- Email: [email protected]
P200 High-resolution HLA typing of deceased donors enables accurate identification of allle_specific DSA
Abstracts / Human Immunology 78 (2017) 51–254
P199
A SUCCESSFUL LUNG TRANSPLANTATION IN TWO PATIENTS WITH POSITIVE DONOR SPECIFIC ANTIBODIES AND POSITIVE CROSSMATCH Samar Shadly, Imran Nizami, Waleed Saleh, Mohammed Ahmed, Khaled Al Kattan, Fadi Alzayer, Amal Algharabli, Moheeb Al-Awwami. King Faisal specialist Hospital & Research Center, Riyadh, Saudi Arabia. Introduction: Sensitization to HLA antibodies has been associated with worse outcome in lung transplant recipients. Many lung transplant centers avoid transplanting patients with positive flow cytometry crossmatch (FCXM). However, delaying the transplant in these patients may increase their mortality on the waiting list. We are reporting two cases of crossmatch positive lung transplantation. Case scenario: A 37-year old lady diagnosed with pulmonary fibrosis. Patient sensitized to HLA class I and II at time of transplant.The FCXM was positive T-cell (+78 MCS) and B-cell (+165 MCS). She had multiple DSA: Anti A2 (2795 MFI), Anti DR51 (2215 MFI), Anti DR52 (2088 MFI), Anti DQB1:05:02 (655 MFI), Anti DR14 (1411 MFI), anti DP2 (813 MFI). Second case is a 58-year old lady with pulmonary fibrosis secondary to Sjogren’s syndrome. Patient sensitized to HLA class II only at the time of transplant. The T-cell crossmatch was negative while, B-cell was positive (+318 MCS). She had multiple DSA: Anti DRB1⁄ 10:01(14776 MFI), Anti-DR53 (4796 MFI), Anti-DP1 (1942 MFI), Anti- DQB1⁄ 05:01(3384 MFI), Anti-DP2 (790 MFI). In view of patients’ deterioration, lung transplantation was preceded despite of positive crossmatch results, using combination of plasmapheresis, Intravenous immunoglobulin (IVIG) and Thymoglobulin. Both patients did well with no evidence of graft rejection. However, the repeated HLA antibodies screening during follow up showed persistent DSA. in the first patient: Anti-A2(1377 MFI), Anti-DRB1⁄ 14 (4864 MFI), Anti-DR52 (3044 MFI), Anti-DR51 (1708 MFI), Anti-DP2 (1993 MFI). In the second patient: Anti-A1 (3561 MFI), AntiA24 (712 MFI), Anti-DQB1⁄ 05:01(5837 MFI), Anti-DP1 (692 MFI), Anti-DRB1⁄ 10:01 (643 I). Conclusion: Lung transplantation is possible in patients with crossmatch positive, using perioperative desensitization protocol. Desensitization treatment did neither eliminate DSA nor prevent de novo DSA formation. However, follow up of these patients showed no evidence of graft rejection. Long-term data is needed.
P200
HIGH-RESOLUTION HLA TYPING OF DECEASED DONORS ENABLES ACCURATE IDENTIFICATION OF ALLLE_SPECIFIC DSA Bing Yang a, Chunlong Yang b, Elizabeth Ingulli c, Gerald P. Morris c. aUCSD Health System, San DIego, CA, United States; bUC San Diego Health System, San Diego, CA, United States; cUniversity of California, San Diego, CA, United States. HLA typing of donors for solid organ transplantation is performed with the primary goal of avoiding hyperacute antibody-mediated rejection (AMR) caused by recipient antibodies against donor antigens. Given the need for rapid testing of deceased donors, SSP or SSO methods are used to enable timely HLA typing at the serologic split antigen level. However, these methods do not provide unambiguous allele-level genotyping. This ambiguity can be problematic in patients with allele-specific anti-HLA antibodies. We report a case of suspected AMR following deceased donor kidney transplantation as an example of high-resolution HLA genotyping enabling identification of donor-specific antibodies (DSA). The patient was transplanted in 2010 with a flow cytometric crossmatch negative deceased donor kidney. History was remarkable for biopsy-proven C4d positive acute AMR in 2012 successfully treated by IVIG and rituximab. In late 2016, the patient developed increased proteinuria. Biopsy demonstrated changes consistent with both active and chronic AMR, but without presence of C4d. Solid-phase anti-HLA antibody testing did not demonstrate identifiable DSA, though there was evidence of allele-specific antibodies (Table 1). To investigate whether these represented DSA, donor DNA was re-typed for HLA-A, -B, -C, -DRB1, -DRB3/4/5, -DQA1, -DQB1, -DPA1,and -DPB1 by next-generation DNA sequencing (NGS). High-resolution HLA typing identified DSA against DQA1⁄ 05:05 and DRB3⁄ 03:01. Reactivity against DR52 or DQA05 would not have been called based upon average group reactivity. Identification of DSA supported diagnosis of AMR and enabled tracking of DSA as an objective measure of the efficacy of therapy. The increasing frequency of allele-specific DSA has led us to implement routine re-testing of solid organ donors for high-resolution HLA typing to promote accurate and efficient evaluation of potential allele-specific DSA.
