An mRNA vaccine encoding the SARS-CoV-2 receptor-binding domain protects mice from various Omicron variants.

Here, we assessed the efficacy of a lipid nanoparticle-based mRNA vaccine candidate encoding the receptor-binding domain (LNP-mRNA-RBD) in mice. Mice immunized with LNP-mRNA-RBD based on the ancestral strain (ancestral-type LNP-mRNA-RBD) showed similar cellular responses against the ancestral strain and BA.5, but their neutralizing activity against BA.5 was lower than that against the ancestral strain. The ancestral-type LNP-mRNA-RBD protected mice from the ancestral strain or BA.5 challenge; however, its ability to reduce the viral burdens after BA.5 challenge was limited. In contrast, immunization with bivalent LNP-mRNA-RBD consisting of the ancestral-type and BA.4/5-type LNP-mRNA-RBD or monovalent BA.4/5-type LNP-mRNA-RBD elicited robust cellular responses, as well as high and moderate neutralizing titers against BA.5 and XBB.1.5, respectively. Furthermore, the vaccines containing BA.4/5-type LNP-mRNA-RBD remarkably reduced the viral burdens following BA.5 or XBB.1.5 challenge. Overall, our findings suggest that LNP-mRNA-RBD is effective against SARS-CoV-2 infection.

Droplet duos on water display pairing, autonomous motion, and periodic eruption.

Under non-equilibrium conditions, liquid droplets dynamically couple with their milieu through the continuous flux of matter and energy, forming active systems capable of self-organizing functions reminiscent of those of living organisms. Among the various dynamic behaviors demonstrated by cells, the pairing of heterogeneous cell units is necessary to enable collective activity and cell fusion (to reprogram somatic cells). Furthermore, the cyclic occurrence of eruptive events such as necroptosis or explosive cell lysis is necessary to maintain cell functions. However, unlike the self-propulsion behavior of cells, cyclic cellular behavior involving pairing and eruption has not been successfully modeled using artificial systems. Here, we show that a simple droplet system based on quasi-immiscible hydrophobic oils (perfluorodecalin and decane) deposited on water, mimics such complex cellular dynamics. Perfluorodecalin and decane droplet duos form autonomously moving Janus or coaxial structures, depending on their volumes. Notably, the system with a coaxial structure demonstrates cyclic behavior, alternating between autonomous motion and eruption. Despite their complexity, the dynamic behaviors of the system are consistently explained in terms of the spreading properties of perfluorodecalin/decane duplex interfacial films.

IgE sensitivity to Malassezia pachydermatis and mite allergens in dogs with atopic dermatitis.

In this study, dogs with atopic dermatitis were separated into non-food-induced atopic dermatitis (NFIAD) group (n = 15) and food-induced atopic dermatitis (FIAD) group (n = 37) based on an elimination diet test. IgE reactivity for crude Malassezia pachydermatis (M. pachydermatis) and house dust mites (HDM) allergen extracts was investigated in the two groups using fluorometric enzyme-linked immunosorbent assay (ELISA) and intradermal skin test (IDST). Nine (60%) of the 15 dogs in NFIAD group and 6 (16%) of the 37 dogs in FIAD group showed specific IgE for M. pachydermatis (Mann-Whitney U-test, P < 0.01). By immunoblotting analysis, the pooled serum samples from dogs with IgE for M. pachydermatis showed IgE reactivity for 50 kDa protein of M. pachydermatis. Twelve (80%) of the 15 dogs in NFIAD group and 8 (22%) of the 37 dogs in FIAD group showed specific IgE for HDM (Mann-Whitney U-test, P < 0.01). In addition, the dogs in NFIAD group significantly show a positive IDST to M. pachydermatis and HDM extracts compared with the dogs in FIAD group. The results suggest that dogs with NFIAD are at increased risk of becoming sensitized to the normal commensal organism M. pachydermatis compared with dogs with FIAD, perhaps co-sensitization occurred due to an HDM protease antigen's, Der f 1 and/or Der p 1, proteolytic activity related epidermal skin barrier defects. Treatment to limit skin colonization may thus be especially important in NFIAD.

Age-Specific Profiles of Antibody Responses against Respiratory Syncytial Virus Infection.

