Distribution of Anti-ABO Immunoglobulin G Subclass and C1q Antibody in ABO-incompatible Kidney Transplantation.

INTRODUCTION: To investigate the correlation between serum anti-ABO immunoglobulin G (IgG) and IgG subclasses, anti-ABO IgG subclasses were measured by flow cytometry (FCM) in ABO-incompatible (ABOi) kidney transplant recipients. We also evaluated baseline anti-ABO C1q antibody. METHOD: Baseline anti-ABO IgG titers were measured by both FCM and column agglutination technique methods in 18 ABOi kidney transplant recipients. The mean florescence intensity (MFI) ratios of baseline anti-ABO IgG subclasses and anti-ABO C1q antibody were obtained by FCM and followed-up after rituximab treatment, each plasmapheresis (PP) session, and kidney transplantation. Correlation between the values of IgG subclass and total IgG titer was analyzed. RESULTS: The baseline MFI ratios of total IgG, IgG1, IgG2, IgG3, and IgG4 were 202.46, 62.41, 30.01, 1.04, and 1.13, respectively. The MFI ratios of IgG1, IgG2, and total IgG measured at baseline and pre-PP were positively correlated with the baseline ABO titer was measured using the column agglutination technique. The numbers of PP sessions to reach the target titer were correlated with the baseline IgG and IgG1 levels. IgG1 and IgG2 as well as total IgG were removed effectively after serial PP. Anti-ABO C1q antibody was neither detected nor correlated with total IgG and any IgG subclasses. CONCLUSIONS: Our findings suggest that IgG1 and IgG2 are the dominant IgG subclass in ABOi kidney transplant recipients. Baseline levels of IgG1 and IgG2 were correlated with baseline total IgG titer. However, anti-ABO C1q antibody was not detected in the present study.

A novel analysis strategy for HLA typing using a sequence-specific oligonucleotide probe method.

The technique of reverse sequence-specific oligonucleotide probes (SSOPs) is commonly used in human leukocyte antigen (HLA) typing. In the conventional method for data analysis (exact pattern matching, EPM), the larger is the number of mismatched probes, the longer the time for final typing assignment. A novel strategy, filtering and scoring (FnS), has been developed to easily assign the best-fit allele pair. In the FnS method, candidate alleles and allele pairs were filtered based on (1) subject's ethnicity, and (2) the measured partial reaction pattern with only definitely negative or positive probes. Then, the complete reaction pattern for all probes (CRPoAPs) were compared between the raw sample and expected residual allele pairs to obtain mismatch scores. To compare the FnS and EPM methods, each analysis time (minutes:seconds) for reverse SSOP HLA typing with intermediate resolution (n = 507) was measured. The analysis time with FnS method was shorter than that of the EPM method [00:21 (00:08-01:47) and 01:04 (00:15-23:45), respectively, P < .05]. In addition, the analysis time of the FnS method was relatively constant, regardless of the number of mismatched probes. The alternative approach of filtering based only on definite probes (neglecting ethnicity) took a long time for analysis. However, this approach did not compromise the accuracy. The FnS method showed improved accuracy and efficiency of HLA typing in a comprehensive and quantitative comparison between measured and expected CRPoAPs of candidate allele pairs. Therefore, this analysis strategy might be useful in a clinical setting.

Identification of a novel HLA-B*15 variant, B*15:367, using sequence-based typing in a Korean woman.

New allele, B*15:367, differs from B*15:11:01 by a single nucleotide exchange at codon 222 (GAG→AAG).

Application of flow cytometry to measure anti-A/B antibody in ABO-incompatible kidney transplantation.

BACKGROUND: The aim of this study was to compare anti-ABO antibody levels as measured by means of flow cytometry (FCM) with the levels measured with the use of the column agglutination test (CAT), and to evaluate the clinical outcome as it relates to the baseline mean fluorescence intensity (MFI) ratio obtained by FCM. METHODS: We reviewed 21 cases of ABO-incompatible kidney transplantation (ABO-i KT). In these patients, baseline IgG titers were measured with the use of both FCM and CAT methods. We investigated the correlation between levels measured by FCM and those by CAT with the use of correlation coefficients. Patients were classified into a high MFI ratio group (≥200; n = 7) or low MFI ratio group (<200; n = 14). RESULTS: The MFI ratio for the FCM-based method was highly correlated with the titer measured by CAT (r = 0.890; P = .01). The relationship between MFI ratio and CAT titer can be expressed as follows: log (MFI ratio) = 0.879 × log (CAT titer) + 0.298. The number of pre-transplantation rounds of plasmapheresis significantly increased as the baseline MFI ratio increased. The allograft function was immediately recovered and stable. A single case of acute cellular rejection was observed in the low MFI ratio group. CONCLUSIONS: Anti-ABO antibody levels measured by means of the FCM-based method were highly correlated with the levels measured with the use of CAT in cases of ABO-i KT. The decreased level of anti-ABO antibody measured by means of FCM after plasmapheresis suggests its potential as an effective and objective method for assessment of anti-ABO antibody levels.

