Bridget C. Garner

Characteristics of canine platelet-rich plasma prepared with five commercially available systems

OBJECTIVE To characterize platelet-rich plasma (PRP) products obtained from canine blood by use of a variety of commercially available devices. SAMPLE Blood samples from 15 dogs between 18 months and 9 years of age with no concurrent disease, except for osteoarthritis in some dogs. PROCEDURES PRP products were produced from blood obtained from each of the 15 dogs by use of each of 5 commercially available PRP-concentrating systems. Complete blood counts were performed on each whole blood sample and PRP product. The degree of platelet, leukocyte, and erythrocyte concentration or reduction for PRP, compared with results for the whole blood sample, was quantified for each dog and summarized for each concentrating system. RESULTS The various PRP-concentrating systems differed substantially in the amount of blood processed, method of PRP preparation, amount of PRP produced, and platelet, leukocyte, and erythrocyte concentrations or reductions for PRP relative to results for whole blood. CONCLUSIONS AND CLINICAL RELEVANCE The characteristics of PRP products differed considerably. Investigators evaluating the efficacy of PRPs need to specify the characteristics of the product they are assessing. Clinicians should be aware of the data (or lack of data) supporting use of a particular PRP for a specific medical condition.

Domestic dog health worsens with socio-economic deprivation of their home communities.

Dogs play an important role in infectious disease transmission as reservoir hosts of many zoonotic and wildlife pathogens. Nevertheless, unlike wildlife species involved in the life cycle of pathogens, whose health status might be a direct reflection of their fitness and competitive abilities, dog health condition could be sensitive to socio-economic factors impacting the well-being of their owners. Here, we compare several dog health indicators in three rural communities of Panama with different degrees of socio-economic deprivation. From a total of 78 individuals, we collected blood and fecal samples, and assessed their body condition. With the blood samples, we performed routine hematologic evaluation (complete blood counts) and measured cytokine levels (Interferon-γ and Interleukin-10) through enzyme-linked immunosorbent assays. With the fecal samples we diagnosed helminthiases. Dogs were also serologically tested for exposure to Trypanosoma cruzi and canine distemper virus, and molecular tests were done to assess T. cruzi infection status. We found significant differences between dog health measurements, pathogen prevalence, parasite richness, and economic status of the human communities where the dogs lived. We found dogs that were less healthy, more likely to be infected with zoonotic pathogens, and more likely to be seropositive to canine distemper virus in the communities with lower economic status. This study concludes that isolated communities of lower economic status in Panama may have less healthy dogs that could become major reservoirs in the transmission of diseases to humans and sympatric wildlife.

Identification of Synovial Fluid Biomarkers for Knee Osteoarthritis and Correlation with Radiographic Assessment.

Osteoarthritis (OA) is a costly and debilitating condition that is typically not diagnosed early enough to prevent progression of disease. The purpose of this study was to evaluate synovial fluid from knees with and without OA for potential markers of joint inflammation and degradation and to correlate these findings with radiographic severity of disease. With Institutional Review Board approval, synovial fluid samples were collected before the patient undergoing total knee arthroplasty. Control knees (n = 3) were patients younger than 30 years of age with no history of anterior cruciate ligament, posterior cruciate ligament, or meniscal injury, and no surgical history for either knee. Weight-bearing, anterior-posterior radiographic views were used to determine radiographic OA severity using the modified Kellgren and Lawrence scale. Synovial fluid samples from 18 patients (21 knees) were analyzed using a multiplex assay. Matrix metalloproteinase (MMP)-1 (p < 0.001), interleukin (IL)-6 (p < 0.013), IL-8 (p < 0.024), and Chemokine (C-C motif) ligand 5 (CCL5) (p < 0.006) were significantly higher in the synovial fluid of OA patients compared with normal patients. The radiographic score was significantly higher in patients with OA compared with normal knees (p < 0.002). MMP-1 had a moderate positive correlation with MMP-2, IL-6, IL-8, and CCL5. IL-6 had a strong positive correlation with IL-8 and a moderate positive correlation with MMP-2. Monocyte chemotactic protein 1 had a moderate positive correlation with IL-6 and a strong positive correlation with IL-8. Radiographic scores had a strong positive correlation with IL-6 and IL-8 and a moderate positive correlation with MCP-1. These data provide novel and clinically relevant information for the investigation of synovial fluid biomarkers for knee OA.

