Therapeutic blockade of activin-A improves NK cell function and antitumor immunity

Natural killer (NK) cells are innate lymphocytes that play a major role in immunosurveillance against tumor initiation and metastatic spread. The signals and checkpoints that regulate NK cell fitness and function in the tumor microenvironment are not well defined. Transforming growth factor-β (TGF-β) is a suppressor of NK cells that inhibits interleukin-15 (IL-15)-dependent signaling events and increases the abundance of receptors that promote tissue residency. Here, we showed that NK cells express the type I activin receptor ALK4, which, upon binding to its ligand activin-A, phosphorylated SMAD2/3 to suppress IL-15-mediated NK cell metabolism. Activin-A impaired human and mouse NK cell proliferation and reduced the production of granzyme B to impair tumor killing. Similar to TGF-β, activin-A also induced SMAD2/3 phosphorylation and stimulated NK cells to increase their cell surface expression of several markers of ILC1 cells. Activin-A also induced these changes in TGF-β receptor-deficient NK cells, suggesting that activin-A and TGF-β stimulate independent pathways that drive SMAD2/3-mediated NK cell suppression. Last, inhibition of activin-A by follistatin substantially slowed orthotopic melanoma growth in mice. These data highlight the relevance of examining TGF-β-independent SMAD2/3 signaling mechanisms as a therapeutic axis to relieve NK cell suppression and promote antitumor immunity.

Objective measurement of erythema in psoriasis using digital color photography with color calibration

BACKGROUND

Traditional metrics for evaluating the severity of psoriasis are subjective, which complicates efforts to measure effective treatments in clinical trials.

METHODS

We collected images of psoriasis plaques and calibrated the coloration of the images according to an included color card. Features were extracted from the images and used to train a linear discriminant analysis classifier with cross-validation to automatically classify the degree of erythema. The results were tested against numerical scores obtained by a panel of dermatologists using a standard rating system.

RESULTS

Quantitative measures of erythema based on the digital color images showed good agreement with subjective assessment of erythema severity (κ = 0.4203). The color calibration process improved the agreement from κ = 0.2364 to κ = 0.4203.

CONCLUSION

We propose a method for the objective measurement of the psoriasis severity parameter of erythema and show that the calibration process improved the results.

Three-dimensional assessment of the effects of extraction and nonextraction orthodontic treatment on the face

The purpose of this prospective study was to compare the 3-dimensional (3-D) effects on the face of extraction and nonextraction orthodontic treatment in patients with skeletal Class I patterns. The sample of 24 patients included 12 whose treatment included extractions and 12 who were treated without extractions. Pretreatment study casts were assessed to evaluate dental differences between the 2 groups. Pretreatment and posttreatment lateral cephalograms and optical surface scans were also compared. In the lateral cephalometric assessment, the only significant (P <.05) pretreatment difference was lower lip length. Posttreatment, the nasolabial angle and lower lip thickness were significantly different (P <.05). Registration of the average 3-D optical surface scans indicated that, before treatment, the nonextraction group had longer and broader faces by 5 to 7 mm, and the upper lip and labiomental fold were 3 to 5 mm farther forward than in the extraction group. Posttreatment, the nonextraction group still had larger faces, but the difference was smaller. Faces in the extraction group became relatively more protrusive with treatment. The surface shape analysis technique showed that the cheeks were flatter in the nonextraction group at the start of treatment, but this reversed with time. In the extraction group, the concavity of the labiomental fold increased, while the nonextraction group showed no change in this area. The study demonstrates that 3-D optical surface scans offer more data for analysis compared with lateral cephalograms alone. It also highlights the changes that can be detected with surface shape analysis.

An evaluation of the Faces Pain Scale with young children

The psychometric characteristics of the Faces Pain Scale (FPS) were evaluated in three groups of preschool and school-aged children (3. 5-4.5; 4.5-5.5 and 5.5-6.5 years, respectively). The FPS was adequately comprehended by even young children. It was easily administered and was valid and discriminating. It did not, however, possess the linear scalability claimed by its authors.

The nature and development of nonverbal implicit memory

The study investigated the course of developmental changes in performance on nonverbal implicit and explicit memory tests and examined the degree to which implicit memory performance is dependent upon the storage of specific perceptual information. Four-, 5-, and 10-year-old children were required to name fragmented pictures of common objects or to name and answer general knowledge questions about complete versions of the same pictures. After a 48-h retention interval, all subjects were presented with a fragmented picture identification task containing pictures identical to those present during encoding (old), pictures which were from the same basic category as the study items but which varied in their perceptual similarity to those items (same), and novel pictures which were visually and semantically unrelated to the study items (new). The amount of visual information needed to name each item (picture identification threshold) was recorded. Following identification, subjects were asked whether or not they had been shown the picture previously. All age groups showed significant priming such that the picture identification threshold for the old items was lower than that of the new pictures. A smaller but significant priming effect was obtained for the same-name items. This effect was maximized when the same-name items were perceptually similar to the study items. The magnitude of these priming effects did not vary as a function of age, but greater priming was found for those children who identified picture fragments during the study phase. In contrast, the sensitivity of recognition memory performance increased from 4 to 10 years of age. These results suggest that the processes that subserve pictorial repetition priming and recognition memory develop at different rates and that such priming is dependent upon access to specific perceptual representations of studied objects.

Ponzo Perspective Illusion as a Manifestation of Space Perception

The Ponzo perspective illusion, a special case of space perception, is influenced by contextual factors, texture, stereopsis, and familiarity in addition to perspective cues. The importance of familiarity is demonstrated by cultural differences obtained with photographs of natural settings which emphasize depth cues.