Medical Pathology Commons^™

Rocatinlimab As A Novel Treatment Strategy For Atopic Dermatitis, Haylee Whyde, Evan Blazek, Macy Davis, Parker George, Alex Lowery, Connor Dains, Brenna Hissong, David Koh

Pharmacy and Wellness Review

Atopic dermatitis is a common chronic inflammatory skin disease that affects millions of children and adults in the United States. Atopic dermatitis is characterized by recurrent pruritus, erythema, and relapsing symptoms that can significantly impair quality of life. The pathophysiology of atopic dermatitis involves epidermal barrier dysfunction, immune dysregulation, and genetic susceptibility. Atopic dermatitis guidelines follow a stepwise approach that begins with a severity assessment, trigger avoidance, and nonpharmacologic and pharmacologic treatments. First-line therapies include topical corticosteroids (TCSs), topical calcineurin inhibitors (TCIs), and emollients. Crisaborole and topical ruxolitinib are used for mild-to-moderate disease when prior therapy has been inadequate. Monoclonal …

Comparison Of Fully Covered Self-Expandable Metal Biliary Stents With Or Without Anchoring Double-Pigtail Plastic Stents: A Systematic Review And Meta-Analysis, Samuel Tanner, Fadi Hawa, Alejandra Vargas, Priyata Dutta, Antonio Facciorusso, Jean M. Chalhoub, Jorge D. Machicado

Department of Medicine Faculty Publications

Background and AIMS

Fully covered self-expandable metal stents (FcSEMSs) have become the mainstay of treatment for a variety of biliary pathologies. However, FcSEMSs have been associated with a greater rate of stent migration than other types of stents. A technique of anchoring double-pigtail plastic stents (DPPSs) has been proposed to minimize migration of biliary FcSEMSs. Herein, we evaluated the efficacy of anchoring DPPSs among patients treated with biliary FcSEMSs.

Methods

We performed a systematic review using PubMed, EMBASE, and Web of Science from database inception through August 2023. Full-text articles comparing FcSEMSs with or without anchoring DPPSs were included. We …

Educational Case: Meningioma, Ashley M. Carter, Harrison Dai, Harrison Klause, Alberto Musto, Richard M. Conran

Department of Medicine Faculty Publications

The following fictional case is intended as a learning tool within the Pathology Competencies for Medical Education (PCME), a set of national standards for teaching pathology. These are divided into three basic competencies: Disease Mechanisms and Processes, Organ System Pathology, and Diagnostic Medicine and Therapeutic Pathology.

Stat4-Dependent Regulation Of Neuroinflammation In Atherosclerosis, Natalie Stahr, Alina K. Moriarty, Shelby D. Ma, W. Coles Keeter, Woong-Ki Kim, Larry D. Sanford, Elena V. Galkina

Department of Biomedical and Translational Sciences Faculty Publications

Atherosclerosis is linked to an increased risk of cognitive decline, with chronic inflammation being a common feature of both pathologies. IL-12 activates STAT4 to regulate myeloid cell functions, and blockade of this pathway alleviates cognitive impairment in Alzheimer's models. However, the mechanisms connecting vascular pathology to neuroinflammation remain unclear. Here, we examine whether STAT4 functions as a common mediator of neuroinflammation in atherosclerosis. We demonstrate that LysM^Cre-specific STAT4 deficiency ameliorates deficits in long-term memory in low-density lipoprotein-deficient (Ldlr^-/-) mice fed a high-fat diet (HFD-C). STAT4 deficiency moderately reduces Ser199-phosphorylated Tau burden. Atherosclerosis alters brain immune …

Lipid And Foam Cell Accumulation As Novel Pathological Features Of Benign Prostatic Hyperplasia, Dita Julianingsih, Samara V. Silver, Thaissa Horne, Kasun Gunawardena, Savannah Ward, Alicia Malewska, Douglas Strand, Julius Nyalwidhe, Ilya Sobol, Petra Popovics

Department of Biomedical and Translational Sciences Faculty Publications

Background

Benign prostatic hyperplasia (BPH) encompasses a heterogeneous set of pathological processes that instigate lower urinary tract symptoms (LUTS). Using a mouse model of steroid hormone imbalance-induced lower urinary tract dysfunction, we identified luminal lipid-laden foamy macrophages, although their presence and contribution to human pathology have not yet been established. The objective of this study was to determine whether luminal macrophages are associated with human BPH and to assess how lipid accumulation relates to underlying pathological features and clinical parameters.

