Tao Wei; Wei-Hong Lv; Mei-Hua Gao; Shan-Juan Tan; Ling Li; Lei Zhang
Abstract
Background: The extent to which maternal antibodies against the hepatitis B surface antigen (HBsAb) acquired transplacentally affect the immune responses to the hepatitis B vaccine (HBVac) in infants is still uncertain.Objective: To explore the impact of the HBsAb on the immune response to the HBVac ...
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Background: The extent to which maternal antibodies against the hepatitis B surface antigen (HBsAb) acquired transplacentally affect the immune responses to the hepatitis B vaccine (HBVac) in infants is still uncertain.Objective: To explore the impact of the HBsAb on the immune response to the HBVac in a mouse model.Methods: According to the doses of the HBVac (2, 5 μg) injected, 267 BALB/c mice were divided into two groups. Each group was subdivided into 3 subgroups based on the doses of the hepatitis B immunoglobulin (HBIG) (0, 25, 50 IU) administered. The HBsAb titers were detected 4 weeks after completing the HepB vaccination. Results: Among all the mice, 40 had an HBsAb titer <100 mIU/mL (non- or low-response to the HBVac). The rates of the HBsAb titer <100 mIU/mL in 0, 25 and 50 IU HBIG groups were 1.1%, 23.1%, and 20.7%, respectively. Multivariate logistic regression analysis showed that the risk factors for low- or non-response to the HBVac were injection with the HBIG, low HBVac dose, and hypodermic injection. The mean HBsAb titers (log10) reduced gradually in the 0, 25 and 50 IU HBIG groups (P<0.001).Conclusion: The HBIG administration has negative impacts on the peak level of the HBsAb and the rate of an effective immune response. This implies that the maternal HBsAb acquired transplacentally might inhibit the immune responses to the HBVac in infants.
Arash Mahboubi; Mohammad Reza Fazeli; Rasoul Dinavand; Nasrin Samadi; Mohammad Sharifzadeh; Houshmand Ilka; Saeed Azadi; Hassan Kalkouei; Rasoul Hajikhanmirzaei; Mahboubeh Valadkhani
Volume 5, Issue 3 , September 2008, , Pages 163-170
Abstract
Background: Several adjuvants have been evaluated for vaccine formulations but alu-minum salts will continue to be used for many years due to their safety, low cost and adjuvanticity with different antigens. Two commonly used aluminum adjuvants, alumi-num hydroxide and aluminum phosphate have different ...
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Background: Several adjuvants have been evaluated for vaccine formulations but alu-minum salts will continue to be used for many years due to their safety, low cost and adjuvanticity with different antigens. Two commonly used aluminum adjuvants, alumi-num hydroxide and aluminum phosphate have different adjuvanticity properties. Com-mercial recombinant protein hepatitis B vaccines containing aluminum hydroxide is fac-ing low induction of immunity in some sections of the vaccinated population. Objec-tive: In this study, to follow the current global efforts in finding more potent hepatitis B vaccine formulations, adjuvanticity of aluminum phosphate, aluminum hydroxide and their combinations has been evaluated. Methods: The formulated vaccines were admin-istered intra-peritoneally (i.p.) to BALB/c mice and the titer of antibody was determined after 28 days using ELISA technique. The geometric mean of antibody titer (GMT, mIU/ml), seroconversion and seroprotection rates, ED50 (ng) and relative potency (μg/dose) of different formulations were determined. Results: GMT of antibody titer, seroconversion and seroprotection rates showed significantly higher adjuvanticity for aluminum phosphate than other formulations. The ED50 of aluminum phosphate was approximately two fold less than other formulations. Conclusion: Aluminum phosphate showed more adjuvanticity than aluminum hydroxide and their combinations in hepati-tis B protein vaccine. The use of aluminum phosphate as adjuvant leads to higher im-munity which may result in more protective response in vaccinated groups.