Research Progress in Molecular Biology of Fish Immunoglobulin M (IgM)

Immunoglobulin (Ig) is a type of globulin produced by B lymphocytes during pathogenic infection of vertebrates. It has immune functions and can realize specific recognition and neutralization of corresponding antigens. As IgM is reported first in fish, IgM is the first antibody produced during immune responses and plays a vital role in systemic and mucosal immune tissues. IgM molecules have two forms: membrane-bound IgM (mIgM) and secreted IgM (sIgM). The latter is produced by plasmacytes and secreted into body fluid, existing as immunological effect molecules. The former embeds into B cytomembrane and exists as an antigen receptor. It binds with assistant molecules to form cell receptor compounds. This study reviews research progress on the structures and production processes of IgM genes in different fish species and the distribution characteristics of IgM on B cells, mediated signal pathways, and functions. It aims to enrich basic theoretical knowledge of fish immunology and provide some scientific references for disease control in fishes

A single dose of DNA vaccine based on conserved H5N1 subtype proteins provides protection against lethal H5N1 challenge in mice pre-exposed to H1N1 influenza virus

<p>Abstract</p> <p>Background</p> <p>Highly pathogenic avian influenza virus subtype H5N1 infects humans with a high fatality rate and has pandemic potential. Vaccination is the preferred approach for prevention of H5N1 infection. Seasonal influenza virus infection has been reported to provide heterosubtypic immunity against influenza A virus infection to some extend. In this study, we used a mouse model pre-exposed to an H1N1 influenza virus and evaluated the protective ability provided by a single dose of DNA vaccines encoding conserved H5N1 proteins.</p> <p>Results</p> <p>SPF BALB/c mice were intranasally infected with A/PR8 (H1N1) virus beforehand. Six weeks later, the mice were immunized with plasmid DNA expressing H5N1 virus NP or M1, or with combination of the two plasmids. Both serum specific Ab titers and IFN-γ secretion by spleen cells in vitro were determined. Six weeks after the vaccination, the mice were challenged with a lethal dose of H5N1 influenza virus. The protective efficacy was judged by survival rate, body weight loss and residue virus titer in lungs after the challenge. The results showed that pre-exposure to H1N1 virus could offer mice partial protection against lethal H5N1 challenge and that single-dose injection with NP DNA or NP + M1 DNAs provided significantly improved protection against lethal H5N1 challenge in mice pre-exposed to H1N1 virus, as compared with those in unexposed mice.</p> <p>Conclusions</p> <p>Pre-existing immunity against seasonal influenza viruses is useful in offering protection against H5N1 infection. DNA vaccination may be a quick and effective strategy for persons innaive to influenza A virus during H5N1 pandemic.</p

An Escaping Outflow in a Galaxy with an Intermediate-mass Black Hole

While in massive galaxies active galactic nuclei (AGN) feedback plays an important role, the role of AGN feedback is still under debate in dwarf galaxies. With well spatially resolved data obtained from the Multi-Unit Spectroscopic Explorer (MUSE), we identify a spatially extended ($\rm \sim 3\; kpc$) and fast ($V_{80} \sim 471\; \rm km\;s^{-1}$) AGN-driven outflow in a dwarf galaxy: SDSS J022849.51-090153.8 with $M_{*} \sim 10^{9.6}\;{\rm M_{\odot}}$ that host an intermediate-mass black hole of $M_{\rm BH} \sim 10^5\;{\rm M_{\odot}}$ and $L_{\rm AGN}/L_{\rm Edd} \sim 0.15$. Through the measurement of the rotation curve, we estimate the escape velocity of the halo and the ratio of the outflow velocity to the halo escape velocity to be $1.09\pm0.04$, indicating that the outflow is capable of escaping not only the galaxy disk but the halo. The outflow size of our AGN is found to be larger than AGN in massive galaxies at the given AGN [O III] luminosity, while the size of the photo-ionized narrow-line region is comparable. These results suggest the important role of AGN feedback through outflows in dwarf galaxies when their central intermediate-mass black holes accrete at high-Eddington ratios.Comment: 12 pages, 2 tables, 12 figures, accepted for publication in MNRA

Research Progress on the Fish Complement C3 Gene

Complement (C) is a serum protein with immunity-related functions and enzymatic activities. It can induce inflammatory responses and antibody formation following activation by substances such as pathogens. Moreover, it is a crucial molecule in the congenital immune defense system. Complement manifests earlier than immunoglobulin in the evolutionary process of fish's immune system. Therefore, the complement system of fish is vital for congenital and acquired immunities. A complement system is a polymolecule system comprising more than 30 soluble proteins, membrane-bound proteins, and complement receptors. It can be activated through three pathways for immunoregulation, the clearance of the immune complex, etc. The liver primarily produces the fish complement C3, which is a significant component of the complement system of fishes. C3 is the hub of three activation pathways. Research works concerning the structure, generation process, expression, and functions of C3 in fishes are reviewed in this study