Expression of proteins in serum, synovial fluid, synovial membrane, and articular cartilage samples obtained from dogs with stifle joint osteoarthritis secondary to cranial cruciate ligament disease and dogs without stifle joint arthritis

OBJECTIVE To identify proteins with differential expression between healthy dogs and dogs with stifle joint osteoarthritis secondary to cranial cruciate ligament (CCL) disease. SAMPLE Serum and synovial fluid samples obtained from dogs with stifle joint osteoarthritis before (n = 10) and after (8) surgery and control dogs without osteoarthritis (9) and archived synovial membrane and articular cartilage samples obtained from dogs with stifle joint osteoarthritis (5) and dogs without arthritis (5). PROCEDURES Serum and synovial fluid samples were analyzed via liquid chromatography-tandem mass spectrometry; results were compared against a nonredundant protein database. Expression of complement component 3 in archived tissue samples was determined via immunohistochemical methods. RESULTS No proteins had significantly different expression between serum samples of control dogs versus those of dogs with stifle joint osteoarthritis. Eleven proteins (complement component 3 precursor, complement factor I precursor, apolipoprotein B-100 precursor, serum paraoxonase and arylesterase 1, zinc-alpha-2-glycoprotein precursor, serum amyloid A, transthyretin precursor, retinol-binding protein 4 precursor, alpha-2-macroglobulin precursor, angiotensinogen precursor, and fibronectin 1 isoform 1 preproprotein) had significantly different expression (> 2.0-fold) between synovial fluid samples obtained before surgery from dogs with stifle joint osteoarthritis versus those obtained from control dogs. Complement component 3 was strongly expressed in all (5/5) synovial membrane samples of dogs with stifle joint osteoarthritis and weakly expressed in 3 of 5 synovial membrane samples of dogs without stifle joint arthritis. CONCLUSIONS AND CLINICAL RELEVANCE Findings suggested that the complement system and proteins involved in lipid and cholesterol metabolism may have a role in stifle joint osteoarthritis, CCL disease, or both.

Systemic immune responses in Cytauxzoon felis-infected domestic cats

OBJECTIVE To characterize systemic immune responses in Cytauxzoon felis-infected cats. SAMPLE Blood and lung samples obtained from 27 cats. PROCEDURES Cats were allocated into 4 groups: cats that died of cytauxzoonosis, acutely ill C felis-infected cats, healthy survivors of C felis infection, and healthy uninfected cats. Serum concentrations of tumor necrosis factor-α and interleukin-1 β were measured and serum proteins characterized. Blood smears were stained immunocytochemically and used to assess immunoglobulin deposition. Immunohistochemical expression of CD18 and tumor necrosis factor-α were compared in lung tissues obtained from cats that died and healthy uninfected cats. A real-time reverse-transcription PCR assay for CD18 expression was performed on selected blood samples from all groups. RESULTS Concentrations of both cytokines were greater and serum albumin concentrations were significantly lower in cats that died of cytauxzoonosis, compared with results for all other groups. Erythrocytes from acutely ill cats and survivors of C felis infection had staining for plasmalemmal IgM, whereas erythrocytes from the other groups did not. Increased staining of C felis-infected monocytes and interstitial neutrophils for CD18 was detected. The real-time reverse-transcription PCR assay confirmed a relative increase in CD18 expression in cats that died of cytauxzoonosis and acutely ill cats, compared with expression in other groups. Immunostaining for TNF-α in lung samples confirmed a local proinflammatory response. CONCLUSIONS AND CLINICAL RELEVANCE Results indicated immunopathologic responses were greater in cats that died of C felis infection than in cats that survived C felis infection.