Methods

Whole-mount tissue sections from simple prostatectomy specimens and prostates from healthy donors were used to evaluate the association of …

Corticobasal Syndrome With Mixed Pathology In The Absence Of Grn Mutation: A Clinico-Pathological Case Of Ftld-Tdp With Coexisting Alzheimer’S And Lewy Body Pathology, Hugo Zamarron, David Irwin, Jeffery Phillips, Edward Lee, Matthew Tisdall, Corey Mcmillan

Research Colloquium

Background: Corticobasal syndrome (CBS) is a neurodegenerative disorder characterized by often asymmetric fronto-pariteal and extra-pyramidal features that is traditionally associated with tauopathy, but pathological findings are heterogenous, including other forms of frontotemporal lobar degeneration (FTLD) and mixed pathologies of aging. We present clinical, radiographic, and histopathologic features of asymmetry in a unique patient with CBS and underlying FTLD with TDP-43 pathology (FTLD-TDP), co-occurring with other age-related pathologies.

Case Presentation: A 76-year-old man presented with progressive cognitive and motor dysfunction including asymmetric parkinsonism, left-sided dystonia and rigidity, apraxia, visuospatial impairment, and a subtle social disorder including apathy and social withdrawal. The …

Pseudomonas Aeruginosa Exoenzyme Y Enzymatic Activity Inhibits Exoenzyme S-Induced Caspase Activation But Not Cytotoxicity In Pulmonary Microvascular Endothelial Cells, Connor Holm

Honors Theses

Pseudomonas aeruginosa (P. aeruginosa) is the most common cause of ventilator-associated pneumonia in intensive care unit patients. P. aeruginosa utilizes a type III secretion system that injects exoenzymes U, S, T, and/or Y into the host cell cytosol. A majority of clinically isolated P. aeruginosa strains express ExoY often in combination with ExoU and ExoT, or ExoS and ExoT. Host signaling mechanisms in response to intoxication with individual exoenzymes have been extensively studied, yet little is known about host cell response to co-intoxication. In this study, pulmonary microvascular endothelial cells (PMVECs) were infected with P. aeruginosa strains expressing different combinations …

An Analytical Model Of Motion Artifacts In A Measured Arterial Pulse Signal—Part I: Accelerometers And Ppg Sensors, Md Mahfuzur Rahman, Subodh Toraskar, Mamun Hasan, Zhili Hao

Mechanical & Aerospace Engineering Faculty Publications

This paper, the first of two parts, presents an analytical model of motion artifacts (MAs) in measured pulse signals by accelerometers and photoplethysmography (PPG) sensors. As the transmission path from the true pulse signal in an artery to the sensor output (measured pulse signal), the tissue-contact-sensor (TCS) stack is modeled as a 1DOF (degree-of-freedom) system. MAs cause baseline drift of the mass and simultaneously time-varying system parameters (TVSPs) of the TCS stack. With arterial wall displacement and pulsatile pressure serving separately as the true pulse signal, an analytical model is developed to mathematically relate baseline drift and TVSP to a …

Socioeconomic Status And Health Disparities Drive Differences In Accelerometer-Derived Physical Activity In Fatty Liver Disease And Significant Fibrosis, Lucia Tabacu, Sajag Swami, Mark Ledbetter, Mohamad S. Siddiqui, Ekaterina Smirnova

Mathematics & Statistics Faculty Publications

Background and aims

The cornerstone of clinical management of patients with nonalcoholic fatty liver disease (NAFLD) are lifestyle changes such as increasing physical activity (PA) aimed at improving cardiometabolic risk. To inform NAFLD prevention and treatment guidelines we aimed to: (i) quantify the role of PA on lowering the risk for NAFLD and fibrosis; (ii) characterize NAFLD and fibrosis association with PA in the context of socioeconomic environment.

Methods

A sample of 2648 participants from the NHANES 2003–2006 was selected to develop survey weighted multivariable logistic regression models for predicting NAFLD and significant fibrosis, diagnosed non-invasively via fatty liver index …

Extending The Gift—Utilizing Residual Human Anatomical Materials For Training Pathologists' Assistants In Surgical Pathology Techniques, Kerwin M. Kolheffer, Lauren Yoho, Matthew Myers, Ismail El Moudden

Department of Pathology & Anatomy Faculty Publications

This study investigates the effectiveness of using residual human anatomical materials, obtained from a gross anatomy course, for training Pathologists' Assistant (PathA) students in surgical pathology techniques. We utilized two surveys to assess the perceived efficacy of this approach: one survey targeted PathA students to evaluate their training experiences with both human and animal tissues, while the other assessed the impact of specimen collection on the educational experiences of gross anatomy course students.