HLA gene dosage effect on renal allograft survival.

BACKGROUND: Human leukocyte antigen (HLA)-A, HLA-B, and HLA-DR matching has beneficial long-term effects on renal allograft survival. However, the gene dosage effect of mismatched HLA on transplant outcomes is not known. We investigated the HLA gene dosage effects on allograft survival in kidney transplant recipients (KTRs). METHODS: We analyzed HLA typing of KTRs and kidney donors at Kyungpook National University Hospital from January 1982 to December 2012. KTRs were divided into 2 groups: recipients from homozygous HLA donors and recipients from heterozygous HLA donors. Death-censored graft survival of KTRs was compared according to allele state of kidney donors. RESULTS: In this study, 697 KTRs were enrolled. According to Kaplan-Meier analysis, graft survival in KTRs of HLA-DR and HLA-B heterozygous donors was longer than that in KTRs of HLA-DR and HLA-B homozygous donors (P = .007 and P < .0001, respectively). Multivariate Cox proportional hazards model analysis showed that HLA-DR and HLA-B donor homozygosity was an independent risk factor for death-censored graft survival (P = .019 and P = .022, respectively). Death-censored graft survival was not associated with HLA-A and HLA-A, B, DR allele states. CONCLUSIONS: Compared with HLA donor mismatch caused by HLA-DR and HLA-B heterozygosity, HLA donor mismatch caused by HLA-DR and HLA-B homozygosity was associated with significantly increased risk of graft failure. In addition to the number of HLA mismatch between KTRs and donors, the donor allele state should be considered to predict transplant outcomes.

Predictive factors for tuberculosis in patients with a TB-PCR-negative bronchial aspirate.

PURPOSE: Pulmonary tuberculosis (PTB), with a tuberculosis (TB)-polymerase chain reaction (PCR)-negative bronchial aspirate (BA), but a positive culture result is often encountered in clinical practice. However, limited data are available concerning clinical judgment in patients with suspected PTB and a TB-PCR-negative BA pending culture results. The present study aimed to identify predictors for PTB in patients with a TB-PCR-negative BA. METHODS: A retrospective study was conducted on patients who had undergone a bronchoscopy because of suspected PTB. Clinical, laboratory, and computed tomography (CT) findings were investigated in PTB patients with TB-PCR-negative but positive culture BA results, and non-PTB patients with a radiographic lesion comparable to the former. RESULTS: Of 250 patients screened, 31 (12 %) were diagnosed with PTB by positive culture results only. Of these 31 patients, 30 (97 %) had a lesion within one-third of the hemithorax as determined by chest radiography. In the final analysis of 30 PTB and 65 non-PTB patients with comparable radiographic lesions, a positive QuantiFERON-TB Gold In-Tube (QFT) result was independently associated with an increased risk of a positive TB culture. CT findings of consolidation were a negative predictor for PTB. Patients with a negative QFT result and consolidation had a negative predictive value of 95 % for PTB, while patients with a positive QFT result and nodular CT abnormalities without consolidation had a positive predictive value of 86 % for PTB. CONCLUSION: The simple combination of CT findings of consolidation and QFT test results may help clinicians to refine decision-making in patients with a TB-PCR-negative BA.

Living donor liver transplantation for acute hepatic failure caused by reactivation of hepatitis B virus infection after chemotherapy for hematologic malignancy: case reports.

Cancer chemotherapy in chronic hepatitis B virus (HBV) carriers occasionally leads to acute hepatic failure (AHF) from viral reactivation resulting in an high mortality rate. In this situation, living donor liver transplantation (LDLT) can be life saving. Herein we have reported 2 cases of successful LDLT performed for AHF caused by reactivation of HBV infection during chemotherapy for hematologic malignancies. In case 1, a 38-year-old male HBV carrier with a neck mass was hisopathologically diagnosed as Hodgkin's lymphoma. During 4 cycles of chemotherapy he developed right upper quadrant pain and jaundice. Laboratory data (alanine amino transferase, 701 U/L, total bilirubin: 7.92 mg/dL, positive hepatitis B e antigen showed that he had experienced an acute exacerbation of chronic hepatitis. Soon, he developed grade IV hepatic encephalopathy with a total bilirubin level of 50.56 mg/dL and a model for End-Stage Liver Disease score of 40. After LDLT, he has been free of relapse for 52 months so far. In case 2, a 49-year-old male HBV carrier was diagnosed in the chronic phase of chronic myeloid leukemia. The patient had been under Imatinib treatment for 1 year until he was admitted for AHF. He developed grade II encephalopathy with a total bilirubin of 50.8 mg/dL. We performed LDLT; the patient has been free of relapse for 17 months. LDLT was a life-saving procedure for AHF caused by reactivation of HBV during chemotherapy for hematologic malignancy. It can provide long-term survival if the coexistent hematologic malignancy has been controlled.

