DNA adjuvants for potent mucosal immunity

In order to develop safe vaccines for effective mucosal immunity to major pulmonary bacterial infections, one must consider appropriate vaccine antigens (Ags), delivery systems and nontoxic molecular adjuvants. Such vaccine constructs can induce Ag-specific immune responses which provide effective protection from mucosal infections. In particular, it has been shown that adjuvant-based mucosal vaccine preparations are relatively easy to construct by simply mixing the adjuvant with the bacterial Ag, and the resulting vaccine can elicit protective immunity. We have studied DNA-based nasal adjuvants targeting mucosal dendritic cells (DCs) in order to induce Ag-specific mucosal and systemic immune responses that provide essential protection against microbial pathogens which invade our mucosal surfaces. In this review, we initially introduce a plasmid encoding the cDNA of Flt3 ligand (pFL), a molecule which is a growth factor for DCs as an effective adjuvant for mucosal immunity to pneumococcal infections. Next, we discuss the potential of adding unmethylated CpG oligodeoxynucleotide together with pFL together with a pneumococcal Ag for protection from pneumococcal infections. To do this, we have used pneumococcal surface protein A as vaccine for the restoration of mucosal immunity in aging. Further, we have also used our nasal pFL adjuvant system with phosphorylcholine-keyhole limpet hemocyanin (PC-KLH) in pneumococcal vaccine development, to successfully induce complete protection from nasal carriage by Streptococcus pneumoniae. Finally, we discuss the possibility that anti-PC antibodies induced by nasal delivery of pFL plus PC-KLH may play a protective role for prevention of atherogenesis and thus block the subsequent development of cardiovascular disease

Oral-Nasopharyngeal Dendritic Cells Mediate T Cell-Independent IgA Class Switching on B-1 B Cells

Native cholera toxin (nCT) as a nasal adjuvant was shown to elicit increased levels of T-independent S-IgA antibody (Ab) responses through IL-5- IL-5 receptor interactions between CD4+ T cells and IgA+ B-1 B cells in murine submandibular glands (SMGs) and nasal passages (NPs). Here, we further investigate whether oral-nasopharyngeal dendritic cells (DCs) play a central role in the induction of B-1 B cell IgA class switch recombination (CSR) for the enhancement of T cell-independent (TI) mucosal S-IgA Ab responses. High expression levels of activation-induced cytidine deaminase, Iα-Cμ circulation transcripts and Iμ-Cα transcripts were seen on B-1 B cells purified from SMGs and NPs of both TCRβ−/− mice and wild-type mice given nasal trinitrophenyl (TNP)-LPS plus nCT, than in the same tissues of mice given nCT or TNP-LPS alone. Further, DCs from SMGs, NPs and NALT of mice given nasal TNP-LPS plus nCT expressed significantly higher levels of a proliferation-inducing ligand (APRIL) than those in mice given TNP-LPS or nCT alone, whereas the B-1 B cells in SMGs and NPs showed elevated levels of transmembrane activator and calcium modulator cyclophilin ligand interactor (TACI) expression. Interestingly, high frequencies of IgA+ B-1 B cells were induced when peritoneal IgA− IgM+ B cells were stimulated with mucosal DCs from mice given nasal TNP-LPS plus nCT. Taken together, these findings show that nasal nCT plays a key role in the enhancement of mucosal DC-mediated TI IgA CSR by B-1 B cells through their interactions with APRIL and TACI

The Quaternary Kurobegawa Granite: an example of a deeply dissected resurgent pluton

