ２诱发细胞免疫反应的能力。结果 ２Ｈ４,５Ｄ３免疫同系动物产生的含有抗抗蚀特型抗体（Ａｂ３）的抗血清,可特异性地与靶细胞结合。ＦＣ２（Ａｂｌ）和经２Ｈ４免疫的Ａｂ     

Vasoactive intestinal polypeptide enhances oral tolerance by regulating both cellular and humoral immune responses

Vasoactive intestinal polypeptide (VIP) is an important signal molecule of the neuroendocrine-immune network. In the immune system, VIP has been found to act as an endogenous anti-inflammatory mediator. In the current study, it was found that VIP administration regulated oral tolerance by inhibiting both cellular and humoral responses. Compared with vehicle-treated mice, mice treated with VIP during the development of ovalbumin (OVA)-induced oral tolerance exhibited the least delayed-type hypersensitivity (DTH), showed profoundly reduced proliferative capacity and produced less interferon (IFN)-gamma, interleukin (IL)-6, IL-5, IL-10 and interferon-inducible protein (IP-10). IgA-secreting cells in the gut as well as OVA-specific IgG and other isotypes levels in plasma were inhibited significantly after VIP-treatment. The VPAC2 receptor may be involved in VIP-mediated oral tolerance enhancement. Taken together, these results suggest that VIP enhanced oral tolerance via regulating both cellular and humoral responses.     

Adjuvant effects of orally administered saponins on humoral and cellular immune responses in mice

We have described adjuvant effects of orally administered Quillaja saponins on the immune responses of mice fed inactivated rabies antigen (AG). The in vivo lymphocyte proliferation in mice fed antigen + saponin (AG + SAP) was significantly greater than that in mice fed antigen (AG) alone. Further, the mitogen-induced cell proliferative responses in animals primed with AG + SAP was markedly increased compared with those in the AG group. These changes in clonal expansion were associated with an enhanced helper T cell (Th) and B cell co-operation. The in vivo cell proliferation and in vitro mitogen-induced responses of mice fed AG + SAP correlated with enhanced antibody synthesis. In mice fed saponin alone, there were significant increases in clonal expansion and lymphocyte function. Our present data indicate that the immunocompetence in animals fed AG + SAP was indeed evoked by saponins. Cytotoxic T lymphocyte activity in mice fed SAP or AG + SAP was detected 7 days after booster, in contrast to 21 days in mice fed AG alone. The natural killer cell activity in mice fed SAP alone was greatly enhanced and persisted for an extended period of time.     

A comparison of the humoral and cellular immune responses at different immunological sites after split influenza virus vaccination of mice

The spleen, bone marrow and lymph nodes are all known to be important organs for the initiation and maintenance of an immune response after vaccination. To investigate the differences and similarities in the humoral and cellular immune responses between these tissues, we vaccinated mice once or twice with the conventional human dose (15 microg HA) of influenza A (H3N2) split virus vaccine and analysed the sera and lymphocytes collected from the different sites. We found that the response of antibody secreting cells (ASC) in the lymph nodes appeared to be more transient than in the spleen, possibly because the influenza-specific IgM ASC in particular might have migrated from the lymph nodes immediately after activation. The serum antibody response was found to initially correspond with the ASC response elicited in the spleen and the lymph nodes, whereas the later serum IgG reflected the ASC response in the bone marrow. Proliferation of influenza-specific CD4(+) and CD8(+) cells was predominantly observed in the spleen and was associated with higher concentrations of cytokines than in the lymph nodes. The finding of influenza-specific CD8(+) cell proliferation in the spleen indicates that a split influenza virus vaccine may stimulate a cytotoxic T-cell response. Our results also showed that the primary response elicited a mixed Th1/Th2 profile, whereas the secondary response was skewed towards a Th2 type. Each of the three tissues had a different immunological pattern, suggesting that in preclinical vaccine studies, there is a case for investigating a range of immunological sites.     

A major cell surface antigen of Coccidioides immitis which elicits both humoral and cellular immune responses

