Immune-Modulatory Effects of Mesenchymal Stromal Cell Infusions for the Treatment of Factor VIII Inhibitor in Hemophilia A.
Bibliographic record
Abstract
Abstract Abstract 1299 Poster Board I-321 The current most serious treatment-related complication in hemophilia A is the development of antibodies to FVIII following exposure to FVIII replacement therapy. We have previously demonstrated that the injection of syngeneic mesenchymal stromal cells (MSCs) into hemophilia A mice with FVIII antibodies lead to a robust decrease in FVIII specific IgG levels because the secretome of MSCs suppresses plasma cell immunoglobulin production, induces plasmablast proliferation, and leads to IL-10-mediated blockade both in vitro and in vivo. Therefore, we wanted to pursue this study in a large animal model. In the current study, we harvested MSCs from bone marrow aspirates obtained from 2 hemophilia A dogs with both human and canine FVIII inhibitors. The isolated MSCs were expanded ex vivo for the infusions. Prior to the infusions, we performed in vitro characterization of the canine MSCs and found that the cells secrete a wide range of cytokines and chemokines including CC chemokine ligand 2 (CCL2) and CCL2 that has been cleaved to its truncated inhibitory form by proteolysis with matrix metalloproteinases (MMPs). These results are identical to those seen in the previous mouse experiments. Before the MSC infusions, the hemophilia A dogs with inhibitors were immunized by multiple intravenous infusions of both human FVIII and canine cryoprecipitate to further boost the development of FVIII antibodies. Expanded autologus MSCs (4.5-6.0×106 cells/Kg) were infused intravenously into the first dog twice, with a month in between each injection. After the second infusion, the titer of anti-human FVIII inhibitory activity was significantly decreased from 6.2 to 1.9 BUs and a transient but significant decrease from 3.5 to 2.2 BUs against canine FVIII. Second MSC infusion trial is currently ongoing in a second dog. In parallel with in vivo study, the inhibitory response mediated by MSCs on the FVIII antibody producing B cells was assessed by ELISPOT assay. In conclusion, MSCs may play an immunosuppressive role in modulating Immunoglobulin production by plasma cells via MMP processing of paracrine CCL2 secretion. This may represent a novel cellular therapy for attenuation of pathological humoral responses such as anti-FVIII antibody development. Disclosures No relevant conflicts of interest to declare.
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How this classification was reachedexpand
Full frame machine prediction
Teacher imitationNot calibrated prevalence, not ground truth. Human validation pending. The Gemma side is a direct model label for every work in the frame, read from the title-only record. The Codex side is a classifier learned from the 10,348 direct Codex labels and calibrated to design-weighted sample rates; fields without enough sample support carry no Codex call. Candidate is the union of the two sides; consensus is their intersection. These outputs are machine_predicted_unvalidated and are not human labels.
Distilled classifier scores by category (both heads)
| Category | Codex | Gemma |
|---|---|---|
| Metaresearch | 0.000 | 0.000 |
| Meta-epidemiology (narrow) | 0.000 | 0.000 |
| Meta-epidemiology (broad) | 0.000 | 0.000 |
| Bibliometrics | 0.000 | 0.000 |
| Science and technology studies | 0.000 | 0.000 |
| Scholarly communication | 0.000 | 0.000 |
| Open science | 0.000 | 0.000 |
| Research integrity | 0.000 | 0.000 |
| Insufficient payload (model declined to judge) | 0.001 | 0.000 |
Machine scores (provisional)
The two teacher heads of the student model, read on this work. A score orders the frame for review; it never asserts a category, and the validation status ships verbatim with every row.
Baseline scores from an immature model (maturity gate not passed, 7 training rounds). Scores rank; they never assert a category.
score_only:v0-immature-baseline · verbatim from the scoring run: score_only means the number may rank works, and no category label ships from itClassification
machine, unvalidatedMachine predicted; a candidate call from one source (direct Gemma or distilled Codex), not a consensus.
How this classification was reached, model by model and score by score, is at the end of the page under "How this classification was reached".