Bovine Neonatal Pancytopenia is a heritable trait of the dam rather than the calf and correlates with the magnitude of vaccine induced maternal alloantibodies not the MHC haplotype.

Bovine Neonatal Pancytopenia (BNP), a bleeding syndrome of neonatal calves, is caused by alloantibodies absorbed from the colostrum of particular cows. A commercial BVD vaccine is the likely source of alloantigens eliciting BNP associated alloantibodies. We hypothesized that the rare occurrence of BNP in calves born to vaccinated dams could be associated with genetic differences within dams and calves. We found that the development of BNP within calves was a heritable trait for dams, not for calves and had a high heritability of 19%. To elucidate which genes play a role in the development of BNP we sequenced candidate genes and characterized BNP alloantibodies. Alloantigens present in the vaccine have to be presented to the dam's immune system via MHC class II, however sequencing of DRB3 showed no differences in MHC class II haplotype between BNP and non-BNP dams. MHC class I, a highly polymorphic alloantigen, is an important target of BNP alloantibodies. Using a novel sequence based MHC class I typing method, we found no association of BNP with MHC class I haplotype distribution in dams or calves. Alloantibodies were detected in both vaccinated BNP and non-BNP dams and we found no differences in alloantibody characteristics between these groups, but alloantibody levels were significantly higher in BNP dams. We concluded that the development of BNP in calves is a heritable trait of the dam rather than the calf and genetic differences between BNP and non-BNP dams are likely due to genes controlling the quantitative alloantibody response following vaccination.

The Induction of IgM and IgG Antibodies against HLA or MICA after Lung Transplantation.

The production of IgG HLA antibodies after lung transplantation (LTx) is considered to be a major risk factor for the development of chronic rejection, represented by the bronchiolitis obliterans syndrome (BOS). It has recently been observed that elevated levels of IgM HLA antibodies also correlates with the development of chronic rejection in heart and kidney transplantation. This study investigates the relationship between IgM and IgG antibodies against HLA and MICA after lung transplantation. Serum was collected from 49 patients once prior to transplantation and monthly for up to 1 year after lung transplantation was analyzed by Luminex to detect IgM and IgG antibodies against HLA and MICA. The presence of either IgM or IgG HLA and/or MICA antibodies prior to or after transplantation was not related to survival, gender, primary disease, or the development of BOS. Additionally, the production of IgG alloantibodies was not preceded by an increase in levels of IgM, and IgM levels were not followed by an increase in IgG. Under current immune suppressive regimen, although the presence of IgM antibodies does not correlate with BOS after LTx, IgM( high) IgG( low) HLA class I antibody titers were observed more in patients with BOS compared to patients without BOS.

Soluble CD30 measured after lung transplantation does not predict bronchiolitis obliterans syndrome in a tacrolimus/mycophenolate mofetil-based immunosuppressive regimen.

BACKGROUND: The purpose of this study was to determine the utility of post-transplant serum soluble CD30 levels as a biomarker for the development of the bronchiolitis obliterans syndrome (BOS) after lung transplantation during a tacrolimus/mycophenolate mofetil-based regimen. METHODS: Soluble CD30 (sCD30) concentrations were measured prior to transplantation and in 175 samples taken after transplantation in 7 patients developing BOS and 7 non-BOS patients closely matched for age, underlying diseases, follow-up and gender. RESULTS: High pre-transplant sCD30 levels dropped significantly after lung transplantation, but in the post-transplant samples no differences could be detected between patients developing BOS or not, and no changes were found prior to or during the development of BOS. CONCLUSIONS: After transplantation, sCD30 levels are consistently suppressed, but BOS is not prevented, indicating that sCD30 cannot be used as a biomarker to predict BOS after transplantation in the regimen employed.

The killer immunoglobulin-like receptor (KIR) group A haplotype is associated with bronchiolitis obliterans syndrome after lung transplantation.

