Reduced IL-2 and IL-4 mRNA Expression in CD4+ T Cells from Bovine Leukemia Virus-Infected Cows with Persistent Lymphocytosis

ABSTRACT Interleukin-12 (IL-12), a key cytokine in immune regulation, has an important role in activating the cell-mediated immune response in infectious diseases. Recently, a dichotomy between IL-12 and IL-10 regarding progression of a variety diseases has emerged. IL-12 activates type 1 cytokine production and has an antagonistic effect on type 2 cytokines. Here, by using quantitative competitive PCR, we show that peripheral blood mononuclear cells from bovine leukemia virus-infected animals in the alymphocytotic stage of disease express an increased amount of IL-12 p40 mRNA. In contrast, IL-12 p40 mRNA expression by cells from animals with late-stage disease, termed persistent lymphocytosis, was significantly decreased compared to that by normal and alymphocytotic animals. Interestingly, IL-12 p40 mRNA was also detected in tumor-bearing animals. IL-12 p40 expression occurred only in monocytes/macrophages, not B or T lymphocytes. The present study combined with previous findings suggest that IL-12 in bovine leukemia virus-infected animals may regulate production of other cytokines such as gamma interferon and IL-10 and the progression of bovine leukosis in animals that develop more advanced disease such as a persistent lymphocytosis of B cells or B-cell lymphosarcoma.

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Isolation of Bovine Leukemia Virus from Cows with Persistent Lymphocytosis in Iraq

Veterinary and Animal Science ◽

10.1016/j.vas.2021.100201 ◽

2021 ◽

pp. 100201

Author(s):

Yahia Ismail Khudhair ◽

Ahmed Majeed Al-Shammari ◽

Saleem Amin Hasso ◽

Nahi Yaseen

Keyword(s):

Bovine Leukemia Virus ◽

Leukemia Virus ◽

Persistent Lymphocytosis

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Influence of the Bovine Leukemia Virus on the Immunological Activity by the Neutrophilic Function

Acta Scientiae Veterinariae ◽

10.22456/1679-9216.102520 ◽

2020 ◽

Vol 48 ◽

Author(s):

Vinícius Bigolin Narciso ◽

Silvana Giacomini Collet ◽

Lilian Kolling Girardini ◽

Fernando Nogueira Souza ◽

Alcione Santa Catarina ◽

...

Keyword(s):

Oxidative Metabolism ◽

Bovine Leukemia Virus ◽

Leukemia Virus ◽

Latency Period ◽

Persistent Lymphocytosis ◽

Phagocytic Capacity ◽

Significant Difference ◽

Zymosan Particle ◽

The Impact ◽

Hematological Alterations

Background: Bovine leukemia virus (VLB) is an oncogenic deltaretrovirus associated with the development of persistent lymphocytosis (LP) and lymphosarcomas in cattle. LP is characterized by chronic elevation of the number of circulating lymphocytes, in the case of B lymphocytes. Several studies have described functional changes in various leukocyte populations in both blood and milk in VLB-infected animals. The impact of some chronic diseases of low lethality is aggravated by the emergence of comorbidities.The objective of the present study was to evaluate the oxidative metabolism and neutrophil phagocytosis of bovines of the Holtein breed naturally infected with the bovine leukemia virus (VLB).Materials, Methods & Results: In this study, 20 cows were divided into three groups: (NG) seven non-seroreagent animals for VLB and without hematological alterations; (GAL) eight seroreagent animals for VLB and without hematological alterations; and (GLP) five seroreagent animals for VLB with persistent lymphocytosis (LP). The oxidative metabolism of neutrophils was determined by the tetrazolium nitroblast reduction test stimulated or not with Zymosan particles. The percentage of neutrophils that phagocytosed Zymosan particle (s) was also evaluated. The data were initially evaluated for normality and homoscedasticity by the Shapiro-Wilk test. Then the ANOVA test followed by the Student-Newman-Keuls test was applied for the comparison between the NG, GAL and GLP animals. Comparison between the NG animals and the seroreagent animals for the VLB (GVLB) was also performed through the unpaired Student's t-test. The value of P < 0.05 was considered significant. No significant differences were observed in oxidative neutrophil metabolism in stimulated and non-stimulated samples with Zymosan particles nor in the percentage of neutrophils that phagocytosed Zymosan particle (s) among the three experimental groups. However, as no differences were observed between the seroreagent animals for VLB with and without LP, we chose to divide the animals into only two experimental, non-seroreagent and seroreagent groups for VLB. Thus, when non-seroreagent animals for the VLB were compared with the seroreagent animals for the VLB, which corresponds to the GAL and GLP animals, a significant difference was observed in relation to the oxidative metabolism by neutrophils stimulated with Zymosan particles.Discussion: Some viral diseases are often associated with increased susceptibility to new infections and several studies have evaluated the role of peripheral blood mononuclear cells in VLB infection, but few studies have investigated neutrophil function. Some authors, when evaluating phagocytic capacity and oxidative metabolism, respectively, of blood leukocytes from VLB-infected animals, observed that VLB-infected animals displaying LP had lower phagocytic capacity and lower production of Reactive Oxygen Species (ROS). Some studies have shown that oxygen consumption by neutrophils was higher in experimentally infected sheep by VLB after 15 weeks of challenge, but this species is not a natural host of the virus, since transmission does not occur between sheep and cattle and the pathogenesis of infection by VLB is more acute in sheep, a result of the lower latency period for LP development. Other authors, when evaluating the interference of VLB in milk leukocytes, concluded that VLB-infected animals show lower intensity of intracellular ROS production by flow cytometry in VLB-infected animals, especially animals expressing LP, despite the fact that percentage of milk neutrophils that produced ROS did not differ between groups. It can be concluded that VLB interferes in neutrophilic function with possible implications for the health of VLB-infected animals and may favor secondary infections.