H.I thank M. Yukawa for her help with sample preparation and LA-ICP-MS data collection, and Y. Hirata for sampling. U-Pb ages were calculated using an Excel spreadsheet provided by S. Sakata. English was improved by M. Coble. Comments by O. Bachmann, J. Wotzlaw and an anonymous reviewer were helpful to improve the manuscript. The Kansai Electric Power Co., Inc., and the Japan Ministry of the Environment gave us permission for the sampling. This work was partly supported by JSPS KAKENHI Grant Number JP16K05617. AC acknowledges the research grant "Beca Puente" and the financial support of a "Plan Propio" grant from the University of Granada Vicerrectorate of Research and Transfer. This is the IBERSIMS publication n. 88.The Quaternary Kurobegawa Granite, central Japan, is not only the youngest known granitic pluton exposed on the Earth’s surface, it is one of few localities where both Quaternary volcanics and related plutons are well exposed. Here, we present new zircon U–Pb ages together with whole rock and mineral geochemical data, revealing that the Kurobegawa Granite is a resurgent pluton that was emplaced following the caldera-forming eruption of the Jiigatake Volcanics at 1.55 ± 0.09 Ma. Following the eruption, the remnant magma chamber progressively cooled forming the voluminous Kurobegawa pluton in the upper crust (~ 6 km depth) until ~ 0.7 Ma when resurgence caused rapid uplift and erosion in the region. This is the first study to document the detailed spatiotemporal evolution of resurgent pluton for a Quaternary caldera system. Our new findings may contribute significantly to understanding the fate of active caldera systems that can produce supereruptions.Ministry of Education, Culture, Sports, Science and Technology, Japan (MEXT) Japan Society for the Promotion of Science Grants-in-Aid for Scientific Research (KAKENHI) JP16K05617University of Granada Vicerrectorate of Research and Transfe

Direct Evidence that 4ʼ-O-methylpyridoxine Induces Hyperactivity and Convulsions due to Pyridoxal Phosphate Deficiency in the Brain

Ginkgo biloba seed (GBS) poisoning is caused by the toxic substance 4’-O-methylpyridoxine (MPN). Gammaaminobutyric acid (GABA) in the brain is suggested to be involved in the convulsion-inducing effect of MPN. 　　To clarify the direct effects of MPN in the brain on behavior and changes in vitamin B6 and GABA concentration, we intrathecally administered MPN (5-80 nmol) to mice. Some of them developed hyperactivity and seizures. Incidence of behavioral abnormalities were correlated with the MPN dose/body weight. In the analysis of the brain, mice with hyperactivity shown decreased Pyridoxal-5’-phosphate (PLP) and decreased GABA/Glutamae (Glu) ratio. Administered MPN dose/body weight was negatively correlated with PLP (p＜0.001) and GABA/ Glu ratio (p＝0.004) in the brain. MPN concentration in the brain negatively correlated with PLP (p＜0.001) and GABA/Glu ratio (p＜0.001), and a positive correlation between concentration of MPN and phosphorylated MPN (4’-O-methylpyridoxine-5’-phosphate, MPNP) was found (p＝0.01). We report for the first time that MPNP is produced from MPN in vivo and MPN decreases PLP concentrations in the brain, resulting in the decrease of GABA/Glu ratio and this change leads to behavioral changes.Article信州医学雑誌 72(3) : 159-167, (2024)journal articl

Two‐sided influence of dupilumab on alopecia areata co‐existing with severe atopic dermatitis: A case series and literature review

Abstract Objectives Alopecia areata (AA) often coexists with atopic dermatitis (AD). Recently, several reports suggested that dupilumab, an interleukin 4 receptor α‐antagonist, administration could be a promising medication not only for severe AD but also for AA concomitant with AD (AD‐AA). At the same time, dupilumab has also been reported to exacerbate AA in AD‐AA cases. Thus, the efficacy of dupilumab on AA in AD‐AA cases remains controversial. Methods In this study, we retrospectively analyzed four AD‐AA cases treated with dupilumab to evaluate its influence on AD and AA. Results All cases had suffered from severe AD since childhood and their average eczema area and severity index (EASI) scores prior to dupilumab administration was 43.2 ± 15.0. Three of four cases had moderate to severe multifocal AA, which successfully recovered in response to dupilumab, accompanied by the decrease in serum thymus and activation‐regulated chemokine (TARC) levels and significant improvement of AD, achieving approximately 90% improvement of EASI scores within 3 months. In contrast, the remaining one case developed rapidly progressive hair loss 8 months after the initiation of dupilumab. In this case, AD was incompletely controlled by dupilumab with the elevation of serum TARC level despite AD improvement. The literature review found 39 dupilumab‐treated AD‐AA cases with elaborate description of clinical course; 24 cases with AA improvement, 15 cases with AA exacerbation, or new onset. Conclusions These findings alert physicians that use of dupilumab in expectation of AA improvement in AD‐AA cases can lead to unfortunate consequence in some patients

