NUTRITION AND IMMUNE FUNCTION potx

FRONTIERS IN NUTRITIONAL SCIENCE

This series of books addresses a wide range of topics in nutritional science. The

books are aimed at advanced undergraduate and graduate students,

researchers, university teachers, policy makers and nutrition and health profes￾sionals. They offer original syntheses of knowledge, providing a fresh perspec￾tive on key topics in nutritional science. Each title is written by a single author

or by groups of authors who are acknowledged experts in their field. Titles

include aspects of molecular, cellular and whole body nutrition and cover

humans and wild, captive and domesticated animals. Basic nutritional science,

clinical nutrition and public health nutrition are each addressed by titles in the

series.

Editor in Chief

P.C. Calder, University of Southampton, UK

Editorial Board

A. Bell, Cornell University, Ithaca, New York, USA

F. Kok, Wageningen University, The Netherlands

A. Lichtenstein, Tufts University, Massachusetts, USA

I. Ortigues-Marty, INRA, Thiex, France

P. Yaqoob, University of Reading, UK

K. Younger, Dublin Institute of Technology, Ireland

Titles available

1. Nutrition and Immune Function

Edited by P.C. Calder, C.J. Field and H.S. Gill

Nutrition00 4/9/02 4:03 PM Page i

Nutrition00 4/9/02 4:03 PM Page ii

NUTRITION AND IMMUNE

FUNCTION

Edited by

Philip C. Calder

University of Southampton, UK

Catherine J. Field

University of Alberta, Canada

and

Harsharnjit S. Gill

Massey University, New Zealand

CABI Publishing

in association with

The Nutrition Society

Nutrition00 4/9/02 4:03 PM Page iii

CABI Publishing is a division of CAB International

CABI Publishing CABI Publishing

CAB International 10 E 40th Street

Wallingford Suite 3203

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© CAB International 2002. All rights reserved. No part of this publication may

be reproduced in any form or by any means, electronically, mechanically, by

photocopying, recording or otherwise, without the prior permission of the copy￾right owners.

A catalogue record for this book is available from the British Library, London,

UK.

Library of Congress Cataloging-in-Publication Data

Nutrition and immune function / edited by Philip C. Calder.

p. cm. -- (Frontiers in nutritional science ; no. 1)

Includes bibliographical references and index.

ISBN 0-85199-583-7

1. Immune system. 2. Nutrition. 3. Natural immunity. 4. Dietary

supplements. I. Calder, Philip C. II. Series.

QR182 .N88 2002

616.079--dc21

2002004470

ISBN 0 85199 583 7

Typeset in Souvenir Light by Columns Design Ltd, Reading

Printed and bound in the UK by Biddles Ltd, Guildford and King’s Lynn

Nutrition00 4/9/02 4:03 PM Page iv

Contents

Contributors vii

Preface ix

Part 1: The Immune System

1. The Immune System: an Overview 1

G. Devereux

2. Evaluation of the Effects of Nutrients on Immune Function 21

S. Cunningham-Rundles

Part 2: Individual Nutrients, Infection and Immune Function

3. Effect of Post-natal Protein Malnutrition and Intrauterine

Growth Retardation on Immunity and Risk of Infection 41

R.K. Chandra

4. Fatty Acids, Inflammation and Immunity 57

P.C. Calder and C.J. Field

5. Arginine and Immune Function 93

M.D. Duff and J.M. Daly

6. Glutamine and the Immune System 109

P.C. Calder and P. Newsholme

7. Sulphur Amino Acids, Glutathione and Immune Function 133

R.F. Grimble

v

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8. Vitamin A, Infection and Immune Function 151

R.D. Semba

9. Antioxidant Vitamins and Immune Function 171

D.A. Hughes

10. Zinc, Infection and Immune Function 193

A.S. Prasad

11. Role of Iron in Immunity and Infection 209

S. Kuvibidila and B.S. Baliga

12. Selenium and the Immune System 229

R.C. McKenzie, J.R. Arthur, S.M. Miller, T.S. Rafferty and G.J. Beckett

13. Probiotics and Immune Function 251

H.S. Gill and M.L. Cross

Part 3: Nutrition and Immunity through the Life Cycle

14. Role of Local Immunity and Breast-feeding in Mucosal

Homoeostasis and Defence against Infections 273

P. Brandtzaeg

15. Food Allergy 321

E. Opara

16. Exercise and Immune Function – Effect of Nutrition 347

E.W. Petersen and B.K. Pedersen

17. Nutrition and Ageing of the Immune System 357

B. Lesourd, A. Raynaud-Simon and L. Mazari

18. Nutrition, Infection and Immunity:

Public Health Implications 375

A. Tomkins

Index 413

vi Contents

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Contributors

J.R. Arthur, Division of Cell Integrity, Rowett Research Institute, Bucksburn,

Aberdeen AB21 9SB, UK.

