+T-cell and auto-reactive antibody response against an autosomal antigen.
ABSTRACT
© F e r r a t a S t o r t i F o u n d a t i o nThis antibody response was mapped to a small nonpolymorphic region of the protein. In conclusion, this is the first report demonstrating induction of a coordinated allo-T cell and auto-B cell response against an autosomal antigen after alloSCT.
Methods
Hematopoietic samplesPeripheral blood and bone marrow samples were obtained from patients and healthy individuals after approval by the Leiden University Medical Center Institutional Review Board and informed consent according to the Declaration of Helsinki.
Antigen presentation assaysEBV-LCL were loaded with 1 mg/mL of synthetic peptides in IMDM with 2% FCS and incubated for 2 h at 37°C. Cells were washed twice and plated at 30,000 cells/well in a 96-well plate. Effector cells were added at 5000 T cells/well. After overnight coincubation, IFN-γ production was measured by ELISA (Sanquin, Burton upon Trent, UK) according to the manufacturer's instructions.
Helper function assaysTo induce maturation of dendritic cells (DC), CD4 + T-cell clones and immature DC were seeded in a 1:1 ratio in a 24-well plate. After four days of co-incubation, cells were harvested, washed and stained with antibodies for FACS analysis. For induction of B-cell activation, CD4 + T-cell clones and isolated B cells were seeded in a 1:1 ratio and after two days of co-incubation, cells were harvested, washed and stained for FACS analysis.
Western blot analysisWhole cell lysates of transfected HEK293T cells were obtained from OriGene (Rockville, USA). HeLa cells were retrovirally transduced with MP71 vector containing PTK2B or PI4K2B constructs; 20 mg of protein was loaded on each lane. SDS-Page was run on pre-cast NuPage® Novex 10% Bis-Tris Mini gels (Invitrogen) for 35 min at 30V under reducing conditions. Gels were blotted on PVDF membranes using XCell SureLock® Mini-Cell blotting system (Invitrogen) according to the manufacturer's instructions. Blots were blocked for 1 h at room temperature in phosphatebuffered saline with 0.05% Tween-20 and 5% BSA, and subsequently incubated with diluted (1:40) serum samples overnight at 4°C. Subsequently, the membrane was incubated with biotinylated anti-human IgG and streptavidin-QDots 625 (Invitrogen) for 1 h each and visualized under UV illumination.
Suspension bead arrayThe suspension bead array was performed as previously described. 20,21 Purified proteins (20 mg) were coupled to carboxylated beads (Bio-Rad Laboratories B.V.) according to the manufacturers' instructions. Diluted serum samples (1:100 and 1:300) were pre-absorbed with 0.5% (w/v) polyvinylalcohol and 0.8% (w/v) polyvinylpyrrolidone (Sigma) (PVX) and 1% bovine serum albumin (BSA) for 1 h prior to incubation with the protein-coupled bead mix at room temperature on a shaker for 1 h. In specific blocking experiments, serum samples were pre-absorbed with purified recombinant proteins at 0.5 or 2.0 mg/mL in PVX and 1% BSA. Beads were washed and incubated for another...