Elicitation of Mucosal Immunity by Proteins of Streptococcus pneumoniae

Pneumococcal diseases such as otitis media, pneumonia, and meningitis are invariably preceded by nasopharyngeal colonization, and herd immunity against pneumococcal disease requires protection against colonization. An early study in mice demonstrated that mucosal immunization with cholera toxin B subunit as adjuvant could elicit solid mucosal immunity. Recent data from several laboratories provides support for three different mechanisms by which adaptive immunity can provide protection against colonization. (1) IL- 17- dependent T cell immunity can recruit PMN to sites of colonization. This IL- 17- dependent immunity can be elicited by immunization with antigen plus a mucosal adjuvant, or can be elicited by colonization itself. (2) Immunity against colonization can be mediated by mucosal IgA and at the mucosal surface passive mucosal IgA antibody provides much better protection against carriage than passive IgG antibody. (3) Complement- fixing IgG antibody can protect against colonization and may act by protecting against colonization of bacteri

Nasal Administration of Cholera Toxin as a Mucosal Adjuvant Damages the Olfactory System in Mice

<div><p>Cholera toxin (CT) induces severe diarrhea in humans but acts as an adjuvant to enhance immune responses to vaccines when administered orally. Nasally administered CT also acts as an adjuvant, but CT and CT derivatives, including the B subunit of CT (CTB), are taken up from the olfactory epithelium and transported to the olfactory bulbs and therefore may be toxic to the central nervous system. To assess the toxicity, we investigated whether nasally administered CT or CT derivatives impair the olfactory system. In mice, nasal administration of CT, but not CTB or a non-toxic CT derivative, reduced the expression of olfactory marker protein (OMP) in the olfactory epithelium and olfactory bulbs and impaired odor responses, as determined with behavioral tests and optical imaging. Thus, nasally administered CT, like orally administered CT, is toxic and damages the olfactory system in mice. However, CTB and a non-toxic CT derivative, do not damage the olfactory system. The optical imaging we used here will be useful for assessing the safety of nasal vaccines and adjuvants during their development for human use and CT can be used as a positive control in this test.</p></div

Habituation–dishabituation test after nasal administration of 30 μg CTB or CT.

<p>One day (24 h, <b>A</b>) or three days (72 h, <b>B</b>) after nasal administration of the indicated compounds, the habituation—dishabituation test was performed with the indicated odors. Naïve (untreated) mice were used as controls. For each group, the time spent in investigation (mean ± 1 SD; <i>n</i> = 10 mice) in each experimental group during each 3-min period (with 15-min intervals) is shown. **<i>P</i> < 0.01 (one-way ANOVA followed by the Dunnett test) compared with value for naïve mice or mice after nasal administration of CTB.</p

Immunohistochemical staining of the OE and OBs after nasal administration of 30 μg CT.

<p>OE and OBs were obtained at 0 (untreated), 24, or 72 h after nasal administration of 30 μg CT. (<b>A</b>) Frozen sections of OE were stained with an anti-CTA Ab or anti-CTB Ab (green) or an anti-OMP Ab (red). White arrows indicate the olfactory nerve layer. The number of OMP-positive cells (mean ± 1 SD; <i>n</i> = 3 mice) in each experimental group is shown at the right. (<b>B</b>) Frozen sections of OBs were stained with an anti-CTA Ab or anti-CTB Ab. (<b>C</b>) Frozen sections of OBs were stained with an anti-OMP Ab (converted to black and white images). Glomeruli at the dorsal and lateral surfaces of OBs (indicated by the boxes in panel B) are shown. The signal intensity (mean ± 1 SD; <i>n</i> = 3 mice) in each experimental group is shown at the right. Data are representative of three independent experiments. *<i>P</i> < 0.05, **<i>P</i> < 0.01 (Student’s <i>t</i>-test). Scale bars: (A, C) 20 μm, (B) 200 μm.</p