Phylogenomic analyses reveal a single deep-water colonisation in Patellogastropoda.

Patellogastropoda, the true limpets, is a major group of gastropods widely distributed in marine habitats from the intertidal to deep sea. Though important for understanding their evolutionary radiation, the phylogenetic relationships among the patellogastropod families have always been challenging to reconstruct, with contradictory results likely due to insufficient sampling. Here, we obtained mitogenomic and phylogenomic data (transcriptomic or genomic) from six species representing the three predominantly deep-water patellogastropod families: Lepetidae, Neolepetopsidae, and Pectinodontidae. By using various phylogenetic methods, we show that mitogenome phylogeny recovers monophyly of eight families in most of the trees, though the relationships among families remain contentious. Meanwhile, a more robust family-level topology consistent with morphology was achieved by phylogenomics. This also reveals that these mainly deep-water families are monophyletic, suggesting a single colonisation of the deep water around the Jurassic. We also found a lack of significant correlation between genome size and habitat depth, despite some deep-water species exhibiting larger genome sizes. Our phylogenomic tree provides a stable phylogenetic backbone for Patellogastropoda that includes seven of the nine recognized families and paves the way for future evolutionary analyses in this major group of molluscs.

A New Paralepetopsis Limpet from a South China Sea Seep Hints at a Paraphyletic Neolepetopsidae.

Neolepetopsidae is a little-studied true limpet family only known from deep-sea chemosynthetic ecosystems, containing just over a dozen species in three genera: Neolepetopsis, Paralepetopsis, and Eulepetopsis. Although considered monophyletic by a recent phylogenetic analysis, a lack of Paralepetopsis sequence linked to morphology casts some uncertainty. Here, we discovered a new species of Paralepetopsis from the Haima methane seep in the South China Sea, described as Paralepetopsis polita sp. nov. The new species is distinct from all other described Paralepetopsis by its smooth and semi-transparent shell, combined with a radula exhibiting pluricuspid teeth with two cusps. We tested its relationship with other neolepetopsids using a molecular phylogeny reconstructed from the mitochondrial COI gene, revealing a surprising position nested within Lepetidae, a family with a very different radula morphology. The clade containing lepetids and our new species was recovered sister to other neolepetopsids with sequence data available. This hints at a paraphyletic Neolepetopsidae, and suggests the neolepetopsid-type radula might not be exclusive to one monophyletic group of limpets.

The differential diagnostic value of dual-phase 18F-DCFPyL PET/CT in prostate carcinoma.

OBJECTIVE: Binding of 18F-DCFPyL at prostate cancer (PC) cells increases over time. The dual-phase protocol may be helpful in separating benign lesions from malignant ones associated with prostate cancer. The purpose of this study was to retrospectively analyze the incremental diagnostic value of 18F-DCFPyL dual-time imaging in patients with prostate cancer. METHOD: 114 prostate-related malignant lesions and 43 benign lesions in 38 patients with prostate cancer were retrospectively analyzed. Maximum standardized uptake value (SUVmax) for benign and prostate-related malignant lesions were calculated at min 60 and min 120 of PET/CT imaging. In order to calculate SUV ratio, the SUVmax of left gluteus maximus was measured at the same time. The difference of SUVmax metrics and SUV ratio between malignant and benign lesions was statistically analyzed, the cut-off value of ROC curve was calculated, and the diagnostic efficacy of SUVmax index and SUV ratio at two time points was compared. RESULTS: SUVmax metrics and SUV ratio of early and delayed imaging of PC-related malignant lesions were significantly higher than those of benign lesions (p < 0.05). In terms of individual indicators, the highest accuracy and sensitivity was in the delayed SUV ratio (89.2% and 94.7%), the best specificity was in the early SUVmax (93.0%). When the individual and combined indicators were compared together, the SUV ratio in the delay period still showed the best diagnostic sensitivity and accuracy, and the best specificity were SUVmax early and ▵SUVmax, SUVmax early and RI. CONCLUSIONS: Uptake of 18F-DCFPyL increased over time in prostate-associated malignant lesions compared with benign tissue. For single-phase imaging, 2-hour (delayed) imaging has better diagnostic performance. However, the dual-phase imaging (1 and 2 h) are helpful in the differential diagnosis of prostate-associated malignant lesions and benign lesions.

Modulation of cellular immunity by antibodies against calreticulin.

Although caltreticulin (CRT) is mainly a residential ER protein, it is also expressed on the membrane surface of various types of cells exhibiting multiple functions. We report here that intraperitoneal administration of a soluble recombinant CRT fragment (rCRT/39-272) led to a substantial decrease in delayed type hypersensitivity (DTH) responses in BALB/c mice and EAE in C57BL/6 mice. In the recall response against keyhole limpet hemocyanin (KLH) in vitro, draining lymph node cells from the rCRT/39-272-treated mice produced less IFN-γ but more IL-4 as compared with the cells from the control group. The immunomodulating effect of intraperitoneally administered rCRT/39-272 was attributed to anti-CRT Abs thereby induced, because, in passive transfer experiments, the CRT-specific antiserum could suppress DTH in BALB/c mice. B-cell-deficient µMT mice were not susceptible to rCRT/39-272-mediated DTH suppression. Furthermore, CRT appears on the surface of murine T cells soon after activation and remains detectable (at relatively low level) by flow cytometry for approximately 5 days in vitro. Anti-CRT Abs were able to inhibit AKT phosphorylation, proliferation, and cytokine production by activated murine T cells. We propose that cell surface CRT could play a role in the function of effector T cells and may be considered a target for immunological manipulation.

Functional analysis of recombinant calreticulin fragment 39-272: implications for immunobiological activities of calreticulin in health and disease.

Although calreticulin (CRT) is a major Ca(2+)-binding luminal resident protein, it can also appear on the surface of various types of cells and it functions as an immunopotentiating molecule. However, molecular mechanisms underlying the potent immunobiological activity of cell surface CRT are still unclear. In the present study, a recombinant fragment (rCRT/39-272) covering the lectin-like N domain and partial P domain of murine CRT has been expressed in Escherichia coli. The affinity-purified rCRT/39-272 assembles into homodimers and oligomers in solution and exhibits high binding affinity to various glycans, including carrageenan, alginic acids, and hyaluronic acids. Functionally, rCRT/39-272 is capable of driving the activation and maturation of B cells and cytokine production by macrophages in a TLR-4-dependent manner in vitro. It specifically binds recombinant mouse CD14, but not BAFFR and CD40. It is also able to trigger Ig class switching by B cells in the absence of T cell help both in vitro and in vivo. Furthermore, this fragment of CRT exhibits strong adjuvanticity when conjugated to polysaccharides or expressed as part of a fusion protein. Soluble CRT can be detected in the sera of patients with rheumatoid arthritis or systemic lupus erythematosus, but not in healthy subjects. We argue that CRT, either on the membrane surface of cells or in soluble form, is a potent stimulatory molecule to B cells and macrophages via the TLR-4/CD14 pathway and plays important roles in the pathogenesis of autoimmune diseases.