Multinucleate parasitic cells (spherules) of Coccidioides immitis isolates produce a membranous outer wall component (SOW) in vitro which has been reported to be reactive with antibody from patients with coccidioidal infection, elicits a potent proliferative response of murine immune T cells, and has immunoprotective capacity in a murine model of coccidioidomycosis. To identify the antigenic components of SOW, the crude wall material was first subjected to Triton X-114 extraction, and a water-soluble fraction derived from this treatment was examined for protein composition and reactivity in humoral and cellular immunoassays. Protein electrophoresis revealed that the aqueous fraction of three different isolates of C. immitis each contained one or two major glycoproteins (SOWgps), distinguished by their molecular sizes, which ranged from 58 to 82 kDa. The SOWgps, however, showed identical N-terminal amino acid sequences, and each was recognized by sera from patients with C. immitis infection. Antibody raised against the purified 58-kDa glycoprotein (SOWgp58) of the Silveira isolate was used for Western blot and immunolocalization analyses. Expression of SOWgp was shown to be parasitic phase specific, and the antigen was localized to the membranous SOW. The water-soluble fraction of SOW and the purified SOWgp58 were tested for the ability to stimulate proliferation of human peripheral monocytic cells (PBMC). The latter were obtained from healthy volunteers with positive skin test reaction to spherulin, a parasitic-phase antigen of C. immitis, and from volunteers who showed no skin test reaction to the same antigen. The SOW preparations stimulated proliferation of PBMC from skin test-positive but not skin test-negative donors, and the activated cells secreted gamma interferon, which is indicative of a T helper 1 pathway of immune response. Results of this study suggest that SOWgp is a major parasitic cell surface-expressed antigen that elicits both humoral and cellular immune responses in patients with coccidioidal infection.     

Nature of immune lymph node factors stimulating humoral and cellular immune responses

Institute of Immunology, Ministry of Health of the USSR, Moscow. (Presented by Academician of the Academy of Medical Sciences of the USSR A. D. Ado.) Translated from Byulleten' Éksperimental'noi Biologii i Meditsiny, Vol. 107, No. 4, pp. 460–462, April, 1989.     

Comparative study of cellular and humoral immunity as well as of resistance to the rabies virus in rabies vaccination

Experiments in CBA and BALB/c mice showed that after vaccination against rabies alongside with humoral immune response there developed a clone of cells sensitized to rabies antigen which, upon a secondary exposure to it, responded by increased blast formation. The immunological memory to the rabies antigen was found to be specific and to persist for up to 100 days (the observation period). Immunization of mice with rabies vaccine using various schedules and in combination with interferon inducers revealed no correlation between the lymphocyte blastogenesis parameters and virus-neutralizing antibody levels or the intensity of immunity to street rabies virus. The lymphocyte blasttransformation test with nonspecific mitogens may also be used for evaluation of the toxicity of new preparations.     

Regulatory effects of osteoprotegerin on cellular and humoral immune responses

The interaction between receptor activator of nuclear factor-kappaB ligand (RANKL) and RANK has been reported to regulate immunity in addition to bone metabolism. The aim of this study was to determine if osteoprotegerin (OPG), an inhibitor of the RANKL-RANK interaction and possibly a new drug against osteoporosis, would adversely affect immunity. OPG was used to treat mice developing different models of cellular and humoral immune responses and also in vitro in T and B cell assays. In mice, OPG does not affect cell-mediated reactions such as contact hypersensitivity to the hapten oxazolone and liver damage, granuloma formation, and infectious load induced by mycobacterial infection. However, OPG increases humoral reactions such as the production of IgM, IgG, and IgE against the T cell dependent antigen keyhole limpet hemocyanin and the production of IgM against the T cell independent antigen Pneumovax. In vitro, OPG modestly co-stimulates T cells but does not affect the proliferation of B cells. OPG has modest immunoregulatory effects that seem to be confined to the humoral response to specific antigens.     

Interrelations of humoral and cellular immune responses in experimental canine gastritis

Experimental canine gastritis is an animal model with features similar to the gastritis of human pernicious anaemia. In this study eight mongrel dogs immunized with autologous or homologous gastric juice in Freund' scomplete adjuvant developed gastritis whereas four mongrel dogs immunized with the adjuvant alone did not. Cellular immunity to gastric juice antigens demonstrated by skin testing and peripheral leucocyte migration inhibition coincided with the appearance of gastritis, whereas parietal cell antibodies appeared some 2 weeks later. The work demonstrates the combined humoral and cellular immune response of the dogs to gastric juice, and suggests that the cellular response may be of primary importance in the development of gastritis.     

Anthrax protective antigen administered by DNA vaccination to distinct subcellular locations potentiates humoral and cellular immune responses

Based on the hypothesis that immune outcome can be influenced by the form of antigen administered and its ability to access various antigen‐processing pathways, we targeted the 63 kDa fragment of protective antigen (PA) of Bacillus anthracis to various subcellular locations by DNA chimeras bearing a set of signal sequences. These targeting signals, namely, lysosome‐associated membrane protein 1 (LAMP1), tissue plasminogen activator (TPA) and ubiquitin, encoded various forms of PA viz. lysosomal, secreted and cytosolic, respectively. Examination of IgG subclass distribution arising as a result of DNA vaccination indicated a higher IgG1:IgG2a ratio whenever the groups were immunized with chimeras bearing TPA, LAMP1 signals alone or when combined together. Importantly, high end‐point titers of IgG antibodies were maintained until 24 wk. It was paralleled by high avidity toxin neutralizing antibodies (TNA) and effective cellular adaptive immunity in the systemic compartment. Anti‐PA and TNA titers of ≈10⁵ and ≈10³, respectively, provided protection to ≈90% of vaccinated animals in the group pTPA‐PA63‐LAMP1. A significant correlation was found between survival percentage and post‐challenge anti‐PA titers and TNA titers. Overall, immune kinetics pointed that differential processing through various compartments gave rise to qualitative differences in the immune response generated by various chimeras.     