B.S. Baliga, Department of Pediatrics, College of Medicine, University of South

Alabama, 2451 Fillingim Street, Mobile, AL 36617, USA.

G.J. Beckett, Department of Clinical Biochemistry, University of Edinburgh,

Lauriston Building, Royal Infirmary of Edinburgh, Edinburgh EH3 9YW, UK.

P. Brandtzaeg, Laboratory for Immunohistochemistry and Immunopathology

(LIIPAT), Institute of Pathology, University of Oslo, Rikshospitalet, N-0027

Oslo, Norway.

P.C. Calder, Institute of Human Nutrition, School of Medicine, University of

Southampton, Bassett Crescent East, Southampton SO16 7PX, UK.

R.K. Chandra, Janeway Child Health Centre, Room 2J740, 300 Prince Philip

Drive, St John’s, Newfoundland, Canada A1B 3V6.

M.L. Cross, Institute of Food, Nutrition and Human Health, Massey University,

Palmerston North, New Zealand.

S. Cunningham-Rundles, Immunology Research Laboratory, Division of

Hematology and Oncology, Department of Pediatrics, New York

Presbyterian Hospital, Cornell University Weill Medical College, 1300

York Avenue, New York, NY 10021, USA.

J.M. Daly, Department of Surgery, New York Presbyterian Hospital, Weill

Medical College of Cornell University and 525 East 68th Street, New

York, NY 10021, USA.

G. Devereux, Aberdeen Royal Infirmary, Foresterhill, Aberdeen AB25 2ZD, UK.

M.D. Duff, Department of Surgery, New York Presbyterian Hospital, Weill

Medical College of Cornell University and 525 East 68th Street, New

York, NY 10021, USA.

C.J. Field, Nutrition and Metabolism Research Group, Department of

Agricultural, Food and Nutritional Science, 4–10 Agriculture Forestry

Centre, University of Alberta, Edmonton, Canada T6G 2P5.

vii

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H.S. Gill, Institute of Food, Nutrition and Human Health, Massey University,

Palmerston North, New Zealand.

R.F. Grimble, Institute of Human Nutrition, School of Medicine, University of

Southampton, Bassett Crescent East, Southampton SO16 7PX, UK.

D.A. Hughes, Nutrition and Consumer Science Division, Institute of Food

Research, Norwich Research Park, Norwich NR4 7UA, UK.

S. Kuvibidila, Division of Hematology/Oncology, Department of Pediatrics,

Louisiana State University Health Sciences Center, Box T8-1, 1542

Tulane Avenue, New Orleans, LA 70112, USA.

B. Lesourd, Département de Gérontologie Clinique, Hôpital Nord du CHU de

Clermont-Ferrand, BP 56, 63118 Cébazat, France.

R.C. McKenzie, Department of Medical and Radiological Sciences, University of

Edinburgh, Lauriston Building, Royal Infirmary of Edinburgh, Edinburgh

EH3 9YW, UK. Corresponding address: Section of Dermatology, Lauriston

Building, Royal Infirmary of Edinburgh, Edinburgh EH3 9YW, UK.

L. Mazari, Département de Gérontologie Clinique, Hôpital Nord du CHU de

Clermont-Ferrand, BP 56, 63118 Cébazat, France.

S.M. Miller, Department of Clinical Biochemistry, University of Edinburgh,

Lauriston Building, Royal Infirmary of Edinburgh, Edinburgh EH3 9YW, UK.

P. Newsholme, Department of Biochemistry, Conway Institute of Biomolecular

and Biomedical Research, University College Dublin, Belfield, Dublin 4,

Republic of Ireland.

E. Opara, School of Life Sciences, Kingston University and Faculty of Health

and Social Care Sciences, St George’s Hospital Medical School, Penrhyn

Road, Kingston upon Thames, Surrey KT1 2EE, UK.