Perioperative Risks Of The Patient With Heart Failure, Gabrielle Metoyer

Nursing Student Class Projects (Formerly MSN)

Perioperative Risks of the Patient with Heart Failure

Gabrielle Metoyer

Department of Nursing, Otterbein University

NURS 6810 – Advanced Pathophysiology

Dr. Deanna Batross and Dr. Shivani Bhatnagar

August 5, 2022

Abstract

According to the CDC (2020), heart failure occurs when the heart cannot pump enough blood and oxygen to support other organs in your body. Heart failure is an epidemic disease affecting 1-2% of the population worldwide (Schwinger, 2020). It is one of the leading causes of morbidity and mortality worldwide with an estimated 6.5 million adults with heart failure in the United States (Lo et al., 2021). Medical advances …

Design And Development Of Software With A Graphical User Interface To Display And Convert Multiple Microscopic Histology Images, Sayed Ahmadreza Razian, Majid Jadidi, Alexey Kamenskiy

UNO Student Research and Creative Activity Fair

Histological images are widely used to assess the microscopic anatomy of biological tissues. Recent advancements in image analysis allow the identification of structural features on histological sections that can help advance medical device development, brain and cancer research, drug discovery, vascular mechanobiology, and many other fields. Histological slide scanners create images in SVS and TIFF formats that were designed to archive image blocks and high-resolution textual information. Because these formats were primarily intended for storage, they are often not compatible with conventional image analysis software and require conversion before they can be used in research. We have developed a user-friendly …

Role Of Meibum And Tear Phospholipids In The Evaporative Water Loss Associated With Dry Eye., Samiyyah M. Sledge

Electronic Theses and Dissertations

It is generally believed that the tear film lipid surface film inhibits the rate of evaporation (Revap) of the underlying tear aqueous. It is also generally believed that changes in the composition of the tear film lipid layer is responsible for an increase in Revap in patients with dry eye. Both of these ideas have never been proven. The purpose of the current studies was to test these ideas. Revap was measured in vitro gravimetrically. Lipid spreading was measured using Raman spectroscopy and microscopy. The influence of the following surface films on the Revap of the sub phase of physiologically …

Gut Pathophysiology In Mouse Models Of Social Behavior Deficits, Kyla Scott

Undergraduate Honors Theses

Autism spectrum disorders (ASD) encompass neurodevelopment disorders characterized by atypical patterns of development that impact multiple areas of functioning beginning in early childhood. The etiology of ASD is unknown and there are currently no preventative treatment options. Gastrointestinal symptoms are commonly associated comorbidities. The microbiota-gut-brain axis is a multidirectional communication chain that connects the central and enteric nervous system that relates brain function to peripheral intestinal functions. Changes within this axis have been postulated in ASD. For example, the “leaky gut theory” proposes that chronic inflammation is linked to alterations in the bacterial profiles of the gut microbiome and subsequent …

Oral Contraceptives As Possible Acl Injury Prevention Method, Haley Schweizer

Capstone Showcase

ABSTRACT

Introduction: Anterior Cruciate Ligament (ACL) injuries are an upsetting setback for many athletes that require a long and costly recovery process. The injury rates are four times greater in women than men. Preventative measures that help to prevent ACL injuries are limited to stretching and strengthening. Therefore, this review aims to investigate if oral contraceptive [I] usage provides a possible new avenue for prevention of ACL injury [O] in young female athletes (ages 18-30) [P] compared to those that do not take oral contraceptives [C].

Methods: A literature review was performed though PubMed, Google Scholar, SCOPUS Database, and ClinicalKey …

Analyzing The Effects Of Opioids On Cortical Pore Networks In Rabbit Tibiae And Femora, Kassidy Wilson

Williams Honors College, Honors Research Projects

The following project was approved by the Institutional Animal Care and Use Committee (IACUC) (Protocol number #18-11-12 ARC). This study was completed as a subset of Dr. Andronowski's overarching lab project. Femora and tibiae were procured from New Zealand White rabbits to study the prolonged effects of opioid use in bone remodeling. This specific project analyzed the effects of opioids on the pore networks and the pore orientation.

