An in vitro evaluation of storage media for the preservation of canine packed red blood cells

The effect of four different red blood cell storage media on in vitro parameters of stored canine red blood cells was studied. The storage media included citrate-phosphate-dextrose-adenine (CPDA-1), two additive solutions, and an additive solution modified by the addition of plasma. Biochemical and hematologic parameters, including red cell adenosine triphosphate (ATP); 2,3-diphosphoglycerate (2,3-DPG); pH; percent hemolysis; and supernatant sodium, potassium, and glucose were assessed immediately following preparation of the red cell concentrate and after 35 and 42 days of storage at 4 degrees C. All parameters changed significantly (p < 0.05) during storage. Significant differences due to effect of the storage media were also seen at each time period. After 35 days and 42 days of storage, CPDA-1 maintained the highest pH, potassium, and sodium values, and had the lowest 2,3-DPG, ATP (p=0.052), and glucose values. No differences were seen in hemolysis after 35 days of storage. No additional benefit was noted from the addition of plasma to the additive solution. The additive solutions compared favorably with CPDA-1.     

Evaluation of the utility and accuracy of body fluids containing red blood cells to determine canine and feline blood types

Objective

To examine the accuracy of using body fluids macroscopically suspected to contain erythrocytes to determine the blood type in dogs and cats by use of an immunochromatographic cartridge (ICC), compared to systemic blood as the reference standard.

Design

Prospective study.

Setting

University teaching hospital.

Animals

Thirty client-owned dogs and 8 cats.

Interventions

Dogs and cats with a sanguineous or serosanguineous body fluid (SBF) that also required a blood sample were eligible for inclusion. PCV and blood type were determined in all blood and fluid samples. For body fluids with a low PCV and discordant blood type results compared to systemic blood, sample concentration and repeat blood typing from the fluid was performed when enough sample was available.

Measurement and Main Results

Body fluid samples consisted of 16 pleural (11 dogs; 5 cats), 12 peritoneal (10 dogs; 2 cats), and 4 canine pericardial effusions, 3 urine samples, and 1 each of feces and epistaxis from dogs and a seroma sample from a cat. Median (range) manual PCV of blood and fluid samples was 34% (14%–66%) and 6% (0.5%–70%) for dogs and 28% (14%–48%) and 14% (0.5%–19%) for cats, respectively. Dogs were correctly classified as being DEA 1 negative, DEA 1 positive, and DEA 1 weak positive when using body fluid for blood typing 13 of 14, 4 of 9, and 5 of 7, respectively. All reference blood type to fluid blood type (FBT) discordant results had a body fluid PCV equal to or below 2%. Subsequently concentrated body fluid samples had a PCV above 8% and repeat FBT matched reference blood type (RBT). All cats were classified as type A by all RBTs and FBTs.

Conclusions

Body fluids containing erythrocytes may be utilized to blood type dogs if sufficiently concentrated and type A cats.     

Spontaneously active suppressive cells in canine peripheral blood

The phenomenon of the unusually high spontaneous suppressive activity of cells in peripheral blood of dogs was analysed. The m/c (mitomycin C)-treated population of peripheral blood leucocytes (PBL) contained cells able to reduce the responsiveness of autologous cells by 48 +/- 15% (P less than 0.01) and their activity was not indomethacin dependent. Thoracic duct lymphocytes (TDL) did not reduce the response of PBL to PHA, neither did cell crowding. The supernatants from 24-h cultures of m/c-treated PBL did not affect the response to PHA, and parallelly precultured cells inhibited the proliferation of PBL to a lesser degree (24 +/- 9%) than the fresh cells (50 +/- 16%, P less than 0.05). Addition of m/c-treated polymorphonuclear cells at PMN to PBL ratios of 1:4 and 1:1 progressively inhibited PBL reactivity to PHA, from 29.5 +/- 3.5% to 68.5 +/- 9%, respectively, and the supernatants from 24-h cultures of PMN reduced the proliferation by 48 +/- 2.8%. The neutrophil-derived inhibitory factor(s) was non-cytotoxic and reduced the formation of blasts to 61.5 +/- 3.5% of the control values. These results indicate that dog PBL from Lymphoprep gradient contain a population of non-recirculating, short-lived, spontaneously suppressive cells, mainly PMN, which modulate T cell reactivity in vitro, suggesting that neutrophils may be able to exert a regulatory effect in vivo.     