Respiratory syncytial virus (RSV) is one of the most prevalent causative agents of lower respiratory tract infections worldwide, especially in infants around 3 to 4months old. Infants at such a young age have maternally-transferred passive antibodies against RSV but do not have active immune systems efficient enough for the control of RSV infection. In order to elucidate age-specific profiles of immune responses against RSV protection, antibody responses were examined by using blood samples in both acute and convalescent phases obtained from child patients and adult patients. In addition to the serum neutralization activity, antibody responses to the RSV fusion protein (F protein) were dissected by analyzing levels of total IgG, IgG subclasses, the binding stability, and the levels of antibody for the neutralization epitopes. It was suggested that children's antibody responses against RSV are matured over months and years in at least 5 stages based on 1) levels of the neutralization titer and IgG3 for F protein in the convalescent phase, 2) geometric mean ratios of the neutralization titers and levels of IgG1 and IgG2 for F protein in the convalescent phase compared to those levels in the acute phase, 3) the affinity maturation of IgG for F protein and the cross reactivity of IgG for RSV glycoproteins of groups A and B, 4) levels of neutralization epitope-specific IgG, and 5) augmentation of overall antibody responses due to repetitive RSV infection.

Altered gene expression of glycosyltransferases and sialyltransferases and total amount of glycosphingolipids following herpes simplex virus infection.

There is a case report of a patient with overlapping Guillain-Barré syndrome and Bickerstaff brainstem encephalitis after infection with herpes simplex virus type 1 (HSV-1), who carried high titers of serum anti-GQ1b IgG antibodies. Several studies have linked viral infection to the modulation of ganglioside expression such as human T-lymphotropic virus to GD2 and simian virus 40 to GM3. Also, enhancement of the expression of GM2 on the cell membrane after cytomegalovirus infection has been reported. The objective of this study was to unveil the relationship between HSV-1 infection and the alteration of cellular ganglioside expression in neuronal and glial cell lines. In addition to these cell lines, several human tumor cell lines including astrocytoma cells, neuroblastoma cells, T-cell leukemia cells and kidney cells derived from normal human and monkey were infected with HSV-1 as well as HSV-2. To measure changes in ganglioside-related gene expressions and gangliosides levels in cells, quantitative PCR and glycosphingolipid-glycomic analysis were performed. Changes in gene expression of glycosyltransferases and sialyltransferases were observed in HSV-1- and HSV-2-infected cells, although with different trends. 39 glycosphingolipid-glycans were quantitatively analyzed. HSV-1 and HSV-2 infections resulted in changes in the total amount of gangliosides depending on the cell lines used and type of virus. Qualitative changes caused by each infection of HSV-1 and HSV-2 were almost negligible.

Polyclonal IgM and IgA block in vitro complement deposition mediated by anti-ganglioside antibodies in autoimmune neuropathies.

Intravenous immunoglobulin (IVIG), consisting of IgG, is the first-line treatment for Guillain-Barré syndrome and multifocal motor neuropathy. IgG, but neither IgM nor IgA, has been demonstrated in vitro to inhibit complement deposition mediated by anti-ganglioside autoantibodies in sera from patients with both conditions. The objective of this study is to investigate the in vitro effectiveness of IgM and IgA in inhibiting complement deposition to ganglioside/anti-ganglioside antibody complexes. Serum samples were obtained from patients with multifocal motor neuropathy associated with anti-GM1 IgM antibodies, Guillain-Barré syndrome associated with anti-GM1 IgG antibodies and Miller Fisher syndrome associated with anti-GQ1b IgG antibodies. Inhibition of complement deposition using different immunoglobulin preparations was measured by enzyme-linked immunosorbent assay. IgM/A-enriched IVIG and immunoglobulin isotypes (polyclonal IgM and IgA) showed higher potential in inhibiting complement deposition than standard IVIG. Although the safety concerns about the use of IgM and IgA for an immunotherapy still remain, IgM and IgA may serve as an alternative immunotherapy in those anti-ganglioside antibody-mediated neuropathies.

IgE reactivity to hen egg white allergens in dogs with cutaneous adverse food reactions.

