Cat Erythrocytes Research Articles

Comparison of immunoglobulin Y antibody production in new and spent laying hens.

Immunoglobulin (Ig)Y, a specific type of Ig found in chicken eggs, has potential use in the diagnosis of human and animal diseases. This study assessed the feasibility of using spent laying hens to produce IgY. In addition, the effects of antigen injection on egg and antibody production in new and spent laying hens were compared. Hens were intramuscularly injected with three booster shots of antigens. IgY was extracted from egg yolks using polyethylene glycol 6000 precipitation followed by dialysis. Spent laying hens (83 weeks) consistently showed lower egg production than new laying hens (27 weeks) throughout the study. Post-immunization, a further decline in egg production was observed in spent laying hens, and egg production stopped after the second antigen injection. Eggs from spent laying hens were less dense than eggs from new hens. Despite lower IgY levels in eggs from spent laying hens, the heavy-to-light chain ratio remained consistent in both groups. Notably, IgY from spent and new laying hens demonstrated effective hemagglutination against cat erythrocytes in the A blood group. This study demonstrated the potential of using spent laying hens to produce IgY, with significant implications for future research, immunotherapy, and diagnostic applications, despite the observed reduction in egg production compared with new laying hens.

UNILATERAL RHINITIS AND HEMOBARTONELLA FELIS INFECTION IN DOMESTIC CATS WITH A HISTORY OF CHRONIC KIDNEY DISEASE

Rhinitis is an inflammation of the mucous membranes of the nasal cavity, which can arise from a number of intranasal or systemic disorders. Hemobartonella felis is a gram-negative intracellular bacterium that attacks cat's erythrocytes. This treatment aims to discuss diagnostic and treatment techniques for rhinitis and Hemobartonellosis infection in cat with kidney failure. The animal is a local cat with a history of kidney failure, female, 6 years old and weighing 2.7 kg. The owner came with complaints of a serous discharge in the right nasal cavity and occasional sneezing. The cat has decreased appetite since 6 months and looks weak. Clinical examination showed swelling of the right mandibular lymph nodes and inspection of the oral cavity found gingivitis, tartar, and halitosis. Routine hematological examination results showed that the cat had macrocytic hypochromic anemia accompanied by thrombocytopenia. Examination of the blood smear preparations found coccoid formations with short chains or rod formations in the cat's erythrocytes which indicated a positive result for Hemobartonella felis. Case animal was diagnosed with unilateral rhinitis and Hemobartonella felis infection. The therapy given consisted of Doxycycline antibiotics at a dose of 10 mg/kg once a day for 14 days, anti-inflammatory Dexamethasone at a dose of 0.5 mg once a day for 5 days and Sangobion as a supportive therapy 1 capsule once a day for 10 days. The therapy given helps to improve the condition of the case animal. General check up of health conditions is required during the maintenance period.

Correlation between sphingomyelin and the membrane stability of mammalian erythrocytes.

Lipid compositions of mammalian erythrocyte membranes are different among species. Therefore, the information on hemolysis from mammalian erythrocytes is useful to understand membrane properties of human erythrocytes. In this work, pressure-induced hemolysis and hypotonic one were examined using erythrocytes of human, sheep, cow, cat, dog, pig, horse, rat, and mouse. Pressure-induced hemolysis was suppressed by membrane sphingomyelin, whereas hypotonic hemolysis decreased upon increment of cell diameter. Mass spectra of erythrocyte membrane lipids demonstrated that sphingomyelin with an acyl chain 24:1 was associated with the suppression of pressure-induced hemolysis. In cow erythrocytes, pressure-induced hemolysis was greatly suppressed and the detachment of cytoskeletal proteins from the membrane under hypotonic conditions was also inhibited. Taken together, these results suggest that sphingomyelin with 24:1 fatty acid plays an important role in the stability of the erythrocyte membrane, perhaps via cholesterol.

