Medicine and Health Sciences Commons^™

Oligomerization, Conformational Stability And Thermal Unfolding Of Harpin, Hrpzpss And Its Hypersensitive Response-Inducing C-Terminal Fragment, C-214-Hrpzpss., Pradip K Tarafdar, Lakshmi Vasudev Vedantam, Rajeshwer S Sankhala, Pallinti Purushotham, Appa Rao Podile, Musti J Swamy

Department of Biochemistry and Molecular Biology Faculty Papers

HrpZ-a harpin from Pseudomonas syringae-is a highly thermostable protein that exhibits multifunctional abilities e.g., it elicits hypersensitive response (HR), enhances plant growth, acts as a virulence factor, and forms pores in plant plasma membranes as well as artificial membranes. However, the molecular mechanism of its biological activity and high thermal stability remained poorly understood. HR inducing abilities of non-overlapping short deletion mutants of harpins put further constraints on the ability to establish structure-activity relationships. We characterized HrpZPss from Pseudomonas syringae pv. syringae and its HR inducing C-terminal fragment with 214 amino acids (C-214-HrpZPss) using calorimetric, spectroscopic and microscopic approaches. Both …

Hormone-Induced Calcium Oscillations Depend On Cross-Coupling With Inositol 1,4,5-Trisphosphate Oscillations., Lawrence D Gaspers, Paula J Bartlett, Antonio Politi, Paul Burnett, Walson Metzger, Jane Johnston, Suresh K Joseph, Thomas Höfer, Andrew P Thomas

Department of Pathology, Anatomy, and Cell Biology Faculty Papers

Receptor-mediated oscillations in cytosolic Ca(2+) concentration ([Ca(2+)]i) could originate either directly from an autonomous Ca(2+) feedback oscillator at the inositol 1,4,5-trisphosphate (IP3) receptor or as a secondary consequence of IP3 oscillations driven by Ca(2+) feedback on IP3 metabolism. It is challenging to discriminate these alternatives, because IP3 fluctuations could drive Ca(2+) oscillations or could just be a secondary response to the [Ca(2+)]i spikes. To investigate this problem, we constructed a recombinant IP3 buffer using type-I IP3 receptor ligand-binding domain fused to GFP (GFP-LBD), which buffers IP3 in the physiological range. This IP3 buffer slows hormone-induced [IP3] dynamics without changing steady-state …

A Plausible Mechanism, Based Upon Short-Root Movement, For Regulating The Number Of Cortex Cell Layers In Roots., Shuang Wu, Chin-Mei Lee, Tomomi Hayashi, Simara Price, Fanchon Divol, Sophia Henry, Germain Pauluzzi, Christophe Perin, Kimberly L Gallagher

Department of Medical Laboratory Sciences & Biotechnology Faculty Papers

Formation of specialized cells and tissues at defined times and in specific positions is essential for the development of multicellular organisms. Often this developmental precision is achieved through intercellular signaling networks, which establish patterns of differential gene expression and ultimately the specification of distinct cell fates. Here we address the question of how the SHORT-ROOT (SHR) proteins from Arabidopsis thaliana (AtSHR), Brachypodium distachyon (BdSHR), and Oryza sativa (OsSHR1 and OsSHR2) function in patterning the root ground tissue. We find that all of the SHR proteins function as mobile signals in A. thaliana and all of the SHR homologs physically interact …

Ido2 In Immunomodulation And Autoimmune Disease., George C Prendergast, Richard Metz, Alexander J Muller, Lauren M F Merlo, Laura Mandik-Nayak

Department of Microbiology and Immunology Faculty Papers

IDO2 is a relative of IDO1 implicated in tryptophan catabolism and immune modulation but its specific contributions to normal physiology and pathophysiology are not known. Evolutionary genetic studies suggest that IDO2 has a unique function ancestral to IDO1. In mice, IDO2 gene deletion does not appreciably affect embryonic development or hematopoiesis, but it leads to defects in allergic or autoimmune responses and in the ability of IDO1 to influence the generation of T regulatory cells. Gene expression studies indicate that IDO2 is a basally and more narrowly expressed gene than IDO1 and that IDO2 is uniquely regulated by AhR, which …

Transcriptome Profiling Of Spinal Muscular Atrophy Motor Neurons Derived From Mouse Embryonic Stem Cells., Miho Maeda, Ashlee W Harris, Brewster F Kingham, Casey J Lumpkin, Lynn M Opdenaker, Suzanne M Mccahan, Wenlan Wang, Matthew E R Butchbach

