Position(s):
Assistant Research Professor
Dept. of Biology

Office: 238 Stratton Hall
Lab: 210 Stratton Hall

Phone:  (215) 895-1435 (Office)
             (215) 895-1273 (Fax)

Email: Ritz@drexel.edu

B.S. - Pennsylvania State University
Ph.D. - Drexel University

Courses Taught

BIO 426  Introduction to Immunology
BIO 480/675  Advanced Immunology
NFS 215  Nutritional (Bio)Chemistry
NFS 217/404  Nutritional (Bio)Chemistry Lab

My research focuses on the interface between nutrition, age, and immunity.  Although aging is an inevitable part of life, we do not all age in the same way.  Some elderly men and women over the age of 65-70 maintain immune systems that resemble those of thirty-somethings, while others maintain little immune activity at all.  Nutrition is a key factor influencing immune status in the young and the old.  I study the role of nutrition on immune outcomes by altering nutritional status, such as by restricting calories or supplementing with nutraceutical compounds, and evaluating the immune response to influenza, a relevant virus infection.  Thus, this work has clear and practical public health implications.  I am particularly interested in innate immunity, which involves the action of specialized immune cells called natural killer cells, or NK cells.  NK cells are among the first responders of the immune system, and they are referred to as killers, because they rid the body of virus-infected or cancerous cells.  As the body’s first line of defense against a virus infection, NK cells set the stage for an effective immune response.  Our group has demonstrated the essential role of NK cells in controlling virus titers early in the immune response to influenza infection, and we have clearly demonstrated that nutritional interventions, such as immunomodulatory nutracetuicals, can affect NK cell activity and the innate immune response to acute infection.  Importantly, NK cell receptors are non-specific meaning that NK cell induction does not require antigen recognition and does not benefit from previous exposure.  Thus, NK cell function demonstrates exciting potential as a therapeutic target for enhancing the immune response to a broad spectrum of infectious threats.

Research topics:

Immunomodulatory nutraceuticals
Natural killer cells and the immune response to primary virus infection
Caloric restriction and susceptibility to primary influenza infection
Metabolism and innate immunity
Immunity in microgravity models of space flight

Selected publications:

Ritz BW, Aktan I, Nogusa S, Gardner EM. Energy restriction impairs natural killer cell function and increases the severity of influenza infection in young adult C57BL/6 male mice. J Nutr. 2008, in press.

Nogusa S, Ritz BW, Kassim SH, Jennings SR, Gardner EM. Characterization of age-related changes in natural killer cells during primary influenza infection in mice. Mech Age Devel. 2007, Mech Age Devel. 2008;129:223-30.

Kassim SH, Rajasagi NK, Ritz BW, Pruett S, Gardner EM, Chervenak R, Jennings SR. Dendritic cells are required for optimal activation of natural killer functions following primary infection with herpes simplex virus type-1 (HSV-1). J Immunol. 2008, submitted.

Ritz BW, Nogusa S, Ackerman EA, Gardner EM. Supplementation with Active Hexose Correlated Compound increases the innate immune response of young mice to primary Influenza Infection. J Nutr. 2006;136:2868-73.

Ritz BW and Gardner EM. Malnutrition and energy restriction differentially affect viral immunity. J Nutr. 2006;136(5):1141-4.

Ritz BW, Lelkes PI, Gardner EM. Functional recovery of peripheral blood mononuclear cells in modeled microgravity. FASEB J. 2006;20:303-7.

Duarte J, Vinderola CG, Ritz B, Perdigon G, Matar C. Immunomodulating capacity of commercial fish protein hydrolysate for diet supplementation. Immunobiology. 2006;211(4).

Organizations:

Federation of the American Society for Experimental Biology
American Society for Nutrition
Secretary, Nutritional Immunology-Research Interest Section

Graduate Students:

Shoko Nogusa- Characterizing intrinsic versus extrinsic age-associated defects in NK cell function using adoptive transfer and a novel assay for determining NK cell cytotoxicity in response to influenza infection in vivo

Eric B. Wong- Investigating phenotypic and functional characteristics of basal and inducible NK cell populations, including an evaluation of developmental changes in activating receptors