Age-and sex-related changes in selected hematological parameters, lipid peroxidation and erythrocytes osmotic fragility of Turkish Angora cats

This study was conducted to investigate the changes in selected hematological parameters, lipid peroxidation and osmotic fragility of erythrocytes in Angora cats depending on the age and gender. For this purpose, the blood samples were collected from 9 young and 14 adult cats which also classified as male (n=12) and female (n=11). Following hematological analysis, samples were washed with PBS by centrifugation and 10% hematocrit suspension was prepared from the erythrocytes pellet for osmotic fragility test. The concentration of malondialdehyde (MDA) was also measured from lysed erythrocyte to determine lipid peroxidation level. Red blood cells (RBCs), hemoglobin, and hematocrit were high in adults while mean corpuscular volume, mean corpuscular hemoglobin, and mean corpuscular hemoglobin concentration were high in young cats. Erythrocyte MDA level was also higher in adult cats than in young cats. There was no significance in these parameters between male and female cats. Findings of fragility tests were showed that erythrocytes of young and male cats were more susceptible to hypotonic NaCl solutions than those of adult and female cats, respectively. It was concluded that erythrocytes related parameters in Angora cats changed depending on the age rather than gender except stability of RBCs.

Molecular characterization of cytidine monophospho-N-acetylneuraminic acid hydroxylase (CMAH) gene and frequency of blood types in stray cats of \u0130zmir, Turkey

BackgroundCytidine monophospho-n-acetylneuraminic acid hydroxylase (CMAH) gene associated with blood groups in cats encodes CMAH enzyme that converts Neu5Ac to Neu5Gc. Although variations in CMAH gene of pedigree cats have been revealed, the presence/lack of them in non-pedigree stray cats is unknown. Therefore, the present study aimed to investigate the variations in CMAH gene and the quantity of Neu5Ac and Neu5Gc on erythrocytes of non-pedigree stray cats (n:12) living in İzmir, Turkey. Also, the frequency of blood types was determined in 76 stray cats including 12 cats that were used for CMAH and Neu5A/Neu5Gc analysis.ResultsIn total, 14 SNPs were detected in 5’UTR as well as in exon 2, 4, 9, 10, 11 and 12 of CMAH gene. Among these SNPs, -495 C > T in 5’UTR was detected for the first time as heterozygous in type A and AB cats, and homozygous and heterozygous in type B cats. The remaining 13 that have been detected in previous studies were also found as homozygous or heterozygous. Both Neu5Gc and Neu5Ac were detected in type A and AB cats. In type B cats, only Neu5Ac was detected. Among two type AB cats, the level of Neu5Ac was found higher in cat carrying heterozygous form (T/C) of 1392T > C. The prevalence of type B cats (67.1 %) was higher than others.ConclusionsThe presence of a new SNP as well as previous SNPs indicates that more variations can be found in stray cats with a more comprehensive study in the future. Also, the high prevalence of type B cats demonstrates the possible risk of neonatal isoerythrolysis among stray cats living in İzmir, Turkey.

Lifetime diagnosis of carnivore plague

Main problem: Until now the problem of intravital direct diagnosis of canine plague (Kara's disease), aimed at detecting the viral antigen in the secretions and excretions of sick animals, remains urgent. In the case of the disease of carnivorous dogs, the issue of reliable intravital diagnosis is more urgent, since the plague of carnivores in dogs is treated. Lifetime diagnosis of this disease by methods applicable in veterinary clinics is preferable, since in the case of timely and correct diagnosis, therapeutic measures will be more effective. Purpose: To improve the system of antiepizootic measures against canine plague among dogs in terms of prevention, diagnosis and treatment of this disease. Methods: Analysis of data from private veterinary clinics reporting on the incidence of small domestic animals was used. Various serological methods were used. Differential diagnosis from infectious hepatitis in dogs was carried out by means of CBR, DPR, from parvovirus enteritis - by HIR with cat erythrocytes. To check the specificity of reactions and determine the concentration of the test material, excluding false positive results, samples of pathological material obtained from dogs with various infectious diseases, as well as those obtained from healthy intact animals, were examined. Results and their significance: The use of a complex of various diagnostic methods ensures the diagnosis of plague of carnivores in any form of the disease and at any stage, even in the case of mixed infections, as well as differentiate it from parvovirus enteritis, infectious hepatitis and other carnivorous diseases similar to plague. Valuable in the RAM for the detection of the virus-specific antigen of the plague of carnivorous virus is that it can be used to diagnose the disease in vivo by examining fecal samples and swabs from the oral and nasal cavities.