Department of Pediatrics Faculty Papers

Proximal spinal muscular atrophy (SMA) is an early onset, autosomal recessive motor neuron disease caused by loss of or mutation in SMN1 (survival motor neuron 1). Despite understanding the genetic basis underlying this disease, it is still not known why motor neurons (MNs) are selectively affected by the loss of the ubiquitously expressed SMN protein. Using a mouse embryonic stem cell (mESC) model for severe SMA, the RNA transcript profiles (transcriptomes) between control and severe SMA (SMN2+/+;mSmn-/-) mESC-derived MNs were compared in this study using massively parallel RNA sequencing (RNA-Seq). The MN differentiation efficiencies between control and severe SMA mESCs …

Loss Of Miro1-Directed Mitochondrial Movement Results In A Novel Murine Model For Neuron Disease., Tammy T Nguyen, Sang S Oh, David Weaver, Agnieszka Lewandowska, Dane Maxfield, Max-Hinderk Schuler, Nathan K Smith, Jane Macfarlane, Gerald Saunders, Cheryl A Palmer, Valentina Debattisti, Takumi Koshiba, Stefan Pulst, Eva L Feldman, György Hajnóczky, Janet M Shaw

Department of Pathology, Anatomy, and Cell Biology Faculty Papers

Defective mitochondrial distribution in neurons is proposed to cause ATP depletion and calcium-buffering deficiencies that compromise cell function. However, it is unclear whether aberrant mitochondrial motility and distribution alone are sufficient to cause neurological disease. Calcium-binding mitochondrial Rho (Miro) GTPases attach mitochondria to motor proteins for anterograde and retrograde transport in neurons. Using two new KO mouse models, we demonstrate that Miro1 is essential for development of cranial motor nuclei required for respiratory control and maintenance of upper motor neurons required for ambulation. Neuron-specific loss of Miro1 causes depletion of mitochondria from corticospinal tract axons and progressive neurological deficits mirroring …

Impact Of Distinct Poxvirus Infections On The Specificities And Functionalities Of Cd4+ T Cell Responses., Nicholas A Siciliano, Adam R Hersperger, Aimee M Lacuanan, Ren-Huan Xu, John Sidney, Alessandro Sette, Luis J Sigal, Laurence C. Eisenlohr

Department of Microbiology and Immunology Faculty Papers

UNLABELLED: The factors that determine CD4+ T cell (TCD4+) specificities, functional capacity, and memory persistence in response to complex pathogens remain unclear. We explored these parameters in the C57BL/6 mouse through comparison of two highly related (>92% homology) poxviruses: ectromelia virus (ECTV), a natural mouse pathogen, and vaccinia virus (VACV), a heterologous virus that nevertheless elicits potent immune responses. In addition to elucidating several previously unidentified major histocompatibility complex class II (MHC-II)-restricted epitopes, we observed many qualitative and quantitative differences between the TCD4+ repertoires, including responses not elicited by VACV despite complete sequence conservation. In addition, we observed functional …

Epithelial Immunization Induces Polyfunctional Cd8+ T Cells And Optimal Mousepox Protection., Adam R Hersperger, Nicholas A Siciliano, Brian C Dehaven, Adam E. Snook, Laurence C. Eisenlohr

Department of Microbiology and Immunology Faculty Papers

We assessed several routes of immunization with vaccinia virus (VACV) in protecting mice against ectromelia virus (ECTV). By a wide margin, skin scarification provided the greatest protection. Humoral immunity and resident-memory T cells notwithstanding, several approaches revealed that circulating, memory CD8(+) T cells primed via scarification were functionally superior and conferred enhanced virus control. Immunization via the epithelial route warrants further investigation, as it may also provide enhanced defense against other infectious agents.

