TY - JOUR

T1 - T helper cell 2 immune skewing in pregnancy/early life

T2 - chemical exposure and the development of atopic disease and allergy

AU - McFadden, J P

AU - Thyssen, J P

AU - Basketter, D A

AU - Puangpet, P

AU - Kimber, I

N1 - © 2014 British Association of Dermatologists.

PY - 2015/3

Y1 - 2015/3

N2 - During the last 50 years there has been a significant increase in Western societies of atopic disease and associated allergy. The balance between functional subpopulations of T helper cells (Th) determines the quality of the immune response provoked by antigen. One such subpopulation - Th2 cells - is associated with the production of IgE antibody and atopic allergy, whereas, Th1 cells antagonize IgE responses and the development of allergic disease. In seeking to provide a mechanistic basis for this increased prevalence of allergic disease, one proposal has been the 'hygiene hypothesis', which argues that in Westernized societies reduced exposure during early childhood to pathogenic microorganisms favours the development of atopic allergy. Pregnancy is normally associated with Th2 skewing, which persists for some months in the neonate before Th1/Th2 realignment occurs. In this review, we consider the immunophysiology of Th2 immune skewing during pregnancy. In particular, we explore the possibility that altered and increased patterns of exposure to certain chemicals have served to accentuate this normal Th2 skewing and therefore further promote the persistence of a Th2 bias in neonates. Furthermore, we propose that the more marked Th2 skewing observed in first pregnancy may, at least in part, explain the higher prevalence of atopic disease and allergy in the first born.

AB - During the last 50 years there has been a significant increase in Western societies of atopic disease and associated allergy. The balance between functional subpopulations of T helper cells (Th) determines the quality of the immune response provoked by antigen. One such subpopulation - Th2 cells - is associated with the production of IgE antibody and atopic allergy, whereas, Th1 cells antagonize IgE responses and the development of allergic disease. In seeking to provide a mechanistic basis for this increased prevalence of allergic disease, one proposal has been the 'hygiene hypothesis', which argues that in Westernized societies reduced exposure during early childhood to pathogenic microorganisms favours the development of atopic allergy. Pregnancy is normally associated with Th2 skewing, which persists for some months in the neonate before Th1/Th2 realignment occurs. In this review, we consider the immunophysiology of Th2 immune skewing during pregnancy. In particular, we explore the possibility that altered and increased patterns of exposure to certain chemicals have served to accentuate this normal Th2 skewing and therefore further promote the persistence of a Th2 bias in neonates. Furthermore, we propose that the more marked Th2 skewing observed in first pregnancy may, at least in part, explain the higher prevalence of atopic disease and allergy in the first born.

KW - Allergens

KW - Birth Order

KW - Disease Susceptibility

KW - Environmental Exposure

KW - Environmental Pollutants

KW - Female

KW - Fetal Blood

KW - Humans

KW - Hygiene

KW - Hypersensitivity, Immediate

KW - Male

KW - Maternal Exposure

KW - Paternal Exposure

KW - Pregnancy

KW - Pregnancy Complications

KW - Prenatal Exposure Delayed Effects

KW - Th2 Cells

U2 - 10.1111/bjd.13497

DO - 10.1111/bjd.13497

M3 - Review

C2 - 25354210

VL - 172

SP - 584

EP - 591

JO - British Journal of Dermatology

JF - British Journal of Dermatology

SN - 0007-0963

IS - 3

ER -