TY - JOUR
T1 - Comparison of Complement Activity in Adult and Preterm Sheep Serum
AU - Ahmed, S.
AU - Kemp, Matthew
AU - Payne, Matt
AU - Kallapur, Suhas
AU - Stock, S.J.
AU - Marsh, H.C.
AU - Jobe, Alan
AU - Newnham, John
AU - Spiller, O.B.
PY - 2015/3
Y1 - 2015/3
N2 - © 2014 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd. Problem: Functional complement activity is routinely measured utilizing rabbit antibody-sensitized sheep erythrocytes. Due to complement inhibitor expression on erythrocytes, the development of an alternative method to measure complement function in sheep serum was required. Method of study: Several species of target erythrocyte and sensitizing antibody were investigated for improved measurement of complement function testing. Results and conclusion: Guinea pig erythrocytes were identified as the optimal target, although sensitizing them with rabbit antiguinea pig erythrocyte antibody did not enhance the lysis by maternal sheep serum. In contrast, preterm neonatal sheep serum was unable to efficiently lyse guinea pig erythrocytes unless pre-sensitized with antibody. Further investigation revealed that maternal serum contained high levels of antibodies that cross-reacted with guinea pig and rabbit erythrocytes, while no cross-reacting antierythrocyte antibodies were found in preterm neonatal serum. Therefore, unlike primates, rabbits, and guinea pigs, no transplacental transfer of maternal IgG to foetal sheep occurs. Use of exogenous complement regulators is often used to dissect the contribution of complement to disease pathogenesis; however, we found that while full-length soluble human complement receptor 1 (sCR1, CDX-1135) was able to inhibit lysis of guinea pig erythrocytes by human and rat serum, no inhibition of sheep serum could be observed. Investigation of complement contribution to disease pathogenesis in the future will require the identification of an inhibitor that is effective against sheep complement.
AB - © 2014 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd. Problem: Functional complement activity is routinely measured utilizing rabbit antibody-sensitized sheep erythrocytes. Due to complement inhibitor expression on erythrocytes, the development of an alternative method to measure complement function in sheep serum was required. Method of study: Several species of target erythrocyte and sensitizing antibody were investigated for improved measurement of complement function testing. Results and conclusion: Guinea pig erythrocytes were identified as the optimal target, although sensitizing them with rabbit antiguinea pig erythrocyte antibody did not enhance the lysis by maternal sheep serum. In contrast, preterm neonatal sheep serum was unable to efficiently lyse guinea pig erythrocytes unless pre-sensitized with antibody. Further investigation revealed that maternal serum contained high levels of antibodies that cross-reacted with guinea pig and rabbit erythrocytes, while no cross-reacting antierythrocyte antibodies were found in preterm neonatal serum. Therefore, unlike primates, rabbits, and guinea pigs, no transplacental transfer of maternal IgG to foetal sheep occurs. Use of exogenous complement regulators is often used to dissect the contribution of complement to disease pathogenesis; however, we found that while full-length soluble human complement receptor 1 (sCR1, CDX-1135) was able to inhibit lysis of guinea pig erythrocytes by human and rat serum, no inhibition of sheep serum could be observed. Investigation of complement contribution to disease pathogenesis in the future will require the identification of an inhibitor that is effective against sheep complement.
U2 - 10.1111/aji.12299
DO - 10.1111/aji.12299
M3 - Article
C2 - 25046333
SN - 1046-7408
VL - 73
SP - 232
EP - 241
JO - American Journal of Reproductive Immunology
JF - American Journal of Reproductive Immunology
IS - 3
ER -