Microrna Expression Differences In Human Hematopoietic Cell Lineages Enable Regulated Transgene Expression., Raúl Teruel Montoya, Xianguo Kong, Shaji Abraham, Lin Ma, Satya P Kunapuli, Michael Holinstat, Chad A Shaw, Steven E. Mckenzie, Leonard Edelstein, Paul Bray

Cardeza Foundation for Hematologic Research

Blood microRNA (miRNA) levels have been associated with and shown to participate in disease pathophysiology. However, the hematopoietic cell of origin of blood miRNAs and the individual blood cell miRNA profiles are poorly understood. We report the miRNA content of highly purified normal hematopoietic cells from the same individuals. Although T-cells, B-cells and granulocytes had the highest miRNA content per cell, erythrocytes contributed more cellular miRNA to the blood, followed by granulocytes and platelets. miRNA profiling revealed different patterns and different expression levels of miRNA specific for each lineage. miR-30c-5p was determined to be an appropriate reference normalizer for cross-cell …

The Regulator Of G Protein Signaling (Rgs) Domain Of G Protein-Coupled Receptor Kinase 5 (Grk5) Regulates Plasma Membrane Localization And Function., Hua Xu, Xiaoshan Jiang, Ke Shen, Christopher C. Fischer, Philip B Wedegaertner

Department of Biochemistry and Molecular Biology Faculty Papers

The G protein-coupled receptor (GPCR) kinases (GRKs) phosphorylate activated GPCRs at the plasma membrane (PM). Here GRK5/GRK4 chimeras and point mutations in GRK5 identify a short sequence within the regulator of G protein signaling (RGS) domain in GRK5 that is critical for GRK5 PM localization. This region of the RGS domain of GRK5 coincides with a region of GRK6 and GRK1 shown to form a hydrophobic dimeric interface (HDI) in crystal structures. Coimmunoprecipitation (coIP) and acceptor photobleaching fluorescence resonance energy transfer assays show that expressed GRK5 self-associates in cells, whereas GRK5-M165E/F166E (GRK5-EE), containing hydrophilic mutations in the HDI region of …

Succinate Dehydrogenase Deficiency In Sporadic Pituitary Adenomas: A Potential Mechanism For Tumorigenesis, Edward Andrews, Md, Stacey K. Mardekian, Md, Markku Miettinen, Mark T. Curtis, Md

Department of Pathology, Anatomy, and Cell Biology Resident's Posters

In order to determine whether succinate dehydrogenase (SDH) deficiency plays a role in spor-adic, non-familial pituitary adenomas, we analyzed 80 pituitary adenomas for SDH deficiency from patients without familial tumor syndromes or without known SDH deficiency-associated neoplasms. SDH deficiency was determined by immunohistochemical (IHC) stains for SDHB since the loss of any of the four SDH subunits results in the loss of SDHB expression. Three pituitary adenomas showed complete loss of SDHB staining, and of these two also showed loss of SDHA staining. We further characterized these adenomas by looking at Ki67, IGF1R, and 5-hmC levels via IHC. SDHx …

Comparison Of Two Quantitative Image Analysis Systems For Breast Cancer Immunohistochemistry, Reid H. Phillips, Bs, Sue Direnzo, Bs, Charalambos C. Solomides, Md

Department of Pathology Honors Program Student Research Symposium

Automated image analysis systems for breast cancer immunohistochemistry promise efficiency and reliability in the quantification of therapy targets such as the estrogen receptor (ER) or human epidermal growth factor receptor (Her2). Thomas Jefferson University Hospital owns two such systems, the Aperio ScanScope AT (Leica Biosystems) and Ventana iScan Coreo (Roche). A comparison study was performed to determine if choice of system affects target quantification and subsequent clinical tumor classification. Tumor expressions of ER, progesterone receptor (PR), proliferation marker Ki67, and Her2 were quantified with both systems for tissue samples from twenty breast cancer patients. Positive tumor classification was based on …

Evaluating The Utility Of Thyroglobulin Wash Testing In The Management Of Well-Differentiated Thyroid Carcinoma, Katelyn M. Seither, Rossitza Draganova-Tacheva, Md

Department of Pathology Honors Program Student Research Symposium

Introduction

• Thyroid cancer is the most common endocrine neoplasm worldwide, representing 1.7% of new cancer diagnoses and 0.5% of cancer deaths each year (Baldini et al.)
• The majority of thyroid cancers are primary (originating within the gland itself), are well-differentiated, and are derived from follicular epithelial cells
• Papillary thyroid cancer is the most common subtype

70-80% of all thyroid cancers

Peak incidence in women of child-bearing age

Generally indolent behavior, excellent prognosis with total thyroidectomy

30-90% of patients exhibit recurrent or persistent metastasis to the cervical lymph nodes (Torres et al.) and 20% of cases present with occult cancer that …

20 Year-Old Male With Destructive Lesion Of Orbital Roof, Paris A. Barkan, Bs, Lawrence C. Kenyon, Md, Phd

Department of Pathology Honors Program Student Research Symposium

Patient History

Mr. G.R. is a 20-year-old man with no significant past medical history. He presented in July of 2013 with two months of worsening pain over the right orbit. Periorbital edema was also present. Initial treatment with eye drops, antibiotics (erythromycin followed by cephalexin), and steroids (prednisone) failed to control his symptoms.