B.K. Pedersen, Copenhagen Muscle Research Centre and Department of

Infectious Diseases, Rigshospitalet, University of Copenhagen, Tagensvej

20, 2200 Copenhagen N, Denmark.

E.W. Petersen, Copenhagen Muscle Research Centre and Department of

Infectious Diseases, Rigshospitalet, University of Copenhagen, Tagensvej

20, 2200 Copenhagen N, Denmark.

A.S. Prasad, Division of Hematology and Oncology, Department of Internal

Medicine, Wayne State University School of Medicine, 4201 St Antoine,

Detroit, MI 48201, USA.

T.S. Rafferty, Department of Medical and Radiological Sciences, University of

Edinburgh, Lauriston Building, Royal Infirmary of Edinburgh, Edinburgh

EH3 9YW, UK.

A. Raynaud-Simon, Département de Gérontologie Clinique, Hôpital Nord du

CHU de Clermont-Ferrand, BP 56, 63118 Cébazat, France.

R.D. Semba, Department of Opthalmology, Johns Hopkins University School

of Medicine, Baltimore, MD 21205, USA. Correspondence address:

550 North Broadway, Suite 700, Baltimore, MD 21205, USA.

A. Tomkins, Centre for International Child Health, Institute of Child Health, 30

Guilford Street, London WC1N 1EH, UK.

viii Contributors

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Preface

‘This fortress built by Nature for herself

Against infection and hand of war’

(The Tragedy of King Richard II, Act II, Scene I, lines 43 and 44,

William Shakespeare)

It has been recognized for many years that states of nutrient deficiency are associ￾ated with an impaired immune response and with increased susceptibility to infec￾tious disease. In turn, infection can affect the status of several nutrients, thus setting

up a vicious circle of under nutrition, compromised immune function and infec￾tion. Thus, the focus of much of the research into nutrition, infection and immu￾nity has been related to identifying the effects of nutrient deficiencies upon

components of the immune response (often using animal models) and, impor￾tantly, upon attempts to reduce the occurrence and severity of infectious diseases

(often in human settings). Although it is often considered that the problems of

under nutrition relate mainly to the developing world, they exist in developed

countries, especially among the elderly, individuals with eating disorders, alco￾holics, patients with certain diseases and premature and small-for-gestational-age

babies. Thus, immunological problems in these groups probably relate, at least in

part, to nutrient status. In addition, many diseases that exist among the apparently

well nourished have a strong immunological component and it is now recognized

that at least some of these diseases relate to diet and that their course may be

modified by specific changes in nutrient supply. Examples of these diseases

include rheumatoid arthritis, Crohn’s disease and atopic diseases. Furthermore, it

is now recognized that atherosclerosis, a disease strongly influenced by diet, has

an immunological component. Thus, understanding the interaction between nutri￾tion and immune function is fundamental to understanding the development of a

multitude of communicable and non-communicable diseases and will offer pre￾ventive and therapeutic opportunities to control the incidence and severity of

those diseases. It is also now recognized that immune dysfunction plays a role in

ix

Nutrition00 4/9/02 4:03 PM Page ix

the events that follow trauma, burns or major surgery, and which, in some

patients, can lead to organ failure and death. Thus, understanding the interaction

between nutrition and immune function is fundamental in designing therapies to

control the severity of these aberrant responses and to improve patient outcome.

The aim of this book is to provide a state of the art description of the inter￾action between nutrition and immunity, with an emphasis on the mechanism(s)

of action of the nutrients concerned and the impact on human health. The

book is divided into three parts.

Part 1 contains two chapters. The first is an overview of the immune sys￾tem, its components and the way in which it functions and regulates its activi￾ties. The second is a description, using examples from the recent literature, of

the methodological approaches that can be used to investigate the impact of

altered nutrient supply on immune outcomes.

Part 2 contains 11 chapters. The first of these is devoted to the immunolog￾ical effects of protein–energy malnutrition and of intrauterine growth retarda￾tion. Each of a further nine chapters is devoted to a specific nutrient or a family

of nutrients: fatty acids, arginine, glutamine, sulphur amino acids, vitamin A,

antioxidant vitamins (vitamins C and E and -carotene), zinc, iron and sele￾nium are all featured. The final chapter in this section deals with probiotics, an

emerging area of great interest.

