scholarly journals Physiological condition reflects polymorphism at the toll-like receptors in a colonial waterbird

The Auk ◽  
2021 ◽  
Author(s):  
Patrycja Podlaszczuk ◽  
Piotr Indykiewicz ◽  
Maciej Kamiński ◽  
Piotr Minias

Abstract Toll-like receptors (TLRs) are a crucial component of vertebrate innate immune response. Despite their importance, associations of TLR diversity with fitness-related traits have rarely been examined in wild animal populations. Here, we tested for associations of TLR polymorphism with physiological condition in a colonial waterbird, the Black-headed Gull (Chroicocephalus ridibundus). Physiological condition and polymorphism at 4 TLR loci were assessed in 60 gulls from a breeding colony in northern Poland. We found that blood hemoglobin and plasma albumin concentrations were positively associated with TLR diversity across all genotyped loci. Plasma concentrations of albumin and triglycerides were also associated with the presence of specific TLR variants and locus-specific diversity. All significant associations between physiological condition and TLRs were primarily apparent at the level of nucleotide, rather than amino acid allelic variants. Although the exact molecular mechanisms responsible for these associations require further investigation, our study provides strong correlational support for links between TLR diversity and physiological condition in a wild avian population, and it adds to the growing, but still modest, body of evidence for the fitness-related consequences of individual TLR repertoire in wild birds.

Proceedings ◽  
2019 ◽  
Vol 22 (1) ◽  
pp. 72
Author(s):  
Lena Trifonov ◽  
Vadim Nudelman ◽  
Michael Zhenin ◽  
Guy Cohen ◽  
Krzysztof Jozwiak ◽  
...  

TLR4, a member of the toll-like receptors (TLRs) family, serves as a pattern recognition receptor in the innate immune response to different microbial pathogens. [...]


2020 ◽  
Vol 21 (24) ◽  
pp. 9769
Author(s):  
Saaya Koike ◽  
Kenshi Yamasaki

The epidermis is located in the outermost layer of the living body and is the place where external stimuli such as ultraviolet rays and microorganisms first come into contact. Melanocytes and melanin play a wide range of roles such as adsorption of metals, thermoregulation, and protection from foreign enemies by camouflage. Pigmentary disorders are observed in diseases associated with immunodeficiency such as Griscelli syndrome, indicating molecular sharing between immune systems and the machineries of pigment formation. Melanocytes express functional toll-like receptors (TLRs), and innate immune stimulation via TLRs affects melanin synthesis and melanosome transport to modulate skin pigmentation. TLR2 enhances melanogenetic gene expression to augment melanogenesis. In contrast, TLR3 increases melanosome transport to transfer to keratinocytes through Rab27A, the responsible molecule of Griscelli syndrome. TLR4 and TLR9 enhance tyrosinase expression and melanogenesis through p38 MAPK (mitogen-activated protein kinase) and NFκB signaling pathway, respectively. TLR7 suppresses microphthalmia-associated transcription factor (MITF), and MITF reduction leads to melanocyte apoptosis. Accumulating knowledge of the TLRs function of melanocytes has enlightened the link between melanogenesis and innate immune system.


2021 ◽  
Vol 4 (1) ◽  
Author(s):  
Cheng-Kang Tang ◽  
Chih-Hsuan Tsai ◽  
Carol-P. Wu ◽  
Yu-Hsien Lin ◽  
Sung-Chan Wei ◽  
...  

AbstractTo avoid inducing immune and physiological responses in insect hosts, parasitoid wasps have developed several mechanisms to inhibit them during parasitism, including the production of venom, specialized wasp cells, and symbioses with polydnaviruses (PDVs). These mechanisms alter the host physiology to give the wasp offspring a greater chance of survival. However, the molecular mechanisms for most of these alterations remain unclear. In the present study, we applied next-generation sequencing analysis and identified several miRNAs that were encoded in the genome of Snellenius manilae bracovirus (SmBV), and expressed in the host larvae, Spodoptera litura, during parasitism. Among these miRNAs, SmBV-miR-199b-5p and SmBV-miR-2989 were found to target domeless and toll-7 in the host, which are involved in the host innate immune responses. Microinjecting the inhibitors of these two miRNAs into parasitized S. litura larvae not only severely decreased the pupation rate of Snellenius manilae, but also restored the phagocytosis and encapsulation activity of the hemocytes. The results demonstrate that these two SmBV-encoded miRNAs play an important role in suppressing the immune responses of parasitized hosts. Overall, our study uncovers the functions of two SmBV-encoded miRNAs in regulating the host innate immune responses upon wasp parasitism.


2013 ◽  
Vol 16 (1) ◽  
pp. 17-23 ◽  
Author(s):  
I. Mikulikova ◽  
H. Modra ◽  
J. Blahova ◽  
K. Kruzikova´ ◽  
P. Marsalek ◽  
...  