Influence of Cellular Composition and Exogenous Activation on Growth Factor and Cytokine Concentrations in Canine Platelet-Rich Plasmas

Objective The purposes of this study were to (1) evaluate correlations among platelet, leukocyte, growth factor, and cytokine concentrations in canine platelet-rich plasmas (PRPs) produced from five different canine PRP-concentrating systems and (2) compare the effects of different activation protocols on platelet activation and growth factor release from one of these PRPs. Methods PRP was made using blood from 15 dogs and each of 5 different PRP systems in a cross-over design. Complete blood counts were performed to quantify platelet and leukocyte concentrations. PRPs were activated, or not, according to manufacturer instructions, and transforming growth factor-β1 (TGF-β1), platelet-derived growth factor-BB (PDGF-BB), vascular endothelial growth factor, and tumor necrosis factor-alpha (TNF-α) were quantified. Differences among platelet, leukocyte, and growth factor concentration were compared among the different systems. Correlations between platelet and anabolic growth factor concentrations were assessed. Subsequently, PRP was made from 12 additional dogs using one of the devices. Each PRP was divided into three aliquots that were activated with calcium chloride (CaCl2), human γ-thrombin (HGT), or not activated. Expression of CD62P and platelet-bound fibrinogen (CAP1) was quantified for each activation group. Concentrations of TGF-β1, PDGF-BB, and TNF-α were also quantified for each activation group and a fourth group that was frozen/thawed. Differences among activation groups were assessed by a Friedman test. Results There were statistically significant differences among the PRPs made with difference devices with regard to platelet, leukocyte, TGF-β1, and PDGF-BB concentrations (p < 0.0001). There were weak to moderate correlations (R2 = 0.07–0.58) between platelet and anabolic growth factor concentrations but it appeared that activation had a greater effect on growth factor concentration than did cellular composition. Intentional platelet activation significantly increased CD62P and CAP1 expression as well as TGF-β1 and PDGF-BB concentrations in the one PRP in which all activation methods were assessed. Activation with HGT resulted in the greatest platelet activation, and CaCl2 and freeze/thaw elicited moderate increases in either growth factor release or CD62P and CAP1 expression. Conclusion There are positive correlations between platelet and anabolic growth factor concentrations in canine PRPs. However, intentional platelet activation has a greater effect on growth factor delivery than platelet concentration. Thrombin provides more robust activation than CaCl2.

Erythrocyte dysplasia in peripheral blood smears from 5 thrombocytopenic dogs treated with vincristine sulfate.

Secondary dyserythropoiesis has been associated with vincristine administration in dogs. Evaluation of bone marrow aspirates for the presence of morphologic abnormalities in the erythroid lineage aids in the diagnosis. However, morphologic features of circulating erythroid precursors in these cases have not been described previously. The purpose of this report was to describe the cytologic features of dyserythropoiesis in peripheral blood and also bone marrow smears in a case series of dogs with immune-mediated thrombocytopenia (IMT) treated with vincristine sulfate. Nineteen dogs receiving vincristine for treatment of IMT were identified by retrospectively searching a computerized medical record system. There were 5 dogs that had dysplastic erythroid precursors in peripheral blood smears within 7 days of vincristine treatment. Two of those 5 dogs also had evidence for erythrodysplasia in modified Wrights-stained bone marrow smears obtained postvincristine administration. Morphologic changes included bizarre or inappropriate mitotic figures, abnormal nuclear configurations (fragmentation, elongation, indentation, and binucleation), atypical nuclear remnants (Howell-Jolly bodies), or nuclear and cytoplasmic asynchrony within the erythroid precursors. A brief review of the literature with discussion of the etiologies for dyserythropoiesis is provided. The dyserythropoiesis was clinically insignificant in all 5 cases and resolved. However, pathologists and clinicians should be aware of these potential findings to prevent misdiagnosis of other conditions.