Dogs with cutaneous adverse food reactions (CAFR) often have specific IgE to food allergens. Egg white, which is majorly composed of ovomucoid, ovalbumin, ovotransferrin, and lysozyme, is a food allergen in dogs. Information of the IgE reactivity to purified egg white allergens supports accurate diagnosis and efficiency treatment in humans. However, to the best of our knowledge, there have been no studies on the IgE reactivity to purified egg white allergens in dogs. Here, we investigated the IgE reactivity to crude and purified allergens of hen egg white in dogs with CAFR. First, when we examined serum samples from 82 dogs with CAFR for specific IgE to crude egg white by ELISA, 9.8% (8/82) of the dogs with CAFR showed the IgE reactivity to crude egg white. We then used sera from the eight dogs with positive IgE reactivity to crude egg white to examine the IgE reactivity to four purified allergens, ovomucoid, ovalbumin, ovotransferrin, and lysozyme, by ELISA. We found that 75% (6/8) of the dogs showed IgE reactivity to both ovomucoid and ovalbumin, and that 37.5% (3/8) of the dogs showed IgE reactivity to ovotransferrin. None (0/8) showed IgE reactivity to lysozyme. Moreover, validating these results, the immunoblot analyses were performed using the sera of the three dogs showing the highest IgE reactivity to crude egg white. Both anti-ovomucoid and anti-ovalbumin IgE were detected in the sera of these dogs, while anti-ovotransferrin IgE was not detected. Considering these, ovomucoid and ovalbumin appears to be the major egg white allergens in dogs with CAFR.

Prevalence of food-responsive enteropathy among dogs with chronic enteropathy in Japan.

There have been limited reports on the prevalence of adverse food reactions among dogs suffering from chronic enteropathy (CE) in Japan. We examined the prevalence and histological features of food-responsive enteropathy (FRE) in a total of 32 dogs with history of CE. Fourteen of 18 cases (56.2%) diagnosed as FRE had lymphocytic-plasmacytic enteritis or eosinophilic enteritis by histopathological examination. Characteristic histopathological changes indicating FRE were not identified in 18 cases, though 4 cases did not show any abnormalities. Results collected from this study provided important information that can help to change the way dogs with CE are treated in the future.

Cross-reactivity between major IgE core epitopes on Cry j 2 allergen of Japanese cedar pollen and relevant sequences on Cha o 2 allergen of Japanese cypress pollen.

BACKGROUND: Cry j 2 and Cha o 2 are major allergens in Japanese cedar (Cryptomeria japonica; CJ) and Japanese cypress (Chamaecyparis obtusa; CO) pollen, respectively. Here, we assessed the epitopes related to the cross-reactivity between Cry j 2 and Cha o 2 using in vitro analyses. METHODS: Peptides were synthesized based on Cry j 2 sequential epitopes and relevant Cha o 2 amino acid sequences. Four representative monoclonal antibodies (mAbs) against Cry j 2 were used according to their epitope recognitions. Serum samples were collected from 31 patients with CJ pollinosis. To investigate cross-reactivity between Cry j 2 and Cha o 2, ELISA and inhibition ELISA were performed with mAbs and sera from patients with CJ pollinosis. RESULTS: Two of four mAbs had reactivity to both Cry j 2 and Cha o 2. Of these two mAbs, one mAb (T27) recognized the amino acid sequence (169)KVVNGRTV(176) on Cha o 2. This is related to the core epitope (169)KWVNGREI(176) on Cry j 2, which is an important IgE epitope. In addition, we found that these correlative sequences and purified allergens showed cross-reactivity between Cry j 2 and Cha o 2 in IgE of CJ patients. CONCLUSIONS: We demonstrated the importance of (169)KVVNGRTV(176) in Cha o 2 for cross-reactivity with the Cry j 2 epitope (169)KWVNGREI(176), which plays an important role in allergenicity in CJ pollinosis. Our results are useful for the development of safer and more efficient therapeutic strategies for the treatment of CJ and CO pollen allergies.

Autoantibodies to tetraspanins (CD9, CD81 and CD82) in demyelinating diseases.

Tetraspanin family proteins, CD9, CD81 and CD82 are expressed in the oligodendrocytes and Schwann cells. We investigated autoantibodies to tetraspanin proteins in patients with demyelinating diseases. Sera were collected from 119 multiple sclerosis patients, 19 neuromyelitis optica, 42 acute inflammatory demyelinating polyneuropathy, 23 chronic inflammatory demyelinating polyneuropathy and 13 acute motor axonal neuropathy as well as 55 healthy controls. Few multiple sclerosis and acute inflammatory demyelinating polyneuropathy patients had autoantibodies that were weakly reactive to CD9 or CD81 but the significance is unclear. It is unlikely that these autoantibodies are pathogenic or serve as potential biomarkers in demyelinating diseases.

Experimental Verification of the Effects on Normal Domestic Cats by Feeding Prescription Diet for Decreasing Stress.

