Biology subjects

Hamm-Alvarez, S. F.

Publications and source records attributed to Hamm-Alvarez, S. F..

3 recordsLinked to original sources

bioRxiv2026

Tear Proteomics Reveals RAGE and NLRP3 Inflammasome Pathway Activation in Lacrimal Glands of a Sjögren's Disease Mouse Model

PurposeTo characterize tear proteome changes in male non-obese diabetic (NOD) mice with Sjogrens disease (SjD)-like autoimmune dacryoadenitis and determine whether identified tear proteins are associated with lacrimal gland (LG) pathogenesis. MethodsTears were collected from 14-week-old male NOD mice and age-matched male BALB/c controls and analyzed by tandem mass tag (TMT)-based liquid chromatography tandem mass spectrometry (LC-MS/MS). Differentially expressed proteins (DEPs) were defined using adjusted P < 0.05 and absolute fold change > 1.5. Functional enrichment analysis was performed using Enrichr. Selected upregulated DEPs were further examined in tear and LG samples from independent mouse cohorts using Western blotting, immunofluorescence, and RT-qPCR. ResultsA total of 142 proteins were quantified across all tear samples. Hierarchical clustering and principal component analysis (PCA) separated NOD from BALB/c tear proteomes. A total of 41 proteins were differentially expressed in NOD mouse tears (33 increased, 8 decreased). Increased tear proteins were enriched in immune and inflammatory responses, secretory compartments, RAGE receptor binding, glutathione metabolism, oxidative stress, and redox regulation. S100A8/A9, GSTO1-1, Gal-3, and pIgR/secretory component (SC) were increased in both NOD mouse tears and LG. In NOD LG, increased S100A8/A9 was accompanied by elevated RAGE, whereas increased GSTO1-1 was associated with increased NLRP3, cleaved caspase-1, cleaved gasdermin, cleaved IL-1{beta}, and increased Il1b, Il18, and Il18r gene expression. ConclusionsMale NOD mouse tears contain disease-related proteins reflecting pathological inflammatory and epithelial changes in the LG including increased RAGE signaling, NLRP3 inflammasome activation, and altered epithelial transcytosis.

immunology↗

bioRxiv2024

Serum and Tear Autoantibodies from NOD and NOR Mice as Potential Diagnostic Indicators of Local and Systemic Inflammation in Sjögren's Disease

BackgroundSjogrens Disease (SjD) is an autoimmune disease characterized by lymphocytic infiltration of salivary and lacrimal glands (LG). The LG produces the protein-rich aqueous component of tears, and SjD-associated autoimmune dacryoadenitis (AD) may thus alter tear autoantibody composition. MethodsThe presence of tertiary lymphoid structures (TLS) in LG from two murine models of SjD-associated AD, male NOD and male NOR mice, were evaluated using immunofluorescence. IgG and IgA reactivity in serum and tears from these models were probed in three studies against a panel of 80-120 autoantigens using autoantibody microarrays relative to serum and tears from healthy male BALB/c mice. Data were analyzed by R package Limma. ResultsAnalysis of immunofluorescence in LG sections from both SjD models showed TLS. Only one autoantibody was significantly elevated in tears and serum in both SjD models across all studies. Three autoantibodies were significantly elevated in serum but not in tears in both SjD models across all studies. Conversely, six IgG and thirteen IgA autoantibodies (6 sharing the same autoantigen) were significantly elevated in tears but not serum in both SjD models. ConclusionNOD and NOR mice with SjD-associated AD have distinct autoantibody profiles in tears and serum. Tear IgA isotype autoantibodies showed a greater diversity than tear IgG autoantibodies. TLS observed in LG are a likely source of the tear autoantibodies.

immunology↗

bioRxiv2024

WAVE1 and WAVE2 facilitate human papillomavirus-driven actin polymerization during cellular entry

Human Papillomavirus Type 16 (HPV16) is an etiological agent of human cancers that requires endocytosis to initiate infection. HPV16 entry into epithelial cells occurs through a non-canonical endocytic pathway that is actin-driven, but it is not well understood how HPV16-cell surface interactions trigger actin reorganization in a way that facilitates entry. This study provides evidence that Wiskott-Aldrich syndrome protein family verprolin-homologous proteins 1 and 2 (WAVE1 and WAVE2) are molecular mediators of the actin polymerization that facilitates HPV endocytosis and intracellular trafficking. We demonstrate through post-transcriptional gene silencing and genome editing that WAVE1 and WAVE2 are critical for efficient HPV16 infection, and that restoration of each in knockout cells rescues HPV16 infection. Cells lacking WAVE1, WAVE2, or both, internalize HPV16 at a significantly reduced rate. Analysis of fluorescently labeled cells exposed to HPV16 and acquired by confocal fluorescence microscopy revealed that HPV16, WAVE1, WAVE2, and actin are all colocalized at the cellular dorsal surface. We also found that HPV16 stimulates WAVE1 and WAVE2-mediated cellular dorsal surface filopodia formation during the viral endocytic process. Taken together, this study provides evidence that the HPV endocytic process needed for infection is controlled by actin reorganization into filopodial protrusions and that this process is mediated by WAVE1 and WAVE2. Author SummaryHuman Papillomavirus (HPV) is the most common sexually transmitted infection in the United States. While its mode of entry into cells has yet to be fully described, extensive studies indicate HPV entry occurs via a macropinocytosis-like pathway. Interestingly, more than 10 viruses enter cells via macropinocytosis-like entry, with no two viruses utilizing identical factors for entry. It is unclear whether these viruses are entering cells via the same pathway, or if the term "macropinocytosis" describes a subset of endocytic pathways. One unifying feature of entry for each of these viruses is their requirement of actin polymerization. In this study, we identify the cellular factors necessary for actin polymerization to participate in HPV endocytosis. The findings of this study are of importance to the field of virology as they may extend to the infection of other viruses. It is also of interest in cancer studies as macropinocytosis has been associated with the scavenging of nutrients and methuosis, a form of cell death in cancer cells that occurs from over- scavenging. Nanoparticle delivery can also occur via macropinocytosis. Therefore, the contribution of WAVE proteins to macropinocytosis and macropinocytosis-like endocytic events is informative to a broad audience.

cell biology↗