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P250 Reporting potential donor specific antibodies (DSAS) to aid clinicians’ choice of recipients for deceased donor kidney transplant
Abstracts / Human Immunology 78 (2017) 51–254
P249
IMPACTS ON AUTOMATED HLA TYPING METHOD FROM ENVIRONMENTAL FACTORS Rajesh Shah a, Chih-Hung Lai a, Debra D. Hiraki a, Daniel Ramon b, Dolly B. Tyan c, Marcelo Fernandez-Vina d. a Histocompatibility, Immunogenetics, and Disease Profiling Laboratory, Palo Alto, CA, United States; bStanford Blood Center HIDPL, Palo Alto, CA, United States; cStanford University, Palo Alto, CA, United States; dStanford University School of Medicine, Palo Alto, CA, United States. Aim: Many environmental factors could affect the machinery used for automation. A 39 day study evaluated the consistency of HLA typing results in a laboratory setting with HVAC (Heating, Ventilation and Air Conditioning) installed. Methods: Calibrated iSensix temperature and humidity sensors were used. The environmental data were obtained from iSensix web software (2012). All the Pre-PCR and post-PCR HLA SSO and NGS typing tests were conducted with robotic automation methods using Beckman Biomek, Eppendorf epMotion and One Lambda LABXpress. One donor sample serving as in-house control for SSO and NGS HLA typing was used for typing consistency analysis. A total of 29 SSO runs were performed and 17 NGS runs during the study period. Four previously typed proficiency samples were also retested for HLA typing consistency analysis. Results: Within the 39 day study period, the average relative humidity (RH) inside the pre-PCR room was 35.04%, ranging from 19.68 to 51.16%. Pre-PCR room average temperature was 24.2oC, ranging from 16.8 to 25.2oC. The post PCR room average RH was 32.24%, ranging from 12.34 to 50.02%. Pre-PCR room average temperature was 24.2oC, ranging from 23.8 to 25.2oC. SSO typing results from In-house control sample are 99.95% (186/187 tests) concordant. One sample was analyzed with outdated IMGT template. NGS typing results from 17 runs were 100% concordant. Typing results from the previous proficiency samples were also in 100% agreement. Conclusions: There are wide range of temperature and humidity requirements for optimal robotic machinery to operate. Most US buildings with HVAC will follow American Society of Heating, Refrigerating, and Air Conditioning Engineers (ASHRAE) guidelines. The ASHRAE guidelines recommend environmental condition is 68–74oF (20.0–23.3oC) in the winter and 72–80oF (22.2–26.6oC) in the summer with a RH of 30–60%. Our typing results concordance rate showed robotic automated HLA typing methods can withstand a wide range of environmental variations at our lab geographic location and elevation. Laboratory building with HVAC installed and operated following ASHRAE guidelines should have no issues obtaining a reliable HLA typing results using robotic automated typing methods.
D.B. Tyan: 2. Consultant; Company/Organization; One Lambda. M. Fernandez-Vina: 2. Consultant; Company/ Organization; Immucor.
P250
REPORTING POTENTIAL DONOR SPECIFIC ANTIBODIES (DSAS) TO AID CLINICIANS’ CHOICE OF RECIPIENTS FOR DECEASED DONOR KIDNEY TRANSPLANT Carley Shaut, Brent Gardner, Mike Drain, Lori Fletcher, Douglas J. Norman. Oregon Health & Science University, Portland, OR, United States. Aim: A virtual crossmatch determines which recipients are eligible for a deceased donor kidney based on UNET unacceptable antigens. The MFI threshold for unacceptable antigens is often higher than what most labs consider to be positive (e.g. 1000 MFI). Clinicians are interested in knowing whether DSAs below the threshold are present so immunosuppression protocols can be altered or, if several are present, they should rule out a patient for transplant. What is the mechanism for reporting to clinicians the presence of potential DSAs during deceased donor kidney allocation?. Methods: The Laboratory of Immunogenetics & Transplant (LIT) serves three kidney transplant centers and the local organ procurement organization. Waitlist patients are screened yearly by One Lambda Single Antigen I/II beads. Unacceptable antigen (UA) cutoffs are 3000-5000MFI, while single antigen beads >1000 MFI are assigned as positive with a few exceptions. During deceased donor evaluation, LIT technologists complete HLA-specific data entry into DonorNet and perform the matchrun. Using LIT-specific Histotrac programming, LIT runs exclusion algorithms for local protocols, choses the top candidates to crossmatch, and creates a Virtual XM report. Two centers use a protocol to avoid unacceptable antigens with additive MFIs >3000. We reviewed matchruns, virtual crossmatch exclusions, and transplants from March 2015 to Febuary 2017. Results: In two years of cases, 332 kidney matchruns were evaluated: 286 local matchruns were performed while 46 import donors were evaluated. Consequently, 2288 patient-donor pairs were reviewed by virtual crossmatch. Patients were ruled out due to additive DSAs in 17 (0.7%) patient-donor pairs. Two-thirds of patients who were transplanted with a deceased donor kidney had a 0% cPRA while 5% had cPRA 98–100%. Positive virtual crossmatches prompted additional review of UA and antibody history. Conclusions: The laboratory staff is responsible for completing deceased donor matchruns and generating a virtual crossmatch report, thus providing a streamlined approach to deceased donor evaluations. The virtual crossmatch report is essential for clinicians’ center-specific algorithms, induction protocols, and assessing risk for kidney candidates in the presence of potential DSA.
