PMID- 17215336
OWN - NLM
STAT- MEDLINE
DCOM- 20070925
LR  - 20220331
IS  - 1556-6811 (Print)
IS  - 1556-679X (Electronic)
IS  - 1556-679X (Linking)
VI  - 14
IP  - 3
DP  - 2007 Mar
TI  - Protection against porcine reproductive and respiratory syndrome virus (PRRSV) 
      infection through passive transfer of PRRSV-neutralizing antibodies is dose 
      dependent.
PG  - 269-75
AB  - Previous work in our laboratory demonstrated that passive transfer of porcine 
      reproductive and respiratory syndrome virus (PRRSV)-neutralizing antibodies (NA) 
      protected pregnant sows against reproductive failure and conferred sterilizing 
      immunity in sows and offspring. We report here on the dose requirement for 
      protection by passive transfer with NA in young weaned pigs. The presence of a 
      1:8 titer of PRRSV-NA in serum consistently protected pigs against viremia. 
      Nevertheless, their lungs, tonsils, buffy coat cells, and peripheral lymph nodes 
      contained replicating PRRSV similar to the infected control group. Likewise, 
      these animals excreted infectious virus to sentinels similar to the infectivity 
      control animals. In an attempt to reach complete protective immunity equivalent 
      to that previously observed in sows, the pigs were transferred with a higher 
      titer of PRRSV-NA (1:32), and even then apparent sterilizing immunity was 
      attained in only 50% of the animals. In conclusion, the presence of anti-PRRSV-NA 
      in serum with a titer of 1:8 is enough to block viremia but not peripheral tissue 
      seeding and transmission to contact animals. While a relatively low level of NA 
      in blood is capable of conferring sterilizing immunity against PRRSV in sows, the 
      amount of NA necessary to obtain full protection of a young weaned pig would be 
      significantly higher, suggesting that differences exist in the PRRSV pathogenesis 
      between both age groups. In addition, the titer of NA could be a helpful 
      parameter of protection in the assessment of PRRSV vaccines.
FAU - Lopez, O J
AU  - Lopez OJ
AD  - Department of Veterinary and Biomedical Sciences, University of Nebraska, 141 
      VBS, East Campus, Lincoln, NE 68583-0905, USA.
FAU - Oliveira, M F
AU  - Oliveira MF
FAU - Garcia, E Alvarez
AU  - Garcia EA
FAU - Kwon, B J
AU  - Kwon BJ
FAU - Doster, A
AU  - Doster A
FAU - Osorio, F A
AU  - Osorio FA
LA  - eng
PT  - Journal Article
PT  - Research Support, Non-U.S. Gov't
PT  - Research Support, U.S. Gov't, Non-P.H.S.
DEP - 20070110
PL  - United States
TA  - Clin Vaccine Immunol
JT  - Clinical and vaccine immunology : CVI
JID - 101252125
RN  - 0 (Antibodies, Viral)
SB  - IM
MH  - Animals
MH  - Antibodies, Viral/*immunology
MH  - Dose-Response Relationship, Immunologic
MH  - *Immunization, Passive
MH  - Lung/virology
MH  - Porcine Reproductive and Respiratory Syndrome/*prevention & 
      control/transmission/virology
MH  - Porcine respiratory and reproductive syndrome virus/*immunology
MH  - Swine
MH  - Viremia/virology
MH  - Virus Replication
MH  - Virus Shedding
PMC - PMC1828847
EDAT- 2007/01/12 09:00
MHDA- 2007/09/26 09:00
PMCR- 2007/07/01
CRDT- 2007/01/12 09:00
PHST- 2007/01/12 09:00 [pubmed]
PHST- 2007/09/26 09:00 [medline]
PHST- 2007/01/12 09:00 [entrez]
PHST- 2007/07/01 00:00 [pmc-release]
AID - CVI.00304-06 [pii]
AID - 0304-06 [pii]
AID - 10.1128/CVI.00304-06 [doi]
PST - ppublish
SO  - Clin Vaccine Immunol. 2007 Mar;14(3):269-75. doi: 10.1128/CVI.00304-06. Epub 2007 
      Jan 10.