Eye Disease Prevalence and VF-14 Validation Among Patients Experiencing Homelessness and Presenting for Ophthalmic Examination in Baltimore, Maryland

Purpose

The coronavirus disease 2019 (COVID-19) pandemic is projected to drive 1.5 million Americans toward homelessness, adding to the 3.5 million currently affected. Homelessness poses both socioeconomic and public health challenges because housing status is a social determinant of health. Given ophthalmic health's importance in daily functioning, we characterized ophthalmic disease and vision-related quality of life (VRQOL) among a population experiencing homelessness in Baltimore, Maryland.

Methods

Questionnaires, including a Visual Function Index-14 (VF-14) for measuring VRQOL, were administered among patients seeking eye examinations at Health Care for the Homeless (HCH) from October 2018 to March 2020.

Results

One hundred sixty-two participants were enrolled in this study. The average age was 53 years. Participants' most common vision concerns were blurry vision (70%) and desire for glasses (52%). Best corrected visual acuity (BCVA) measurements revealed significant vision loss (18%, P < 0.001). Physicians mostly diagnosed refractive error (77%), cataracts (36%), glaucoma/glaucoma suspect (25%), and dry eye (24%). Nearly half were referred to additional ophthalmic care (46%). VRQOL trends reflected functional vision categories (P = 0.042 and P = 0.021). The 1:1 VRQOL and BCVA comparison showed correlation (rho = -0.3, P < 0.001). Cronbach's alpha demonstrated VF-14 reliability (alpha = 0.92).

Conclusions

We find high ophthalmic disease prevalence within a population experiencing homelessness. Comparison to studies worldwide reveals healthcare disparities despite healthcare system differences, suggesting a need for more targeted solutions. VF-14 is valid and reliable in assessing those experiencing homelessness. Intragroup VRQOL comparisons may reveal subgroup needs. It is imperative that future studies continue monitoring those experiencing homelessness.

Translational Relevance

Validation of VF-14 will allow future studies to utilize this patient-oriented metric within populations experiencing homelessness.

Epstein-Barr virus (EBV) hyperimmune globulin isolated from donors with high gp350 antibody titers protect humanized mice from challenge with EBV

Primary infection with Epstein-Barr virus (EBV) is associated with post-transplant lymphoproliferative disease and severe disease in patients with X-linked lymphoproliferative disease; no therapies are approved to prevent EBV infection in these patients. Hyperimmune globulin has been used to prevent some virus infections in immunocompromised persons. Here, we identified plasma donors with high titers of EBV gp350 and EBV B cell neutralizing antibodies. Pooled IgG isolated from these donors was compared to intravenous immunoglobulin (IVIG) for its ability to reduce viral load in the blood in humanized mice challenged with EBV. Mice that received EBV hyperimmune globulin had significantly reduced EBV DNA copy numbers compared to animals that received saline control; however, while animals that received EBV hyperimmune globulin had lower EBV DNA copies than those that received IVIG, the difference was not significant. Thus, while EBV hyperimmune globulin reduced viral load compared to IVIG, the effect was modest.

HIF-independent synthetic lethality between CDK4/6 inhibition and VHL loss across species

Inactivation of the VHL tumor suppressor gene is the signature initiating event in clear cell renal cell carcinoma (ccRCC), the most common form of kidney cancer, and causes the accumulation of hypoxia-inducible factor 2α (HIF-2α). HIF-2α inhibitors are effective in some ccRCC cases, but both de novo and acquired resistance have been observed in the laboratory and in the clinic. Here, we identified synthetic lethality between decreased activity of cyclin-dependent kinases 4 and 6 (CDK4/6) and VHL inactivation in two species (human and Drosophila) and across diverse human ccRCC cell lines in culture and xenografts. Although HIF-2α transcriptionally induced the CDK4/6 partner cyclin D1, HIF-2α was not required for the increased CDK4/6 requirement of VHL^-/- ccRCC cells. Accordingly, the antiproliferative effects of CDK4/6 inhibition were synergistic with HIF-2α inhibition in HIF-2α-dependent VHL^-/- ccRCC cells and not antagonistic with HIF-2α inhibition in HIF-2α-independent cells. These findings support testing CDK4/6 inhibitors as treatments for ccRCC, alone and in combination with HIF-2α inhibitors.

Resolution of new daily persistent headache by a tumor necrosis factor alpha antagonist, Venlafaxine

New daily persistent headache is a continuous, unremitting headache, notorious for its unresponsiveness to aggressive medical interventions. The underlying pathophysiology of new daily persistent headache is poorly understood resulting in unending, chronic pain. However, a prior study identified elevated tumor necrosis factor alpha within the cerebral spinal fluid of new daily persistent headache patients. Herein, we report on a patient who suffered with headache for 6 years failing to respond to over 20 different medical treatments, but found drastic improvement and eventual resolution with Venlafaxine. This drug binds to the 5-HT_2A receptor inhibiting tumor necrosis factor alpha signaling. Therefore, we hypothesize a chronic inflammatory mechanism driving new daily persistent headache pathology.