Comparison Of Varying Tissue Freezing Methods On Murine Colonic Tissue, James Hughes

Biomedical Engineering Undergraduate Honors Theses

Histology often requires a tissue specimen to be embedded so that it may be sectioned, stained, and mounted on a microscope slide for viewing. One common method of tissue embedding for rapid histology is freezing, since freezing allows tissue to be stored without the need for fixing. Frozen tissue is often embedded in a medium such as Optimal Cutting Temperature (OCT) compound so that it can be sectioned using a cryostat. However, factors such as ice-crystal formation during the freezing process can cause damage to the tissue. As such, the protocol used to freeze the tissue can affect the quality …

Spinal Cord Trauma: An Overview Of Normal Structure And Function, Primary And Secondary Mechanisms Of Injury, And Emerging Treatment Modalities, Daniel Morin

Senior Honors Theses

The structures of the spinal cord and vertebral column are designed to provide flexibility, while still providing ample protection for the spinal cord deep within. While it does offer remarkable protection against most routine trauma, the spinal cord is still vulnerable to high-force etiologies of trauma and may become damaged as a result. These events are referred to as primary injury. Following the initial injury, the body’s own physiological responses cause a cascade of deleterious effects, known as secondary injury. Secondary injury is a major therapeutic target in mitigating the effects of spinal cord injury (SCI), and much research is …

Sedentary Time And The Cumulative Risk Of Preserved And Reduced Ejection Fraction Heart Failure: From The Multi-Ethnic Study Of Atherosclerosis, Brandi Scot Rariden

UNF Graduate Theses and Dissertations

ABSTRACT

Purpose: The purpose of this study was to examine the relationship between self-reported sedentary time (ST) and the cumulative risk of preserved ejection fraction heart failure (HFpEF) and reduced ejection fraction heart failure (HFrEF) using a diverse cohort of U.S. adults 45-84 years of age.

Methods: Using data from the Multi-Ethnic Study of Atherosclerosis (MESA), we identified 6,814 subjects (52.9% female). All were free of baseline cardiovascular disease. Cox regression was used to calculate the hazard ratios (HR) associated with baseline ST and risk of overall heart failure (HF), HFpEF, and HFrEF. Weekly self-reported ST was dichotomized …

Effect Of Hemiepiphysiodesis On The Growth Plate: The Histopathological Changes And Mechanism Exploration Of Recurrence In Mini Pig Model., Jing Ding, Jin He, Zhi-Qiang Zhang, Zhen-Kai Wu, Fang-Chun Jin

Manuscripts, Articles, Book Chapters and Other Papers

Purpose: Hemiepiphysiodesis has been widely used to correct angular deformity of long bone in immature patients. However, there is a limited knowledge about the biomechanical effect of this technique on the histopathological changes of the growth plate and the mechanism of recurrence of malformation after implant removal. We aimed to evaluate the biomechanical effect of hemiepiphysiodesis on the histopathological changes of the growth plate and the mechanism of recurrence of malformation after implant removal in Bama miniature pigs, and to explore the role of asymmetric stress during this procedure.

Methods: Eight 3-month-old male Bama miniature pigs sustained surgeries on the …

Novel Advances In Alzheimer's Disease, Jacob P. Naumann

The Downtown Review: An Interdisciplinary Journal Written and Peer-Reviewed by Mandel Honors College Students at Cleveland State University

Alzheimer’s disease, the most common form of dementia in adults, is a progressive degenerative neurological disease that affects memory, cognition, and behavior. Dr. Alois Alzheimer discovered and diagnosed the irreversible disease in 1906 after documenting the famous case of Auguste Deter.¹ Since the discovery of the disease, numerous advances have made it possible to not only better understand the causal factors, but also to improve the medical diagnosis and preventative measures that healthcare providers can implement. For the first time since 1984, the National Institute on Aging (NIAA) and the Alzheimer’s Association (AA) proposed and published new diagnostic guideline …

Tibial Tubercle Transfer To Correct Bilateral Patellar Tendinopathy In A Collegiate Football Player, Andrew D. Hamstra

Boise State University Theses and Dissertations

Objective: To present a case of a competitive football player with chronic patellar tendinopathy and the associated bilateral tibial tubercle transfer surgeries performed leading to the reduction of pain and return to participation.