Oxidative status of erythrocytes, hyperglycemia, and hyperlipidemia in diabetic cats.

BackgroundErythrocytes of diabetic cats have decreased superoxide dismutase activity, possibly indicative of oxidative stress.HypothesisErythrocytes of diabetic cats undergo oxidative stress, which is caused by hyperglycemia and hyperlipidemia, and improves with treatment.AnimalsTwenty‐seven client‐owned cats with diabetes mellitus, 11 matched healthy cats, and 21 purpose‐bred healthy cats.MethodsProspective study. Advanced oxidized protein products, carbonyls (protein oxidation by‐products), and thiols (antioxidants) were quantified in erythrocyte membrane, thiobarbituric acid reactive substances (TBAR, lipid peroxidation by‐products), and thiols in erythrocyte cytoplasm of all cats. Comparison were performed between diabetic and matched healthy cats, between diabetic cats achieving remission or not, and among purpose‐bred cats after 10 days of hyperglycemia (n = 5) or hyperlipidemia (n = 6) versus controls treated with saline (n = 5) or untreated (n = 5).ResultsCompared with controls, erythrocytes of diabetic cats initially had higher median membrane carbonyls (4.6 nmol/mg total protein [range: 0.1‐37.7] versus 0.7 [0.1‐4.7], P < .001) and lower cytoplasmic TBAR (1.9 nmol/mg [0.5‐2.4] versus 2.4 [1.4‐3.5] P < .001), and thiols (419 nmol/mg [165‐621] versus 633 [353‐824], P < 0.001). After 12‐16 weeks of treatment in diabetic cats, carbonyls decreased by 13% (P < .001), but remained higher (P < .001) and TBAR and thiols lower (P = .02, P < .001) than those in controls. No differences were observed between diabetic cats achieving remission or not, and among purpose‐bred cats.Conclusions and Clinical ImportanceDiabetes mellitus is associated with increased protein oxidation and reduced antioxidant defenses, which persist during treatment and remission, although mild improvement in protein oxidation occurs. Short‐term hyperglycemia or hyperlipidemia does not cause oxidative stress. The reason for decreased TBAR remains unknown.

