Formation and glomerular deposition of immune complexes in mice administered bovine serum albumin: Evaluation of dose, frequency, and biomarkers

Abstract

In preclinical toxicity studies, species-foreign proteins administered to animals frequently leads to formation of anti-drug antibodies (ADA). Such antibodies may form circulating immune complexes (CIC) with the administered protein. These CIC can activate the classical complement pathway, thereby forming complement-bound CIC (cCIC); if large of amounts of CIC or cCIC is formed, the clearance mechanism may become saturated which potentially leads to vascular immune complex (IC) deposition and inflammation. Limited information is available on the effect of different treatment related procedures as well as biomarkers of IC-related vascular disease. In order to explore the effect of different dose regimens on IC formation and deposition, and identification of possible biomarkers of IC deposition and IC-related pathological changes, C57BL/6J and BALB/c mice were dosed subcutaneously twice weekly with bovine serum albumin (BSA) for 13 weeks without adjuvant. After 6 and 13 weeks, CIC and cCIC were detected in plasma; after 13 weeks, IC deposition was detected in kidney glomeruli. In particular immunohistochemistry double-staining was shown to be useful for detection of IC deposition. Increasing dosing frequency or changing BSA dose level on top of an already established CIC and cCIC response did not cause changes in IC deposition, but CIC and cCIC concentrations tended to decrease with increased dose level, and increased cCIC formation was observed after more frequent dosing. The presence of CIC in plasma was associated with glomerular IC deposits in the dose regimen study; however, the use of CIC or cCIC as potential biomarkers for IC deposition and IC-related pathological changes, needs to be explored further.

Formation and Glomerular Deposition of Immune Complexes in Mice Administered Human Antibodies: Evaluation of Dose, Frequency, and Biomarkers

“…The ADA, CIC, and cCIC response were established at week 6 in C57BL/6J mice administered with aTNFa, also suggested previously in similar studies with BSA, 22 whereas the cCIC response of BALB/c mice in the present study was slightly increased over time. Moreover, a difference between the immune response in the 2 inbred mouse stains was observed.…”

“…Samples from the present studies were partly used for qualification and characterization of the immune assays 20,21 and vehicle animals partly described in a previous publication. 22…”

“…Immunohistochemistry slides were evaluated by light microscopy in a blinded manner for IC deposits in kidney glomeruli, as described previously. 22 An IHC score 0 to 3 was given for the degree of granular staining within the glomerular tuft (0, no granular staining; 1, mild; 2, moderate; 3, severe; Figure 1) if at least 3 glomeruli in a slide were affected and a score of 0 to 3 was given for frequency of affected glomeruli within the kidney (0, none; 1, up to 20%; 2, 20-50%; 3, 50-100%; Table 1). Each kidney was for each staining assigned a total IHC score by adding the score for the degree of granular staining within glomerular tufts to the score for frequency of affected glomeruli in the kidney, and the animal was assigned the score from the kidney with the highest IHC score.…”

“…Double IHC staining was used to detect colocalization of granular staining containing hIgG and C3d or mIgM and C3d in mouse kidney tissue on selected animals from dose regimen study administered with vehicle or aTNFa. The IHC procedure and the primary antibodies were, as described, 22 except for the following minor changes. The primary antibody goat anti-C3d (R&D Systems; diluted 1:100 in TBS) was co-incubated with either biotinylated donkey anti-mIgM (Jackson Immunoresearch; diluted 1:2000 in TBS) or biotinylated donkey anti-hIgG (diluted 1:100 in TBS).…”

Evaluation of breast cancer regarding molecular and immunochemical markers

“…This hypothesis achieved by comparing the RAPD profi les obtained from healthy and malignant cells within the same person. Hence, the potential effects of study in human genetic variability have been addressed these argument questions among species [20,21]. In longitudinal studies of chemical or physical agents interaction with the genomic DNA may also be responsible for the DNA alterations.…”