Abstract Effects of a high terbuthylazine concentration (3.3 mg/l) on Cyprinus carpio were studied using a commercial herbicide formulation Click 500 SC (terbuthylazine 500 g/l). The fish were exposed to the pesticide for 24 h and allowed to recover for 6 days. Biometric parameters, plasma biochemical parameters and biomarkers of oxidative stress as well as histopathological changes in selected tissues were assessed on day 1 and 7. After a 24-h exposure, there were significant alterations found in the activities of alanine aminotransferase (ALT) and aspartate aminotransferase (AST) as well as in the plasma concentrations of glucose, natrium, chlorides, calcium and phosphorus. Hepatosomatic index, plasma albumin and lactate reflected the treatment with a delay. Ion levels and ALT were found to be restored after a 6-day recovery period, which was too short for AST activity and glucose to diminish to the control levels. The histopathological examination revealed disorders in the gills of the exposed fish, however, the changes were not detected after a 6-day recovery period. The study shows high regeneration potential of the fish.


2021 ◽  
Vol 12 ◽  
Author(s):  
Jiexia Wen ◽  
Bin Xuan ◽  
Yang Liu ◽  
Liwei Wang ◽  
Li He ◽  
...  

Inflammasomes comprise a family of cytosolic multi-protein complexes that modulate the activation of cysteine-aspartate-specific protease 1 (caspase-1) and promote the maturation and secretion of interleukin (IL)-1β and IL-18, leading to an inflammatory response. Different types of inflammasomes are defined by their sensor protein which recognizes pathogenic ligands and then directs inflammasome assembly. Although the specific molecular mechanisms underlying the activation of most inflammasomes are still unclear, NLRC4 inflammasomes have emerged as multifaceted agents of the innate immune response, playing important roles in immune defense against a variety of pathogens. Other studies have also expanded the scope of NLRC4 inflammasomes to include a range of inherited human autoimmune diseases as well as proposed roles in cancer. In this review article, we provide an updated overview of NLRC4 inflammasomes, describing their composition, activation mechanisms and roles in both microbial infections and other disease conditions.


2021 ◽  
Author(s):  
Leetah Senkpeil ◽  
Jyoti Bhardwaj ◽  
Morgan Little ◽  
Prasida Holla ◽  
Aditi Upadhye ◽  
...  

Baseline innate immune signatures can influence protective immunity following vaccination. Here, we used systems transcriptional analysis to assess the molecular mechanisms underlying differential immunogenicity and protective efficacy results of a clinical trial of the radiation-attenuated whole sporozoite PfSPZ Vaccine in African infants. Innate immune activation and myeloid signatures at pre-vaccination baseline correlated with protection from Plasmodium falciparum infection in placebo controls, while the same signatures predicted susceptibility to infection among infants who received the highest and most protective dose of the PfSPZ Vaccine. Machine learning identified monocytes and an antigen presentation signature as pre-vaccination features predictive of malaria infection after highest-dose PfSPZ vaccination. Consistent with these human data, innate stimulation in vivo conferred protection against malaria infection in mice while diminishing the CD8+ T cell response to radiation-attenuated sporozoites. These data establish a dichotomous role of innate stimulation for malaria protection and induction of protective immunity of whole-sporozoite malaria vaccines.


2021 ◽  
pp. 1-20
Author(s):  
Gyöngyi Cinege ◽  
Lilla B. Magyar ◽  
Attila L. Kovács ◽  
Zita Lerner ◽  
Gábor Juhász ◽  
...  

Multinucleated giant hemocytes (MGHs) represent a novel type of blood cell in insects that participate in a highly efficient immune response against parasitoid wasps involving isolation and killing of the parasite. Previously, we showed that circulating MGHs have high motility and the interaction with the parasitoid rapidly triggers encapsulation. However, structural and molecular mechanisms behind these processes remained elusive. Here, we used detailed ultrastructural analysis and live cell imaging of MGHs to study encapsulation in <i>Drosophila ananassae</i> after parasitoid wasp infection. We found dynamic structural changes, mainly driven by the formation of diverse vesicular systems and newly developed complex intracytoplasmic membrane structures, and abundant generation of giant cell exosomes in MGHs. In addition, we used RNA sequencing to study the transcriptomic profile of MGHs and activated plasmatocytes 72 h after infection, as well as the uninduced blood cells. This revealed that differentiation of MGHs was accompanied by broad changes in gene expression. Consistent with the observed structural changes, transcripts related to vesicular function, cytoskeletal organization, and adhesion were enriched in MGHs. In addition, several orphan genes encoding for hemolysin-like proteins, pore-forming toxins of prokaryotic origin, were expressed at high level, which may be important for parasitoid elimination. Our results reveal coordinated molecular and structural changes in the course of MGH differentiation and parasitoid encapsulation, providing a mechanistic model for a powerful innate immune response.


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