Glutathione peroxidase of blood of dogs and cats with mammary tumors

For timely diagnostics and successful treatment of mammary tumors in human and animals a necessary search of compounds that can be the biomarkers of this disease is needed. The aim of our work was to measure the activity of glutathione peroxidase (GPx) in blood plasma and erythrocytes of dogs and cats with mammary tumors and healthy animals for establishment of intercommunication between enzyme's activity and tumors. For researches took away blood at three groups of animals: 1) four healthy females of dogs (Canis familiaris) – the German Shepherd dogs by age 3, 6, 7 and 7; 2) four females of dogs with mammary tumors – the Russian Spaniel dog by age 8, Boxer dog by age 9 and the German Shepherd crossbred dogs by age 11 and 12; 3) four females of cats (Felis catus) with mammary tumors – crossbred cats by age 6, 8 and 10 and the Persian crossbred cat by age 13. Activity of GPx was determined by decrease of reduced glutathione in a presence of hydrogen peroxide for time unit with a count on the gramme of protein in blood plasma, or haemoglobin in erythrocytes. In the sick dogs’ erythrocytes the activity of GPx presents 30.45 ± 3.08 mmol GSH/min×g haemoglobin and it is more than for the healthy animals of 27.84 ± 5.24 mmol GSH/min×g haemoglobin, these differences aren't statistically reliable however. This index is the highest for the sick German Shepherd crossbred dog aged 11 and presents 38.5 mmol GSH/min×g haemoglobin. In sick dogs’ activity of GPx in blood plasma is 7.45 ± 1.60 mmol GSH/min×g protein and it is statistically reliable less than the healthy animals of 12.77 ± 1.18 mmol GSH/min×g protein. This index is the lowest for the the 12 years old sick German Shepherd crossbred dog and it is 3.41 mmol GSH/min×g protein. In sick cats activity of GPx in erythrocytes is 41.57 ± 4.10 mmol GSH/min×g haemoglobin, and the greatest it is in the sick crossbred cat age 10 – 52.52 mmol GSH/min×g haemoglobin. The activity of the enzyme in blood plasma of sick cats is 11.58 ± 1.99 mmol GSH/min×g protein and this index is similar to the healthy dogs. Activity of GPx of the erythrocytes of dogs and blood plasma of cats with mammary tumors did not differ from healthy dogs. The activity of GPx of sick dogs only in blood plasma is less than in healthy ones. It can be the consequence of this “exhaustion” of the enzyme and its involving in the process of neutralizing of active forms of reactive oxygen species in those tissues of organism where oxidizing stress develops. Next to the study of expression on the future it is necessary to pay attention to the study of polymorphism of GPx.

Comparative serological investigation between cat and tiger blood for transfusion

Evidence suggests that non-domesticated felids inherited the same AB-erythrocyte antigens as domestic cats. To study the possible compatibility of tiger blood with that of other endangered felidae, blood samples from captive tigers and domestic cats were subjected to an in vitro study. The objectives of this study were to (1) identify whether the captive tigers had blood type AB and (2) determine the compatibility between the blood of captive tigers and that of domestic cats with a similar blood type. The anti-coagulated blood with ethylenediaminetetraacetic acid of 30 tigers was examined to determine blood type, and a crossmatching test was performed between tiger and cat blood. All 30 tigers had blood type A. Tube agglutination tests using tiger plasma with cat erythrocytes resulted in 100% agglutination (n=30) with type B cat erythrocytes and 76.7% agglutination (n=23) with type A cat erythrocytes. The 80% of major and 60% of minor compatibilities between blood from 10 tigers and 10 domestic cats with blood type A were found to pass compatibility tests. Interestingly, 3/10 of the tigers’ red blood cell samples were fully compatible with all cat plasmas, and 1/10 of the tiger plasma samples were fully compatible with the type A red cells of domestic cats. Although the result of present findings revealed type-A blood group in the surveyed tigers, the reaction of tiger plasma with Type-A red cell from cats suggested a possibility of other blood type in tigers.

The Effect of an Increased Training Volume on Oxidative Stress

This study examined the influence of training volume on resting and exercise-induced plasma markers of oxidative stress (MDA concentration) and antioxidant status (GPX, CAT & SOD erythrocyte activities). Moderately trained participants (TG) (n=6; 4 males and 2 females; 25±1.8 years) and sedentary control subjects (CG) participated in the 8-week investigation. The TG increased their training volume from ~4.9 to ~18 h.wk-1 by the end of the investigation. Before the increase in training volume and at 2-week intervals the TG completed a 30 km cycling time trial (TT30) where resting-and post-exercise blood was -sampled and analysed for oxidative stress and antioxidant status. The CG had their resting blood sampled and analysed fortnightly. The data showed that TT30 performance improved in the first 4 weeks but remained unchanged in the last 4. Resting plasma MDA and CAT increased in response to training, with no change in the resting activities of erythrocyte GPX and SOD. Post-TT30 MDA and CAT increased over the training period and training hours positively related to both resting-and post-TT30 MDA. The increase in resting MDA and the up-regulation in CAT in response to an increased training volume may have a role in the identification of a training and performance plateau.

