Nutrition and the Immune System:

Advances, Implications and a Case Study

Ebenezer Satyaraj, PhD, Nestle Purina Research Center

 

A healthy immune system is central to the overall health and longevity of your dog. The immune system has been traditionally considered in anatomical terms. However, to completely appreciate its role, it has to be defined in functional terms- not just a collection of cells, tissue and organs, but a finely orchestrated combination of biological systems and processes, designed to protect your dog. Interestingly, significant amount of immune cells reside in the lining of the gut in what is referred to as 'gut-associated lymphoid tissue'. As a result, the diets you feed your dog interact with a substantial part of his immune system, making nutrition an effective means of influencing the immune system. We will discuss Nestle Purina's strategy at targeting the immune system via nutrition and describe how an immune-enhancing ingredient is evaluated, tested and formulated into diet, as a case-study in 'Research to Retail'.

 

Biographical Profile

 

Dr. Ebenezer Satyaraj earned a Doctor of Philosophy in Immunology from the National Institute of Immunology, New Delhi, India in 1996. He continued his training at the University Of Chicago, Illinois, as a Postdoctoral Fellow in Department of Molecular Genetics & Cell Biology doing research in Molecular Immunology. Dr. Satyaraj then accepted a teaching position at the Department of Medicine, Northwestern University Medical School in Chicago where he taught Immunology and conducted research in the area of autoimmunity. In 2001 he joined Molecular Staging Inc. a biotech company working in the area of disease biomarkers where he coordinated research collaborations with the universities and pharmaceutical industry. Dr. Satyaraj has authored numerous scientific and technical publications, including a recent publication in the Journal Science that explains size variations in dogs. Dr. Satyaraj joined Purina in 2003 where he currently serves as Research Scientist in the Nestle Research Center conducting research in the area of nutritional immunology & cytokine biology. He and his family live in Wildwood, Missouri.

 

Nutrition and the Immune System – conference notes

 

Two key ideas

            A healthy immune system is central overall health and longevity

            The immune system can be effectively modulated by nutrition

 

What we learn through genomics needs to be applied to the whole animal.

 

The immune system consists of a collection of cells, tissues and organs, that is part of a finely orchestrated combination of biological systems and process that protect the integrity of the organism from internal and external threats.

            Innate arm – primary defense

            Adaptive arm – secondary defense through recognition, optimization and memory processes (vaccines, etc)

 

The gut is the largest is the immune organ – the majority of the immune cells are in your gut - which makes it easier to moderate immune responses.

 

Why enhance immune health of a healthy animal?

            Even in a healthy animal can have a deficient immune system.  The young and the old have an immune system will not at its optimum level.  Stress, fatigue and disease also alter immune system levels and thus responses.

 

Immunity gap in puppies

            -Puppies’ immune system takes several weeks to months to fully develop

            -Maternal antibodies from colostrum lasts for about 12 weeks

-Early vaccination are administered after 10-12 weeks to avoid interference from maternal antibodies

            -For the first 12 weeks of age your pup is primarily protected by maternal antibodies

-Maternal antibodies, however, may not be sufficient even if the pup is weaned appropriately

                        Insufficient antibodies produced by mom

                        Inadequate intake of colostrum

                        Insufficient absorption of antibodies by the pup

                        Movement of pup to different geographic area

Modulating immune system

            Genes and life stage are set and cannot be modulated, however lifestyle and diet can be modulated.  Knowing that the majority of the immune cells are in the gut, make it easier to modulate.

 

Nutrition = immunity

1^st stage – complete balanced nutrition

2^nd stage – optimizing macro & micronutrients (selenium, Vit E, Vit D, etc) this stage is passive – giving ingredients for a strong system

3^rd stage – Strengthening & training the immune system (the use of probiotics) this stage is active

4^th stage – Personalized Nutrition, i.e. a dog with a compromised immune system – modulate the immune response

 

Examples of modulating immunity through nutrition:

 

Target physiology

            Discovery phase – research of products and identify ingredients that are safe and healthy

Nutritional trials – design nutritional trials, confirm statistical power of studies

Formulate diet – alter current products or modulate new products

Whey proteins – do they work for dogs?

            Antimicrobial activity

            Anticancer activity

            They are an excellent source of cysteine and glutamine

                        Glutamine is preferred fuel for muscle and immune cells

                        Immune cells cannot synthesize glutamine

                        Exercise, stress can deplete glutamine making immune cells weak.

Nutritional trial

            48 alaskan sled dogs, 2-6 years of age

            4 diets

                        Control

                        Test diet with WPC-1, WPC-2, WPC-3

            Trial lasted four weeks

                        Pretest, all animals given control food

                        All animals given boosters

            Immune and gut health measurement

                        Immune analysis

                        Gut health mesurements – fecal measurements & analysis

            Weight and blood profiles

                        No change in weight or blood profiles

            *dogs fed wpc1 & wpc3 showed improved immune response and local immune status

The immune system in animals fed diets with whey proteins is not hyperactive, it is responding appropriately and responding to stress as needed.

 

Test stress immune response

            2 day rest

            Begin training again – and analyze the gut microflora through testing fecal samples

                        In the control group, there was a shift in microflora (only 50% similarity)

                        In the test groups, there was no significant change in microflora (~80% similarity)

                        Therefore protein whey produced a stable gut under stress