Eosinophilic leukemia in three African pygmy hedgehogs (Atelerix albiventris) and validation of Luna stain

Neoplasia is usually encountered in the African pygmy hedgehog at a mean age of 3.5 y, and malignancy is common. Myelogenous leukemias are rarely reported in hedgehogs. We describe 3 cases of eosinophilic leukemia in adult, middle-aged (mean age: 2.3 y) hedgehogs, for which prognosis appears grave. In 1 case, attempted treatment was unsuccessful, and in all 3 cases, the disease course was rapid and all died soon after diagnosis. Blood smear evaluation, along with complete blood count, was critical in making the diagnosis in all cases. Luna stain was validated and used to better visualize eosinophils in cytologic and histologic sections. Electron microscopy confirmed the presence of specific granules in hedgehog eosinophils.

Pathology of Haemonchus contortus in New World camelids in the southeastern United States a retrospective review

Most small ruminant farms in tropical climates are plagued by Haemonchus contortus, a hematophagous, abomasal parasite. Heavy burdens of this parasite can cause anemia, hypoproteinemia, weight loss, and mortality in susceptible animals. Haemonchus contortus is becoming a major health concern in New World camelids as well, namely llamas (Llama glama) and alpacas (Vicugna pacos), yet little research has been conducted regarding its prevalence or pathology in these species. Herein, we present a retrospective review of llamas and alpacas that were admitted to The University of Georgia Veterinary Teaching Hospital and Athens Diagnostic Laboratory between the years 2002 and 2013. Antemortem fecal egg count (FEC) estimates performed on 30 alpacas were negatively correlated with hematocrit, hemoglobin, and red blood cell count. Total protein was not significantly correlated with FEC. On postmortem examination, 55 of 198 camelids, including 2 from the aforementioned antemortem review, were infected with H. contortus, with llamas (42.6%) having a significantly higher infection rate than alpacas (22.2%). In 15.7% of the total cases, the parasite was the major cause of death. Common gross lesions included peritoneal, thoracic, and pericardial effusions, visceral pallor, subcutaneous edema, and serous atrophy of fat. Histologic lesions included centrilobular hepatic necrosis, hepatic atrophy, lymphoplasmacytic inflammation of the mucosa of the third gastric compartment (C3), extramedullary hematopoiesis in both the liver and spleen, and the presence of nematodes in C3. Our study emphasizes the importance of H. contortus diagnosis and herd monitoring in New World camelids, particularly llamas.

Morphologic, molecular, and ultrastructural characterization of a feline synovial cell sarcoma and derived cell line

A 2.5-year-old, male, neutered cat presented with a 5-month history of progressive right hind limb lameness and an enlarged right popliteal lymph node. Radiographs revealed significant bony lysis of the tarsus and distal tibia, and fine-needle aspirate of the bone lesion and lymph node revealed a neoplastic population of cells with uncertain origin. Amputation was elected, and the mass was submitted for histology and cellular culture for better characterization. Histologic examination revealed a mixture of spindle-shaped cells and larger, round to polygonal cells. All cells were immunoreactive for vimentin, and only the larger polygonal cells were also positive for cytokeratin. All cells were negative for desmin, smooth muscle actin, cluster of differentiation (CD)3, CD18, CD79a, macrophage antibody (MAC)387, and glial fibrillary acidic protein. Cultured neoplastic cells failed to express CD18, and were not able to secrete the pro-inflammatory cytokines tumor necrosis factor-α, interleukin-1 (IL-1)β, and IL-6 when stimulated by lipopolysaccharide, disproving that the cells originated from the macrophage or monocyte line. Ultrastructurally, neoplastic cells were characterized by abundant rough endoplasmic reticulum, interdigitating cellular processes, and membrane condensations. Based on location and cytologic, histologic, ultrastructural, and functional studies, this neoplasm was considered a synovial cell sarcoma.