Part 3 contains five chapters. Rather than taking a nutrient-led approach

these deal with changes in immune competence through the life cycle and with

how nutrition affects these. The development of immunity in early life and the

role of breast-feeding are covered in one chapter. A later chapter describes the

current understanding of the impact of ageing on immune competence and

how nutrient status plays a role in accelerating or delaying this ageing process.

In between these two chapters are chapters on food allergy and on the influ￾ence of exercise on immune function. The final chapter tackles the public

health implications of our increased understanding of the interaction between

nutrition and immune function and poses important questions about how we

can harness our knowledge for greater benefit.

Each chapter of this book includes an extensive reference list, which will

guide the reader who wishes to seek more detailed information.

The true remedy for all diseases is Nature’s remedy. Nature and Science

are at one … Nature has provided, in the white corpuscles as you call them

– in the phagocytes as we call them – a natural means of devouring and

destroying all disease germs. There is at bottom only one genuinely

scientific treatment for all diseases, and that is to stimulate the phagocytes.

Stimulate the phagocytes… The phagocytes are stimulated; they devour

the disease; and the patient recovers.

The Doctor’s Dilemma, Bernard Shaw

P.C. Calder, C.J. Field and H.S. Gill

Editors

December 2001

x Preface

Nutrition00 4/9/02 4:03 PM Page x

Preface

‘This fortress built by Nature for herself

Against infection and hand of war’

(The Tragedy of King Richard II, Act II, Scene I, lines 43 and 44,

William Shakespeare)

It has been recognized for many years that states of nutrient deficiency are associ￾ated with an impaired immune response and with increased susceptibility to infec￾tious disease. In turn, infection can affect the status of several nutrients, thus setting

up a vicious circle of under nutrition, compromised immune function and infec￾tion. Thus, the focus of much of the research into nutrition, infection and immu￾nity has been related to identifying the effects of nutrient deficiencies upon

components of the immune response (often using animal models) and, impor￾tantly, upon attempts to reduce the occurrence and severity of infectious diseases

(often in human settings). Although it is often considered that the problems of

under nutrition relate mainly to the developing world, they exist in developed

countries, especially among the elderly, individuals with eating disorders, alco￾holics, patients with certain diseases and premature and small-for-gestational-age

babies. Thus, immunological problems in these groups probably relate, at least in

part, to nutrient status. In addition, many diseases that exist among the apparently

well nourished have a strong immunological component and it is now recognized

that at least some of these diseases relate to diet and that their course may be

modified by specific changes in nutrient supply. Examples of these diseases

include rheumatoid arthritis, Crohn’s disease and atopic diseases. Furthermore, it

is now recognized that atherosclerosis, a disease strongly influenced by diet, has

an immunological component. Thus, understanding the interaction between nutri￾tion and immune function is fundamental to understanding the development of a

multitude of communicable and non-communicable diseases and will offer pre￾ventive and therapeutic opportunities to control the incidence and severity of

those diseases. It is also now recognized that immune dysfunction plays a role in

ix

Nutrition00 4/9/02 4:03 PM Page ix

the events that follow trauma, burns or major surgery, and which, in some

patients, can lead to organ failure and death. Thus, understanding the interaction

between nutrition and immune function is fundamental in designing therapies to

control the severity of these aberrant responses and to improve patient outcome.

The aim of this book is to provide a state of the art description of the inter￾action between nutrition and immunity, with an emphasis on the mechanism(s)

of action of the nutrients concerned and the impact on human health. The

book is divided into three parts.

Part 1 contains two chapters. The first is an overview of the immune sys￾tem, its components and the way in which it functions and regulates its activi￾ties. The second is a description, using examples from the recent literature, of

the methodological approaches that can be used to investigate the impact of

altered nutrient supply on immune outcomes.

Part 2 contains 11 chapters. The first of these is devoted to the immunolog￾ical effects of protein–energy malnutrition and of intrauterine growth retarda￾tion. Each of a further nine chapters is devoted to a specific nutrient or a family

of nutrients: fatty acids, arginine, glutamine, sulphur amino acids, vitamin A,

antioxidant vitamins (vitamins C and E and -carotene), zinc, iron and sele￾nium are all featured. The final chapter in this section deals with probiotics, an

emerging area of great interest.