The objective of this study was to evaluate the effects of diet on the feline stress response by measuring plasma and urinary cortisol. A study diet was developed with a unique combination of nutrients that supports the management of stressful situations. The specific formulation of the diet included alpha-casozepine, which is believed to have an anxiolytic effect, and tryptophan supplementation. Tryptophan is the precursor for the synthesis of the neurotransmitter serotonin. Twenty-one indoor cats were fed with the study diet (n = 10) or a control diet (n = 11) for 8 weeks, after which physiological responses were evaluated. The study diet significantly increased the ratio of plasma tryptophan to large neutral amino acids and decreased urinary cortisol concentrations after being consumed daily for 8 weeks, but there was no effect on plasma cortisol levels following a stressful event (veterinary examination and blood draw). Further studies, such as behavioral analyses, are needed to clarify the effects of the study diet.

Are ERM (ezrin/radixin/moesin) proteins targets for autoantibodies in demyelinating neuropathies?

Ezrin, radixin and moesin, which are strongly expressed in the Schwann cell microvilli, are putative targets for autoantibodies in acute or chronic inflammatory demyelinating polyneuropathy (AIDP or CIDP). An association between anti-moesin IgG antibodies and cytomegalovirus-related AIDP has been postulated. None of 41 AIDP patients, including 8 cytomegalovirus-related AIDP patients, and 23 CIDP had IgG or IgM antibodies to ezrin, radixin and moesin; whereas, one patient with cytomegalovirus-related AIDP had anti-ezrin IgM antibodies. Ezrin, radixin and moesin are unlikely targets for autoantibodies in AIDP and CIDP, and the association of anti-moesin antibodies with cytomegalovirus-related AIDP was not confirmed.

Complement regulatory proteins (CD46, 55 and 59) expressed on Schwann cells: immune targets in demyelinating neuropathies?

Given their localization and important role in regulating complement, complement regulatory proteins may act as target antigens and their antibodies as biomarkers in demyelinating neuropathies. We investigated the binding of autoantibodies to complement regulatory proteins (CD46, 55 and 59) in demyelinating diseases. In 42 acute inflammatory demyelinating polyneuropathy, 23 chronic inflammatory demyelinating polyneuropathy, 13 acute motor axonal neuropathy, 71 multiple sclerosis, and 19 neuromyelitis optica patients as well as 55 healthy controls, we were unable to detect significant titers of antibodies to CD46, CD55 and CD59. These autoantibodies are unlikely to be biomarkers in acute and chronic inflammatory demyelinating polyneuropathies.

Autoantibodies to GM1 and GQ1bα are not biological markers of Alzheimer's disease.

A few studies have reported the association of autoantibodies to GM1 or GQ1bα with Alzheimer's disease (AD) or vascular dementia. Here we investigated whether patients with AD or vascular dementia had high titers of the anti-ganglioside antibodies. Sera were obtained from patients with AD (n = 22), vascular dementia (n = 14), Guillain-Barré syndrome, and multifocal motor neuropathy as well as normal controls. Enzyme-linked immunosorbent assay showed titers of IgG and IgM anti-GM1, anti-GQ1bα, and anti-GT1aα antibodies did not differ among AD, vascular dementia, and normal controls, and being remarkably lower than those in Guillain-Barré syndrome and multifocal motor neuropathy. The anti-ganglioside antibodies are not biological markers of AD.

Analysis of conformational and sequential IgE epitopes on the major allergen Cry j 2 of Japanese cedar (Cryptomeria japonica) pollen in humans by using monoclonal antibodies for Cry j 2.

PURPOSE: Japanese cedar (Cryptomeria japonica; CJ) pollinosis is a type I allergy induced by CJ pollen, and Cry j 2 is one of the major allergens in this pollen. In a previous study, we analyzed IgE epitopes on Cry j 2 in humans by using synthetic peptides. The main purpose of this study was to identify B-cell epitopes on Cry j 2 in patients with CJ pollinosis by using monoclonal antibodies (mAbs) for Cry j 2. METHODS: We used ELISA with mAbs for the epitope analysis. Sera samples were collected from 80 patients with CJ pollinosis, and allergenic epitopes for mAbs and human IgE were identified using ELISA with synthetic peptides. The importance of the epitopes for human IgE was analyzed using an inhibition ELISA. RESULTS: Four independent epitopes (epitope #1, #2, #3, and #4) were identified on Cry j 2 with the use of mAbs. Epitope #3 and #4, corresponding to peptides No. 25 and No. 33, respectively, were newly determined as epitopes for mAbs and human IgE. Inhibition ELISA showed that not only epitope #2 (sequential) but epitope #1 (conformational) may play an important role in the CJ pollinosis. CONCLUSIONS: Our results revealed 4 epitopes, including two new ones, on Cry j 2. We also found that inhibition ELISA with appropriate mAbs could be a viable method of evaluating the importance of the conformational and sequential epitopes for human IgE. These results are beneficial for the development of safer and more efficient therapeutic strategies for treating CJ pollinosis.