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A hematologic key for bovine leukemia virus screening in Japanese black cattle

Journal of Veterinary Diagnostic Investigation ◽

10.1177/1040638719848449 ◽

2019 ◽

Vol 31 (4) ◽

pp. 568-571

Author(s):

Masataka Akagami ◽

Shoko Oya ◽

Yuki Kashima ◽

Satoko Seki ◽

Yoshinao Ouchi ◽

...

Keyword(s):

Dairy Cattle ◽

Bovine Leukemia Virus ◽

Operating Characteristic ◽

Leukemia Virus ◽

Characteristic Curve ◽

Persistent Lymphocytosis ◽

Cutoff Values ◽

Antibody Elisa ◽

Hematologic Method ◽

Virus Screening

The European Community’s leukosis key (EC key) is a well-known hematologic method for detecting bovine leukemia virus (BLV) infection in dairy cattle. The key identifies infected cattle with persistent lymphocytosis via a combination of lymphocyte count (LC) and age. Using the EC key to identify BLV-infected Japanese black (JB) cattle is problematic, however, given the inherently lower LCs of JB cattle compared to dairy cattle. We analyzed the LC in BLV-positive and -negative JB cattle and estimated LC cutoff values by age using receiver operating characteristic curve analysis. Among the 716 JB blood samples collected, 452 (63%) JB cattle were confirmed as BLV-positive by an antibody ELISA for ≥1-y-old cattle and by real-time PCR for <1-y-old cattle. The cutoff values for the LC in each age group were calculated as 6.3 × 109/L for <1 y, 5.9 × 109/L for 1 to <2 y, 5.5 × 109/L for 2 to <3 y, 4.5 × 109/L for 3 to <6 y, 4.3 × 109/L for 6 to ≤10 y, and 3.7 × 109/L for >10 y. The sensitivity and specificity of the estimated cutoff values were 0.49 (95% confidence interval: 0.44–0.53) and 0.81 (0.75–0.85), whereas those of the EC key were 0.20 (0.16–0.24) and 0.99 (0.97–1.00). Our LC cutoff values for screening JB cattle for BLV infection appear to be preferable to those of the EC key.

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Preliminary Study on the Abnormal DNA Methylation in T Cells from the Patients with Immune Related Pancytopenia

Blood ◽

10.1182/blood.v124.21.5156.5156 ◽

2014 ◽

Vol 124 (21) ◽

pp. 5156-5156

Author(s):

Zonghong Shao ◽

Yue Ren ◽

Rong Fu

Keyword(s):

