All issues > Volume 38(12); 1995

Original Article

J Korean Pediatr Soc. 1995;38(12):1638-1644. Published online December 15, 1995.

Placental Transfer of Anti-H. influenzae Type b Specific IgG and IgG Subclasses

Soo Hee SH Chang¹, Moon Hwan MH Lee¹, Pyoung Han PH Hwang¹, Soo Chul SC Cho¹, Jung Soo JS Kim¹

¹Department of Pediatrics, Chonbuk National University, College of Medical, Chonju, Korea

Abstract

Purpose
: Haemophilus injluenzae type b (Hib) is one of the most important causes of invasive bacterial diseases in infants and children. In Korea, however, the proportion occupied by Hib as a cause of pediatric pathogen seems to be less compared to those of western countries. This study was performed to provide the epidemiologic and immunologic basis of H influenzae type b infection.
Methods
: Anti-PRP IgG and IgG subclasses were measured in the paired sera of fourty mothers and babies using indirect enzyme-linked immunosorbent assay(ELISA).
Results
: The geometric mean titers(GMTs) of anti-PRP IgG in the sera of mothers and babies were 1.35ug/ml and 1.28ug/ml respectively with transplacental transfer rate of 0.95. The GMTs of anti-Hib IgG1 and IgG2 in the sera of mothers and babies were 0.26/0.27ug/ml and 0.92/0.83ug/ml, showing the transplacental transfer rate of 1.02 and 0.91 respectively. Anti-Hib IgG≥0.15ug/ml, which is generally regarded as being a level of protection at any single time, was observed in the 97.5%(39/40) of mothers and 95%(38/40) of babies.
Conclusion
: These data represent the possibility of lower incidence of invasive Hib diseases in Korea as well as good antibody response which is enough to provide the congenital passive immunity against Hib invasion in babies after birth. The isotype of IgG2 seems to play an important role in the immune response to H influenzae type b infection.

Keywords :Hib, Passive immunity, Anti-PRP IgG, IgG subclass