1. Sean Doyle National University of Ireland, Maynooth, Ireland. Parvovirus B19 Infection in Seronegative and Seropositive Individuals – Implications for Blood Product Safety. Bern, Switzerland. 15 June 2006.

2. PARVOVIRUS B19 Capsid Proteins: B19 VP1 and VP2 (70% identical). Capsid VP2 is the main protein used for antibody detection. VP2-N v VP2-D.

3. Individual Apparent Infectious Ref. Dose (B19 DNA) Female, 36 yr SD Plasma (10 7 -10 8 GE/ml)Koenigbauer et al. 2000: Transfusion. Male, 16 mo. B19 IgG- plasma protein Blumel et al. complex 2002: Transfusion. 8.6 x 10 6 GE/ml (180 ml)) 1.5 x 10 9 GE Male, 5yrB19 IgG- plasma protein Blumel et al. complex 2002: Transfusion. 4 x 10 3 GE/ml (996 ml)) 3.9 x 10 6 GE Male, 47 yrB19 IgG- Wu et al. Factor VIII Concentrate 2005: Transfusion. (1.3 x 10 3 IU/ml) 2 x 10 4 IU Incidences of Parvovirus B19 Transmission

4. Retrospective study of similar plasma pools (n = 30). B19 IgG levels : 65 + 18 IU/ml. B19 IgG may be capable of preventing recipient B19 infection when transfused with plasma contaminated with low levels of parvovirus B19 (< 10 4 GE/ml). Daly et al. 2002: J. Clin Microbiol. Pooled SD plasma administration 100 volunteers > 10 7 GE/ml=> B19 seroconversion No seroconversion Davenport et al. 2000: Blood. Brown et al. 2002: Transfusion. Incidences of Parvovirus B19 Transmission

5. B19 IgG……….Protective Effect? B19 IgG+ Blood Products. B19 DNA Levels: 6 x 10 2 –2.2 x 10 6 GE/ml. Individual Recipients (n = 14)…… -> No Symptoms or B19 Seroconversion. Plentz et al. 2005: Transfusion.

6. Some outstanding questions……… 1. Does B19 IgG presence minimise the risk of infection with B19 contaminated materials? 2. How do B19 seropositive individuals respond to re-exposure the virus? 4. B19 IgG reactivity against linear epitopes of VP2- A marker of recent infection? (Soderlund et al. 1995). 3. What is the protective level of B19 IgG which may prevent re-infection?

7. Group No. Plasma pool ID (B19 DNA (IU)) Recipient Code(Daly et al. 2002: J. Clin Microbiol.) Group I (SP) 01002PS3 (3.2 x 10 10 ) 01052N.A. 01098PS3 (3.2 x 10 10 ) Group II (SN) 01023PS2A (10 3.5 GE/ml) ~ 7 x 10 4 IU 01053PS2A (10 3.5 GE/ml) 01055N.A. Group III (SN-SC) 01005PS1 (4.4 x 10 10 ) 01048PS1 (4.4 x 10 10 ) 01057PS1 (4.4 x 10 10 ) 01069PS3 (3.2 x 10 10 ) Doyle and Corcoran, 2006: J Infect. Dis. Specimen and Plasma Pool Details B19 IgG levels 72 IU/ml B19 IgG 59 IU/ml B19 IgG 65 + 18 IU/ml B19 IgG

8. 1. B19 IgM Detection2. B19 IgG Detection VP2-N 3. B19 IgG Detection VP1-N Seroconversion Profiles –1/2 Doyle and Corcoran, 2006: J. Infect. Dis. I I II III I

9. 4. B19 IgG Detection (VP1-D) 5. B19 IgG Detection (VP2-D) Seroconversion Profiles –2/2 Doyle and Corcoran, 2006: J. Infect. Dis. IIII III

10. Conclusions & Implications… 1. B19 IgG seropositive individuals do not exhibit symptoms of re-infection- even at high IU B19 DNA. 2. B19 IgG [VP2-N] levels of 19 IU/ml prevent sero- positive recipient re-infection & B19 IgG levels rise in response to repeat exposure (except B19 IgG [VP2-D]). 3. B19 IgG (65 + 18 IU/ml) appear to prevent B19 transmission to seronegative recipients at levels of < 7 x 10 4 IU B19 DNA in SD plasma. 4. High levels of B19 IgG cannot prevent recipient infection in the presence of 3.2 –4.4 x 10 10 IU B19 DNA. 5. B19 IgG [VP2-D]- marker of recent exposure.

11. Plasma cell APC Activated Th cell CD4 B19-specific Ig Appears 10 days post-infection VP1-N VP1-D VP2-N VP2-D NS1-N IgM Appears 15 days post-infection VP1-N lifelong VP1-D declines slowly VP2-N lifelong VP2-D disappears within 6 months NS1 associated with acute & persistent infection IgG Chronic B19 infection-inability to produce neutralizing antibodies B19 infection Memory B cell IL-1  IL-6Joint inflammation in RA IFN-  Suppressed during pregnancy IL-2 Present at maternal-fetal interface TNF-  IL-8 B19 associated cytokines B cell memory Established against VP2-N VP1-N VP1-D

12. Contributors and colleagues: Amanda Corcoran Paul Daly EU 5 th Framework ‘Parvovirus’ Consortium QLK2-CT-00877. QUALITY OF LIFE AND MANAGEMENT OF LIVING RESOURCES sean.doyle@nuim.ie