Part 3 contains five chapters. Rather than taking a nutrient-led approach

these deal with changes in immune competence through the life cycle and with

how nutrition affects these. The development of immunity in early life and the

role of breast-feeding are covered in one chapter. A later chapter describes the

current understanding of the impact of ageing on immune competence and

how nutrient status plays a role in accelerating or delaying this ageing process.

In between these two chapters are chapters on food allergy and on the influ￾ence of exercise on immune function. The final chapter tackles the public

health implications of our increased understanding of the interaction between

nutrition and immune function and poses important questions about how we

can harness our knowledge for greater benefit.

Each chapter of this book includes an extensive reference list, which will

guide the reader who wishes to seek more detailed information.

The true remedy for all diseases is Nature’s remedy. Nature and Science

are at one … Nature has provided, in the white corpuscles as you call them

– in the phagocytes as we call them – a natural means of devouring and

destroying all disease germs. There is at bottom only one genuinely

scientific treatment for all diseases, and that is to stimulate the phagocytes.

Stimulate the phagocytes… The phagocytes are stimulated; they devour

the disease; and the patient recovers.

The Doctor’s Dilemma, Bernard Shaw

P.C. Calder, C.J. Field and H.S. Gill

Editors

December 2001

x Preface

Nutrition00 4/9/02 4:03 PM Page x

Contributors

J.R. Arthur, Division of Cell Integrity, Rowett Research Institute, Bucksburn,

Aberdeen AB21 9SB, UK.

B.S. Baliga, Department of Pediatrics, College of Medicine, University of South

Alabama, 2451 Fillingim Street, Mobile, AL 36617, USA.

G.J. Beckett, Department of Clinical Biochemistry, University of Edinburgh,

Lauriston Building, Royal Infirmary of Edinburgh, Edinburgh EH3 9YW, UK.

P. Brandtzaeg, Laboratory for Immunohistochemistry and Immunopathology

(LIIPAT), Institute of Pathology, University of Oslo, Rikshospitalet, N-0027

Oslo, Norway.

P.C. Calder, Institute of Human Nutrition, School of Medicine, University of

Southampton, Bassett Crescent East, Southampton SO16 7PX, UK.

R.K. Chandra, Janeway Child Health Centre, Room 2J740, 300 Prince Philip

Drive, St John’s, Newfoundland, Canada A1B 3V6.

M.L. Cross, Institute of Food, Nutrition and Human Health, Massey University,

Palmerston North, New Zealand.

S. Cunningham-Rundles, Immunology Research Laboratory, Division of

Hematology and Oncology, Department of Pediatrics, New York

Presbyterian Hospital, Cornell University Weill Medical College, 1300

York Avenue, New York, NY 10021, USA.

J.M. Daly, Department of Surgery, New York Presbyterian Hospital, Weill

Medical College of Cornell University and 525 East 68th Street, New

York, NY 10021, USA.

G. Devereux, Aberdeen Royal Infirmary, Foresterhill, Aberdeen AB25 2ZD, UK.

M.D. Duff, Department of Surgery, New York Presbyterian Hospital, Weill

Medical College of Cornell University and 525 East 68th Street, New

York, NY 10021, USA.

C.J. Field, Nutrition and Metabolism Research Group, Department of

Agricultural, Food and Nutritional Science, 4–10 Agriculture Forestry

Centre, University of Alberta, Edmonton, Canada T6G 2P5.

vii

Nutrition00 4/9/02 4:03 PM Page vii

H.S. Gill, Institute of Food, Nutrition and Human Health, Massey University,

Palmerston North, New Zealand.

R.F. Grimble, Institute of Human Nutrition, School of Medicine, University of

Southampton, Bassett Crescent East, Southampton SO16 7PX, UK.

D.A. Hughes, Nutrition and Consumer Science Division, Institute of Food

Research, Norwich Research Park, Norwich NR4 7UA, UK.

S. Kuvibidila, Division of Hematology/Oncology, Department of Pediatrics,

Louisiana State University Health Sciences Center, Box T8-1, 1542

Tulane Avenue, New Orleans, LA 70112, USA.

B. Lesourd, Département de Gérontologie Clinique, Hôpital Nord du CHU de

Clermont-Ferrand, BP 56, 63118 Cébazat, France.

R.C. McKenzie, Department of Medical and Radiological Sciences, University of

Edinburgh, Lauriston Building, Royal Infirmary of Edinburgh, Edinburgh

EH3 9YW, UK. Corresponding address: Section of Dermatology, Lauriston

Building, Royal Infirmary of Edinburgh, Edinburgh EH3 9YW, UK.

