Ontology highlight
ABSTRACT:
Hypothesis: English bulldogs have a syndrome of nonneoplastic B-cell expansion.
Animals: Eighty-four English bulldogs with small-sized CD21+ B-cell lymphocytosis in the blood as determined by flow cytometry.
Methods: This is a retrospective study. We characterized this syndrome by assessing B-cell clonality, clinical presentation, flow cytometric features, and immunoglobulin gammopathy patterns. We identified 84 cases with CD21+ lymphocytosis among 195 English bulldogs with blood samples submitted to the Colorado State University-Clinical Immunology laboratory for immunophenotyping between 2010 and 2019. Flow cytometry features were compared to normal B-cells and BCLL cases. PCR for antigen receptor rearrangements (PARR) by multiple immunoglobulin primers was performed to assess B-cell clonality. A subset of cases with gammopathy were examined by protein electrophoresis, immunofixation, and immunoglobulin subclass ELISA quantification.
Results: Seventy percent (58/83) of cases had polyclonal or restricted polyclonal immunoglobulin gene rearrangements, suggesting nonmalignant B-cell expansion. The median age of all dogs in the study was 6.8?years and 74% were male. The median (range) lymphocyte count was 22?400/?L (2000-384?400/?L) and B-cells had low expression of class II MHC and CD25. Splenomegaly or splenic masses were detected in 57% (26/46) of cases and lymphadenopathy in 11% (7/61). Seventy-one percent (52/73) of cases had hyperglobulinemia and 77% (23/30) with globulin characterization had IgA?±?IgM polyclonal or restricted polyclonal gammopathy patterns.
Conclusions and clinical importance: Polyclonal B-cell lymphocytosis in English bulldogs is characterized by low B-cell class II MHC and CD25 expression, splenomegaly and hyperglobulinemia consisting of increased IgA?±?IgM. We hypothesize that this syndrome has a genetic basis.
SUBMITTER: Rout ED
PROVIDER: S-EPMC7694837 | biostudies-literature | 2020 Nov
REPOSITORIES: biostudies-literature
Journal of veterinary internal medicine 20201015 6
<h4>Background</h4>English bulldogs disproportionally develop an expansion of small B-cells, which has been interpreted as B-cell chronic lymphocytic leukemia (BCLL). However, clonality testing in these cases has often not been supportive of neoplasia.<h4>Hypothesis</h4>English bulldogs have a syndrome of nonneoplastic B-cell expansion.<h4>Animals</h4>Eighty-four English bulldogs with small-sized CD21+ B-cell lymphocytosis in the blood as determined by flow cytometry.<h4>Methods</h4>This is a re ...[more]