Validation of Metallothionein Immunohistochemistry as a Highly Sensitive Screening Test for Wilson Disease.

Wilson's disease (WD) is a rare autosomal recessive condition with protean clinical manifestations that results from biallelic ATP7B mutations. However, non-destructive tissue tests to be applied clinically to tissue specimens are not widely available to effectively assess patients for possible WD. Previously, we showed that metallothionein (MTH) immunohistochemistry has a high sensitivity and specificity for WD diagnosis and, thus, represents a potentially powerful diagnostic tool that can be used in routine histologic sections. We sought to validate this finding in a large cohort of bona fide WD patients and to correlate metallothionein expression with other histologic features. We identified 91 cases of WD, which included 28 needle biopsies and 64 explants from 14 centers worldwide. Histologic features were evaluated, and a histopathological pattern was assigned to each case. All cases were evaluated with Masson trichrome and MTH immunohistochemistry (clone UC1MT, Abcam) using previously published technique. Liver tissues from chronic cholestatic diseases (n= 42) were used as controls. The median age of the cohort was 28.5 years. Out of 91 total cases, 83 were positive for MTH immunostain. In the controls, all 42 cases were negative for MTH immunostain. The sensitivity and specificity of MTH immunostain for WD were 91.20% and 100%, respectively. MTH immunohistochemistry is a highly sensitive and specific cost-effective screening tool for WD. It can be used for patients across age groups, varied histologic patterns, and fibrosis stages. This marker could prove to be a valuable tool in the evaluation of patients with possible WD.

Digital Hepatic Iron Content: An Artificial Intelligence Model for Spatially Resolved Histologic Iron Quantitative Analysis in Liver Samples.

Currently, the precise evaluation of tissue hepatic iron content (HIC) requires laboratory testing using tissue-destructive methods based on colorimetry or spectrophotometry. To maximize the use of routine histologic stains in this context, we developed an artificial intelligence (AI) model for the recognition and spatially resolved measurement of iron in liver samples. Our AI model was developed using a cloud-based, supervised deep learning platform (Aiforia Technologies). Using digitized Pearl Prussian blue iron stain whole slide images representing the full spectrum of changes seen in hepatic iron overload, our training set consisted of 59 cases, and our validation set consisted of 19 cases. The study group consisted of 98 liver samples from 5 different laboratories, for which tissue quantitative analysis using inductively coupled plasma mass spectrometry was available, collected between 2012 and 2022. The correlation between the AI model % iron area and HIC was Rs = 0.93 for needle core biopsy samples (n = 73) and Rs = 0.86 for all samples (n = 98). The digital hepatic iron index (HII) was highly correlated with HII > 1 (area under the curve [AUC] = 0.93) and HII > 1.9 (AUC = 0.94). The percentage area of iron within hepatocytes (vs Kupffer cells and portal tract iron) identified patients with any hereditary hemochromatosis-related mutations (either homozygous or heterozygous) (AUC = 0.65, P = .01) with at least similar accuracy than HIC, HII, and any histologic iron score. The correlation between the Deugnier and Turlin score and the AI model % iron area for all patients was Rs = 0.87 for total score, Rs = 0.82 for hepatocyte iron score, and Rs = 0.84 for Kupffer cell iron score. Iron quantitative analysis using our AI model was highly correlated with both detailed histologic scoring systems and tissue quantitative analysis using inductively coupled plasma mass spectrometry and offers advantages (related to the spatial resolution of iron analysis and the nontissue-destructive nature of the test) over standard quantitative methods.

TRPM8 as the rapid testosterone signaling receptor: Implications in the regulation of dimorphic sexual and social behaviors.

Testosterone regulates dimorphic sexual behaviors in all vertebrates. However, the molecular mechanism underlying these behaviors remains unclear. Here, we report that a newly identified rapid testosterone signaling receptor, Transient Receptor Potential Melastatin 8 (TRPM8), regulates dimorphic sexual and social behaviors in mice. We found that, along with higher steroid levels in the circulation, TRPM8-/- male mice exhibit increased mounting frequency indiscriminate of sex, delayed sexual satiety, and increased aggression compared to wild-type controls, while TRPM8-/- females display an increased olfaction-exploratory behavior. Furthermore, neuronal responses to acute testosterone application onto the amygdala were attenuated in TRPM8-/- males but remained unchanged in females. Moreover, activation of dopaminergic neurons in the ventral tegmental area following mating was impaired in TRPM8-/- males. Together, these results demonstrate that TRPM8 regulates dimorphic sexual and social behaviors, and potentially constitutes a signalosome for mediation of sex-reward mechanism in males. Thus, deficiency of TRPM8 might lead to a delayed sexual satiety phenomenon.