Non-specific immunity in rabbits infected with 10 strains of the rabbit haemorrhagic disease virus with different biological properties

Research paper Indices of non-specific immunity: an element of natural immunity in rabbits infected with RHD (rabbit haemorrhagic disease) virus

“…In turn, as to the immunity measured using the parameters of non-specific humoral immunity, differentiation was also recorded among the strains analysed, whereas most changes were recorded for haemagglutinating French strain 05-01, while the remaining six strains (Austrian haemagglutinating 01-04, 237/04, V-12, Hungarian haemagglutinating 24V/89, 1447V/96, and Hungarian haemagglutinating antigenic variant 72V/2003) formed a group of strains causing fewer changes, which confirms previous observations of our team [2][3][4][10][11][12][13][14][15][16][17][18][19][20][21][22][23] evidencing the presence of immunotypes within RHDV. It must also be stated that in the present studies, no impact was recorded of such properties as the time and country of isolation of a particular RHDV strain on their immunogenicity, namely formation of immunogroups, similarly to haemagglutination capacity of RHDV, although previous studies [2,27] show that the latter property can be important for immunotype formation within RHDV. Furthermore, the results of the present study indicate that the only analysed antigenic variant 72V/2003 of RHDV caused a different image of the analysed indices as compared to the remaining six currently analysed strains of RHDV, as only decreases in the parameters analysed were observed, which confirms prior studies by our team [2][3][4][10][11][12][13][14][15][16][17][18][19][20][21][22][23] on the biology of antigenic variants of RHDV.…”

“…The present study was to complete the immunological image of RHDV strains with new data, concerning new, non-analysed in this aspect, 7 strains of RHDV. It must be stated that the results of immunological studies regarding 24 strains of RHDV, including two haemagglutinating French strains (Fr-1, Fr-2) [2,4,18,20] and one non-haemagglutinating antigenic variant 9905 RHDVa) [16,27], seven haemagglutinating Polish strains (SGM, MA£, KGM,¯D, PD, GSK, Kr-1) and one non-haemagglutinating one (BLA) [2,4,14,19,22,23], four haemagglutinating Czech strains (CAMP V-351, CAMP V-561, CAMP V-562, CAMP V-558) [12,13,23], three Italian strains (haemagglutinating BS89 and antigenic variants -haemagglutinating Vt97 and non-haemagglutinating Pv97), one English non-haemagglutinating Rainham strain, four German strains (Hagenow with variable haemagglutination capacity, haemagglutinating antigenic variants Triptis and Hartmannsdorf, and nonhaemagglutinating Frankfurt), and one Spanish non-haemagglutinating Asturias strain [17,21,22,27], confirm that the diverse immunogenicity among such RHDV strains not only depends on the year and country of isolation, but also on biological properties, namely haemagglutination capacity, or formation of antigenic variants. This proves that the results can provide the basis for differentiation of immunotypes among such RHDV strains.…”

“…These strains, in the form of liver homogenate, were used for experimental infection of rabbits, from which liver was sampled after death. Next, it was prepared as 20% homogenate purified by centrifugation at 3000 rpm, 10% chloroforming for 60 minutes, and centrifugation again, and next by suspension in glycerol at the ratio of 1 : 1 [27]. All antigens prepared had the same number of viral particles determined with buoyant density in caesium chloride, within the limits of 1.34 g/dm 3 [27].…”

Phagocytosis of neutrophils in rabbits infected with antigenic variants of RHD (rabbit haemorrhagic disease) virus

“…: 4, 8, 52-60 h, although in many cases the changes were also observed in the 12 th , 24 th , 36 th and 48 th hour. In each of the study mentioned, these changes were noted shortly before the death of animals, which occurred 52-60 h after RHDV infection (Piekarski 1994, Hukowska-Szematowicz 2006, Tokarz-Deptuła et al 2007, Niedźwiedzka et al 2008, Tokarz-Deptuła 2009, or 24-36 h after administration of the virus in case of experiments of Niedźwiedzka--Rystwej and Deptuła (2010).…”

Natural immunity factors in Polish mixed breed rabbits

“…In blood, parameters of natural immunity measured by parameters of non-specific cellular and humoral immunity were investigated, according to the methods descried before (Niedźwiedzka-Rystwej and Deptuła 2010). All the results were subjected to statistical analysis with Student t test in the Statistica software version 6.0 (StatSoft, Poland) and are shown in Tables 1-4.…”