BackgroundNatural cytotoxicity, mediated by natural killer (NK) cells plays an important role in the inhibition and elimination of malignant tumor cells. To investigate the immunoregulatory role of NK cells and their potential as diagnostic markers, NK cell activity (NKA) was analyzed in prostate cancer (PCa) patients with particular focus on NK cell subset distribution.MethodsProspective data of NKA and NK cell subset distribution patterns were measured from 51 patients initially diagnosed with PCa and 54 healthy controls. NKA was represented by IFN-γ levels after stimulation of the peripheral blood with Promoca®. To determine the distribution of NK cell subsets, PBMCs were stained with fluorochrome-conjugated monoclonal antibodies. Then, CD16+CD56dim and CD16−CD56bright cells gated on CD56+CD3− cells were analyzed using a flow-cytometer.ResultsNKA and the proportion of CD56bright cells were significantly lower in PCa patients compared to controls (430.9 pg/ml vs. 975.2 pg/ml and 2.3% vs. 3.8%, respectively; p<0.001). Both tended to gradually decrease according to cancer stage progression (p for trend = 0.001). A significantly higher CD56dim-to-CD56bright cell ratio was observed in PCa patients (41.8 vs. 30.3; p<0.001) along with a gradual increase according to cancer stage progression (p for trend = 0.001), implying a significant reduction of CD56bright cells in relation to the alteration of CD56dim cells. The sensitivity and the specificity of NKA regarding PCa detection were 72% and 74%, respectively (best cut-off value at 530.9 pg/ml, AUC = 0.786).ConclusionsReduction of CD56bright cells may precede NK cell dysfunction, leading to impaired cytotoxicity against PCa cells. These observations may explain one of the mechanisms behind NK cell dysfunction observed in PCa microenvironment and lend support to the development of future cancer immunotherapeutic strategies.

Salmonella organisms are gram-negative and facultative anaerobic bacteria that cause typhoid fever in humans. In this study, we evaluated LPS-specific adaptive immunity in innate immune-deficient mice after oral administration of attenuated S. enterica serovar Typhymurium (S. Typhimurium) strains. Of interest, identical levels of LPS-specific IgG and IgA antibodies were elicited in the systemic (i.e., serum and spleen) and mucosal (i.e., fecal extract and small intestine) compartments of wild-type, TLR4−/−, and MyD88−/− mice following oral vaccination with recombinant attenuated S. Typhimurium (RASV). Depletion of CD4+ T cells during RASV vaccination completely abrogated the generation of LPS-specific antibodies in MyD88−/− mice. In addition, mRNA expression levels of a B-cell activating factor of the TNF family (BAFF) were significantly increased in the spleens of MyD88−/− mice after oral administration, implying that T cell–independent B cell switching might be also enhanced in the MyD88 signal-deficient condition. Of most interest, orally vaccinated MyD88−/− mice that possessed high levels of LPS-specific IgG and IgA, which had neutralizing effect against Salmonella, died earlier than non-vaccinated wild-type mice following lethal oral challenge with virulent Salmonella species. These results suggest that innate immunity mediated by MyD88 signal is dispensable for induction of LPS-specific antibody responses following oral administration of attenuated Salmonella strains but indispensable for efficient protection.

Toll-like receptors (TLRs) directly induce innate host defense responses, but the mechanisms of TLR-mediated adaptive immunity remain subject to debate. In this study, we clarified a role of TLR-mediated innate immunity for induction of adaptive immunity by oral vaccination with a live recombinant attenuated Salmonella enteric serovar typhimurium vaccine (RASV) strain expressing Streptococcus pneumoniae surface protein A (PspA) antigen. Of note, oral or intranasal vaccination with RASV expressing PspA resulted in identical or even significantly higher levels of PspA-specific IgG and IgA responses in the systemic and mucosal compartments of MyD88−/− mice of either BALB/c or C57BL/6 background when compared with those of wild-type mice. Although PspA-specific CD4+ T cell proliferation in the MyD88−/− mice was minimal, depletion of CD4+ T cells abolished PspA-specific IgG and IgA responses in the MyD88−/− mice of BALB/c background. Of most interest, MyD88−/− mice that possessed high levels of PspA-specific IgG and IgA responses but minimal levels of CD4+ T cell responses died earlier than non-vaccinated and vaccinated wild-type mice following intravenous or intranasal challenge with virulent S. pneumoniae. Taken together, these results suggest that innate immunity activated by MyD88 signals might not be necessary for antigen-specific antibody induction in both systemic and mucosal sites but is critical for protection following oral vaccination with attenuated Salmonella expressing PspA.