L. Mazari, Département de Gérontologie Clinique, Hôpital Nord du CHU de

Clermont-Ferrand, BP 56, 63118 Cébazat, France.

S.M. Miller, Department of Clinical Biochemistry, University of Edinburgh,

Lauriston Building, Royal Infirmary of Edinburgh, Edinburgh EH3 9YW, UK.

P. Newsholme, Department of Biochemistry, Conway Institute of Biomolecular

and Biomedical Research, University College Dublin, Belfield, Dublin 4,

Republic of Ireland.

E. Opara, School of Life Sciences, Kingston University and Faculty of Health

and Social Care Sciences, St George’s Hospital Medical School, Penrhyn

Road, Kingston upon Thames, Surrey KT1 2EE, UK.

B.K. Pedersen, Copenhagen Muscle Research Centre and Department of

Infectious Diseases, Rigshospitalet, University of Copenhagen, Tagensvej

20, 2200 Copenhagen N, Denmark.

E.W. Petersen, Copenhagen Muscle Research Centre and Department of

Infectious Diseases, Rigshospitalet, University of Copenhagen, Tagensvej

20, 2200 Copenhagen N, Denmark.

A.S. Prasad, Division of Hematology and Oncology, Department of Internal

Medicine, Wayne State University School of Medicine, 4201 St Antoine,

Detroit, MI 48201, USA.

T.S. Rafferty, Department of Medical and Radiological Sciences, University of

Edinburgh, Lauriston Building, Royal Infirmary of Edinburgh, Edinburgh

EH3 9YW, UK.

A. Raynaud-Simon, Département de Gérontologie Clinique, Hôpital Nord du

CHU de Clermont-Ferrand, BP 56, 63118 Cébazat, France.

R.D. Semba, Department of Opthalmology, Johns Hopkins University School

of Medicine, Baltimore, MD 21205, USA. Correspondence address:

550 North Broadway, Suite 700, Baltimore, MD 21205, USA.

A. Tomkins, Centre for International Child Health, Institute of Child Health, 30

Guilford Street, London WC1N 1EH, UK.

viii Contributors

Nutrition00 4/9/02 4:03 PM Page viii

1 The Immune System:

an Overview

GRAHAM DEVEREUX

Aberdeen Royal Infirmary, Foresterhill, Aberdeen AB25 2ZD, UK

Introduction

To parasitic microorganisms, the human body represents an extremely attrac￾tive environment and source of nutrients. Consequently, we live under the con￾stant threat of overwhelming attack by viruses, bacteria and parasites.

Microorganisms evolve more rapidly than humans, so that the nature of the

microbiological threat to humans is changing as exposure to new or variant

organisms occurs. To combat this potentially devastating threat, evolution has

provided humans with a highly sophisticated, flexible and potent immune

system, which is able to protect humans against rapidly evolving microorgan￾isms. The critical protective function of the immune system becomes apparent

when it fails. The inherited and acquired immunodeficiency states are charac￾terized by increased susceptibility to all infections, including those organisms

not normally considered to be pathogenic.

The immune system is a two-edged sword: the extremely potent and toxic

biological effector mechanisms of the immune system can destroy not only

threatening microorganisms but also body tissues. Usually the tissue destruction

and inflammation associated with the eradication of a microbiological threat

are acceptable and functionally insignificant. However, in several human

diseases, the immunologically associated tissue destruction and inflammation

are harmful, e.g. tuberculosis, fulminant hepatitis and meningitis, and, although

this may be advantageous to the species as a whole, the effect on the individ￾ual may be devastating. It is because of their potential to destroy tissues that

the effector mechanisms of the immune system are very tightly regulated.

Failure of these regulatory mechanisms results in the full might of the immune

system being inappropriately directed against body tissues and the develop￾ment of autoimmune diseases, such as rheumatoid arthritis, systemic lupus

erythematosus (SLE), myasthenia gravis and multiple sclerosis. If immune

responses are directed against innocuous targets, such as allergens or transplanted

© CAB International 2002. Nutrition and Immune Function

(eds P.C. Calder, C.J. Field and H.S. Gill) 1

Nutrition Chapter 01 4/9/02 4:03 PM Page 1