Proteomic features of gray matter layers and superficial white matter of the rhesus monkey neocortex: comparison of prefrontal area 46 and occipital area 17.

In this novel large-scale multiplexed immunofluorescence study we comprehensively characterized and compared layer-specific proteomic features within regions of interest of the widely divergent dorsolateral prefrontal cortex (A46) and primary visual cortex (A17) of adult rhesus monkeys. Twenty-eight markers were imaged in rounds of sequential staining, and their spatial distribution precisely quantified within gray matter layers and superficial white matter. Cells were classified as neurons, astrocytes, oligodendrocytes, microglia, or endothelial cells. The distribution of fibers and blood vessels were assessed by quantification of staining intensity across regions of interest. This method revealed multivariate similarities and differences between layers and areas. Protein expression in neurons was the strongest determinant of both laminar and regional differences, whereas protein expression in glia was more important for intra-areal laminar distinctions. Among specific results, we observed a lower glia-to-neuron ratio in A17 than in A46 and the pan-neuronal markers HuD and NeuN were differentially distributed in both brain areas with a lower intensity of NeuN in layers 4 and 5 of A17 compared to A46 and other A17 layers. Astrocytes and oligodendrocytes exhibited distinct marker-specific laminar distributions that differed between regions; notably, there was a high proportion of ALDH1L1-expressing astrocytes and of oligodendrocyte markers in layer 4 of A17. The many nuanced differences in protein expression between layers and regions observed here highlight the need for direct assessment of proteins, in addition to RNA expression, and set the stage for future protein-focused studies of these and other brain regions in normal and pathological conditions.

Family Perspectives on Clinical Research for Pediatric Multiple Sclerosis: Enhancing Equity.

Pediatric new drug trials are federally mandated, but family perspectives in multiple sclerosis (MS) research are limited. Due to MS chronicity and long-term medical system involvement, we obtained family views on research priorities and optimized methods for future studies. Focus groups were convened with families impacted by pediatric-onset MS. Recruitment included those followed by the Network of Pediatric MS Centers, geographically disparate locations, and centers' voluntary election. Study questions included: healthcare experiences, clinical trials perspectives, cognitive/psychosocial/educational outcomes, disease course and disability accrual. All subjects supported future clinical studies. Patients highlighted contribution to knowledge base but were wary of experimental medication and disease-course impeding activities. Parents underscored medication delivery modalities, side-effects, and limiting children's discomfort. All wanted study relevance made explicit. Suggested future study design elements included: providing compensation, limiting assumptions regarding outcome linkages, understanding study-related psychological impacts, and reducing participation burdens. Rare disease research can assist general medicine diagnosis and referral. Variable study designs and explicit rationale may augment participation. Closing the pediatric research gap requires family engagement in the research process.