Background: Chitinase 3-like 1 protein (CHI3L1) (YKL-40 in humans and breast regression protein [BRP]-39 in mice) is required for optimal allergen sensitization and Th2 inflammation in various chronic inflammatory diseases including asthma. However, the role of CHI3L1 in airway inflammation induced by respiratory viruses has not been investigated. The aim of this study was to investigate the relationship between CHI3L1 and airway inflammation caused by respiratory syncytial virus (RSV) infection. Methods:We measured YKL-40 levels in human nasopharyngeal aspirate (NPA) from hospitalized children presenting with acute respiratory symptoms. Wild-type (WT) and BRP-39 knockout (KO) C57BL/6 mice were inoculated with live RSV (A2 strain). Bronchoalveolar lavage fluid and lung tissue samples were obtained on day 7 after inoculation to assess lung inflammation, airway reactivity, and expression of cytokines and BRP-39. Results:In human subjects, YKL-40 and IL-13 levels in NPA were higher in children with RSV infection than in control subjects. Expression of BRP-39 and Th2 cytokines, IL-13 in particular, was increased following RSV infection in mice. Airway inflammation caused by RSV infection was reduced in BRP-39 KO mice as compared to WT mice. Th2 cytokine levels were not increased in the lungs of RSV-infected BRP-39 KO mice. BRP-39 regulated M2 macrophage activation in RSV-infected mice. Additionally, treatment with anti-CHI3L1 antibody attenuated airway inflammation and Th2 cytokine production in RSV-infected WT mice. Conclusion:These findings suggest that CHI3L1 could contribute to airway inflammation induced by RSV infection. CHI3L1 could be a potential therapeutic candidate for attenuating Th2-associated immunopathology during RSV infection. K E Y W O R D Sbronchiolitis, chitinase 3-like 1 protein, lower respiratory tract infection, respiratory syncytial viruses, type 2 immunity

This study demonstrates that pH1N1 infection directly induces transient asthmatic symptoms in patients regardless of their medical history. pH1N1 infection was shown to stimulate the rapid development of AHR and Th2-type cytokine secretion in mice via the activation of ILC2; it may be activated independently of adaptive immunity.

ALCAM contributes to OVA-induced allergic asthma by stimulating T-cell activation and proliferation, suggesting it as a potential therapeutic target for allergic asthma.

Hyperhidrosis is a disorder that is characterized by the production of excess amounts of sweat. The botulinum neurotoxin A (BoNT/A) has been used to treat hyperhidrosis through multiple intradermal injections at the site of the condition. However, because of BoNT/A toxicity, it is important to precisely deliver the proper dose of the toxin to the target site. In addition, the use of a conventional hypodermic needle for multiple injections in the palm makes the approach undesirable and painful. Here, we designed a BoNT/A-coated microneedle (BoNT-MN) array and tested its efficacy as a substitute pain-free method to treat hyperhidrosis. BoNT-MNs were prepared by coating polylactic acid microneedles with a BoNT/A formulation and were found to successfully penetrate into a thick skin in vitro. The coating formulations were then tested for their stability at 4, 25, and 37 °C for 24 h. BoNT-MNs were found to be much more stable than BoNT/A in a liquid state. Additionally, we carried out in vivo experiments by treating the right paws of mice with BoNT-MNs and found that the treatment induced a significant reduction in the sweating response in the mouse foot pad. Thus, BoNT/A treatment using microneedles is beneficial and may be used as a more efficient and less painful approach to treat hyperhidrosis.

Influenza vaccine-associated anaphylaxis is a very rare allergic reaction to vaccines, but the most concerning and life-threatening adverse reaction. Although the safety of influenza vaccines has been well documented, occasional cases of anaphylaxis in vaccinated patients have been reported. In this study, we analyzed the immunoglobulin E (IgE) response to whole influenza vaccines in a pediatric case of delayed-onset anaphylaxis after influenza vaccination. The patient showed elevated specific IgE levels against whole influenza vaccines, especially with split virion from egg-based manufacturing process. Specific IgE levels to influenza vaccines showed decreased over. We evaluated a causal relationship between influenza vaccine and anaphylaxis event by enzyme-linked immunosorbent assay. Delayedonset anaphylaxis after influenza vaccination can occur in children without predisposing allergic diseases. In addition, the results suggested that formulation and production system of influenza vaccines could affect the probability of severe allergic reaction to vaccines.