Dna Methylation ◽

T Cells ◽

T Cell ◽

Mrna Expression ◽

Peripheral Blood ◽

Cd4 T Cells ◽

Mrna Level ◽

Cd4 T Cell ◽

Global Dna Methylation ◽

Normal Controls

Abstract Objective To explore the global DNA methylation and the expression of regulatory genes for methylation in CD4 + T cells of the patients with immune related pancytopenia (IRP) and explore the role of methylation in pathogenesis of IRP. Methods Thirty IRP patients (untreated, n=15; remission, n=15) and 15 healthy donors as controls were enrolled from December 2012 to December 2013. CD4+ T cells were sorted by immunomagnetic separation. The global DNA methylation was tested with enzyme-linked immunosorbent assay (ELISA). The mRNA levels of DNA methylation-related regulating genes, DNA methyltransferases (DNMTs) and methylated CpG binding proteins (MBDs), were measured by real-time quantitative polymerase chain reaction (RT-PCR). Results The level of global DNA methylation in peripheral blood CD4+ T cells of untreated IRP patients (3.525%±2.046%)and remission patients (4.790%±1.471%) were significantly lower than that of normal controls (10.101%±3.449%) respectively (both P<0.05). DNMT3b mRNA level of untreated IRP patients (1.332±0.785) was significantly lower than that of normal controls (2.077±1.059) in CD4+T cells (P<0.05). The mRNA expression of MBD2 was significantly higher in CD4+ T cells from untreated and remission IRP patients (2.999±1.601, 2.055±1.576) than that in controls (0.581±0.247) (both P<0.05). The MBD4 mRNA level was significantly higher in CD4+ T cells from untreated IRP patients (2.736±2.719) compared to that in normal controls (1.167±1.006) (p<0.05). DNMT3b mRNA expression and CD4+ T cell DNA methylation to be positive correlated within IRP patients (r=0.569, p<0.01). The MBD2 mRNA expression negatively correlated with CD4+ T cell DNA methylation and the ratio of Th1/Th2 (r=-0.763, p<0.001; r = -0.652, p<0.05). The global methylation of CD4+ T cells negatively related to the ratio of CD5+ B cells (r= -0.439, p<0.05). Conclusions The globe DNA hypomethylation and abnormal expression of DNA methylation-related enzymes in peripheral blood CD4+ T cells may be related with the pathogenesis of IRP. Disclosures No relevant conflicts of interest to declare.

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Cooperation of PD-1 and LAG-3 in the exhaustion of CD4+ and CD8+ T cells during bovine leukemia virus infection

Veterinary Research ◽

10.1186/s13567-018-0543-9 ◽

2018 ◽

Vol 49 (1) ◽

Cited By ~ 7

Author(s):

Tomohiro Okagawa ◽

Satoru Konnai ◽

Asami Nishimori ◽

Naoya Maekawa ◽

Shinya Goto ◽

...

Keyword(s):

T Cells ◽

Virus Infection ◽

Cd8 T Cells ◽

Bovine Leukemia Virus ◽

Leukemia Virus ◽

Bovine Leukemia Virus Infection

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Involvement of CD8+ T Cells in Delayed-type Hypersensitivity Responses against Bovine Leukemia Virus (BLV) Induced in Sheep Vaccinated with Recombinant Vaccinia Virus Expressing BLV Envelope Glycoprotein

Veterinary Pathology ◽

10.1177/030098589303000202 ◽

1993 ◽

Vol 30 (2) ◽

pp. 104-110 ◽

Cited By ~ 8

Author(s):

K. Okada ◽

S. Ikeyama ◽

K. Ohishi ◽

H. Suzuki ◽

M. Sugimoto ◽

...

Keyword(s):

T Cells ◽

Vaccinia Virus ◽

Envelope Glycoprotein ◽

Bovine Leukemia Virus ◽

Leukemia Virus ◽

Immunohistochemical Analysis ◽

Recombinant Vaccinia Virus ◽

Delayed Type Hypersensitivity ◽

Recombinant Vaccinia ◽

Lymphocytic Infiltrates

Delayed-type hypersensitivity responses against bovine leukemia virus (BLV) envelope glycoprotein (gp60) were induced in the skin of sheep vaccinated with recombinant vaccinia virus (RVV) expressing BLV glycoprotein. The lesions were characterized by marked infiltration of lymphocytes, slight migration of neutrophils, eosinophils, and macrophages in the dermis to hypodermis, and partial intercellular edema in the reticular layer. Immunohistochemical analysis with monoclonal antibodies demonstrated that the lymphocytic infiltrates consisted mainly of CD8+ T cells (53.7–55.8% at 48 hours post-challenge of BLV), CD4+ T cells (24.7–26.7%), and B cells (11.5–16.9%). The role of CD4+ and CD8+ T cells in suppressing BLV growth in RVV-vaccinated animals is discussed.

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