The Center for Rare and Neglected Diseases

The Clinical-Translational Seminar Series -Dr. Padmini Salgame

(Above, from the left) November 30, 2012. Drs. Padmini Salgame. Patricia Champion, and Shahir Rizk enjoy a moment on the quad following Dr. Salgame's seminar at Geddes Hall.

On her recent visit to the University of Notre Dame's Center for Rare and Neglected Diseases, Professor Padmini Salgame addressed students and faculty on the topic of "Intrinsic and Extrinsic Factors Regulating Host Anti-tuberculosis Defense." Dr. Salgame's seminar focused on two central stories. The first part of her lecture disclosed her lab's examination of both innate and acquired immune responses to Mycobacterium tuberculosis (MTB) and the role of T-regulatory cells. Salgame highlighted some of what is and is not known about the functioning of the tuberculosis granuloma, memory T-cells, and biosignatures associated with individual adaptive immune responses and the susceptibility to infection.

The second part of Salgame's talk looked at research on co-infections of MTB and helminthic parasites. Salgame described her investigation into the pathogenesis of both diseases in co-infection, particularly how the effects of the immune responses related to one infection effects the progression of infection in the other disease. For example, helminthic infection raises Th2 cell responses. and those in turn, have the effect of down regulating the Th1 responses that are so critical in resisting MTB infections. The timing of infections is crucial to determining the interplay between the body's immune responses to the two diseases. TB has a high prevalence in many regions where helminthic diseases are endemic, and it is critical to discover how these co-infections modulate the course and outcome of MTB infections. Salgame's current examinations of helminth infections and the actions of immune responses in impeding MTB progression, together with her work in innate and acquired immunity, are providing significant insights that will aid in the the development of vaccines and treatments for TB.

Following her seminar, the gracious Director of Graduate Medical Research for the University of Medicine and Dentistry of New Jersey warmly welcomed graduate students in Drs. Champion and Lee's class for lunch and a relaxed discussion on a variety of topics (see photo below of the students with Dr. Salgame).

(Below, from the left) Graduate students from Drs. Champion and Lee's Topics in Pathobiology class - from the left, Rachel Schluttenhofer, Emily Williams, George Kennedy, Jennifer Zupkosky, Victoria Smith, Dr. Salgame, Jerome Fru Cho. (Photos: C Stackowicz, 2012)

Crislyn D'Souza-Schorey Is Named An AAAS Fellow

Professor Crislyn D'Souza-Schorey has been named a Fellow of the American Association for the Advancement of Science and cited for her “distinguished contributions to the field of cancer cell biology, particularly for studies on membrane traffic and ARF proteins in cell motility and tumor invasion.” The goal of D'Souza-Schorey's work is to discover information on the pathogenesis of cancer, which will ultimately serve in the development of novel diagnostic and therapeutic strategies for cancer treatment.

Warmest congratulations to Dr. D'Souza-Schorey on the occassion of this recognition of her work!

The Clinical-Translational Seminar Series -Dr. Vernon Carruthers

November 16, 2012. CRND's Director, Kasturi Haldar introduced Dr. Vernon Carruthers as "someone who knows more about the biology of cells and parasitic invasion than anyone I can think of." High praise considering that Drs. Carruthers and Haldar both share decades long careers investigating the mechanisms of parasitical infections. Carruthers and Haldar also enjoy alumnus status from The Rockefellar University, where they completed their postdoctoral work in Dr. George A.M. Cross's Laboratory of Molecular Parasitology. Carruthers was there in the early 1990's and Haldar completed in the late 1980s. Since then, each has pursued the study of the pathogenesis of a disease caused by a parasite. Carruther's identifies his protozoan parasite Toxoplasma gondii as "a cousin of the malaria parasite", which has been the focus of Haldar's investigations for many years. Both parasites are responsible for billions of infections annually, although Toxoplasma gondii creates a serious disease condition in only tiny percent of the 2 billion people who contract the infection. Generally, adults with healthy immune status manage to keep the parasite in an encysted state in the body and most of the people who become seriously ill from Toxoplasma gondii are infants or people who are immunocompromised due to another condition (e.g., HIV, organ transplant recipients, or chemotherapy patients).

