Telethon Institute for Child Health Research, Centre for Child Health Research, University of Western Australia, Perth, Australia.
Pediatr Allergy Immunol. 2012 Mar;23(2):173-80. doi: 10.1111/j.1399-3038.2011.01242.x. Epub 2011 Dec 23.
Environmental changes, including declining microbial exposure, have been linked with the rising incidence of allergic and autoimmune diseases in 'western' populations. This potentially occurs by altering early development of immuno-regulatory pathways including T regulatory cells (T(reg)). There is now increasing evidence that such conditioning begins in utero.
We compared neonatal T(reg) from children born under typical western conditions (Australia, AUS) with those of neonates born under more traditional conditions of high microbial burden (Papua New Guinea, PNG).
The frequency of neonatal T(reg), defined as CD4(+) Foxp3(+) CD127(-) CD25(+/high) was found to be higher in the cord blood of AUS compared to PNG newborns. However, cord T(reg) suppressive function in a small subset of children was qualitatively similar between PNG and AUS newborns in both a T(reg) depletion assay and a T(reg) supplementation assay.
These findings do not support the hypothesis that living in a 'western' versus more traditional environment leads to poor induction or suppressive function of neonatal T(reg). However, environmentally-induced immuno-regulation may potentially occur via alternative mechanisms in PNG newborns that should now be investigated further.
环境变化，包括微生物暴露的减少，与“西方”人群中过敏和自身免疫性疾病发病率的上升有关。这可能通过改变包括调节性 T 细胞（Treg）在内的免疫调节途径的早期发育来实现。现在越来越多的证据表明，这种调节作用始于宫内。
我们比较了在典型西方条件（澳大利亚，AUS）下出生的儿童的新生儿 Treg 与在微生物负担较高的传统条件（巴布亚新几内亚，PNG）下出生的新生儿的 Treg。
与 PNG 新生儿相比，AUS 新生儿脐带血中 CD4+Foxp3+CD127-CD25+Treg 的频率更高。然而，在 Treg 耗竭试验和 Treg 补充试验中，一小部分儿童的脐带 Treg 抑制功能在 PNG 和 AUS 新生儿之间在质量上是相似的。
这些发现并不支持生活在“西方”与更传统的环境中会导致新生儿 Treg 诱导或抑制功能不良的假设。然而，环境诱导的免疫调节可能通过 PNG 新生儿中的其他机制发生，现在应进一步研究。