HLA Class II-specific antibodies can react with T cells in flow cytometry crossmatch: a case report.

HLA Class I-specific antibodies are usually detected using a flow cytometry HLA crossmatch using T cells. A positive case is shown as a single, right-shifted peak on the anti-IgG FITC histogram of T cells. We report a case showing 2 peaks occurring concurrently, both positive and negative. The positive peak resulted from the binding of HLA Class II-specific antibodies to donor-activated T cells expressing the HLA-DR antigens. This case suggested donor-specific HLA Class II-specific antibodies can bind to some T cells as well as to whole B cells.

Rapid helper T-cell recovery above 200 x 10 6/l at 3 months correlates to successful transplant outcomes after allogeneic stem cell transplantation.

The current study evaluates the role of quantitative measurement of peripheral lymphocyte subsets, especially CD4+ helper T-cell recovery, in predicting transplant outcomes including overall survival (OS) and non-relapse mortality (NRM) after allogeneic stem cell transplantation. A total of 69 allogeneic recipients were included with following diagnoses: acute myeloid leukemia 42, acute lymphoblastic leukemia 5, chronic myeloid leukemia 15, non-Hodgkin's lymphoma 5 and high-risk myelodysplastic syndrome 2. The peripheral lymphocyte subset counts (CD3+ T cells, CD3+4+ helper T cells, CD3+8+ cytotoxic T cells, CD19+ B cells, and CD56+ natural killer cells) were measured at 3, 6 and 12 months. The CD4+ helper T-cell reconstitution at 3 months was strongly correlated with OS (P<0.0001), NRM (P=0.0007), and opportunistic infections (P=0.0108) at the cutoff value of 200 x 10(6)/l CD4(+) helper T cells. Rapid CD4+ helper T-cell recovery was also associated with a higher CD4+ helper T-cell transplant dose (P=0.006) and donor type (P<0.001). An early CD4+ helper T-cell recovery at 3 months correlated with a subsequent faster helper T-cell recovery until 12 months, yet not with B-cell recovery. In a multivariate analysis, rapid recovery of CD4+ helper T cells at 3 months was a favorable prognostic factor together with higher CD34+ cell transplant dose in terms of OS (P=0.001) and NRM (P=0.005).

Comparison of the reverse transcription-PCR with the branched DNA assay for measurement of human immunodeficiency virus type 1 RNA levels in plasma of Korean patients.

Viral load testing of human immunodeficiency virus (HIV) is an essential tool for initiating and monitoring the antiretroviral therapy for HIV patients. To this end, several methods including polymerase chain reaction (PCR), branched DNA (bDNA), nucleic acid sequence based amplification assay (NASBA) and internally controlled virion PCR (ICV PCR) have become available. Of these methods, the standard reverse transcription-PCR (RT-PCR) assay has been widely used in Korea. However, no comparison study has been performed among the various detection methods currently used in Korean patients. We evaluated the correlation and agreement between the PCR and the branched DNA (bDNA) assay for measurement of HIV RNA in Korean patients. Eighty randomly selected samples from HIV-1-seropositive patients visiting Yonsei Medical Center Severance Hospital were studied. We found that these assays show good agreement, have a reliable correlation (r = 0.92, mean difference in log10 copies/ mL +/- 2 standard deviation = 0.098 +/- 0.805) and produce values whose relationship is given by the following equation: log10v3 bDNA = -0.3405 + 1.0601 x log10RT-PCR. Thus, we conclude that these two methods may allow direct comparison of the results obtained from different assay systems.

A case of nephrotic syndrome associated with protein S deficiency and cerebral thrombosis.

Protein S is found in two forms in plasma; as free and functionally active protein S, and complexed to C4b-binding protein. Patients with nephrotic syndrome are at risk for arterial and venous thrombosis at various localizations, and acquired protein S deficiency due to the selective urinary loss of the free form may be a risk factor for the development of thromboembolic complications. We report a case of cerebral arterial thrombosis associated with decreased level of free protein S antigen (44%) in a 39-year-old female patient with nephrotic syndrome.