Biochemical and functional characterization of a C-type lectin (BpLec) from Bothrops pauloensis snake venom

In the present work, we report the isolation and partial biochemical characterization of BpLec, a C-type lectin purified from Bothrops pauloensis venom by one chromatographic step on an affinity agarose column immobilized with d-galactose. This protein was homogeneous by SDS-PAGE under reducing and nonreducing conditions, and was shown to be a 33.6kDa homodimer by MALDI TOF analysis. BpLec presented an isoeletric point of 5.36. Its partial sequence of 132 amino acids for each subunit, determined by Edman degradation, revealed high identity (between 86% and 95%) when aligned with sequences of other related proteins. BpLec was capable of agglutinating native dog and cat erythrocytes and this activity was inhibited by β-galactosides and EDTA. Its hemagglutinating activity was abolished at high temperatures and stable in any pH range. BpLec was effective in inhibiting Gram-positive but not Gram-negative bacteria. In addition, BpLec agglutinated promastigote forms of Leishmania (Leishmania) amazonensis.

The role of para‐aminophenol in acetaminophen‐induced methemoglobinemia in dogs and cats

Acetaminophen (APAP) overdose in most species is associated with hepatotoxicity because of the metabolite N-acetyl-p-benzoquinoneimine (NAPQI). In dogs and cats, APAP overdose primarily causes methemoglobinemia and hemolysis. Although NAPQI has been proposed as the responsible intermediate in dogs and cats, it lacks chemical or pharmacokinetic characteristics that favor methemoglobin formation. We hypothesized that para-aminophenol (PAP) rather than NAPQI induces methemoglobinemia and that deficient arylamine N-acetyltransferase (NAT) activity in dogs and cats contributes to this species-dependent methemoglobinemia. Erythrocytes from dogs, cats, mice, and rats were exposed in vitro to APAP, NAPQI, and PAP. Only PAP induced methemoglobin and it induced more methemoglobin formation in dog and cat than rat and mouse erythrocytes. PAP also induced more methemoglobin in erythrocytes from Nat1/Nat2 knockout mice than wildtype (WT) mouse erythrocytes (P < 0.05), but less than in dog and cat erythrocytes (P < 0.01). APAP and PAP toxicity were compared in vivo in WT and Nat1/Nat2 knockout mice. APAP caused no hematotoxicity while PAP induced more methemoglobin in NAT1/NAT2 knockout mice than in WT mice (P < 0.05). These results support the hypothesis that PAP is the metabolite responsible for APAP-induced methemoglobinemia and that deficient NAT activity in dogs and cats contributes to this species-dependent toxicity.

Cytotoxicity and hemolytic activity of jellyfish Nemopilema nomurai (Scyphozoa: Rhizostomeae) venom

The recent bloom of a giant jellyfish Nemopilema nomurai has caused a danger to sea bathers and fishery damages in the waters of China, Korea, and Japan. The present study investigated the cytotoxic and hemolytic activities of crude venom extract of N. nomurai using a number of in vitro assays. The jellyfish venom showed a much higher cytotoxic activity in H9C2 heart myoblast than in C2C12 skeletal myoblast (LC 50 = 2 µg/mL vs. 12 µg/mL, respectively), suggesting its possible in vivo selective toxicity on cardiac tissue. This result is consistent with our previous finding that cardiovascular function is a target of the venom. In order to determine the stability of N. nomurai venom, its cytotoxicity was examined under the various temperature and pH conditions. The activity was relatively well retained at low environmental temperature (≤ 20 °C) and dramatically lost at high temperature (≥ 60 °C). In pH stability test, the venom has abruptly lost its activity at low pH environment (pH ≤ 4). Interestingly enough, however, its activity was not significantly affected even at the highest pH environment tested (pH ≤ 12) in the present study. Additionally, hemolytic activity of the venom was examined using the erythrocytes of cat, dog, human, rabbit and rat. Venom concentration-dependent hemolysis could be observed from 10 µg/mL of protein equivalents or higher with variable potencies in different species, among which dog erythrocyte was the most susceptible to the venom (EC 50 = 151 µg/mL). SDS-PAGE analysis of N. nomurai venom showed the molecules of 20–40 kDa and 10–15 kDa appeared to be the major protein components of the venom.

