Lymphocytes T and B in rabbits infected with RHD virus

The aim of this study was to determine the differences in immunological response of animals infected with different antigenic variants of the virus – three haemagglutinating (Vt97, Triptis, Hartmannsdorf) and two non-haemagglutinating (Pv97, 9905 RHDVa). The specific immunological response was measured by the dynamics of changes in the amount of lymphocytes T (with CD5+, CD4+, CD8+, CD25+ receptor) and B (with CD19+ receptor). The study showed differences in immunogenicity of the analysed RHDV antigenic variants, which allowed them to be divided into groups of: more immunogenic strains, including non-haemagglutinating 9905 RHDVa and haemagglutinating Vt97 and Triptis variants; and less immunogenic strains, including the haemagglutinating Hartmannsdorf variant and the non-haemagglutinating Pv97 variant. Such a result may indicate that the agglutination capacity of red blood cells might not be a factor impacting the number of T and B lymphocytes

White and red blood cell picture in rabbits experimentally infected with strains of the rabbit haemorrhagic disease (RHD) virus without or with variable haemagglutination capacity

The aim of the study was to establish if haemagglutination of rabbit haemorrhagic disease virus (RHDV) affects haematological picture of peripheral blood in rabbits and the pathogenicity of the virus. The study analyzed white and red blood cell picture in rabbits experimentally infected with two non-haemagglutinating (HA-) RHDV strains (Frankfurt and Asturias) and one strain with variable haemagglutination capacity (HA+/−) (Hagenow). Studies with HA− and HA +/− are rare and relate only to 4 HA− strains (2 RHDV: BLA and Rainham; 2 RHDVa: Pv97 and 9905) and 1 HA+/− RHDV strain: ŻD, where less changes in haematological indices and less pathogenicity were observed. We found that changes caused by HA− Frankfurt strain were related to the number of neutrophils and thrombocytes, while in HA− strain Asturias, in thrombocytes and leukocytes. Changes evoked by HA+/− Hagenow strain pertained to the number of eosinophils, thrombocytes, leukocytes, monocytes, and concentration of hemoglobin. Mortality caused by the Frankfurt strain was 100% between 36 and 48 h post infection (p.i.), while that caused by Asturias strain was 100% between 24 and 36 h p.i., and that observed in case of Hagenow strain was 90% between 36 and 48 h p.i. The changes in haematological picture caused by the HA− and HA+/− RHDV strains were less intensive than those found in case of the HA+ RHDV strains, which cannot be confirmed for pathogenicity, and is not in line with the existing hypothesis suggesting higher pathogenicity in HA+ viruses

Apoptosis of granulocytes and lymphocytes in peripheral blood in rabbits infected with haemagglutinating and non-haemagglutinating antigenic variants of the RHD (rabbit haemorrhagic disease) virus

This paper attempts to study the dynamics of apoptosis of granulocytes and lymphocytes in peripheral blood in rabbits infected with haemagglutinating (Vt97, Triptis, Hartmannsdorf) and non-haemagglutinating (Pv97, 9905 RHDVa) antigenic variants of the RHD virus. The pathogenicity of those antigenic variants was also assessed by recording the mortality of the infected animals. The animals were infected with antigenic variants and blood was sampled at hour 0,4,8,12,24,36 p.i. and the percentage of apoptotic granulocytes and lymphocytes was measured with the use of flow cytometry. The results of the study showed that apoptosis is included during RHDV infection, as the number of apoptotic granulocytes and lymphocytes increases throughout the experiment; depending on the antigenic variant, apoptosis joins in at 4-8-12 h p.i. and lasts until 24-36 h p.i. Furthermore, the mortality of rabbits infected with the examined strains of RHD virus varied from 30% to 100%. This study performed for the first time in this manner, indicates the importance of apoptosis during infection with the RHD virus

Platelets – an important element of the immune system

Platelets are anucleate cells derived from the megakaryocyte series, and have long been considered only as cells responsible for coagulation and the fibrinolysis process. However, recently more data shows that they are also effector cells in the inflammatory response and important elements of the immunological response. Platelets store and release many biologically active substances, including growth factors, cytokines and chemokines (tab. 1), which actively affect i.a. elements of the immune system, and thus become regulators of immunity and mediators of inflammatory response. Their impact on the immune system cells is also associated with the induction of leucocytes and progenitor cells to the site of pathogen permeation or vascular injury inflow, as well as endothelial cells. Interacting with neutrophils, monocytes and lymphocytes, they not only activate them, but also form platelet-leukocyte aggregates that immobilise pathogens and prevent their spreading. Furthermore, platelets are capable of absorbing pathogens, affecting anti-infection immunity of the system. It is also assumed that the presence of receptors on their surface, such as Toll-like receptors (TLRs), affects their initiation and activity of the immunological response

Autophagy in physiological and pathological processes - selected aspects

This paper describes a model of cell death, called autophagy, one among other typical and atypical processes of cell death. This phenomenon is present in the organism, from conception until death, and is conditioned by many genes of ATG family, or mTOR kinase and specific proteins, like BNIP3. This process plays a very important role not only in physiological functions of the organism but also in pathological, such as Alzheimer or Huntington disease, as well as diseases caused by viruses

