Skip to main page content
U.S. flag

An official website of the United States government

Dot gov

The .gov means it’s official.
Federal government websites often end in .gov or .mil. Before sharing sensitive information, make sure you’re on a federal government site.

Https

The site is secure.
The https:// ensures that you are connecting to the official website and that any information you provide is encrypted and transmitted securely.

Access keys NCBI Homepage MyNCBI Homepage Main Content Main Navigation
. 2023 Sep 7:140:11-19.
doi: 10.1016/j.placenta.2023.07.011. Epub 2023 Jul 23.

Are high avidity antibodies to Plasmodium falciparum antigens preferentially transferred across the placenta of premature and term babies?

Alexander K K Kayatani  1 , Naveen Bobbili  2 , Rosette Megnekou  3 , Masako Matsunaga  4 , Rose F G Leke  5 , Diane Wallace Taylor  6
Affiliations

Are high avidity antibodies to Plasmodium falciparum antigens preferentially transferred across the placenta of premature and term babies?

Alexander K K Kayatani et al. Placenta. .

Abstract

Introduction: Transplacental transport of maternal IgG via the neonatal Fc receptor (FcRn) provides babies with passive immunity. Several factors are reported to influence transport, including the avidity of antibodies (Abs) for their cognate antigens. Unfortunately, information on the role of antibody (Ab) avidity is limited. This study investigated if i) antibodies (Abs) with high avidity for 6 Plasmodium falciparum antigens and tetanus toxoid (TTx) were preferentially transferred to premature and term Cameroonian babies and ii) if Ab avidity was increased in babies whose mothers had placental malaria (PM), implicating the involvement of immune complexes.

Methods: Total IgG (mg/ml) and Abs to malarial antigens (AMA1, EBA-175, MSP1-42, MSP2, MSP3, DBL5 of VAR2CSA) and TTx were measured in paired mother-cord samples obtained from premature and term deliveries in Cameroon. Half the women had PM at delivery. Avidity Indices (AIs) were determined by treating antigen-bound-Abs with different molar concentrations of NH4SCN and calculating 50% endpoints.

Results: Total IgG and antigen-specific Abs increased in cord blood with gestational age; however, AIs did not. AIs in paired maternal-cord blood samples were strongly associated for all antigens (r = 0.77-0.96). However, no significant different in AIs was found between paired mother-cord blood samples for any of the antigens (p values > 0.05). Similarly, Ab avidity was not increased in cord blood of babies whose mothers had PM or hypergammaglobulinemia.

Discussion: Overall, there was no evidence that higher avidity Abs to any of the malarial antigens or TTx were preferentially transferred to Cameroonian babies.

Keywords: Antibody avidity; FcRn; Malaria; Maternal IgG; Transplacental transfer.

PubMed Disclaimer

Conflict of interest statement

Declaration of competing interest All authors declare they have no real or perceived conflict of interests.

Figures

Figure 1:
Figure 1:. Total IgG in maternal and cord blood and CMR during gestation.
(A) Total IgG (mg/ml). (B) Cord to Mother ratio (CMR). Horizontal lines and error bars represent means ±SD. Differences between Groups were examined by post-hoc comparison tests. Mothers: n = 60; ≤33 wks, n=18; 34-37 wks. n=12; >37b wks, n=29.
Figure 2.
Figure 2.. Antibody Levels (MFI) to malarial antigens and TTx at different gestational ages.
Antibody levels in maternal (M) and cord (C) blood are shown at different gestational ages. All significant p where mother-baby Ab levels differ are shown (Wilcoxon matched pairs sign rank test). Cord to Mother Ratio (CMR): Mean ± SD from 34 weeks to term.
Figure 3.
Figure 3.. Box plots of avidity indices (AIs) in maternal and cord blood.
Paired maternal and cord blood AI are shown for all Ab-positive pairs. The center horizontal line in the box is the median. P-values were obtained by paired t test.
See this image and copyright information in PMC

References

    1. Roopenian DC, Akilesh S, FcRn: The neonatal Fc receptor comes of age, Nat Rev Immunol. 7 (2007) 715–725. 10.1038/nri2155. - DOI - PubMed
    1. Malek A, Sager R, Kuhn P, Nicolaides KH, Schneider H, Evolution of maternofetal transport of immunoglobulins during human pregnancy, American Journal of Reproductive Immunology. 36 (1996) 248–255. 10.1111/j.1600-0897.1996.tb00172.x. - DOI - PubMed
    1. Yeung C, Hobbs J, Serum-γg-globulin levels in normal, premature, and “small-for-dates” newborn babies, The Lancet. (1968) 1167–1170. - PubMed
    1. Garty BZ, Ludomirsky A, Danon YL, Peter JB, Douglas SD, Placental transfer of immunoglobulin G subclasses, Clinical Diagnostic Laboratory Immunology. 1 (1994) 667–669. 10.1128/cdli.1.6.667-669.1994. - DOI - PMC - PubMed
    1. van den Berg JP, Westerbeek EAM, van der Klis FRM, Berbers GAM, van Elburg RM, Transplacental transport of IgG antibodies to preterm infants: A review of the literature, Early Hum Dev. 87 (2011) 67–72. 10.1016/j.earlhumdev.2010.11.003. - DOI - PubMed

Publication types

LinkOut - more resources