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Biology subjects

Hall, C. K.

Publications and source records attributed to Hall, C. K..

2 recordsLinked to original sources

Development of MHC Class I Blocking Peptides to Target Metabolic Dysfunction-Associated Steatohepatitis CD8+ T Cell Activation

MHC class I molecules play a crucial role in the immune system by presenting peptides derived from intracellular proteins to cytotoxic T lymphocytes (CTLs). This process is essential for immune surveillance and eliminating infected or malignant cells. In some diseases, the immune system fails to recognize and eliminate abnormal cells, leading to disease progression. Under conditions of metabolic dysfunction-associated steatohepatitis (MASH), subsets of CD8+ T cells have been identified as pathogenic, leading to inflammation and fibrosis. Therefore, explicitly targeting factors responsible for T cell activation may be necessary to prevent the onset of MASH and future complications such as cirrhosis or hepatocellular carcinoma. We have identified a specific MHC class I antigen that activates hepatic and splenic CD8+ T cells isolated from MASH mice. To specifically target the antigen, we developed two MHC H2-Kb blocking peptides, MHCP3 and MHCP5, that competitively inhibit the Ncf2 peptide from binding to H2-Kb and reduce activation and proliferation of CD8+ T cells. By inhibiting the recognition of specific antigens, these blocking peptides may prevent the activation of CD8+ T cells and progression of MASH.

immunology↗

Design of parallel ????-sheet nanofibrils using Monte-Carlo search, coarse-grained simulations, and experimental testing

Peptide self-assembly into amyloid fibrils provides numerous applications in drug delivery and biomedical engineering applications. We augment our previously-established computational screening technique along with experimental biophysical characterization to discover 7-mer peptides that self-assemble into "parallel {beta}-sheets", i.e., {beta}-sheets with N-terminus-to-C-terminus {beta}-strand vectors oriented in parallel. To accomplish the desired {beta}-strand organization, we applied the PepAD amino acid sequence design software to the Class-1 cross-{beta} spine defined by Sawaya et al. This molecular configuration includes two layers of parallel {beta}-sheets stacked such that N-terminus-to-C-terminus vectors are oriented antiparallel for molecules on adjacent {beta}-sheets. The first cohort of PepAD identified peptides were examined for their fibrillation behavior in DMD/PRIME20 simulations, and the top performing sequence was selected as a prototype for a subsequent round of sequence refinement. The two rounds of design resulted in a library of eight 7-mer peptides. In DMD/PRIME20 simulations, five of these peptides spontaneously formed fibril-like structures with a predominantly parallel {beta}-sheet arrangement, two formed fibril-like structure with <50% in parallel {beta}-sheet arrangement and one remained a random coil. Among the eight candidate peptides produced by PepAD and DMD/PRIME20, five were synthesized and purified. All five assembled into amyloid fibrils composed of parallel {beta}-sheets based on Fourier Transform Infrared Spectroscopy, Circular Dichroism, Electron Microscopy, and Thioflavin-T fluorescence spectroscopy measurements.

bioengineering↗