PMID- 12414926
OWN - NLM
STAT- MEDLINE
DCOM- 20021213
LR  - 20240413
IS  - 0022-538X (Print)
IS  - 1098-5514 (Electronic)
IS  - 0022-538X (Linking)
VI  - 76
IP  - 23
DP  - 2002 Dec
TI  - Comparison of molecular and biological characteristics of a modified live porcine 
      reproductive and respiratory syndrome virus (PRRSV) vaccine (ingelvac PRRS MLV), 
      the parent strain of the vaccine (ATCC VR2332), ATCC VR2385, and two recent field 
      isolates of PRRSV.
PG  - 11837-44
AB  - The objectives of this study were to compare the molecular and biological 
      characteristics of recent porcine reproductive and respiratory syndrome virus 
      (PRRSV) field isolates to those of a modified live virus (MLV) PRRS vaccine and 
      its parent strain. One hundred seventeen, 4-week-old pigs were randomly assigned 
      to six groups. Group 1 (n = 20) served as sham-inoculated negative controls, 
      group 2 (n = 19) was inoculated with Ingelvac PRRS MLV vaccine, group 3 (n = 20) 
      was inoculated with the parent strain of the vaccine (ATCC VR2332), group 4 (n = 
      19) was inoculated with vaccine-like PRRSV field isolate 98-38803, group 5 (n = 
      19) was inoculated with PRRSV field isolate 98-37120, and group 6 (n = 20) was 
      inoculated with known high-virulence PRRSV isolate ATCC VR2385. The levels of 
      severity of gross lung lesions (0 to 100%) among the groups were significantly 
      different at both 10 (P < 0.0001) and 28 days postinoculation (p.i.) (P = 0.002). 
      At 10 days p.i., VR2332 (26.5% +/- 4.64%) and VR2385 (36.4% +/- 6.51%) induced 
      gross lesions of significantly greater severity than 98-38803 (0.0% +/- 0.0%), 
      98-37120 (0.8% +/- 0.42%), Ingelvac PRRS MLV (0.9% +/- 0.46%), and negative 
      controls (2.3% +/- 1.26%). At 28 days p.i., 98-37120 (17.2% +/- 6.51%) induced 
      gross lesions of significantly greater severity than any of the other viruses. 
      Analyses of the microscopic-interstitial-pneumonia-lesion scores (0 to 6) 
      revealed that VR2332 (2.9 +/- 0.23) and VR2385 (3.1 +/- 0.35) induced 
      significantly more severe lesions at 10 days p.i. At 28 days p.i., VR2385 (2.5 
      +/- 0.27), VR2332 (2.3 +/- 0.21), 98-38803 (2.6 +/- 0.29), and 98-37120 (3.0 +/- 
      0.41) induced significantly more severe lesions than Ingelvac PRRS MLV (0.7 +/- 
      0.17) and controls (0.7 +/- 0.15). The molecular analyses and biological 
      characterizations suggest that the vaccine-like isolate 98-38803 (99.5% amino 
      acid homology based on the ORF5 gene) induces microscopic pneumonia lesions 
      similar in type to, but different in severity and time of onset from, those 
      observed with virulent strains VR2385 and the parent strain of the vaccine. Our 
      data strongly suggest that isolate 98-38803 is a derivative of Ingelvac PRRS MLV 
      and that the isolate is pneumovirulent.
FAU - Opriessnig, T
AU  - Opriessnig T
AD  - Department of Veterinary Diagnostic and Production Animal Medicine, College of 
      Veterinary Medicine, Iowa State University, Ames, Iowa 50011, USA.
FAU - Halbur, P G
AU  - Halbur PG
FAU - Yoon, K-J
AU  - Yoon KJ
FAU - Pogranichniy, R M
AU  - Pogranichniy RM
FAU - Harmon, K M
AU  - Harmon KM
FAU - Evans, R
AU  - Evans R
FAU - Key, K F
AU  - Key KF
FAU - Pallares, F J
AU  - Pallares FJ
FAU - Thomas, P
AU  - Thomas P
FAU - Meng, X J
AU  - Meng XJ
LA  - eng
SI  - GENBANK/AF535152
PT  - Comparative Study
PT  - Journal Article
PT  - Research Support, Non-U.S. Gov't
PL  - United States
TA  - J Virol
JT  - Journal of virology
JID - 0113724
RN  - 0 (Antibodies, Viral)
RN  - 0 (RNA, Viral)
RN  - 0 (Viral Vaccines)
SB  - IM
MH  - Animals
MH  - Antibodies, Viral/biosynthesis
MH  - Lung/pathology
MH  - Molecular Sequence Data
MH  - Phylogeny
MH  - Porcine Reproductive and Respiratory Syndrome/*immunology/pathology/*prevention & 
      control/virology
MH  - Porcine respiratory and reproductive syndrome 
      virus/*genetics/*immunology/isolation & purification/pathogenicity
MH  - RNA, Viral/genetics
MH  - Swine
MH  - Viral Vaccines/*genetics
MH  - Virulence/genetics
PMC - PMC136866
EDAT- 2002/11/05 04:00
MHDA- 2002/12/17 04:00
PMCR- 2002/12/01
CRDT- 2002/11/05 04:00
PHST- 2002/11/05 04:00 [pubmed]
PHST- 2002/12/17 04:00 [medline]
PHST- 2002/11/05 04:00 [entrez]
PHST- 2002/12/01 00:00 [pmc-release]
AID - 0725 [pii]
AID - 10.1128/jvi.76.23.11837-11844.2002 [doi]
PST - ppublish
SO  - J Virol. 2002 Dec;76(23):11837-44. doi: 10.1128/jvi.76.23.11837-11844.2002.