Supporting diversity, equity, inclusion, and belonging to strengthen and position the veterinary profession for service, sustainability, excellence, and impact.

Advancing equality and equity in society is creating positive change, and the time has come to critically evaluate veterinary medicine, which, by all metrics, lacks diversity. To keep pace with increasingly diverse demographics and recent surges in pet ownership among all racial/ethnic groups, significant efforts to enhance diversity, equity, inclusion, and belonging (DEIB) must occur in veterinary colleges and the profession. Recruiting more underrepresented students, building pipelines for diverse faculty/staff, and creating inclusive, welcoming environments where all can thrive are critical steps toward enhancing DEIB within our organizations and profession. Our goal is to share experiences and lessons learned from our intentional commitment to strengthen DEIB, with the hope that our journey will be helpful to others. Increasing diversity in the veterinary profession will be facilitated through removing barriers, creating inclusive work environments where all people feel they belong, and ensuring fair and equitable hiring and personnel management practices. These steps should in turn improve access and quality of veterinary care, ensure we are more representative of the communities we serve, increase revenue, and preserve the human-animal bond. "You cannot change any society unless you take responsibility for it, unless you see yourself belonging to it, and responsible for changing it." - Grace Lee Boggs.

Parasitemia due to Sarcocystis neurona-like infection in a clinically ill domestic cat.

An 8-year-old, 6-kg, male neutered Domestic Shorthair cat was presented to The Ohio State University Veterinary Medical Center (OSU-VMC) for difficulty breathing. Physical examination and thoracic radiographs indicated pneumonia, a soft-tissue mass in the left caudal lung lobe, and diffuse pleural effusion. The effusion was classified as modified transudate. Rare extracellular elongated (~5-7 µm × 1-2 µm) zoites with a central round to oval-shaped purple to deep purple vesicular nucleus with coarsely stippled chromatin and light blue cytoplasm were seen on a peripheral blood smear. Serum IgG and IgM were positive for Sarcocystis sp. antibodies and negative for Toxoplasma gondii antibodies, suggesting that the infection was acute rather than a recrudescence of prior infection. This organism was most consistent with either Sarcocystis neurona or Sarcocystis dasypi based on DNA sequence analysis of PCR products using COC ssRNA, ITS-1, snSAG2, and JNB25/JD396 primer sets. This is the first report to visualize by light microscopy circulating Sarcocystis sp. merozoites in the peripheral blood of a domestic cat. Therefore, Sarcocystis should be considered as a differential diagnosis in cats with suspected systemic protozoal infection.

Comparison of platelet function and viscoelastic test results between healthy dogs and dogs with naturally occurring chronic kidney disease.

OBJECTIVE To compare platelet function and viscoelastic test results between healthy dogs and dogs with chronic kidney disease (CKD) to assess whether dogs with CKD have platelet dysfunction and altered blood coagulation. ANIMALS 10 healthy control dogs and 11 dogs with naturally occurring CKD. PROCEDURES Blood and urine were collected once from each dog for a CBC, serum biochemical analysis, urinalysis, and determination of the urine protein-to-creatinine ratio, prothrombin time, activated partial thromboplastin time, plasma fibrinogen concentration, and antithrombin activity. Closure time was determined by use of a platelet function analyzer and a collagen-ADP platelet agonist. Thromboelastography (TEG) variables (reaction time, clotting time, α angle, maximum amplitude, and global clot strength [G value]) were determined by use of recalcified nonactivated TEG. Platelet expression of glycoprotein Ib (GPIb; receptor for von Willebrand factor), integrin αIIbß3 (αIIbß3; receptor for fibrinogen), and P-selectin (marker for platelet activation) was assessed by flow cytometry. RESULTS Compared with healthy control dogs, the median closure time was prolonged, the median maximum amplitude and G value were increased, and the median clotting time was decreased for dogs with CKD. Platelet expression of both αIIbß3 and P-selectin was also significantly increased for dogs with CKD, compared with that for control dogs. Platelet expression of GPIb, αIIbß3, and P-selectin was not correlated with closure time or any TEG variable. CONCLUSIONS AND CLINICAL RELEVANCE Results indicated that dogs with CKD frequently had evidence of platelet dysfunction and hypercoagulability that were not totally attributable to alterations in platelet surface expression of GPIb, αIIbß3, and P-selectin.

Making Sense of Lymphoma Diagnostics in Small Animal Patients.