Studies on the factors affecting the growth and hemolytic activity of Anabaena variabilis

The hemolytic activity of the cell-free culture supernatant of Anabaena variabilis OL S1 was investigated using the hemolysis of rabbit erythrocytes as an assay. The culture medium of A. variabilis started to exhibit hemolytic activity at the late exponential growth phase, and maximized at the stationary phase. The hemolytic toxin is heat-stable and can be extracted in dichloromethane. The hemolytic activities under different temperature, light intensity and pH showed a high correlation with the cell densities (r=0.965, 0.951, 0.865, respectively), and the optimum condition is 28~30°C, pH 7.5~8.0, light intensity 120 μmol photons m−2s−1. The addition of 10~20 μg mL−1 chloramphenicol, an inhibitor of protein synthesis, exhibited no marked suppression on the hemolytic activity. The supplement of 1~20 μg mL−1 glycerol increased the hemolytic activity significantly, suggesting that synthesis of hemolysin was dependent on carbohydrate and lipid metabolism. The spectrum of erythrocyte sensitivity to the hemolysin indicated that rabbit erythrocytes were more sensitive to the hemolysin than were rat and human erythrocytes. Goldfish and cat erythrocytes were, however, insensitive to the hemolytic toxin of A. variabilis.

Bartonella henselae Infects Human Erythrocytes

Bartonella henselae, a facultative intracellular bacterium, has been known as the agent of cat scratch disease, bacillary angiomatosis, peliosis hepatis, endocarditis, and bacteremic syndrome in humans. Bartonella species can cause intraerythrocytic infections and have been isolated from the bloodstream of patients by several methods. It was demonstrated that B. bacilliformis and B. quintana infect human endothelial cells and human erythrocytes and B. henselae infects erythrocytes of cats. The aim of this study was to investigate through transmission electron microscopy whether B. henselae infects mature human erythrocytes. One red blood cell (RBC) unit received an experimentally standard strain of B. henselae. Blood aliquots were collected from the infected unit immediately after inoculation, at 30 min and 1, 5, 10, and 72 h for ultrastructural evaluation. B. henselae was seen adhering to human erythrocytes 10 h after inoculation and inside the erythrocyte after 72 h. This study demonstrates that B. henselae adheres to and invades mature human erythrocytes. The results favor the possibility that erythrocytes can serve as a primary target in Bartonella spp. infections. From this observation, further studies are warranted to prevent Bartonella spp. transfusional transmission.

Phenotypic differences within the AB blood type of the feline AB blood group system