Acupuncture versus rehabilitation for post-stroke shoulder-hand syndrome: a systematic review and meta-analysis of randomized controlled trials

BackgroundShoulder-hand syndrome (SHS) is one of the common sequelae after stroke, which not only hinders the recovery of patients, but also increases the economic burden of the family. In the absence of effective treatment measures, acupuncture treatment has been widely used in China to treat post-stroke shoulder-hand syndrome, but the details are unclear. Therefore, this review aims to evaluate the true efficacy of acupuncture in patients with SHS.MethodsWe searched eight databases [PubMed, Embase, Web of Science, Cochrane library, China Biomedical Literature Database (CBM), China Science and Technology Journal (VIP) database, the China National Knowledge Infrastructure (CNKI) database, and Wan fang database] from its inception to March 2025, randomized controlled trials (RCTs) of SHS acupuncture treatment combined with rehabilitation (Rehab). Two investigators independently used pre-designed forms to extract valid data from eligible randomized controlled trials. Meta-analysis was implemented through the Rev. Man software (version 5.4). The strength of the evidence obtained was implemented using the GRADE profiler software. Adverse events (AEs) were collected by reading the full text and used to evaluate the safety of acupuncture treatment.ResultsForty-seven studies, involving 4,129 participants, met the eligibility criteria, and were included in the review. Overall meta-analysis showed that combined acupuncture rehabilitation significantly improved motor function (upper-limb Fugl-Meyer Assessment (FMA): 41 studies, mean difference (MD) 9.50, 95% confidence interval (CI) [8.47, 10.53]) and pain reduction (visual analog score (VAS): 37 studies, MD: −1.49, 95% CI [−1.66, −1.33]). It also improved activities of daily living (ADL) compared to rehabilitation alone (ADL: 17 studies, MD: 11.94, 95% CI [8.26, 13.63]). There was no significant difference in the occurrence of adverse events (AEs) between acupuncture treatment combined with Rehab and Rehab alone (p &gt; 0.05). The certainty of the evidence was rated low level because of flaws in the study design and considerable heterogeneity among the included studies.ConclusionThis review found that acupuncture treatment combined with Rehab treatment may have a positive promoting effect on improving motor function, reducing pain, and improving daily living ability in SHS patients. However, due to the existing methodological quality issues, our findings should be treated with caution. Future high-quality studies are urgently needed to validate our findings.Systematic review registrationhttps://www.crd.york.ac.uk/PROSPERO/view/CRD42024536169

Quantifying the escape of Lyα\alpha at z≈5−6z\approx 5-6: a census of Lyα\alpha escape fraction with Hα\alpha emitting galaxies spectroscopically confirmed by JWST and VLT/MUSE

JWST provides an unprecedented opportunity for unbiased surveys of H$\alpha$-emitting galaxies at $z>4$ with the NIRCam wide-field slitless spectroscopy (WFSS). In this work, we present a census of Ly$\alpha$ escape fraction ($f_{esc, Ly\alpha}$) of 165 star-forming galaxies at $z=4.9-6.3$ using their H$\alpha$ emission directly measured from FRESCO NIRCam/WFSS data. We search for Ly$\alpha$ emission of each H$\alpha$-emitting galaxy in VLT/MUSE data. The overall $f_{esc, Ly\alpha}$ measured by stacking is $f_{esc, Ly\alpha}$ is $0.090\pm0.006$. We find that $f_{esc, Ly\alpha}$ displays a strong dependence on the observed UV slope ($\beta_{\rm obs}$) and E(B-V), such that the bluest galaxies ($\beta_{\rm obs}\sim-2.5$) have the largest escape fractions ($f_{\rm esc, Ly\alpha}\approx0.6$), indicative of the crucial role of dust and gas in modulating the escape of Ly$\alpha$ photons. $f_{esc, Ly\alpha}$ is less well related to other parameters, including the UV luminosity and stellar mass, and the variation in $f_{esc, Ly\alpha}$ with them can be explained by their underlying coupling with E(B-V) or $\beta_{\rm obs}$. Our results suggest a tentative decline in $f_{esc, Ly\alpha}$ at $z\gtrsim 5$, implying increasing intergalactic medium attenuation towards higher redshift. Furthermore, the dependence of $f_{esc, Ly\alpha}$ on $\beta_{\rm obs}$ is proportional to that of the ionizing photon escape fraction ($f_{\rm esc, LyC}$), indicating the escape of Ly$\alpha$ and ionizing photon may be regulated by similar physical processes. With $f_{esc, Ly\alpha}$ as a proxy to $f_{\rm esc, LyC}$, we infer that UV-faint ($M_{\rm UV}>-16$) galaxies contribute $>70\%$ of the total ionizing emissivity at $z=5-6$. If these relations hold during the epoch of reionization, UV-faint galaxies can contribute the majority of UV photon budget to reionize the Universe.Comment: 17 pages, 12 figures; Accepted by the ApJ