This article summarizes and compares the various assays available to aid in the diagnosis and characterization of lymphoma in small animal patients. These techniques include cytology, histopathology, immunocytochemistry and immunohistochemistry, immunophenotyping by flow cytometry, and polymerase chain reaction for clonal antigen receptor gene rearrangement.

Osseous metaplasia within a canine insulinoma.

An 11-year-old male castrated mixed-breed dog was presented for exercise intolerance, tetraparesis, and persistent hypoglycemia. Abdominal ultrasound examination revealed 2 nodules within the right limb of the pancreas. Cytology from one nodule was consistent with a carcinoma of neuroendocrine origin, with a primary differential diagnosis of insulinoma. Histologic evaluation and immunohistochemistry for synaptophysin and insulin confirmed the diagnosis of insulinoma. Additionally, there was a solitary nodule of mineralized compact bone composing approximately 60% of the mass. To the authors' knowledge, this is the first report of osseous metaplasia within an insulinoma (islet cell carcinoma).

Making sense of lymphoma diagnostics in small animal patients.

This article summarizes and compares the various assays available to aid in the diagnosis and characterization of lymphoma in small animal patients. These techniques include cytology, histopathology, immunocytochemistry and immunohistochemistry, immunophenotyping by flow cytometry, and polymerase chain reaction for clonal antigen receptor gene rearrangement.

Analysis and cytologic characterization of hemocytes from freshwater mussels (Quadrula sp.).

BACKGROUND: Freshwater mussels are among the most endangered taxa in North America and minimally invasive techniques to evaluate their health are needed. OBJECTIVE: The objective of this study was to develop a standardized approach for identifying and enumerating the cellular components of freshwater mussel hemolymph. METHODS: Hemocyte clumping, total hemocyte count, and hemocyte morphology were compared in untreated hemolymph or hemolymph treated with formalin, sodium citrate, sodium heparin, EDTA, water, or l-cysteine. Morphology was then used to categorize hemocytes and perform a 100-cell differential. RESULTS: Treatment with formalin or >25 mg/mL l-cysteine reduced hemocyte clumping, although only formalin significantly increased the total hemocyte count. However, formalin also induced crenation that impaired hemocyte identification. Both EDTA and sodium citrate-induced hemocyte degranulation while sodium citrate and >40 mg/mL l-cysteine-induced cell lysis. Hemocytes could be categorized into 2 groups of granulocytes (eosinophilic or basophilic) and 2 groups of agranulocytes (large or small) for performing a cytologic differential. The differential was not significantly altered by anticoagulant treatments providing cell morphology was adequate for obtaining a differential. Eosinophilic granulocytes predominated (59%) with fewer large agranulocytes (27%) and basophilic granulocytes (13%). Small agranulocytes comprised 2% of the total population. CONCLUSIONS: No single treatment provided an optimal method to evaluate freshwater mussel hemolymph. Maximal hemocyte counts were obtained following formalin treatment. l-cysteine reduced clumping and maintained hemocyte morphology for performing a cytologic differential. These techniques provide a standardized approach for the hematologic evaluation of freshwater mussels.

Cervical thymoma originating in ectopic thymic tissue in a cat.

An 11-year-old female spayed domestic shorthair cat was referred to The Ohio State University Veterinary Teaching Hospital (OSU-VTH) for evaluation of a 6 x 4 x 3.5 cm mass in the left midcervical region causing increased respiratory sounds and lateral deviation of the trachea. A fine needle aspirate of the mass was obtained before referral and the cytology results were compatible with a reactive lymph node. Immunocytochemistry showed increased numbers of CD3+ T lymphocytes and small numbers of CD20+ and CD79a+ medium to large lymphocytes. Differential diagnoses from the referral pathologist were T-cell-rich B-cell lymphoma and feline Hodgkin's-like lymphoma. A subsequent fine needle aspirate performed at the OSU-VTH showed similar results. On flow cytometry the majority of cells were CD3+ T lymphocytes that were double positive for CD4 and CD8 (73%), compatible with either a double-positive (CD4+CD8+) T-cell lymphoma or lymphocytes from ectopic thymic tissue. The mass was surgically removed. Histopathology and immunohistochemistry of the mass revealed a predominant population of CD3+ small lymphocytes and small numbers of medium to large lymphocytes with moderate anisocytosis and anysokaryosis. A population of cytokeratin-positive epithelial cells surrounded small microcystic structures filled with eosinophilic material and structures interpreted as Hassall's corpuscles. These findings were consistent with thymic tissue and a diagnosis of ectopic thymoma was made. PCR results for lymphocyte antigen receptor rearrangement (PARR) were negative. The cat had no evidence of disease 16 months after removal of the mass. To our knowledge this is the first report of an ectopic cervical thymoma in a cat. The clinical and diagnostic features of this unusual case will be useful in helping veterinarians and pathologists obtain a presurgical diagnosis and establish a prognosis for similar lesions.