Real time PCR detection of rabbit haemorrhagic disease virus in rabbits infected with different European strains of RHDV

The paper concerns the use of a novel, very effective diagnostic method, a real-time PCR for diagnosis of a viral agent causing viral haemorrhagic disease in rabbits – RHDV. Until now, the method was widely used for detecting many different viruses, both DNA, and RNA, but as far as RHDV is concerned, there are not many records of such use. This study aimed at the detection of 17 different strains from different European regions, differing in biological features and mortality. The study confirmed that real-time PCR is an applicable and effective method for diagnosis of RHDV, irrespective of the stains’ features

B-cell and T-cell values in peripheral blood in Polish mixed-breed rabbits with addition of blood of meet breeds

In Poland, rabbit is a highly valued animal, due to dietetic and flavour values of its meat, but above all, rabbits tend to be commonly used laboratory animals. The aim of the study was developing standards for counts of B-cells with CD19+ receptor, T-cells with CD5+ receptor, and their subpopulations, namely T-cells with CD4+, CD8+ and CD25+ receptor in the peripheral blood of mixed-breed Polish rabbits with addition of blood of meet breeds, including the assessment of the impact of four seasons of the year and animal sex on the values of the immunological parameters determined. The results showed that the counts of B- and T-cells and their subpopulations in peripheral blood remain within the following ranges: for CD19+ B-cells: 1.05 - 3.05%, for CD5+ T-cells: 34.00 - 43.07%, CD4+ T-cells: 23.52 - 33.23%, CD8+ T-cells: 12.55 - 17.30%, whereas for CD25+ T-cells: 0.72 - 2.81%. As it comes to the season of the year, it was observed that it principally affects the values of CD25+ T-cells, while in the case of rabbit sex, more changes were found in females

Hematological parameters in Polish mixed breed rabbits with addition of meat breed blood in the annual cycle

In the paper we studied haematologic values,such as haemoglobin concentration, haematocrit value, thrombocytes, leucocytes: lymphocytes, neutrophils, basophils, eosinophils and monocytes in the pheral blood in Polish mixed-breeds with addition of meat breed blood in order to obtain the reference values which are until now not available for this animals. In studying this indices we took into consideration the impact of the season (spring, summer, autumn, winter), and sex of the animals. The studies have shown a high impact of the season of the year on those rabbits, but only in spring and summer. Moreover we observed that the sex has mean impact on the studied values of haematological parameters in those rabbits. According to our knowledge, this is the first paper on haematologic values in this widely used group of rabbits, so they may serve as reference values

Natural immunity factors in Polish mixed breed rabbits

Mixed-breed rabbits in Poland are widely used for diagnostic and scientific research and as utility animals, therefore there is a need to know their immunological status, as well as their haematological status. In this study natural immunity factors were analyzed in Polish mixed-breed rabbits and Polish mixed-breed rabbits with addition of blood of meet-breed, considering the impact of sex and season of the year (spring, summer, autumn, winter) using measurement of non-specific cellular and humoral immunity parameters in peripheral blood. The study has revealed that there is a variety between the two commonly used mixed-breed types of rabbits, especially when sex and season is concerned, which is crucial for using these animals in experiments

Values of apoptosis of lymphocytes and granulocytes in peripheral blood of Polish mixed-breed rabbits in the annual cycle

The objective of the study was to determine values of apoptosis for peripheral blood lymphocytes and granulocytes, including dependency on the season of the year, in Polish mixed-breed rabbits and in mixed-breed rabbits with the addition of blood of meat-breed rabbits. The study was carried out in four seasons of the year (spring, summer, autumn, winter) involving 120 Polish mixed-breed rabbits – group I, and 120 Polish mixed-breed rabbits with addition of meat-breed rabbit blood – group II. Assessment of apoptosis of lymphocytes and granulocytes was performed using as FACScan cytometer by Becton Dickinson with FACSDiva software (USA), using as ApoFluor®Green Caspase reagent kit (MP Biomedicals, USA) to detect the activity of the total caspase pool 1, 3, 4, 5, 6, 7, 8, 9 in granulocytes and lymphocytes of rabbit peripheral blood. The results for apoptosis of lymphocytes and granulocytes in peripheral blood in the animals investigated (group I and II) were subjected to statistical analysis with the t’Student test at p=0.05. It was noted that, in rabbits from group I, the values for apoptosis of lymphocytes were the highest in winter and autumn (36.02% and 31.24%, respectively), and the lowest in spring and summer (26.73% and 22.72%, respectively), whereas in the case of granulocytes the highest values were in summer and spring (14.69% and 12.95%, respectively), and the lowest in winter and autumn (8.16% and 8.57%, respectively). In mixed-breed rabbits with the addition of meat-breed blood (group II), the values for apoptosis of lympocytes were the highest in spring (29.13%), and the lowest in summer (25.43%); whereas in the case of granulocytes the highest values were in summer and spring (14.0% and 11.15%, respectively), and the lowest in autumn and winter (7.46% and 7.64%, respectively)