Expansion of HIV-specific T follicular helper cells in chronic HIV infection

HIV targets CD4 T cells, which are required for the induction of high-affinity antibody responses and the formation of long-lived B cell memory. The depletion of antigen-specific CD4 T cells during HIV infection is therefore believed to impede the development of protective B cell immunity. Although several different HIV-related B cell dysfunctions have been described, the role of CD4 T follicular helper (TFH) cells in HIV infection remains unknown. Here, we assessed HIV-specific TFH responses in the lymph nodes of treatment-naive and antiretroviral-treated HIV-infected individuals. Strikingly, both the bulk TFH and HIV-specific TFH cell populations were significantly expanded in chronic HIV infection and were highly associated with viremia. In particular, GAG-specific TFH cells were detected at significantly higher levels in the lymph nodes compared with those of GP120-specific TFH cells and showed preferential secretion of the helper cytokine IL-21. In addition, TFH cell expansion was associated with an increase of germinal center B cells and plasma cells as well as IgG1 hypersecretion. Thus, our study suggests that high levels of HIV viremia drive the expansion of TFH cells, which in turn leads to perturbations of B cell differentiation, resulting in dysregulated antibody production.     

Differentiating between heat pain intensities: the combined effect of multiple autonomic parameters

Although it is well known that pain induces changes in autonomic parameters, the extent to which these changes correlate with the experience of pain is under debate. The aim of the present study was to compare a combination of multiple autonomic parameters and each parameter alone in their ability to differentiate among 4 categories of pain intensity. Tonic heat stimuli (1minute) were individually adjusted to induce no pain, low, medium, and high pain in 45 healthy volunteers. Electrocardiogram, photoplethysmogram, and galvanic skin response were recorded, and the following parameters were calculated: heart rate; heart rate variability-high frequency (0.15 to 0.4Hz) spectral power; skin conductance level; number of skin conduction fluctuations; and photoplethysmographic pulse wave amplitude. A combination of parameters was created by fitting an ordinal cumulative logit model to the data and using linear coefficients of the model. Friedman test with post-hoc Wilcoxon test were used to compare between pain intensity categories for every parameter alone and for their linear combination. All of the parameters successfully differentiated between no pain and all other pain categories. However, none of the parameters differentiated between all 3 pain categories (i.e., low and medium; medium and high; low and high). In contrast, the linear combination of parameters significantly differentiated not only between pain and no pain, but also between all pain categories (P<.001 to .02). These results suggest that multiparameter approaches should be further investigated to make progress toward reliable autonomic-based pain assessment.     

Hierarchical processing of face viewpoint in human visual cortex

The ability to recognize objects across different viewpoints (view invariance) is a remarkable property of the primate visual system. According to a prominent theory, view information is represented by view-selective mechanisms at early stages of visual processing and gradually becomes view invariant in high-level visual areas. Single-cell recording studies have also reported an intermediate step of partial view invariance for mirror-symmetric face views. Nevertheless, similar evidence for this type of hierarchical processing for face view has not been reported yet in the human visual cortex. The present functional magnetic resonance imaging study used state-of-the-art multivariate pattern analysis to explore face-view tuning in the human visual cortex. Our results revealed that consistent with a view-selective representation, face view can be successfully decoded in face and object-selective regions as well as in early visual cortex. Critically, similar neural representations for mirror-symmetric views were found in high-level but not in low-level visual areas. Our results support the notion of gradual emergence of view-invariant representation with invariance for mirror-symmetric images as an intermediate step and propose putative neural correlates of mirror-image confusion in the human brain.     

A Fc engineering approach to define functional humoral correlates of immunity against Ebola virus

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Co-existence of Myxobolus spp. (Myxozoa) in gray mullet (Mugil cephalus) juveniles from the Mediterranean Sea

Parasitology Research - Gray mullet (Mugilidae) occur in all seas and are farmed widely around the world, and thus, the risk of their parasites spreading through transport of aquaculture seed is a...     

Efficacy and safety of autologous hematopoietic cell transplantation in elderly patients with multiple myeloma: a retrospective national multi-site cohort study

We aimed to test the efficacy and toxicity of autologous hematopoietic cell transplant (HCT) in Multiple Myeloma (MM) patients aged ≥65 years compared to patients aged 60–64. Two hundred twenty consecutive patients (age ≥65, n = 87) with MM aged 60 and above, who underwent HCT as part of an upfront MM treatment, at four Israeli centers between 2000 and 2014 were included. A melphalan dose of 200 mg/m² was more frequent in the 60–64 age group vs. the ≥65 age group (77 vs. 57%, p = 0.002). There were no differences between groups in median day of neutrophil engraftment, incidence of infections, grades 3–4 mucositis, cardiovascular events, or non-relapse mortality at 100 days post HCT (4.7, vs. 5%, p = 0.9). A similar rate of improvement in response level was observed (36, vs. 35%, p = 0.87). At 3 years post HCT progression-free survival (PFS) was higher in the 60–64 age group (42 vs. 29%, p = 0.04); however, it was no longer so after adjustment for disease status prior to HCT (p = 0.49). In a Multivariate analysis, melphalan doses and age did not predict PFS. There was no difference in overall survival (OS) between age groups (p = 0.2). We conclude that toxicity profile, response, PFS, and OS of HCT in aged ≥65 patients with myeloma is similar to patients aged 60–64.