Mycoplasma gallisepticum-induced alterations in chicken red blood cells

Incubation of Mycoplasma gallisepticum with washed chicken red blood cells for 1 hr or 5 hr resulted in altered red blood cell surface morphology and perforations of the cells.     

Generation of canine dendritic cells from peripheral blood mononuclear cells

Dendritic cells (DCs) are the most potent antigen-presenting cells that are expected to be therapeutic agents for tumor immunotherapy. In this study, we generated DCs of sufficient number for DC-based immunotherapy from peripheral blood mononuclear cells (PBMC) in dogs. PBMC were cultured in the presence of phytohemagglutinin (PHA). On day 6, large adherent cells with dendrite-like projections were seen, and the number of these large cells with projections increased on day 8. These cells were positive for esterase staining. They expressed MHC class II, CD11b, CD8 and weakly CD4 on their surface. They tended to make contact with lymphocytes under culture conditions. We obtained about 2-5 x 10(6) of DCs from 10 ml of peripheral blood. These DCs phagocytosed HEK-293 cells by overnight co-culturing. These cells generated from PBMC are possible canine DCs and are applicable to clinical trials of DC-based whole tumor cell immunotherapy in dogs.     

Haemoglobin oxygen affinity and regulating factors of the blood oxygen transport in canine and feline blood

Complete dynamic oxygen equilibrium curves (OEC) on dogs and cats whole blood were measured at 33, 37 and 41 degrees C. OEC were also run at three partial carbon dioxide pressures (20, 40 and 80 mmHg) as well as at five pH levels (7.2, 7.3, 7.4, 7.5 and 7.6). 2,3- diphosphoglycerate (DPG) concentrations were determined. Results were compared to those previously published in humans, using the same experimental method [Comp. Biochem. Physiol. 106 (1993) 687]. In standard conditions (pH 7.4, pCO2 40 mmHg and temperature 37 degrees C), the partial oxygen pressure at half-saturation of haemoglobin (p50) was 30.0+/-1.3 mmHg for dogs and 34.1+/-1.8 mmHg for cats. Cat's OEC was thus rightshifted compared to dog's OEC, itself rightshifted compared to human OEC. 2,3-DPG concentrations were higher in dogs than in men until they were very low in cats. Contrary to that observed in human medicine, no significant correlation was identified between standard p50 and canine 2,3-DPG values. Influence of pH, pCO2 and temperature on the OEC was saturation dependent. In dogs, Delta log p50/Delta pH was equal to -0.370, Delta log p50/Delta log pCO2 was 0.093 and Delta log p50/Delta T was 0.020. In cats, Delta log p50/Delta pH was equal to -0.405, Delta log p50/Delta log pCO2 was 0.080 and Delta log p50/Delta T was 0.016. Practically, temperature and pH variations exert a lesser influence in domestic carnivores than in humans, effect of pCO2 being similar in both.     

Thiopurine methyltransferase activity in red blood cells of dogs

Thiopurine methyltransferase (TPMT) is an important enzyme in the metabolism of thiopurine medications such as azathioprine. In humans, activity varies widely among individuals, primarily because of genetic polymorphisms. Low TPMT activity increases the risk of myelosuppression from azathioprine and 6-mercaptopurine, whereas high TPMT activity is associated with poor drug efficacy. The purpose of this study was to determine whether dogs also show a wide range of TPMT activity. Heparinized blood samples were obtained from 177 dogs associated with a veterinary teaching hospital. Red blood cell (RBC) TPMT activity was measured by means of a modification of a radiochemical method as established for use in people. TPMT activity varied across a 9-fold range (7.9-71.8 U of RBC per milliliter; median, 21.7). Variation in TPMT activity was not associated with age, sex, or neutering status. Giant Schnauzers had much lower TPMT activity (7.9-20 U of RBC per milliliter; median, 13.1; P < .001) than did other breeds, and Alaskan Malamutes had much higher TPMT activity (22.7-71.8 U of RBC per milliliter; median, 36.0; P < .001) than did other breeds. Such variations in TPMT activity in the canine population and within groups of related dogs could affect thiopurine drug toxicity and efficacy in canine patients.