Common variable immunodeficiency in horses is characterized by B cell depletion in primary and secondary lymphoid tissues.
BACKGROUND
Common variable immunodeficiency (CVID) in horse patients is characterized by late-onset B cell lymphopenia or depletion, hypo- or agammaglobulinemia, impaired humoral response to tetanus toxoid vaccination, and recurrent fevers and bacterial infections.


CONCLUSIONS
This study describes the clinical and immunologic findings of 14 affected horses (average age 10.7 +/- 4.4 years) of both genders (six females, eight males) and different breeds (eight Thoroughbreds, four Quarter Horses, one Warmblood, one Pony). Serial immunological testing in peripheral blood revealed persistent, severe B cell lymphopenia (mean 1.3 +/- 2.3% positive cells) in all patients. Serum IgG (range <200 to 800 mg/dL) and IgM (<or=25.0 mg/dL) deficiency was common to all horses. Serum IgA concentrations declined with time. Histopathology and immunohistochemistry revealed absence of lymphoid follicles and B cells in primary and secondary lymphoid tissues. CVID is a cause of recurrent pneumonia, septicemia, and meningitis in adult horses and has a grave prognosis for clinical management and survival.
Flaminio
M Julia B F
MJ
Department of Clinical Sciences, College of Veterinary Medicine, Cornell University, Ithaca, NY 14853, USA. mbf6@cornell.edu
Tallmadge
Rebecca L
RL
Salles-Gomes
Cristina O M
CO
Matychak
Mary Beth
MB
D000818:Animals; D001402:B-Lymphocytes / Q000276:immunology* / Q000378:metabolism / Q000473:pathology; D001853:Bone Marrow / Q000276:immunology / Q000378:metabolism / Q000473:pathology; D017074:Common Variable Immunodeficiency / Q000276:immunology / Q000473:pathology / Q000662:veterinary*; D005260:Female; D006734:Horse Diseases / Q000276:immunology* / Q000473:pathology; D006736:Horses; D007136:Immunoglobulins / Q000097:blood; D008198:Lymph Nodes / Q000276:immunology / Q000378:metabolism / Q000473:pathology; D008231:Lymphopenia / Q000276:immunology / Q000473:pathology / Q000662:veterinary*; D008297:Male; D013154:Spleen / Q000276:immunology / Q000378:metabolism / Q000473:pathology; D013601:T-Lymphocytes / Q000276:immunology* / Q000378:metabolism / Q000473:pathology
D007136:Immunoglobulins