Flow cytometry immunolabeling, tube agglutination tests, and thin-layer chromatography immunostaining with two different anti-A monoclonal antibodies (anti-A mAb1 and anti-A mAb2) and one anti-B mAb were used to demonstrate differences in expression of the A and B antigens among erythrocytes from type A and four different type AB cats. Although the flow cytometric patterns of reactivity and agglutination scores for erythrocytes from types A and B cats detected with the anti-A and anti-B mAbs were consistent, reactivity among erythrocytes of different type AB cats was variable. By flow cytometric analysis, 99.9% of type A erythrocytes, no type B erythrocytes, 2.5–4.0% of erythrocytes from type AB cats 1, 3, and 4, and 60.7% of erythrocytes from type AB cat 2 had detectable A antigen when anti-A mAb1 was used. In contrast, 86.4% of type A erythrocytes, no type B erythrocytes, 20.2–38.0% of erythrocytes from type AB cats 1, 3, and 4, and 68.5% of erythrocytes from type AB cat 2 had detectable A antigen when anti-A mAb2 was used. In addition, 86.9% of type B erythrocytes, no type A erythrocytes, 83.1–96.8% of erythrocytes from type AB cats 1, 3, and 4, and 73.0% of erythrocytes from type AB cat 2 had detectable B antigen when the anti-B mAb was used. Agglutination scores of type AB cats were comparable to the percent binding on flow cytometry. Thin-layer chromatography immunostains confirmed differences in the amount of A antigen between erythrocyte glycolipids of type A and AB cats and those of type AB cats 1 and 2. These results suggest that at least two different phenotypes exist within the feline AB blood type, which differ in the amount of A antigen expressed on the erythrocyte surface.

Recommendations for treatment of human infections caused by Bartonella species.

Members of the genus Bartonella are facultative intracellular bacteria belonging to the alpha 2 subgroup of the class Proteobacteria and are phylogenetically closely related to Brucella species (15, 73). Until 1993, only three diseases were known to be caused by Bartonella species: Carrion's disease (Bartonella bacilliformis), trench fever (Bartonella quintana), and cat scratch disease (CSD; Bartonella henselae). The genus now comprises B. bacilliformis, species of the former genera Rochalimea and Grahamella (14, 18), and additional, recently described species (Table ​(Table1).1). In mammals, each Bartonella species is highly adapted to its reservoir host; the bacteria can persist in the bloodstream of the host as the result of intraerythrocytic parasitism (49). Intraerythrocytic localization of B. henselae has been demonstrated in cat erythrocytes (88), and B. bacilliformis bacilli have been observed within erythrocytes during the acute phase of Carrion's disease (Oroya fever) (88). Bartonellae also have a tropism for endothelial cells, and intracellular B. henselae can be identified in endothelial cells infected in vitro (28), although intraendothelial cell bacilli have not been identified in vivo. TABLE 1. Epidemiological and clinical data for species of the genus Bartonella Bartonella species cause long-recognized diseases, such as Carrion's disease, trench fever, and CSD, and more recently recognized diseases, such as bacillary angiomatosis (BA), peliosis hepatis (PH), chronic bacteremia, endocarditis, chronic lymphadenopathy, and neurological disorders (Table ​(Table2)2) (73). A remarkable feature of the genus Bartonella is the ability of a single species to cause either acute or chronic infection and either vascular proliferative or suppurative manifestations. TABLE 2. Human diseases caused by Bartonella spp. The pathological response to infection with Bartonella spp. varies substantially with the status of the host immune system. Indeed, infection with the same Bartonella species (e.g., B. henselae) can result in a focal suppurative reaction (CSD in immunocompetent patients), a multifocal angioproliferative response (BA in immunocompromised patients), endovascular multiplication of the bacteria (endocarditis), or an exaggerated inflammatory response without evidence of bacteria in patient tissues (meningoencephalitis) (86). Some of the diseases due to Bartonella species can resolve spontaneously without treatment, but in other cases, the disease is fatal without antibiotic treatment and/or surgery. The clinical situations are so different that a single treatment for all Bartonella-related diseases has not been identified, and the approach to treatment must be adapted to each species and clinical situation (49). Moreover, the database of clinical studies with a standard case definition, culture confirmation, rigidly defined disease outcomes, and patients with similar host defenses is very limited. Thus, case reports with a very limited number of subjects often serve to dictate therapy. The objective of this minireview is to summarize the antibiotic treatment recommendations for the different infections caused by Bartonella species. We have compiled the in vitro antibiotic susceptibility data and our knowledge of the in vivo efficacies of antibiotics for each clinical manifestation, and finally, we have summarized and ranked our treatment recommendations according to the Infectious Diseases Society of America (IDSA) practice guidelines (see Table ​Table5)5) (51). TABLE 5. System for ranking recommendations in clinical guidelines recommended by IDSAa