Dr. Carruthers is currently a Professor in the Department of Microbiology and Immunology at the University of Michigan Medical School where his lab is focused on the study of Toxoplasma gondii as a "model" pathogen. A model pathogen is an organism that is extensively researched with the hope that discoveries about its biological functioning may also be extrapolated to understand the workings of similar organisms. According to Carruthers, the Toxoplasma gondii model works as a model for intracellular paracitism "because of its genetic and biochemical tractability, well defined cellular structure, and the availability of excellent rodent models of disease" (Carruthers Lab page).

Carruther's seminar was entitled, "Infection strategies of the highly successful neurotrophic parasite Toxoplasma gondii."

The Clinical-Translational Seminar Series -Dr. Timothy Grese

(Above, ND graduate student Stefan Freed and Dr. Timothy Grese)

The Clinical-Translational Seminar Series -Dr. George Dimopoulos

"Basically, no one had published on the circadian biology of the mosquito for a very long time. Finally, Dr. Dimopolous published his paper on photic inhibition of blood-feeding in Anapheles gambiae. This paper was crucial to my own research. Dr. Dimopoulos' work and generous advice to me over the years was really valuable to my project and eventual publication with Dr. Duffield."

-- Sam Rund, Ph.D. Cand. in Biology at Notre Dame

(Above: George Dimopoulos and Samuel Rund . Photo: C. Stackowicz, 2012)

October 26, 2012. Dr. George Dimopoulos presented his cutting-edge seminar for CRND to a delighted gathering of faculty and students whose research is focused in infectious diseases and global health. Dr. Dimopoulos's discoveries in vector control at Johns Hopkins Malaria Research Institute are very exciting because of their potential to use the mosquito's own immune system and gut microflora as means of attenuating its transmission of deadly diseases, namely malaria and dengue fever.

Dr. Dimopoulos began with maps. The first illustrated the gradual contraction of malaria endemic areas around the world. Dimopoulos pointed out the key role targeting the vector had played in elimination over 100 years. In the second illustration, Dimopoulos described the emerging growth pattern of dengue fever. According to Dimopoulos, his group works on understanding the processes of infection and immune response to both diseases, in projects that are distinct, but synergistically related. The synergy arises in the broadening of the overall knowledge about the biological processes comprising the mosquito's defense against pathogens, the understanding its genetic structures, and the development of specialized tools that serve a variety of purposes.

Dimopoulos' lab has made significant progress utilizing advanced gene expression analysis methods and technology to analyze the mosquito's functional genomics and characterize pathways, which regulate immune response and resistance to infection. In fact, the Dimopoulos group's project page reports "the first full genome microarrays for Anopheles gambiae, Aedes aegypti, Culex pipiens and Plasmodium berghei" were developed by his lab.

Dimopoulos' discussion of the role of mosquito's own innate immune system, which has evolved to protect it from the malaria parasites it ingests while feeding, summarized a number of experiments leading to the characterization of the "Imd pathway." This pathway plays a crucial role in mediating the mosquito's biological ability to fight off infection. The Dimopoulos Lab's success in describing the progressive immunological responses of the mosquito at the level specific genetic transcriptions is a powerful advance towards gene-based interventions. These interventions will eventually assist the mosquito in resisting infection and consequently reduce it's transmission of the disease to humans. Dimopoulos is careful to underline that the current approach his research aims at is a kind of genetic jumpstart of an existing immune response against the infection based on the mosquito's innate characteristics. The idea, according to Dimopoulos, is to "make the gene turn on earlier" in the infection response and to "not introduce something new."

A key finding of the Dimopoulos group is that specific microflora in the mosquito's gut are critical to its defense against parasitic invasion and the production of sporozoites. It is these sporozoites that infect the salivary glands of the insect and eventually find their way into new hosts when the mosquito feeds.

Visit the Dimopoulos groups project page to read about their advances in vector control research, many of which were described by Dr. Dimopoulos in his brilliantly accessible presentation. Indeed, a number of international students and researchers commented with pleasure on how easy it was to follow Dimopoulos's comprehensive and detailed exposition. In the words of Leonardo DaVinci: “Simplicity is the ultimate sophistication.”

George Dimopoulos, Ph.D., M.B.A. is a Professor in the Department of Molecular Microbiology and Immunology at Johns Hopkins University. He is also the Director of the Parasitology Core Facility and Deputy Director of the Malaria Research Institute, which are part of Hopkins' Bloomberg School of Public Health.