IgM paraprotein interference with hemoglobin measurement using the CELL-DYN 3500.

A 10-year-old male Labrador Retriever was presented for a 6-week history of polyuria, polydipsia, rear limb weakness, and ocular discharge. The dog had marked hyperproteinemia with an IgM monoclonal gammopathy, as determined by serum protein electrophoresis and immunoelectrophoresis. Cytologic findings in a lymph node aspirate were suggestive for lymphoma, which was confirmed and identified as B cell lineage by immunophenotyping and PCR antigen receptor rearrangement. In the CBC results, marked discrepancy was observed in the hemoglobin (HGB) concentration and MCHC obtained on a CELL-DYN 3500 analyzer (HGB 13.3 g/dL, MCHC 61.4 g/dL) as compared with an IDEXX LaserCyte analyzer (HGB 7.0 g/dL, MCHC 39.2 g/dL). To investigate this discrepancy, plasma was removed from an EDTA-anticoagulated blood sample from the patient, replaced with an equal volume of CELL-DYN diluent, and analyzed on the CELL-DYN. The resulting HGB (6.72 g/dL) and MCHC (33.5 g/dL) results were similar to those obtained initially on the LaserCyte. We concluded that precipitation of IgM paraprotein by the CELL-DYN lyzing reagent, which contains quaternary ammonium salts, falsely increased the spectrophotometric measurement of HGB on the CELL-DYN. The high MCHC was attributed to the false increase in HGB concentration. No interference with HGB measurement occurred with the LaserCyte, which uses a hypotonic solution to lyse RBCs before HGB determination. Paraprotein interference should be considered in veterinary patients with monoclonal gammopathy and unexpectedly high HGB and MCHC values.

Mucosal challenge with cell-associated or cell-free feline immunodeficiency virus induces rapid and distinctly different patterns of phenotypic change in the mucosal and systemic immune systems.

The majority of human immunodeficiency virus type 1 (HIV-1) infections occur via mucosal transmission through contact with genital secretions containing cell-associated and cell-free virus. However, few studies have assessed whether exposure to cells, HIV-1 infected or uninfected, plays a role in the sexual transmission of HIV-1. This study examined phenotypic changes in mucosal and systemic lymphoid tissue 24 hr after vaginal exposure to in vitro equilibrated infectious doses of cell-associated or cell-free feline immunodeficiency virus, uninfected heterologous cells, or medium alone. We found that even at this early time-point, mucosal exposure to virus induced substantial alterations in the phenotype and distribution of leucocytes, particularly in the tissues of the mucosal immune system. Second, we found that the type of virus inoculum directly influenced the phenotypic changes seen. Vaginal exposure to cell-free virus tended to induce more generalized phenotypic changes, typically in the peripheral immune system (blood and systemic lymph nodes). In contrast, exposure to cell-associated virus was primarily associated with phenotypic shifts in the mucosal immune system (gut and mucosal/draining lymph nodes). In addition, we found that exposure to uninfected heterologous cells also induced alterations in the mucosal immune system. These data suggest that significant immune changes occur within the first 24 hr of virus exposure, well before substantial replication would be anticipated. As the mucosal immune system, and particularly the gut, is an early and persistent target for lentiviral replication, these findings have substantial implications for HIV-1 pathogenesis and vaccine development.

FIV infection induces unique changes in phenotype and cellularity in the medial iliac lymph node and intestinal IEL.