In October of 2013, CT and MRI scans revealed a permeative destructive lesion centered in the right orbital roof with extension into the superior orbit and the floor of the anterior cranial fossa. There was no abnormal enhancement in the visualized brain parenchyma.

The radiologic appearance of …

Mechanisms That Modify Immune Response In Neonatal Alloimmune Thrombocytopenia, Robert Cooper, Jay H. Herman

Department of Pathology Honors Program Student Research Symposium

What is NAIT?

Neonatal alloimmune thrombocytopenia (NAIT) is a form of fetal and neonatal thrombocytopenia caused by maternal-fetal platelet antigen incompatibility that results in placental transfer of maternal IgG alloantibodies against the platelet antigen. Currently, there are 28 human platelet antigen systems (HPA) that are polymorphisms of various membrane glycoprotein (GP) integrins. The first HPA and most immunogenic was discovered in the 1960’s and is now termed HPA-1, a diallelic system with HPA-1a and HPA-1b on the GPβ3 subunit of the fibrinogen receptor (Murphy). Approximate HPA-1 phenotype frequencies are: homozygous 1a,1a (~70%); heterozygous 1a,1b (~28%); homozygous 1b,1b (~2%).

Typically an …

Hiv Associated Neurocognitive Disorders In An Antiretroviral Therapy Era, Molly Halloran, David S. Strayer, Md, Phd

Department of Pathology Honors Program Student Research Symposium

HIV emerged as a major threat to world health over 30 years ago, and while its effects on the immune system are widely known, HIV also has broad and devastating effects on the nervous system. Despite our potent antiretroviral therapies (ART), these HIV-associated neurocognitive disorders (HAND) continue to afflict HIV infected individuals. With over 33 million people infected worldwide and evidence that neurological damage can accrue in virologically well controlled individuals, HAND is a pressing challenge. Nevertheless, many questions remain unanswered about this spectrum of disorders.

Peripheral T-Cell Lymphoma Arising From Age-Related Ebv-Associated Lymphoproliferative Disorder (Ar-Ebvlpd), Alaina Chodoff, Msii, Guldeep Uppal, Md, Jerald Z. Gong, Md

Department of Pathology Honors Program Student Research Symposium

In the setting of underlying immune suppression, Epstein Barr Virus (EBV) is a well-recognized oncogenic agent that induces the malignant proliferation of B-cells. EBV-lymphoproliferative disorders (LPDs) have recently been linked to immunosenescence. We present a unique case of Age-Related EBV-Lymphoproliferative Disorder (AR-EBVLPD) in a 70 year old female that deviates from the characteristic progression of this disease. Over the course of 18 months, the patient’s clinical condition worsened without a definitive diagnosis to explain the severe, atypical widespread chronic inflammation spanning her gastrointestinal tract, from esophagus to small bowel. The diagnosis of AR-EBVLPD, polymorphic extranodal subtype, was delayed until the …

Haploidentical Hematopoietic Stem Cell Transplantation: Rationale, Development, And Jefferson’S Method, Susan Mcilvaine, Dolores Grosso, Rn, Crnp, Dnp, Beth Colombe

Department of Pathology Honors Program Student Research Symposium

INTRODUCTION

There are many indications for hematopoietic stem cell transplantation. In addition to hematologic malignancies, transplants are performed in certain non-hematologic malignancies, for marrow disorders such as Sickle Cell Anemia, and for various inherited disorders such as SCID. Traditionally, transplants have been performed between donors and recipients that are a complete HLA match (typically matched siblings). That is, patients have identical HLA alleles on both copies of chromosome 6. HLA alleles code for major histocompatibility complex molecules, which are the proteins that cause transplant rejection when a mismatch between donor and recipient is present. Thus, matched transplants have been historically …

Amino Acid-Dependent Stability Of The Acyl Linkage In Aminoacyl-Trna., Jacob R Peacock, Ryan R Walvoord, Angela Y Chang, Marisa C Kozlowski, Ya-Ming Hou