- Building Discovery In Vector Control -

Rund SS, Hou TY, Ward SM, Collins FH, and Duffield GE. (2011). Genome-wide profiling of diel and circadian gene expression in the malaria vector Anopheles gambiae. Proc Natl Acad Sci USA. 2011 Aug9; 108(32):E421-30.

Das, S., and Dimopolous G. (2008). Molecular analysis of photic inhibition of blood-feeding in Anopheles gambiae. BMC Physiology 16; 8(1):23.

Md. Suhail Alam et al. publish in PLoS One on NPC Biomarkers- 10/19/12

(Left, Dr. Suhail Alam. Photo, Rizk, 2012)

Dr. Md. Suhail Alam, together with researchers from the Center for Rare and Neglected Diseases/ Haldar Lab and the Indiana University School of Medicine – South Bend, has published the first study to identify 12 genes in the brains of NPC mice, whose protein expressions have the potential to function as plasma markers for lysosomal storage disorders, including Neimann Pick Type C. The identification of these potential markers promises to assist in the development of diagnostics for early blood-based detection of lysosomal storage diseases. The study also shows that a type of immune cell, called a neutrophil, builds up abnormally in the liver and spleen of NPC mice. This occurrence was not previously suspected as a factor in NPC (or related disorders), but may worsen disease progression, especially in the liver.

Niemann-Pick type C disease (NPC) is a rare genetic disorder, which results from the inheritance of defective copies of either of the Npc1 or the Npc2 gene. NPC is a lysosomal storage disorder characterized by the accumulation of cholesterol and glycolipids in lysosomes of cells in the body. Lysosomes function inside cells to digest materials taken in from the outside and to clear degraded materials following internal processing. In NPC, this process is disrupted as the protein products of the defective NPC genes fail to transport lipids across the lysosmes. The accumulation of these lipids in the lysosomal compartments effects the brain, liver and spleen, resulting in severe neurological dysfunction, morbidity and mortality.

The study by Alam et al., sought to identify factors associated with NPC disease severity stages (asypmptomatic, early-, and late-) using genome-wide gene expression analysis in the sentinel (disease indicating) organs associated with the disease: brain, liver, and spleen. The researchers found a noticeable increase in the gene expressions related to a dozen genes primarily related to innate immunity, with the expression steadily increased with age in the brain, liver, and spleen. The elevation of neutrophil in NPC mice was also found to be associated with tissue damage in the liver and spleen.

The diagnosis of NPC, as well as other lysosomal storage disorders, has often been delayed because of the lack of simple blood tests for the diseases. In this study, the identification of genetic biomarkers (proteins produced as a result of genetic encoding) further illuminates the biochemical processes of the disease and its stages. The identification of these biochemical markers may make it possible to determine the presence of the disease through a relatively simple blood test in the future. Early diagnosis of NPC and lysosomal disorders is linked to earlier treatment and better outcomes for patients.

To read the paper in PLoS ONE (open access)...

(Left) The paper's second author, Ms. Michelle Getz, research technician for the Haldar Lab, contributed her expert skills and understanding of the mouse model and labratory methods to achieve critical portions of the experimentation. (Photo, Rizk, 2012)

Genomic Expression Analyses Reveal Lysosomal, Innate Immunity Proteins, as Disease Correlates in Murine Models of a Lysosomal Storage Disorder. Md. Suhail Alam 1,2, Michelle Getz 1,2, Innocent Safeukui 1,2, Sue Yi 1,2, Pamela Tamez 1,2, Jenny Shin 1,2 , Peter Velázquez 1,3 , Kasturi Haldar 1,2* (2012) PLoS ONE 7(10): e48273. doi:10.1371/journal.pone.0048273

The Clinical-Translational Seminar Series -Dr. Dara Frank

(Above) Dr. Dara Frank met with graduate students in the Clinical Translational Seminar and Readings in Pathology Course. From the left, Jeannie Hoang, George Kennedy, Victoria Smith, Professor Frannk, Rachel Schluttenhofer, Emily Williams. (Photo: C Stackowicz, 2012)