Studies of human immunodeficiency virus-1 (HIV-1)-infected patients and simian immunodeficiency virus (SIV)-infected macaques have identified profound depletion of CD4(+) T cells and expansion of CD8(+) T cells in the gastrointestinal lamina propria. Less attention has been given to CD8(+) intraepithelial lymphocytes (IEL), and no studies have concurrently examined inductive sites such as draining lymph nodes. Our preliminary data in the feline immunodeficiency virus (FIV) animal model suggested additional changes in IEL, and marked differences in the responses of lymph nodes draining different mucosal sites. To address this, we quantified the absolute leukocyte yield and examined the phenotype of cells from small intestinal IEL, mesenteric lymph node (MLN), and medial iliac lymph node (ILN) from chronically FIV-infected cats. The cellularity of the ILN was increased 530% in FIV-infected animals with an expansion of CD62L(+) cells, suggesting an increased population of naive T cells. The number of CD4(+), as well as CD8(+), T cells was increased in the ILN, resulting in a CD4:CD8 ratio greater than 1:1. In contrast, reduced cellularity, specific loss of CD4(+) T cells, and inversion of the CD4:CD8 ratio was observed in the MLN, which drains the intestine. In IEL, loss of CD8alpha, CD8beta, and CD4-expressing T cells was found in FIV-infected cats. Furthermore, expression intensity of CD8alpha and CD5, markers known to be important in T cell function, was markedly decreased on IEL. These findings expand the array of immune alterations induced by lentiviral infection and indicate that characterization of multiple mucosal sites will be necessary to fully understand the pathogenesis of HIV-1 infection.

A novel canine lymphoma cell line: a translational and comparative model for lymphoma research.

A novel canine lymphoma cell line, OSW, was established from the malignant pleural effusion of a dog with peripheral T-cell lymphoma. The immunoprofile as determined by flow cytometry was as follows: positive for CD45, CD49d, CD18, CD11a; weakly positive for CD11b, CD11c, CD11d; and negative for CD45RA, CD1a, CD1c, CD3, TCRalphabeta, TCRgammadelta, CD4, CD5, CD8a, CD8b, CD90(Thy1), CD21, MHCII, CD14(TUK4), CD34, and MPO. Immunocytochemistry of cytospin preparations was negative for cytoplasmic CD3, CD79a, and MPO, but was positive for CD20. The cell line had an oligoclonal T-cell receptor gamma (TCRgamma) gene rearrangement. Array comparative genomic hybridization (aCGH) and single locus probe (SLP) analysis showed that there were copy number increases of loci on dog chromosome 13 (CFA 13), and copy number decreases were evident for regions of CFA 11, 22, 26, 30 and 32, which include several of the more common chromosomal aberrations reported previously in canine lymphoma. The OSW cell line grows rapidly in vitro and is tumorigenic as a xenograft in SCID/NOD mice. OSW represents one of only a few reported canine lymphoma cell lines and is the most thoroughly characterized. This cell line and xenograft represent significant in vitro and in vivo models, respectively, for comparative and translational lymphoma research.

Mucosal administration of low-dose cell-associated feline immunodeficiency virus promotes viral latency.

Human immunodeficiency virus type 1 can occasionally be detected as a cryptic or latent infection in seronegative, asymptomatic patients. To develop an animal model of host latency, cats were mucosally challenged with 10(2)-10(6) feline immunodeficiency virus (FIV)-infected T cells. Although high-dose exposure (10(4)-10(6) T cells) resulted in progressive infection, no evidence of infection was seen in 5 of 6 cats exposed to 10(2) or 10(3) T cells. However, after ex vivo CD8(+) T cell depletion and phorbol myristate acetate treatment, FIV could be reactivated in tissues from 4 cats. Thus, latent tissue viral reservoirs can be induced by low-dose cell-associated mucosal challenge, providing a model to dissect the mechanisms that control reservoir establishment.

IgG from acutely infected cats blocks mucosal feline immunodeficiency virus infection.

We have previously shown an absence of detectable systemic or local infection in cats exposed to an infectious (100 TCID(50)) feline immunodeficiency virus (FIV) plasma inoculum via either the rectal or vaginal mucosa. In contrast, this same plasma inoculum was infectious via parenteral inoculation. Moreover an equivalent dose of cell-free tissue culture-origin virus inoculum infected 100% of cats by either the rectal or vaginal exposure route. To evaluate this phenomena, we used a tissue culture system to identify a heat-stable factor in the plasma of cats acutely (3 weeks) infected with FIV that blocked infection of naive peripheral blood mononuclear cells (PBMC) by either cell-free or cell-associated FIV in vitro. A single application of as little as a 1:200 dilution of either heparinized or Alsevier's anticoagulated plasma effectively inhibited production of FIV p26 in culture over a 21-day co-culture period. Depletion of antibody using a protein A column abrogated the inhibitory effect of FIV plasma against in vitro FIV infection. Co-inoculation of heat-inactivated plasma with 400 TCID(50) FIV-B-2542 cell-free supernatant virus onto the vaginal mucosa of two cats resulted in complete inhibition of infection in one cat and increased time to infection in the second. Thus, antibody found in the plasma of cats acutely infected with FIV blocks cell-associated and cell-free infection, inhibits virus production in previously infected cells, and reduces mucosal transmission efficiency in vivo. Extrapolation may help explain the relatively inefficient mucosal transmission of human immunodeficiency virus-1 (HIV) and other lentiviruses.