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P249
IMPACTS ON AUTOMATED HLA TYPING METHOD FROM ENVIRONMENTAL FACTORS Rajesh Shah a, Chih-Hung Lai a, Debra D. Hiraki a, Daniel Ramon b, Dolly B. Tyan c, Marcelo Fernandez-Vina d. a Histocompatibility, Immunogenetics, and Disease Profiling Laboratory, Palo Alto, CA, United States; bStanford Blood Center HIDPL, Palo Alto, CA, United States; cStanford University, Palo Alto, CA, United States; dStanford University School of Medicine, Palo Alto, CA, United States. Aim: Many environmental factors could affect the machinery used for automation. A 39 day study evaluated the consistency of HLA typing results in a laboratory setting with HVAC (Heating, Ventilation and Air Conditioning) installed. Methods: Calibrated iSensix temperature and humidity sensors were used. The environmental data were obtained from iSensix web software (2012). All the Pre-PCR and post-PCR HLA SSO and NGS typing tests were conducted with robotic automation methods using Beckman Biomek, Eppendorf epMotion and One Lambda LABXpress. One donor sample serving as in-house control for SSO and NGS HLA typing was used for typing consistency analysis. A total of 29 SSO runs were performed and 17 NGS runs during the study period. Four previously typed proficiency samples were also retested for HLA typing consistency analysis. Results: Within the 39 day study period, the average relative humidity (RH) inside the pre-PCR room was 35.04%, ranging from 19.68 to 51.16%. Pre-PCR room average temperature was 24.2oC, ranging from 16.8 to 25.2oC. The post PCR room average RH was 32.24%, ranging from 12.34 to 50.02%. Pre-PCR room average temperature was 24.2oC, ranging from 23.8 to 25.2oC. SSO typing results from In-house control sample are 99.95% (186/187 tests) concordant. One sample was analyzed with outdated IMGT template. NGS typing results from 17 runs were 100% concordant. Typing results from the previous proficiency samples were also in 100% agreement. Conclusions: There are wide range of temperature and humidity requirements for optimal robotic machinery to operate. Most US buildings with HVAC will follow American Society of Heating, Refrigerating, and Air Conditioning Engineers (ASHRAE) guidelines. The ASHRAE guidelines recommend environmental condition is 68–74oF (20.0–23.3oC) in the winter and 72–80oF (22.2–26.6oC) in the summer with a RH of 30–60%. Our typing results concordance rate showed robotic automated HLA typing methods can withstand a wide range of environmental variations at our lab geographic location and elevation. Laboratory building with HVAC installed and operated following ASHRAE guidelines should have no issues obtaining a reliable HLA typing results using robotic automated typing methods.
D.B. Tyan: 2. Consultant; Company/Organization; One Lambda. M. Fernandez-Vina: 2. Consultant; Company/ Organization; Immucor.
P250
REPORTING POTENTIAL DONOR SPECIFIC ANTIBODIES (DSAS) TO AID CLINICIANS’ CHOICE OF RECIPIENTS FOR DECEASED DONOR KIDNEY TRANSPLANT Carley Shaut, Brent Gardner, Mike Drain, Lori Fletcher, Douglas J. Norman. Oregon Health & Science University, Portland, OR, United States. Aim: A virtual crossmatch determines which recipients are eligible for a deceased donor kidney based on UNET unacceptable antigens. The MFI threshold for unacceptable antigens is often higher than what most labs consider to be positive (e.g. 1000 MFI). Clinicians are interested in knowing whether DSAs below the threshold are present so immunosuppression protocols can be altered or, if several are present, they should rule out a patient for transplant. What is the mechanism for reporting to clinicians the presence of potential DSAs during deceased donor kidney allocation?. Methods: The Laboratory of Immunogenetics & Transplant (LIT) serves three kidney transplant centers and the local organ procurement organization. Waitlist patients are screened yearly by One Lambda Single Antigen I/II beads. Unacceptable antigen (UA) cutoffs are 3000-5000MFI, while single antigen beads >1000 MFI are assigned as positive with a few exceptions. During deceased donor evaluation, LIT technologists complete HLA-specific data entry into DonorNet and perform the matchrun. Using LIT-specific Histotrac programming, LIT runs exclusion algorithms for local protocols, choses the top candidates to crossmatch, and creates a Virtual XM report. Two centers use a protocol to avoid unacceptable antigens with additive MFIs >3000. We reviewed matchruns, virtual crossmatch exclusions, and transplants from March 2015 to Febuary 2017. Results: In two years of cases, 332 kidney matchruns were evaluated: 286 local matchruns were performed while 46 import donors were evaluated. Consequently, 2288 patient-donor pairs were reviewed by virtual crossmatch. Patients were ruled out due to additive DSAs in 17 (0.7%) patient-donor pairs. Two-thirds of patients who were transplanted with a deceased donor kidney had a 0% cPRA while 5% had cPRA 98–100%. Positive virtual crossmatches prompted additional review of UA and antibody history. Conclusions: The laboratory staff is responsible for completing deceased donor matchruns and generating a virtual crossmatch report, thus providing a streamlined approach to deceased donor evaluations. The virtual crossmatch report is essential for clinicians’ center-specific algorithms, induction protocols, and assessing risk for kidney candidates in the presence of potential DSA.
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