Background: A 19 year-old male football athlete (height= 187.96 cm, mass= 112.037 kg) presented with chronic patellar tendinopathy that began in his high school career and continued to worsen with the increased physical demands associated with participation in collegiate sport.

Differential Diagnosis: Chondromalacia patella and Osgood Schlatters disease.

Treatment: After nonsurgical intervention resulted in no decrease of pain, bilateral tibial tubercle transfer surgery was conducted to correct …

How To Write An Article: Preparing A Publishable Manuscript!, Vinod B. Shidham, Martha B. Pitman, Richard M. Demay

Department of Pathology

Most of the scientific work presented as abstracts (platforms and posters) at various conferences have the potential to be published as articles in peer-reviewed journals. This DIY (Do It Yourself) article on how to achieve that goal is an extension of the symposium presented at the 36th European Congress of Cytology, Istanbul, Turkey (presentation available on net at http://alturl.com/q6bfp). The criteria for manuscript authorship should be based on the ICMJE (International Committee of Medical Journal Editors) Uniform Requirements for Manuscripts. The next step is to choose the appropriate journal to submit the manuscript and review the 'Instructions to …

Optimal Bone Strength And Mineralization Requires The Type 2 Iodothyronine Deiodinase In Osteoblasts, J. H. D. Bassett, Alan Boyde, Peter G. T. Howell, Richard H. Bassett, Thomas M. Galliford, Marta Archanco, Holly Evans, Michelle A. Lawson, Peter Croucher, Donald L. St. Germain, Valerie A. Galton, Graham R. Williams

Dartmouth Scholarship

Hypothyroidism and thyrotoxicosis are each associated with an increased risk of fracture. Although thyroxine (T4) is the predominant circulating thyroid hormone, target cell responses are determined by local intracellular availability of the active hormone 3,5,3'-L-triiodothyronine (T3), which is generated from T4 by the type 2 deiodinase enzyme (D2). To investigate the role of locally produced T3 in bone, we characterized mice deficient in D2 (D2KO) in which the serum T3 level is normal. Bones from adult D2KO mice have reduced toughness and are brittle, displaying an increased susceptibility to fracture. This phenotype is characterized by a 50% reduction in bone …

Progressive Changes In Microglia And Macrophages In Spinal Cord And Peripheral Nerve In The Transgenic Rat Model Of Amyotrophic Lateral Sclerosis, David J. Graber, William F. Hickey, Brent T. Harris

Dartmouth Scholarship

The role of neuroinflammation in motor neuron death of amyotrophic lateral sclerosis (ALS) is unclear. The human mutant superoxide dismutase-1 (hmSOD1)-expressing murine transgenic model of ALS has provided some insight into changes in microglia activity during disease progression. The purpose of this study was to gain further knowledge by characterizing the immunological changes during disease progression in the spinal cord and peripheral nerve using the more recently developed hmSOD1 rat transgenic model of ALS. Using immunohistochemistry, the extent and intensity of tissue CD11b expression in spinal cord, lumbar nerve roots, and sciatic nerve were evaluated in hmSOD1 rats that were …

Il-9 As A Mediator Of Th17-Driven Inflammatory Disease, Elizabeth C. Nowak, Casey T. Weaver, Henrietta Turner, Sakhina Begum-Haque, Burkhard Becher, Bettina Schreiner, Anthony J. Coyle, Lloyd H. Kasper, Randolph J. Noelle

Dartmouth Scholarship

We report that like other T cells cultured in the presence of transforming growth factor (TGF) beta, Th17 cells also produce interleukin (IL) 9. Th17 cells generated in vitro with IL-6 and TGF-beta as well as purified ex vivo Th17 cells both produced IL-9. To determine if IL-9 has functional consequences in Th17-mediated inflammatory disease, we evaluated the role of IL-9 in the development and progression of experimental autoimmune encephalomyelitis, a mouse model of multiple sclerosis. The data show that IL-9 neutralization and IL-9 receptor deficiency attenuates disease, and this correlates with decreases in Th17 cells and IL-6-producing macrophages in …

Phenotypic Alterations In Type Ii Alveolar Epithelial Cells In Cd4+ T Cell Mediated Lung Inflammation, Marcus Gereke, Lothar Gröbe, Silvia Prettin, Michael Kasper, Stefanie Deppenmeier, Achim D. Gruber, Richard I. Enelow, Jan Buer, Dunja Bruder