Table 1. Allele-specific antibody reactivity HLA Allele
Normalized MFI
DRB3*01:01
441
DRB3*02:02
656
DRB3*03:01
2485
DQA1*05:01
7223
DQA1*05:03
1215
DQA1*05:05
782
205
P199
A SUCCESSFUL LUNG TRANSPLANTATION IN TWO PATIENTS WITH POSITIVE DONOR SPECIFIC ANTIBODIES AND POSITIVE CROSSMATCH Samar Shadly, Imran Nizami, Waleed Saleh, Mohammed Ahmed, Khaled Al Kattan, Fadi Alzayer, Amal Algharabli, Moheeb Al-Awwami. King Faisal specialist Hospital & Research Center, Riyadh, Saudi Arabia. Introduction: Sensitization to HLA antibodies has been associated with worse outcome in lung transplant recipients. Many lung transplant centers avoid transplanting patients with positive flow cytometry crossmatch (FCXM). However, delaying the transplant in these patients may increase their mortality on the waiting list. We are reporting two cases of crossmatch positive lung transplantation. Case scenario: A 37-year old lady diagnosed with pulmonary fibrosis. Patient sensitized to HLA class I and II at time of transplant.The FCXM was positive T-cell (+78 MCS) and B-cell (+165 MCS). She had multiple DSA: Anti A2 (2795 MFI), Anti DR51 (2215 MFI), Anti DR52 (2088 MFI), Anti DQB1:05:02 (655 MFI), Anti DR14 (1411 MFI), anti DP2 (813 MFI). Second case is a 58-year old lady with pulmonary fibrosis secondary to Sjogren’s syndrome. Patient sensitized to HLA class II only at the time of transplant. The T-cell crossmatch was negative while, B-cell was positive (+318 MCS). She had multiple DSA: Anti DRB1⁄ 10:01(14776 MFI), Anti-DR53 (4796 MFI), Anti-DP1 (1942 MFI), Anti- DQB1⁄ 05:01(3384 MFI), Anti-DP2 (790 MFI). In view of patients’ deterioration, lung transplantation was preceded despite of positive crossmatch results, using combination of plasmapheresis, Intravenous immunoglobulin (IVIG) and Thymoglobulin. Both patients did well with no evidence of graft rejection. However, the repeated HLA antibodies screening during follow up showed persistent DSA. in the first patient: Anti-A2(1377 MFI), Anti-DRB1⁄ 14 (4864 MFI), Anti-DR52 (3044 MFI), Anti-DR51 (1708 MFI), Anti-DP2 (1993 MFI). In the second patient: Anti-A1 (3561 MFI), AntiA24 (712 MFI), Anti-DQB1⁄ 05:01(5837 MFI), Anti-DP1 (692 MFI), Anti-DRB1⁄ 10:01 (643 I). Conclusion: Lung transplantation is possible in patients with crossmatch positive, using perioperative desensitization protocol. Desensitization treatment did neither eliminate DSA nor prevent de novo DSA formation. However, follow up of these patients showed no evidence of graft rejection. Long-term data is needed.
P200
HIGH-RESOLUTION HLA TYPING OF DECEASED DONORS ENABLES ACCURATE IDENTIFICATION OF ALLLE_SPECIFIC DSA Bing Yang a, Chunlong Yang b, Elizabeth Ingulli c, Gerald P. Morris c. aUCSD Health System, San DIego, CA, United States; bUC San Diego Health System, San Diego, CA, United States; cUniversity of California, San Diego, CA, United States. HLA typing of donors for solid organ transplantation is performed with the primary goal of avoiding hyperacute antibody-mediated rejection (AMR) caused by recipient antibodies against donor antigens. Given the need for rapid testing of deceased donors, SSP or SSO methods are used to enable timely HLA typing at the serologic split antigen level. However, these methods do not provide unambiguous allele-level genotyping. This ambiguity can be problematic in patients with allele-specific anti-HLA antibodies. We report a case of suspected AMR following deceased donor kidney transplantation as an example of high-resolution HLA genotyping enabling identification of donor-specific antibodies (DSA). The patient was transplanted in 2010 with a flow cytometric crossmatch negative deceased donor kidney. History was remarkable for biopsy-proven C4d positive acute AMR in 2012 successfully treated by IVIG and rituximab. In late 2016, the patient developed increased proteinuria. Biopsy demonstrated changes consistent with both active and chronic AMR, but without presence of C4d. Solid-phase anti-HLA antibody testing did not demonstrate identifiable DSA, though there was evidence of allele-specific antibodies (Table 1). To investigate whether these represented DSA, donor DNA was re-typed for HLA-A, -B, -C, -DRB1, -DRB3/4/5, -DQA1, -DQB1, -DPA1,and -DPB1 by next-generation DNA sequencing (NGS). High-resolution HLA typing identified DSA against DQA1⁄ 05:05 and DRB3⁄ 03:01. Reactivity against DR52 or DQA05 would not have been called based upon average group reactivity. Identification of DSA supported diagnosis of AMR and enabled tracking of DSA as an objective measure of the efficacy of therapy. The increasing frequency of allele-specific DSA has led us to implement routine re-testing of solid organ donors for high-resolution HLA typing to promote accurate and efficient evaluation of potential allele-specific DSA.
Table 1. Allele-specific antibody reactivity HLA Allele
Normalized MFI
DRB3*01:01
441
DRB3*02:02
656
DRB3*03:01
2485
DQA1*05:01
7223
DQA1*05:03
1215
DQA1*05:05
782
205