IgE reactivity to a Cry j 3, an allergen of Japanese cedar (Cryptomeria japonica) pollen in dogs with canine atopic dermatitis.

The present study investigated IgE reactivity to a new Cryptomeria japonica pollen allergen (Cry j 3) in dogs with atopic dermatitis by using a fluorometric ELISA. Serum samples from 15 dogs that showed IgE sensitivity to crude C. japonica pollen allergen by ELISA were tested for specific IgE to each allergen, individually. All 15 dogs had anti-Cry j 1 IgE, 6 (40%) had anti-Cry j 2 IgE, and 11 (73%) had anti-Cry j 3 IgE. Further, we found that these anti-Cry j 3 IgE reacted to Cry j 3 with immunoblotting analysis. These findings indicate that Cry j 3 may be a major allergen in dogs.

The seasonal fluctuation of plasma amino acids in aquarium-maintained bottlenose dolphins (Tursiops truncatus).

Although there has been extensive research on plasma amino acid profiles of mammals, there is currently a lack of information on seasonal differences in the concentrations of plasma amino acids specifically in cetaceans. The present study examined the response of the plasma amino acids to seasonal changes in the culture environment after controlling for the effect of sex and age. Significant seasonal changes in plasma carnosine (P=0.012), cystine (P=0.0014), isoleucine (P=0.0042), methionine (P=0.002), ornithine (P=0.0096), and taurine (P=0.032) were observed. These amino acids were mainly related to capacity for exercise, ammonia detoxification, thermoregulation, and osmoregulation. We proposed that optimizing plasma amino acids levels by supplementation of amino acids should be of considerable benefit for aquarium-maintained bottlenose dolphins. This study constitutes a first step towards improving our understanding of the metabolism of aquarium-maintained bottlenose dolphins. We also revealed that the ratio of tryptophan to large neutral amino acids significantly declined (P=0.0076), suggesting reduction in serotonin synthesis in winter and autumn. Although further studies are needed, this finding implied that bottlenose dolphins could produce behavioral changes seasonally by the alteration of serotonin activity. To better understand the metabolic machinery for amino acids that facilitate the adaptation of marine mammals to their environments, it is essential to continue monitoring of and further investigations into relationships between plasma amino acids and specific environmental factors.

Large-scale survey of adverse reactions to canine non-rabies combined vaccines in Japan.

Canine non-rabies combined vaccines are widely used to protect animals from infectious agents, and also play an important role in public health. We performed a large-scale survey to investigate vaccine-associated adverse events (VAAEs), including anaphylaxis, in Japan by distributing questionnaires on VAAEs to veterinary hospitals from April 1, 2006 through May 31, 2007. Valid responses were obtained for 57,300 vaccinated dogs at 573 animal hospitals; we obtained VAAEs information for last 100 vaccinated dogs in each veterinary hospital. We found that of the 57,300, 359 dogs showed VAAEs. Of the 359 dogs, death was observed in 1, anaphylaxis in 41, dermatological signs in 244, gastrointestinal signs in 160, and other signs in 106. Onset of VAAEs was mostly observed within 12h after vaccination (n=299, 83.3%). In this study, anaphylaxis events occurred within 60 min after vaccination, and about half of these events occurred within 5 min (n=19, 46.3%). Furthermore, where anaphylaxis was reported, additional information to support the diagnosis was obtained by reinvestigation. Our resurvey of dogs with anaphylaxis yielded responses on 31 dogs; 27 of these demonstrated collapse (87.1%), 24 demonstrated cyanosis (77.4%), and both signs occurred in 22 (71.0%). Higher rates of animal VAAEs, anaphylaxis, and death were found in Japan than in other countries. Further investigations, including survey studies, will be necessary to elucidate the interaction between death and vaccination and the risk factors for VAAEs, and thus develop safer vaccines. Moreover, it may also be necessary to continually update the data of VAAEs.