γδ T cell antigen receptor polyspecificity enables T cell responses to a broad range of immune challenges.

γδ T cells are essential for immune defense and modulating physiological processes. While they have the potential to recognize large numbers of antigens through somatic gene rearrangement, the antigens which trigger most γδ T cell response remain unidentified, and the role of antigen recognition in γδ T cell function is contentious. Here, we show that some γδ T cell receptors (TCRs) exhibit polyspecificity, recognizing multiple ligands of diverse molecular nature. These ligands include haptens, metabolites, neurotransmitters, posttranslational modifications, as well as peptides and proteins of microbial and host origin. Polyspecific γδ T cells are enriched among activated cells in naive mice and the responding population in infection. They express diverse TCR sequences, have different functional potentials, and include the innate-like γδ T cells, such as the major IL-17 responders in various pathological/physiological conditions. We demonstrate that encountering their antigenic microbiome metabolite maintains their homeostasis and functional response, indicating that their ability to recognize multiple ligands is essential for their function. Human γδ T cells with similar polyspecificity also respond to various immune challenges. This study demonstrates that polyspecificity is a prevalent feature of γδ T cell antigen recognition, which enables rapid and robust T cell responses to a wide range of challenges, highlighting a unique function of γδ T cells.

The function of γδ T cells in humoral immune responses.

PURPOSE: The purpose of this review is to discuss the role of γδ T cells played in humoral immune responses. BACKGROUND: The γδ T cell receptor (γδ TCR) recognizes antigens, including haptens and proteins, in an MHC-independent manner. The recognition of these antigens by γδ TCRs crosses antigen recognition by the B cell receptors (BCRs), suggesting that γδ T cells may be involved in the process of antigen recognition and activation of B cells. However, the role of γδ T cells in humoral immune responses is still less clear. METHODS: The kinds of literature about the γδ T cell-B cell interaction were searched on PubMed with search terms, such as γδ T cells, antibody, B cell responses, antigen recognition, and infection. RESULTS: Accumulating evidence indicates that γδ T cells, independent of αß T cells, participate in multiple steps of humoral immunity, including B cell maturation, activation and differentiation, antibody production and class switching. Mechanically, γδ T cells affect B cell function by directly interacting with B cells, secreting cytokines, or modulating αß T cells. CONCLUSION: In this review, we summarize current knowledge on how γδ T cells take part in the humoral immune response, which may assist future vaccine design.

catena-Poly[[(2,9-dimethyl-1,10-phenanthroline-κN,N')cobalt(II)]-µ-malonato-κO,O:O,O].

In the title compound, [Co(C(3)H(2)O(4))(C(14)H(12)N(2))](n), the Co(II) ion is in a distorted octa-hedral coordination being chelated by a 2,9-dimethyl-1,10-phenanthroline mol-ecule (dmphen) and two carboxyl-ate groups of two malonate ligands The malonate ligand acts in a bridging mode, forming coordination chains along [100]. π-π stacking inter-actions between dmphen ligands [inter-planar distances = 3.414 (4) and 3.447 (4) Å] organize the coordination polymers into supra-molecular double chains.

catena-Poly[4,4'-bipyridinium [[diaqua-disulfatocadmium(II)]-µ-4,4'-bipyridine-κN:N'] dihydrate].

The title compound, {(C(10)H(10)N(2))[Cd(SO(4))(2)(C(10)H(8)N(2))(H(2)O)(2)]·2H(2)O}(n), consists of anionic chains of the Cd complex, diprotonated 4,4'-bipyridinium cations and uncoordinated water mol-ecules. In the anionic chain, the Cd atom lies on a center of inversion in an octa-hedral geometry. The midpoint of the coordinated bipyridine also resides on a center of inversion, as does the non-coordinated bipyridinium counterion. O-H⋯O and N-H⋯O hydrogen bonding inter-actions and π-π stacking inter-actions in the structure are responsible for the supra-molecular assembly.

A Preliminary Study of the Effects of Venous Drainage Position on Arterial Blood Supply and Venous Return within the Conjoined Flap.

BACKGROUND: Conjoined flap viability is associated with arterial blood supply and venous return. This study aimed to assess the effects of venous drainage position on arterial blood supply and venous return within the conjoined flap. METHODS: Fifty-four rats were divided randomly into three groups (n = 18 per group). In experimental group 2, only the right intercostal posterior artery and the left iliolumbar vein were maintained; meanwhile, only the right intercostal posterior artery and the left intercostal posterior vein were preserved in experimental group 1. The control group had only the right intercostal posterior artery and vein preserved. The distances between angiosomes were measured. At 7 days after surgery, flap survival was evaluated, lead oxide-gelatin flap angiography was performed, and average microvessel density was assessed by hematoxylin and eosin staining, and lactate levels were assessed. RESULTS: The distance between angiosomes I and II was the shortest, whereas angiosomes I and III were most distant (p < 0.05). At 7 days after surgery, survival rates in experimental group 2 and experimental group 1 were both 100 percent, whereas 86.5 ± 1.6 percent of controls survived. Furthermore, angiogenesis was more obvious in experimental group 2 than in experimental group 1 and controls. Moreover, lactate levels were lower in experimental group 2 (7.47 ± 0.17 mM) and experimental group 1 (8.03 ± 0.31 mM) compared with control values (9.98 ± 0.37 mM; p < 0.05). CONCLUSION: Changes in position of venous drainage might cause continuous arterial high-pressure perfusion and venous superdrainage, which improves flap survival.