On October 12, 2012, Dr. Dara Frank visited the CRND and delivered a fascinating lecture on her lab's penetration of the opportunistic strategies of a pathogen, which is responsible for significant morbidity and mortality in humans and animals. Dr. Frank's seminar, "Molecular and Cellular Analyses of the Pseudomonas aeruginosa Cytotoxin, ExoU" further illuminated the work she described a 2011 paper outlining her team's discovery of the role of Ubiquitin in the toxic effects of P. aeruginosa (Anderson et al., Molecular Microbiology 82(6) 1454-1467). Graduate students of Drs. Patricia Champion and Shaun Lee had read Frank's paper in preparation for the study's principal investigator's visit. Dr. Frank is a Professor of Microbiology and Molecular Genetics at the Medical College of Wisconsin and the Director, Center for Infectious Disease Research.

Dr. Frank's research is focused on the interaction between hosts and bacterial factors involved in infections with Pseudomonas aeruginosa and Francisella tularensis. She explores the genetic regulation of exotoxin synthesis, examining the relationship between the expression of toxins (e.g., toxins injected into eukaryotic cells that compromise the innate immunity in hosts), the pathogenesis of the bacterium, and host responses.

In her seminar, Dr. Frank described the process by which the common bacterium, P. aeruginosa, carries the effector protein, ExoU, in an inactivated state where it cannot harm the bacterium. Once the bacterium infects a host cell, however, a protein in the host, Ubiquitin, activates ExoU and allows it to degrade the membrane of the host's eukaryotic cells. Commenting on Dr. Frank's seminar, Dr. Shahir Rizk praised her "very elegant experiment" for demonstrating that the host protein is indeed required for the toxic effect of this dangerous bacterial protein to take effect.

Pseudomonas aeruginosa is an opportunistic pathogen found in skin flora, as well as soil, water, and a variety of human environments. In humans and animals with compromised immunity, the bacterium may gain entry and colonize body organs with potentially fatal consequences. In medical facilities, the bacterium may be found in medical equipment or implements and have disastrous results, particularly in the case of biofilms of P. aeruginosa, which are particularly resistant to treatment with antibiotics.

Dr. Frank's lab played a leading role in the discovery and characterization of the "P. aeruginosa type III system," which mediates the delivery of toxins. Her lab continues to explore enzyme inhibitors, antibody reagents, and vaccines, which may potentially neutralize these damaging toxins.

The New Fall 2012 Issue of the Signal - CRND 's Newsletter

The Clinical-Translational Seminar Series - Dr. Carole Long -

October 5, 2012. Dr. Long's seminar to CRND faculty and students entitled, "Progress toward development of a malaria vaccine" provided a comprehensive overview of the current status of vaccine development for various stages of malaria infection. Her presentation reviewed considerations for evaluating new vaccine targets and engaged the audience in an intriguing reflection on what is already known about the acquisition of immunity in endemic areas.

Dr. Long applauded the recent progress in vaccine development due to an expansion of funding and new technologies that have accelerated research. Dr. Long cited the significant advance represented in 2011 with the publication of "First results of phase 3 trial of RTS,S/AS01 malaria vaccine in African children" by Agnandji et al. (NEJM 365(20); 1863). This publication by a group from the Albert Schweitzer Hospital in Lambarene, Gabon, reports on an ongoing phase 3 study of over 15,000 children in seven African countries with respect to the malaria vaccine RTS,S/AS01. Dr. Long is the director of the PATH Malaria Vaccine Initiative, which together with GlaxoSmithKline Biologicals, is funding this research. Agnandji et al. conclude in their NEJM article: "The RTS,S/AS01 vaccine provided protection against both clinical and severe malaria in African children."

Following her presentation, Dr. Long joined ND graduate students for lunch and a lively informal discussion of her research and the extraordinary scope and achievement of the PATH Malaria Vaccine initiative.

The Clinical-Translational Seminar Series - Dr. Jose Bufill-

September 21, 2012 - Dr. Jose Bufill's contribution to the CRND Clinical-Translational Semininar Series, "Preliminary observations using N-acetylcysteine for refractory TTP: An opportunity for new management strategies?" engaged both students and faculty in an exciting translational discovery underway in their own community. Dr. Bufill has been treating a patient in South Bend with refractory, relapsing thrombotic thrombocytopenic purpura (TTP), a rare disorder of the blood-coagulation system. Using N-acetylcysteine (NAC), Dr. Bufill has observed noteworthy temporary therapeutic benefits without significant side effects.