Induction of serum and mucosal FIV-specific immune responses by intranasal immunization with p24Gag.

We examined the ability of FIV p24Gag to induce systemic and mucosal FIV-specific immune responses when delivered as a nasal immunogen alone, or with a mucosal adjuvant, Escherichia coli heat labile toxin LT(R192G). Nasal immunization with p24Gag alone induced FIV-specific immune responses but overall responses were weak, transient, and/or present only in a few animals. Co-administration of LT(R192G) resulted in strong FIV-specific serum IgG and enhanced salivary IgA responses. Moreover, FIV-specific IgA was detected in vaginal wash fluid from 6/6 cats co-immunized with LT(R192G) and p24Gag versus 1/6 immunized with p24Gag alone. This is the first report detailing induction of systemic or mucosal FIV-specific immune responses by nasal immunization alone. As such, this study demonstrates that nasal immunization of cats can be a relevant and effective route for the delivery of candidate vaccines. However, while nasal immunization of cats with p24Gag induces antigen-specific systemic immune responses, development of strong systemic and mucosal immune responses requires co-administration of a mucosal adjuvant, such as LT(R192G).

Artifactual hypoglycemia associated with hemotrophic mycoplasma infection in a lamb.

BACKGROUND: A 35-day-old male lamb with Mycoplasma ovis infection (previously Eperythrozoon ovis) was evaluated because of severe hypoglycemia (serum glucose 4 mg/dL, Hitachi 704 automated chemistry analyzer) inconsistent with the animal's condition. Whole blood glucose concentration measured with a glucometer was 74 mg/dL. OBJECTIVE: The purpose of this study was to investigate this discrepancy through in vitro evaluation of the patient's blood. METHODS: Blood was incubated alone, with increasing concentrations of plasma, or with equine serum of known glucose concentration for 0, 15, 30, and 60 minutes at room temperature; end-point glucose concentrations were compared with blood from a control sheep handled similarly. RESULTS: A rapid decline in glucose concentration was observed in heparinized or EDTA anticoagulated whole blood from the infected lamb incubated alone or with the equine serum. Glucose concentrations in incubated samples from a control sheep remained stable. Incubation of increasing concentrations of heparinized blood with autologous plasma resulted in decreased glucose concentrations in patient, but not control, blood. As parasitemia decreased after treatment, serum glucose concentration increased, serum lactate concentration decreased, and in vitro glucose concentration stabilized. CONCLUSIONS: These findings are consistent with parasite-associated in vitro glucose consumption. An increase in the lamb's plasma glucose concentration associated with reduction of parasite load suggested excess glucose consumption also may have occurred in vivo.

Assessment of CD4+ and CD8+ IFN-gamma producing cells by ELISPOT in naïve and FIV-infected cats.

IFN-gamma is critical for the development of antiviral cell-mediated immunity in HIV infected humans and FIV infected cats. The ELISPOT has proven to be a technically straightforward assay to quantify the number of IFN-gamma producing cells and offers a reasonable alternative for the quantitative measurement of T-cell function in cats. We used a feline-specific ELISPOT to identify constitutive as well as Con A stimulated IFN-gamma production in T-cell subsets and determine if there were differences between purified (positively sorted) and negatively depleted populations from naïve and FIV infected cats. We found no difference in the total number of PBMC constitutively producing IFN-gamma in naïve and FIV+ cats. Con A exposure was associated with increased numbers of IFN-gamma producing PBMC in naïve, but not FIV+, cats. Equivalent numbers of CD4+ and CD8+ T cells constitutively expressed IFN-gamma in naïve cats. However, in FIV+ cats, the number of IFN-gamma producing CD8+ T-cells was approximately two-fold over that seen for CD4+ T-cells. We found minimal differences between purified (e.g. CD4+ or CD8+) and corresponding depleted (e.g. CD8- or CD4-) populations in samples from FIV+ cats. In contrast, depleted populations from naïve cats showed greater response to Con A than did purified populations. Thus, while determination of the number of IFN-gamma producing cells by feline-specific ELISPOT is a useful tool for the evaluation of the feline immune response, determination of the initial sample population and T-cell subset is critical for optimal interpretation of the IFN-gamma ELISPOT.