Modulation of cell-mediated immunity during pregnancy in wild bonobos

During pregnancy, the mammalian immune system must simultaneously protect against pathogens while being accommodating to the foreign fetal tissues. Our current understanding of this immune modulation derives predominantly from industrialized human populations and laboratory animals. However, their environments differ considerably from the pathogen-rich, resource-scarce environments in which pregnancy and the immune system co-evolved. For a better understanding of immune modulation during pregnancy in challenging environments, we measured urinary neopterin, a biomarker of cell-mediated immune responses, in 10 wild female bonobos (Pan paniscus) before, during and after pregnancy. Bonobos, sharing evolutionary roots and pregnancy characteristics with humans, serve as an ideal model for such investigation. Despite distinct environments, we hypothesized that cell-mediated immune modulation during pregnancy is similar between bonobos and humans. As predicted, neopterin levels were higher during than outside of pregnancy, and highest in the third trimester, with a significant decline post-partum. Our findings suggest shared mechanisms of cell-mediated immune modulation during pregnancy in bonobos and humans that are robust despite distinct environmental conditions. We propose that these patterns indicate shared immunological processes during pregnancy among hominins, and possibly other primates. This finding enhances our understanding of reproductive immunology.

Association between neopterin in cord blood, urinary neopterin in early childhood and the development of atopic dermatitis, asthma and hay fever

It is generally accepted that the increased prevalence of atopic disease is due to a disturbed balance of T-helper (Th)1/Th2-type immunity. Upon stimulation by the Th1-type cytokine interferon (IFN)-gamma, human monocytes/macrophages release large amounts of neopterin. Thus, the determination of neopterin concentrations is an indirect measure of the levels of IFN-gamma and allows us to monitor Th1-type immune response. We evaluated whether neopterin concentrations in the neonatal cord blood could be a valuable marker predicting atopic disease in early childhood and whether there is a difference in actually determined urinary neopterin concentrations in children with and without atopic disease. Five hundred and five children born during 1997-1999 were enrolled, with cord blood neopterin data available at birth. The International study of asthma and allergies in childhood (ISAAC) questionnaire was used to assess the prevalence of wheezy bronchitis (asthma), atopic dermatitis and allergic rhinitis. Morning urinary samples were collected and urinary neopterin concentration was measured by high-pressure liquid chromatography. By the average age of 6 yr, the prevalence of atopic disease in the last 12 months was 31%. There was no significant correlation between cord blood and urinary neopterin concentrations at age 6 yr, and between cord blood neopterin and later atopic disease. Urinary neopterin concentrations were significant lower in children with a family history of atopic disease (p = 0.02). In this study, cord blood neopterin concentration was not a predictor for atopic disease in early childhood. Family history of atopic disease was associated with lower urinary neopterin levels at age 6 yr, which might mirror a Th1/Th2 imbalance.

Urinary neopterin levels in the different stages of pregnancy

BACKGROUND/AIMS

Neopterin is a biochemical marker of activated cell-mediated immune response which increases in pathological conditions associated with cellular immune activation as well as in pregnancy where cellular immune response is predominant. The aim of this study was to determine the urinary neopterin level in each trimester of pregnancy and to determine if it can be used as a marker.

METHODS

104 healthy pregnant women (mean age 22.10 +/- 4.39 years; 36 in the first, 30 in the second and 38 in the third trimester) and 16 non-pregnant healthy women (mean age 20.94 +/- 4.48 year) were included.

RESULTS

The mean urinary neopterin concentration of all pregnant women was higher than that of non-pregnant women (166.4 +/- 31.7 and 103.1 +/- 27.5 micromol/mol creatinine respectively, p < 0.01). The mean urinary neopterin levels in each trimester and non-pregnant women were 139.8 +/- 49.6, 131 +/- 40.2, 227.9 +/- 86.5 and 103.1 +/- 27.5 micromol/mol creatinine, respectively. Urinary neopterin levels were not significantly different between non-pregnant, first and second trimester groups, but were significantly higher in the third trimester than each of these groups (p < 0.05, p < 0.01 and p < 0.01 respectively).

CONCLUSION

Urinary neopterin levels increase significantly in the third trimester probably due to more predominated cellular immunity. The pathologies causing cellular immune activation, especially in the first two trimesters can be predicted with urinary neopterin levels.