Dr. Bufill's presentation described the pathophysiology of TTP, a serious and life-threatening disorder caused by dysfunction of the normal metabolism of the Von Willibrand factor (VWF). According to the National Heart, Lung, and Blood Institute: "In TTP, blood clots form in small blood vessels throughout the body. The clots can limit or block the flow of oxygen-rich blood to the body's organs, such as the brain, kidneys, and heart. As a result, serious health problems can develop." (To read more from the NHLBI website).

TTP may be either a congenital or inherited condition and is prone to relapse since the standard therapy of plasma exchange does not remedy the underlying cause. Recently, N-acetylcysteine (NAC) has shown promise in animal models. Dr. Bufill discussed further laboratory and clinical studies projected for NAC related compounds and their potential benefits for patients with this rare disorder.

Dr. Patricia Champion Publishes in Molecular and Cellular Proteomics

September 2012 - Dr. Shahir Rizk, CRND's Director of External Programs, recently spoke to UND's Dr. Patricia Champion about her new publication in Molecular & Cellular Proteomics. Dr. Rizk describes the core finding, "identifying key features of tuberculosis infection and the development of a new method for identifying important factors that tuberculosis bacteria use to infect human cells" in the upcoming CRND newsletter, The Signal. Seed funding was provided by a CRND proteomics grant. See the abstract for Champion's innovative study below. (Left, Dr. Patricia Champion)

"Direct Detection of Bacterial Protein Secretion Using Whole Colony Proteomics." Matthew M. Champion, Emily A. Williams, George M. Kennedy, and Patricia A. DiGiuseppe Champion. Molecular & Cellular Proteomics. First Published on May 10, 2012. OA publication: September 1, 2012 Molecular & Cellular Proteomics, 11, 596-604.

Abstract
Bacteria use a variety of secretion systems to transport proteins beyond their cell membrane to interact with their environment. For bacterial pathogens, these systems are key virulence determinants that transport bacterial proteins into host cells. Genetic screens to identify bacterial genes required for export have relied on enzymatic or fluorescent reporters fused to known substrates to monitor secretion. However, they cannot be used in analysis of all secretion systems, limiting the implementation across bacteria. Here, we introduce the first application of a modified form of whole colony MALDI-TOF MS to directly detect protein secretion from intact bacterial colonies. We show that this method is able to specifically monitor the ESX-1 system protein secretion system, a major virulence determinant in both mycobacterial and Gram-positive pathogens that is refractory to reporter analysis. We validate the use of this technology as a high throughput screening tool by identifying an ESAT-6 system 1-deficient mutant from a Mycobacterium marinum transposon insertion library. Furthermore, we also demonstrate detection of secreted proteins of the prevalent type III secretion system from the Gram-negative pathogen, Pseudomonas aeruginosa. This method will be broadly applicable to study other bacterial protein export systems and for the identification of compounds that inhibit bacterial protein secretion.

The Clinical-Translational Seminar Series- Dr. Patrick Duffy -

About The Inaugural CTSS Seminar

This fall, the CTSS seminar series was kicked off with an exciting presentation by Dr. Partick Duffy, discussing the recent progress in the fight against malaria. Dr. Duffy is a clinical researcher, whose work at the National Institutes of Health has taken him all around the world to malaria endemic areas where help is most needed. Often, such areas experience high levels of poverty and political turmoil. Most recently, Dr. Duffy found himself in the midst of a coup d’etat in Mali while training a group of students.

Dr. Duffy’s talk gave a taste of what’s to come. Several speakers are lined up throughout the semester with topics ranging from the study of infections by parasites, bacteria and viruses, to the characterization of the immune response to those infections, as well as the work carried out in developing novel therapeutic agents.

~ Dr. Shahir Rizk, Director of External Programs for the CRND

The Rare Health Exchange - RHE

The Rare Health Exchange (RHE) website is a web-based student collaboration to advance research, education, advocacy and patient support for the rare disease community. The RHE initiative has been supported from incubation to launch by a diverse group of sponsors including the Deans of the Colleges of Science and Engineering, the Office of the Vice-President of Research, the FISH non-profit organization, the Center for Social Concerns and the leadership of the CRND. Visit the Rare Health Exchange website.