Species comparison of anatomical and functional immune system development

Abstract

The components of the immune system have not been traditionally emphasized as potential target organs in standard developmental and reproductive toxicity (DART) protocols. A number of workshops have been organized in recent years to examine scientific questions that underlie developmental immunotoxicity tests, and the interpretation of results as they relate to human risk assessment. A key question that must be addressed is to determine the most appropriate species and strains to model the developing human immune system. The objective of this review is to compare the anatomical and functional development of the immune system in several species important to either preclinical studies for drug development or safety assessments for chemicals, with what is known in humans. The development of the immune system in humans will be compared to what is known in mice, rats, dogs and nonhuman primates.

Expressing urine from a gel disposable diaper for biomonitoring using phthalates as an example

“…Lymphocyte progenitors are present in the liver by weeks 7-8 of gestation (Migliaccio et al, 1986). Holsapple et al (2003) discuss the evidence indicating that lineage-specific progenitors are at potential risk by 7-10 weeks postconception. Around this same window, the thymus stroma forms and T cell progenitors migrate from the liver to the thymus.…”

“…The immune and haematopoietic systems arise from pleuripotent stem cells (West, 2002;Holsapple et al, 2003). As gestational development proceeds, these give rise to haematopoietic for the various endocrine components are discussed in section 4.3.3.…”

“…West (2002) discusses lymphogenesis within the human bone marrow that emerges within this same window of susceptibility. In general, early B and T cell differentiation seem to occur in parallel (Holsapple et al, 2003). The thymic medulla and cortex areas begin to differentiate during the first trimester, and the areas are fully formed with maturational cell migration from the cortex to the medulla in the subsequent trimester (West, 2002).…”

“…The development of the immune system as it relates to comparative developmental toxicology has been considered in several publications over the last decade (Barnett, 1996;Dietert et al, 2000;Holladay & Smialowicz, 2000;Chapin, 2002;Holladay & Blaylock, 2002;Holsapple, 2002;Holsapple et al, 2003;Luster et al, 2003;Luebke et al, 2004). Immune development is a dynamic process involving cellular proliferation, migration, recognition, selection, apoptosis, clonal expansion, dissemination to peripheral sites, and, finally, cell cooperation and function.…”

Prenatal stress, immunity and neonatal health in farm animal species

“…Species that give birth to non-precocious offspring (rats, rabbits and mice) have a large proportion of immune development during late gestation and the postnatal period (Holladay and Smialowicz, 2000;Holsapple et al, 2003). By contrast, animals that give birth to precocious offspring (sheep, pig, cattle and primates) display development of the immune system predominantly in utero (Trebichavský et al, 1996;Sinkora et al, 2005).…”