BACKGROUND: The development of bronchiolitis obliterans syndrome (BOS) after lung transplantation is associated with viral infections. Natural killer (NK) cells are involved in the lysis of viral infected cells, and their activation is largely controlled by activating and inhibitory killer immunoglobulin-like receptors (KIRs). We hypothesized that KIR ligand incompatibility and recipients' individual KIRs could influence the development of BOS and the incidence of cytomegalovirus reactivation after lung transplantation. METHODS: The KIR gene contents were determined in 48 patients who received a lung transplant, and human leukocyte antigen (HLA)-Cw and HLA-Bw4 typing was performed on their respective donors. RESULTS: BOS developed in 7 patients and cytomegalovirus reactivation occurred in 16. BOS developed in 5 of 19 patients homozygous for KIR haplotype A compared with 2 of 27 patients with KIR haplotype AB and B (homozygous; p = 0.03; log-rank test). In none of the patients with BOS was the activating KIR2DS5 gene detected, whereas it was present in 35% of patients without BOS (p = 0.04; log-rank test). No correlation was found between KIR gene content and cytomegalovirus reactivation. CONCLUSION: Our results suggest that the lack of activating KIRs may play an important role in the development of BOS but not in the control of cytomegalovirus reactivation after lung transplantation.

Pre-transplant soluble CD30 is associated with bronchiolitis obliterans syndrome after lung transplantation.

BACKGROUND: The purpose of this study was to determine the clinical relevance of soluble CD30 (sCD30) concentrations in sera from lung transplantation (LTx) candidates. METHODS: Soluble CD30 concentrations were determined by enzyme-linked immunoassay in pre-transplantation sera of 38 LTx candidates and in serial samples taken after LTx from 10 patients. RESULTS: LTx candidates did not have increased serum sCD30 concentrations when compared with healthy controls (mean +/- SE: 22.3 +/- 2.7 vs 26.2 +/- 3.4 U/ml). No relation could be found between age and serum sCD30 concentrations, neither in the pre-transplant patients nor in the healthy controls. In addition, no differences in sCD30 values could be detected between patients sorted by their original type of lung disease. Measurement of sCD30 in pre-transplant sera of LTx patients showed that the median concentration was 20 U/ml and that LTx patients with low sCD30 (< or = 20 U/ml) had a statistically significant (p = 0.039) longer period of freedom from bronchiolitis obliterans syndrome (BOS) compared to those with a high sCD30 concentration (> 20 U/ml). Furthermore, sCD30 concentrations in sera taken at several timepoints after LTx remained stable, although a peak could be observed before the clinical manifestation of acute rejection (AR). CONCLUSIONS: Soluble CD30 before lung transplantation is significantly associated with an increased risk of BOS after transplantation.

Identification of non-HLA target antigens recognized after lung transplantation.

BACKGROUND: It has become evident that, besides cellular allogeneic immune responses against airway epithelial cells (AEC), humoral responses also contribute significantly to the pathogenesis of bronchiolitis obliterans syndrome (BOS) after lung transplantation (LTx). Antibody responses against transplanted lungs are directed against HLA and non-HLA antigens, but the identity of the latter antigens is presently unknown. METHODS: The main purpose of this study is to identify non-HLA target antigens on donor lungs recognized by patients' antibodies after LTx. Serum samples were taken before and 6 months after lung transplantation from 11 patients (4 men and 6 women, median age 44 years, range 18 to 63 years). Protein expression libraries were made from the luminal side containing AEC of discarded the donor bronchus, which was snap frozen in liquid N(2) during the organ harvesting procedure. Subsequently, all sera were analyzed for reactivity against library-encoded antigens by serologic analysis of recombinant cDNA expression libraries (SEREX). Recognized gene products were sequenced and analyzed by the NCBI/BLAST server. RESULTS: From a total of +/-3 x 10(4) gene products analyzed, six different non-HLA antigens were recognized by individual patient sera. Gene analysis indicated that they consisted of both polymorphic (PSMC4, F3, LOC284058, PLUNC, ZNF33A) and non-polymorphic (XP_931864) antigens. Cross-sectional analysis indicated that some antigens were recognized by 4 of 10 patient sera tested. CONCLUSIONS: Antibodies directed against non-HLA antigens are present after LTx, and can be identified using the SEREX technique. Identification of target antigens recognized after LTx will improve our understanding of the pathogenesis of BOS. Monitoring of the antibody response may be used to predict BOS.