The Evolution of the Immune System

Conservation and Diversification

Davide Malagoli, Davide Malagoli

• Publisher: Academic Press
• Year: 2016
• ISBN:
  9780128020135
• Topic: Medicine
• Subtopic: Immunology

The Evolution of the Immune System: Conservation and Diversification is the first book of its kind that prompts a new perspective when describing and considering the evolution of the immune system. Its unique approach summarizes, updates, and provides new insights on the different immune receptors, soluble factors, and immune cell effectors.

• Helps the reader gain a modern idea of the evolution of the immune systems in pluricellular organisms
• Provides a complete overview of the most studied and hot topics in comparative and evolutionary immunology
• Reflects the organisation of the immune system (cell-based, humoral [innate], humoral [adaptive]) without introducing further and misleading levels of organization
• Brings concepts and ideas on the evolution of the immune system to a wide readership

Chapter 1

Hematopoiesis and Hemocytes in Pancrustacean and Molluscan Models

Valerie J. Smith^*

Alice Accorsi^**,†

Davide Malagoli^‡
* Scottish Oceans Institute, School of Biology, University of St Andrews, St Andrews, Fife, United Kingdom
^** Stowers Institute for Medical Research, Kansas City, MO, United States
^† Howard Hughes Medical Institute, Stowers Institute for Medical Research, Kansas City, MO, United States
^‡ Department of Life Sciences, Biology Building, University of Modena and Reggio Emilia, Modena, Italy

Abstract

The hematopoietic districts and their organization are here described in detail for some of the principal pancrustacean and molluscan models. Pancrustaceans present an overall similar organization of hematopoietic organs, while among mollusks the hematopoietic organs and tissues are more diversified. The morphologies, functions, and main lineages of circulating hemocytes are recapitulated, and the common traits between different taxa are evidenced.

Keywords

decapods

encapsulation

hematopoiesis

hemocyte lineages

hemocyte proliferation, host defense

insects

invertebrate immunity

mollusks

phagocytosis

1. Introduction

All animals are at risk of damage from microorganisms, parasites, toxins, abrasive particles, or other threats that may kill or bring about somatic cell or tissue injury with longer-term detriment to health. The immune system is the key player in implementing surveillance and response to counter such threats, and the efficacy of its recognition and reactivity abilities is independent of the taxonomic or phylogenetic status of the species. This holds true for both long- and short-lived species, and both vertebrates and invertebrates.

Invertebrate immune systems are often divided into cellular and humoral components.¹ Cellular components include the circulating blood cells, called hemocytes, as the dominant representatives. The renewal of hemocytes is usually referred to as hematopoiesis or hemopoiesis.² The existing literature on invertebrate hematopoiesis is greatly exceeded by that on hemocyte morphology and functions. Notwithstanding, comparative studies on hematopoiesis are crucial for the understanding of the molecular basis of hemocyte proliferation, differentiation, and maturation, especially in models of economic relevance. For mammals and most other vertebrates, which have both i...