Dartmouth Scholarship

Although the contribution of alveolar type II epithelial cell (AEC II) activities in various aspects of respiratory immune regulation has become increasingly appreciated, our understanding of the contribution of AEC II transcriptosome in immunopathologic lung injury remains poorly understood. We have previously established a mouse model for chronic T cell-mediated pulmonary inflammation in which influenza hemagglutinin (HA) is expressed as a transgene in AEC II, in mice expressing a transgenic T cell receptor specific for a class II-restricted epitope of HA. Pulmonary inflammation in these mice occurs as a result of CD4+ T cell recognition of alveolar antigen. This model …

The Nestin Progenitor Lineage Is The Compartment Of Origin For Pancreatic Intraepithelial Neoplasia, Catherine Carriere, Elliot S. Seeley, Tobias Goetze, Daniel S. Longnecker, Murray Korc

Dartmouth Scholarship

To determine the cell compartment in which initial oncogenic mutations occur in pancreatic ductal adenocarcinoma (PDAC), we generated a mouse model in which endogenous expression of mutated Kras (Kras(G12D)) was initially directed to a population of pancreatic exocrine progenitors characterized by the expression of Nestin. Targeting of oncogenic Kras to such a restricted cell compartment was sufficient for the formation of pancreatic intraepithelial neoplasias (PanINs), putative precursors to PDAC. PanINs appeared with the same grade and frequency as observed when Kras(G12D) was targeted to the whole pancreas by a Pdx1-driven Cre recombinase strategy. Thus, the Nestin cell lineage is highly …

Transgenic Cyclin E Triggers Dysplasia And Multiple Pulmonary Adenocarcinomas, Yan Ma, Steven Fiering, Candice Black, Xi Liu, Ziqiang Yuan, Vincent A. Memoli, David J. Robbins, Heather A. Bentley, Gregory J. Tsongalis, Eugene Demidenko, Sarah J. Freemantle, Ethan Dmitrovsky

Dartmouth Scholarship

Cyclin E is a critical G(1)-S cell cycle regulator aberrantly expressed in bronchial premalignancy and lung cancer. Cyclin E expression negatively affects lung cancer prognosis. Its role in lung carcinogenesis was explored. Retroviral cyclin E transduction promoted pulmonary epithelial cell growth, and small interfering RNA targeting of cyclin E repressed this growth. Murine transgenic lines were engineered to mimic aberrant cyclin E expression in the lung. Wild-type and proteasome degradation-resistant human cyclin E transgenic lines were independently driven by the human surfactant C (SP-C) promoter. Chromosome instability (CIN), pulmonary dysplasia, sonic hedgehog (Shh) pathway activation, adenocarcinomas, and metastases occurred. Notably, …

Staphylococcus Aureus Agr And Sara Functions Are Required For Invasive Infection But Not Inflammatory Responses In The Lung, Geoffrey Heyer, Shahryar Saba, Robert Adamo, William Rush, Grace Soong, Ambrose Cheung, Alice Prince

Dartmouth Scholarship

Staphylococcus aureus strains lacking agr- and sarA-dependent gene products or specific MSCRAMM (microbial surface components recognizing adhesive matrix molecules) adhesins were compared for the ability to activate inflammatory responses in the lung. The mutants were evaluated for virulence in a mouse model of pneumonia and by quantifying their ability to stimulate interleukin-8 (IL-8) and granulocyte-macrophage colony-stimulating factor (GM-CSF) expression in respiratory epithelial cells. In a neonatal mouse, only strains with intact agr and sarA loci were consistently associated with invasive, fatal pulmonary infection (P < 0.001) and sarA was specifically required to cause bacteremia (P < 0.001). The agr and/or sarA mutants were, nonetheless, fully capable of producing pneumonia and were as proficient as the wild-type strain in stimulating epithelial IL-8 expression, a polymorphonuclear leukocyte chemokine, in airway cells. In contrast, agr and especially sarA mutants induced less epithelial GM-CSF expression, and MSCRAMM mutants lacking fibronectin binding proteins or clumping factor A, a ligand for fibrinogen, were unable to stimulate epithelial GM-CSF production. The ability to induce IL-8 expression was independent of the adherence properties of intact bacteria, indicating that shed and/or secreted bacterial components activate epithelial responses. While conserved staphylococcal components such as peptidoglycan are sufficient to evoke inflammation and cause pneumonia, the agr and sarA loci of S. aureus are critical for the coordination of invasive infection of the lungs.