Impairment of cellular but not humoral immune responses in chronic pulmonary and disseminated paracoccidioidomycosis in mice.

Humoral and cellular immune responses were measured during the progression of chronic pulmonary and disseminated paracoccidioidomycosis in mice. The chronic disease was established by pulmonary infection of mice with different doses of the yeast form of Paracoccidioides brasiliensis isolate GAP. Levels of antibodies to P. brasiliensis, detected in serum by immunodiffusion and enzyme-linked immunosorbent assay, directly correlated with the size of the infectious challenge. Significant delayed-type hypersensitivity (DTH) responses to antigen were largely restricted to week 1 after pulmonary infection with intranasally administered high doses (5.0 x 10(6) or 1.1 x 10(7) CFU per inoculum). In vitro lymphoproliferative responses of peripheral blood lymphocytes (PBL) to P. brasiliensis antigens were significant only at 2 weeks after infection with intranasally administered 1.1 x 10(7) CFU. Responses of PBL to concanavalin A were depressed (50% of control response) as early as 8 weeks and reached a nadir at 10 to 18 weeks after infection. Infected mice made antibodies to sheep erythrocytes (SRBC) (10(9) intravenously [i.v.]) normally at all times tested after infection. In contrast, infected mice sensitized to SRBC (10(6) i.v.) had significantly depressed DTH responses to SRBC at 9 and 20 weeks postinfection compared with noninfected mice. These results indicated that in this model, normal humoral responses developed to homologous and heterologous antigens. In contrast, the T cellular immune responses were depressed with progression and chronicity of the disease. Thus, this model closely mimics the immunological findings in human paracoccidioidomycosis.     

Defensins act as potent adjuvants that promote cellular and humoral immune responses in mice to a lymphoma idiotype and carrier antigens

Defensins released by neutrophils are able to kill a broad spectrum of microbes. They also induce leukocyte migration in vitro and elicit inflammatory leukocyte responses at s.c. injection sites in mice. In vitro experiments showed that human defensins enhanced concanavalin A-stimulated murine spleen cell proliferation and IFN-gamma production. This led us to examine the effects of human defensins on specific immune responses in vivo. BALB/c mice were immunized with 50 microg of keyhole limpet hemocyanin (KLH) adsorbed to aluminum hydroxide and administered with defensins in aqueous solution. Intraperitoneal administration of defensins significantly increased the production of KLH-specific IgG1, IgG2a and IgG2b antibodies 14 days after immunization. In vitro splenic KLH-specific proliferative responses were higher in mice treated with KLH and defensins than in those treated with KLH alone. Increased IFN-gamma and, to a lesser extent, IL-4 production were also detected in the supernatants of ex vivoKLH-activated spleen cells from mice treated with defensins. Finally, defensins significantly enhanced the antibody response to a syngeneic tumor antigen, lymphoma Ig idiotype and also augmented resistance to tumor challenge. These results indicate that defensins act as potent immune adjuvants by inducing the production of lymphokines, which promote T cell-dependent cellular immunity and antigen-specific Ig production. Thus, defensins appear to function as neutrophil-derived signals that promote adaptive immune responses.     

Comparison of specificities of humoral and cellular immune responses to haptens

In this study we induced humoral and cellular immunity to three isomers of aminosulfanilic and aminobenzoic acids and compared their respective specificities. These studies were facilitated by using a new method for preferentially inducing a cellular immune response to haptens: the haptens were covalently coupled to mycobacteria and injected into animals in incomplete Freund's adjuvant. Humoral antibody was iduced by coupling the same isomers to bovine serum albumin and injecting them into animals in complete Freund's adjuvant. Both groups of animals were examined for hapten-specific cellular immunity (migration inhibition factor, delayed skin tests) and for antibody response (passive hemolysin test). The results show that although both cell-mediated and humoral responses can discriminate the para, meta and ortho isomeric forms of the haptens used, the antibody response demonstrated much less cross-reactivity. The relevance of this finding to different requirements for B and T cells in antigenic recognition is discussed.