Department of Biochemistry and Molecular Biology Faculty Papers

Aminoacyl-tRNAs are the biologically active substrates for peptide bond formation in protein synthesis. The stability of the acyl linkage in each aminoacyl-tRNA, formed through an ester bond that connects the amino acid carboxyl group with the tRNA terminal 3'-OH group, is thus important. While the ester linkage is the same for all aminoacyl-tRNAs, the stability of each is not well characterized, thus limiting insight into the fundamental process of peptide bond formation. Here, we show, by analysis of the half-lives of 12 of the 22 natural aminoacyl-tRNAs used in peptide bond formation, that the stability of the acyl linkage is …

The Intersection Between Hpv And Hiv Infections: Is There An Increased Susceptibility To Hiv Acquisition In Hpv-Infected Women?, Montida Fleming, Ba, Fred Gorstein, Md

Department of Pathology Honors Program Student Research Symposium

It has been well documented that HIV infection is associated with HPV infection and the progression to cervical carcinoma. Since the spread of HIV/AIDS epidemic, HPV-related cervical carcinoma had such a high prevalence in HIV-infected individuals that it became established as an AIDS-defining illness. Cervical cancer is the most common AIDS-related malignancy, and the sixth most common presenting AIDS-defining illness in women.¹ Additionally, HIV infection leads to a 5-fold increase in multiple new HPV infections within 6 weeks of seroconversion.² Not only does HIV impact acquisition of HPV at molecular and cellular levels, HIV and HPV viruses interact …

Lead Toxicity: What Is It And How Is It Happening?, Kimberly A. Parada, Ba, Jay S. Schneider, Phd

Department of Pathology Honors Program Student Research Symposium

EPIDEMIOLOGY

Lead poisoning accounts for 0.6% of the global burden of disease.

In Pennsylvania in 2010, 148,751 children under 72 months of age were tested for blood lead levels. Of those children, 19,176 had blood lead levels greater than 5 μg/dl.

• A lower socioeconomic status increases the chances for lead exposure.
• Lead toxicity is an under-appreciated problem that is entirely preventable.

Molecular Profiling Of Patients With Non Small Cell Lung Cancer At Jefferson University Hospital, Erin Bange, Renu Bajaj, Ms, Phd, Cg (Ascp), Cm, Facmg

Department of Pathology Honors Program Student Research Symposium

Companion diagnostics is the use of specific tests whose results are linked to a particular drug. It allows clinicians the ability to better target the mechanism of pathology in the patient and follow it up with a therapy specifically designed to treat the disease process at hand. This approach to medicine has particularly been championed in the field of oncology with the development of such drugs as Zelboraf for the treatment of metastatic melanoma with the BRAFV600 mutation or Xalkori for late stage lung cancer expressing an abnormal ALK protein. In the case of non-small cell lung cancer (NSCLC) Jefferson …

Plasmapheresis And Hiv-Associated Thrombotic Microangiopathy: An Institutional Review, Megan Fisher, Ms2, Nancy Edger Hall, Rn, Mba, Jennifer Webb, Md, Julie Karp, Md

Department of Pathology Honors Program Student Research Symposium

Thrombotic thrombocytopenic purpura (TTP) is a systemic disorder that classically results from a deficiency in the von Willebrand factor-cleaving enzyme, ADAMTS13. The human immunodeficiency virus (HIV) is a secondary cause of TTP. It has been recognized that some patients with HIV-associated TTP do not have a deficiency in ADAMTS13 activity. The role of plasmapheresis (PLEX) in these patients is unclear. This study reviewed 8 cases of HIV-associated TTP at Thomas Jefferson University Hospital. All patients responded to treatment; however, we were unable to make any conclusions regarding the use of PLEX in patients with normal ADAMTS13 activity. HAART initiation is …

Her-2 Heterogeneity In Breast Cancer: A Case Study, Kinnari Patel, Theodore Parsons

Department of Pathology Honors Program Student Research Symposium

CASE

The patient is a 75 year-old female with a history of stage 1 invasive ductal carcinoma of the left breast measuring 1.2 cm. Core biopsy of the mass demonstrated Nottingham grade 3 invasive ductal carcinoma; ER negative, PR negative, HER-2 negative (1+). The patient underwent mastectomy in April 2013. Mastectomy confirmed Nottingham grade 3 invasive ductal carcinoma pT1c/pN0/pMX with peritumoral lymphovascular invasion and invasive tumor less than 1 mm from the superoanterior margin. Due to comorbidities the patient was not considered a candidate for adjuvant chemotherapy.