Tritrichomonas foetus: a scanning electron microscopy study of erythrocyte adhesion associated with hemolytic activity

The in vitro hemolytic activity of Tritrichomonas foetus was investigated. The parasite was tested against human erythrocytes of groups A, B, AB, and O, and against erythrocytes of nine adult animals of different species (the rabbit, rat, chicken, cat, dog, swine, horse, bovine, and sheep). The results showed that T. foetus strains (ATCC KV1, K, PAL, 5022, RJ, 90) did not present any hemolytic activity against any human erythrocyte group nor against rabbit, rat, chicken, cat, dog and swine erythrocytes. T. foetus strains, however, lysed horse, bovine, and sheep erythrocytes. No hemolysin released by the parasites could be identified. Hemolysis did not occur with trichomonad culture supernatants, with sonicated extracts of T. foetus, nor with killed organisms. Scanning electron microscopy (SEM) showed that human erythrocytes did not adhere to the trophozoites, in contrast horse erythrocytes adhered to the surface of the parasites and were phagocytosed for up to 90 min. The parasites are able to exert their cytopathic effects through: (a) physical contact established between the two cell surfaces, (b) toxins released from parasites into the interaction media, or (c) the association of both mechanisms. Further studies are necessary to clarify the importance of the hemolytic activity in the biology of T. foetus.

Demonstration of Thiopurine Methyltransferase Activity in the Erythrocytes of Cats

Azathioprine is a purine analogue used as an immunosuppressive and immunomodulator agent in various mammals, including cats. Several adverse reactions have been reported and have limited the use of the drug in the cat. Adverse reactions to azathioprine in humans have been correlated with reduced activity of thiopurine methyltransferase (TPMT) in erythrocytes. The purpose of this preliminary study was to determine if cats have TPMT activity in their erythrocytes and to compare the values obtained with the normal range for humans and the normal range for dogs in a preliminary report. Activity of the enzyme was measured in blood samples drawn from 41 cats. Blood also was taken from 5 dogs. The mean erythrocyte TPMT activity in the cats was 2.4 ± 0.4 nmol (range, 1.2–3.9 nmol) per hour per milliliter of red blood cells (U/mL RBC) or 2–8 nmol per hour per gram of hemoglobin (U/g Hb). This range was far lower than the normal human range (8–15 U/mL RBC; 16–33 U/g Hb) and was of monopolar distribution. This observation apparently precludes any diagnostic purpose in assaying erythrocyte TPMT in this species. Erythrocyte TPMT activity in the 5 dogs ranged from 5.5 to 13.1 U/mL RBC (11–27 U/g Hb), which was comparable with normal and carrier ranges for humans, but proof of TPMT genetic polymorphism in either species will require genotyping studies.

Hemin-dependent growth and hemin binding of Bartonella henselae

Bartonella henselae causes cat-scratch disease and bacillary angiomatosis peliosis. The bacteria reside in erythrocytes of asymptomatic cats, which represent the natural reservoir for this pathogen. B. henselae is usually grown on blood-enriched media. Growth experiments on Brucella medium without blood demonstrated that heme compounds are essential for the growth of B. henselae and can completely substitute the addition of blood components. The heme precursor protoporphyrin IX alone, or in combination with FeCl 2 or FeCl 3, as well as transferrin or lactoferrin did not support growth, indicating that B. henselae cannot synthesize heme itself. Hemin supported growth even when free iron was chelated, indicating that hemin is also used as an iron source. Binding assays showed that hemin starvation increased the binding capacity of B. henselae for hemin, providing evidence that the bacteria carry a specific hemin uptake system, which might be regulated by hemin.