T-dependent antibody response TDAR

Whereas the experimental design is quite standardized regarding maternal aspects, the duration of postnatal infant assessments is rather variable between studies, for example, from 7 days to 720 days in our experience. Evidently there is a need for standardization of the timing and type of test batteries for infants and of the time period the infant should be raised. For behavioral tests, a postnatal observation period of 9 months appears essential since these tests can only by applied from the age of 6 months onward. For evaluation of immune system development, a period of 6 months appears mandatory since from that age onward blood volume is sufficient to conduct several tests, such as the T cell dependent antibody response (TDAR), NK cell... 

If the weight-of-evidence review indicates that additional immunotoxicity studies are needed, there are a number of assays which can be used. It is recommended that an immune function study be conducted, such as a T-cell dependent antibody response (TDAR). If specific cell types are affected in STS not involving cells participating in a TDAR, assays that measure... 

The objective of this section is to provide a description of several immune parameters and methodologies that are used in the preclinical setting to characterize immune hazards for human risk assessments. The utility of a standalone functional evaluation, specifically the rat T cell-dependent antibody response (TDAR) model developed for regulated immunotoxicity evaluations (Gore et al, 2004), is mainly used for hazard identification, i.e., unintended immunosuppression. This assay is based on an end point parameter that is the... 

NK natural killer CTL cytotoxicT lymphocyte TDAR T-dependent antibody response MCMV murine cytomegalovirus MZB cells marginal zone B cells TIAR T-independent antibody response. 

Evaluation of a T cell-dependent antibody response (TDAR) is a critical component of the evaluation of immune function in the neonates. In this assay, neonates are injected with a T-dependent antigen, usually keyhole hmpet hemocyanin (KLH) or tetanus toxoid ( ITX), and the development of antibodies is measured over time. In monkeys there can be high inter-animal variability so the collection of serial blood samples is important and the data can be expressed as the area under the antibody titer versus time curve. Figure... 

TDAR = T cell dependent antibody response, DTH (=delayed-type hypersensitivity test) is problematic in NHP. 

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