In January 2014 the patient presented with a mastectomy site recurrence. Needle core …

Personalized Immune Therapy For Cancer A Potential Game-Changing Treatment, Emily Evron, Emanual Rubin, Md

Department of Pathology Honors Program Student Research Symposium

T-CELL RECEPTOR, NORMALLY

T-cell receptors reside on the surface of T-cells, and recognize a specific antigen presented by an MHC molecule

Next, the T-cells become either CD4 or CD8 cells

Co-stimulation is a key step in activating the T-cell; B7 proteins on the surface of antigen-presenting cells interact with CD28/CTLA-4 receptors on the T-cell.

Small Cell Carcinoma Of The Bladder: A Rare Entity, Andrew H. Matthews, Ruth Birbe, Md

Department of Pathology Honors Program Student Research Symposium

BACKGROUND

Primary small cell carcinoma of the urinary bladder is a rare tumor, accounting for less than 1% of the annual 70,000 cases of urinary bladder cancer.¹ Accordingly, little data is available beyond case series to guide diagnosis or treatment. Overall prognosis remains poor with five year survival often markedly below 50%. Current staging and treatment remains largely based on extrapolation from small cell carcinoma of the lung. We review two recent cases of bladder small cell carcinoma with a focus on comparing and contrasting with lung small carcinoma.

Giant Cell Tumor Of Soft Tissue: A Case Study, Rachel Schneider, Brian J. O'Hara

Department of Pathology Honors Program Student Research Symposium

BACKGROUND

Giant cell tumors of soft tissue are relatively uncommon tumors. They are considered to be the soft tissue counterpart to giant cell tumors of bone. Both tumors consist of multi-nucleated giant cells evenly distributed throughout a background of epithelioid mononuclear cells, and are usually benign, but can be locally invasive. Giant cell tumors of soft tissue typically occur in patients over age 40, and show no gender or racial predilection. They present as firm, well demarcated masses, which are not connected to the underlying muscle, tendon, or bone. Giant cell tumors of soft tissue are generally small, and tend …

Small Cell Carcinoma Of The Breast, Victor Carlson, Paolo Cotzia, Md, Juan P. Palazzo, Md

Department of Pathology Honors Program Student Research Symposium

INTRODUCTION

Small cell carcinoma of the breast (SCCB) is a rare, highly aggressive neoplasm first reported in 1983. With striking histologic similarity to small cell carcinoma of the lung, it is comprised of small cells with relatively large, hyperchromatic nuclei and scanty cytoplasm. While capable of hormone secretion, this is a rare occurrence in this variant of small cell carcinoma. Patients typically present with a suspicious breast mass confirmed on imaging, with variable lymph node invasion.

Importance Of Cbct Setup Verification For Optical-Guided Frameless Radiosurgery., Lei Fu, Harold Perera, Xiao Ying, Yan Yu

Department of Medical Genetics Faculty Papers

The purpose of this study is to quantify the discrepancy between optical guidance platform (OGP) frameless localization system (Varian) and Trilogy on-board imaging (OBI) system (Varian) for setting up phantom and stereotactic radiosurgery (SRS) patient; and to determine whether cone-beam CT (CBCT) is necessary for OGP patient setup, and compare CBCT and orthogonal kV-kV in term of their verification capability. Three different phantoms were used in the study: a custom-made phantom, a Penta-Guide phantom, and a RANDO phantom. Five patients using both OGP and CBCT setup and 14 patients using CBCT setup alone were analyzed. One patient who had big …

Interleukin-7-Dependent B Lymphocytes Are Required For The Anti-Pneumococcal Polysaccharide Response And Protective Immunity To Streptococcus Pneumoniae, Gregory S. Dickinson, Phd, Raja Vuyyuru, Timothy L. Manser, Phd, John F. Kerney, Kishore Alugupalli, Phd

Department of Microbiology and Immunology Faculty Papers

Unlike human adults or adult mice, young children or young mice respond poorly to pneumococcal polysaccharides (PPS). In mice, B1b lymphocytes are the major responders to a variety of bacterial polysaccharides including PPS. Despite having B1b cells, young mice are severely impaired in responding to PPS, suggesting that B cells in the young are distinct from those in adults. Since B lymphopoeisis early in life is largely Interleukin-7 (IL-7)-independent, while in adults it is IL-7-dependent, we hypothesize that B cells developed in the presence of IL-7 are required for generating anti-PPS antibody responses. In support of this, we found that …