Immunization with Components of the Viral Fusion Apparatus Elicits Antibodies That Neutralize Epstein-Barr Virus in B Cells and Epithelial Cells

Epstein-Barr virus (EBV) causes infectious mononucleosis and is associated with epithelial-cell cancers and B cell lymphomas. An effective EBV vaccine is not available. We found that antibodies to the EBV glycoprotein gH/gL complex were the principal components in human plasma that neutralized infection of epithelial cells and that antibodies to gH/gL and gp42 contributed to B cell neutralization. Immunization of mice and nonhuman primates with nanoparticle vaccines that displayed components of the viral-fusion machinery EBV gH/gL or gH/gL/gp42 elicited antibodies that potently neutralized both epithelial-cell and B cell infection. Immune serum from nonhuman primates inhibited EBV-glycoprotein-mediated fusion of epithelial cells and B cells and targeted an epitope critical for virus-cell fusion. Therefore, unlike the leading EBV gp350 vaccine candidate, which only protects B cells from infection, these EBV nanoparticle vaccines elicit antibodies that inhibit the virus-fusion apparatus and provide cell-type-independent protection from virus infection.

Lamin A and microtubules collaborate to maintain nuclear morphology

Lamin A (LA) is a critical structural component of the nuclear lamina. Mutations within the LA gene (LMNA) lead to several human disorders, most striking of which is Hutchinson-Gilford Progeria Syndrome (HGPS), a premature aging disorder. HGPS cells are best characterized by an abnormal nuclear morphology known as nuclear blebbing, which arises due to the accumulation of progerin, a dominant mutant form of LA. The microtubule (MT) network is known to mediate changes in nuclear morphology in the context of specific events such as mitosis, cell polarization, nucleus positioning and cellular migration. What is less understood is the role of the microtubule network in determining nuclear morphology during interphase. In this study, we elucidate the role of the cytoskeleton in regulation and misregulation of nuclear morphology through perturbations of both the lamina and the microtubule network. We found that LA knockout cells exhibit a crescent shape morphology associated with the microtubule-organizing center. Furthermore, this crescent shape ameliorates upon treatment with MT drugs, Nocodazole or Taxol. Expression of progerin, in LA knockout cells also rescues the crescent shape, although the response to Nocodazole or Taxol treatment is altered in comparison to cells expressing LA. Together these results describe a collaborative effort between LA and the MT network to maintain nuclear morphology.

An Nlrc4 mutation associated with systemic hyperinflammation drives spontaneous non-hematopoietic IL-18 hyperproduction

Macrophage activation syndrome (MAS) is a life-threatening sepsis-like hyperinflammatory state arising in certain infectious and rheumatic diseases. Previous genetic associations have implicated genes critical for perforin-mediated cytotoxicity. However, we recently identified that activating mutations in inflammasome component NLRC4 lead to MAS and early-onset enterocolitis. Patients with NLRC4-MAS also have chronically and extraordinarily elevated serum IL-18. Notably, disease-causing mutations in other inflammasomes do not cause MAS or chronic IL-18 elevation.

In vitro, IL-1b production by THP1 cells expressing various NLRC4 patient mutations correlated with disease severity and identified pathogenic clusters in the molecular structure. To further study the function of NLRC4, we created a mouse bearing the T337S point mutation. Like NLRC4-MAS patients, NLRC4-T337S mice demonstrate elevated serum IL-18 in the absence of systemic inflammation. However, macrophages from NLRC4-T337S mice did not demonstrate enhanced IL-1β or IL-18 production. Correspondingly, bone marrow chimeras demonstrated that IL-18 hyperproduction was derived from non-hematopoietic cells. NLRC4-T337S mice did not demonstrate more severe disease in response to repeated systemic stimulation through TLR9 or TLR4, nor upon LCMV infection, but developed colitis with IL-10 receptor blockade. These results suggest intestinal epithelia, which express both NLRC4 and proIL-18, may be a source of pathogenic IL-18 in this model. Future work will clarify the source(s) of excessive IL-18 and identify how chronic IL-18 effects on gut homeostasis and T and NK cell responses may promote systemic hyperinflammation.

Methylene blue alleviates nuclear and mitochondrial abnormalities in progeria

Hutchinson–Gilford progeria syndrome (HGPS), a fatal premature aging disease, is caused by a single‐nucleotide mutation in the LMNA gene. Previous reports have focused on nuclear phenotypes in HGPS cells, yet the potential contribution of the mitochondria, a key player in normal aging, remains unclear. Using high‐resolution microscopy analysis, we demonstrated a significantly increased fraction of swollen and fragmented mitochondria and a marked reduction in mitochondrial mobility in HGPS fibroblast cells. Notably, the expression of PGC‐1α, a central regulator of mitochondrial biogenesis, was inhibited by progerin. To rescue mitochondrial defects, we treated HGPS cells with a mitochondrial‐targeting antioxidant methylene blue (MB). Our analysis indicated that MB treatment not only alleviated the mitochondrial defects but also rescued the hallmark nuclear abnormalities in HGPS cells. Additional analysis suggested that MB treatment released progerin from the nuclear membrane, rescued perinuclear heterochromatin loss and corrected misregulated gene expression in HGPS cells. Together, these results demonstrate a role of mitochondrial dysfunction in developing the premature aging phenotypes in HGPS cells and suggest MB as a promising therapeutic approach for HGPS.