Monitoring of Serological, Cellular and Genomic Biomarkers in Transplantation, Computational Prediction Models and Role of Cell-Free DNA in Transplant Outcome.

The process and evolution of an organ transplant procedure has evolved in terms of the prevention of immunological rejection with the improvement in the determination of immune response genes. These techniques include considering more important genes, more polymorphism detection, more refinement of the response motifs, as well as the analysis of epitopes and eplets, its capacity to fix complement, the PIRCHE algorithm and post-transplant monitoring with promising new biomarkers that surpass the classic serum markers such as creatine and other similar parameters of renal function. Among these new biomarkers, we analyze new serological, urine, cellular, genomic and transcriptomic biomarkers and computational prediction, with particular attention to the analysis of donor free circulating DNA as an optimal marker of kidney damage.

Early Cytomegalovirus Reactivation in Renal Recipients Is Associated with High Levels of B Cell Maturation Antigen Transcript Expression Prior to Transplantation.

Cytomegalovirus (CMV) infection is the most frequent infection episode in kidney transplant (KT) recipients. Reactivation usually occurs in the first three months after transplantation and is associated with higher cellular and/or antibody-mediated rejection rates and poorer graft performance. CMV induces the expression of BAFF (B-cell-activating factor, a cytokine involved in the homeostasis of B cells), which communicates signals for survival and growth to B cells and virus-specific plasma cells via the R-BAFF (BAFF receptor), TACI (the calcium modulator, the cyclophilin ligand interactor), and BCMA (B cell maturation antigen) receptors. These molecules of the BAFF system have also been suggested as biomarkers for the development of alloantibodies and graft dysfunction. This prospective study included 30 CMV-IgG seropositive KT recipients. The expression levels of the genes BAFF-R, transmembrane activator and CAML interactor (TACI), and B cell maturation antigen (BCMA) in peripheral blood leukocytes (PBL) pre-KT were determined using qPCR. qPCR was also used to monitor CMV reactivation in the first three months following KT. The remainder of the KT recipients were classified as CMV- reactivation, and those with more than 500 copies/mL in at least one sample were classified as CMV+ reactivation. There were no discernible variations in the BAFF-R and TACI transcript expression levels. In the CMV+ group, we examined the relationship between the transcript levels and peak viremia. Peak viremia levels and BCMA transcript levels showed a strong correlation. BAFF-R and TACI expressions showed no measurable differences. In patients with early CMV reactivation, high BCMA receptor expression was associated with increased plasmablast, lymphocyte B cell class-switched levels (LBCS), and viral load. Our findings demonstrate that pre-KT BCMA transcript levels increased in KT recipients with early CMV reactivation. These transcript levels positively correlate with peak viremia and weakly with plasmablast and LBCS levels in PBLs.

Immune transcriptome analysis in predatory beetles reveals two cecropin genes overexpressed in mandibles.

The great complexity and variety of the innate immune system and the production of antimicrobial peptides in insects is correlated with their evolutionary success and adaptation to different environments. Tiger beetles are an example of non-pest species with a cosmopolitan distribution, but the immune system is barely known and its study could provide useful information about the humoral immunity of predatory insects. Suppression subtractive hybridization (SSH) was performed in Calomera littoralis beetles to obtain a screening of those genes that were overexpressed after an injection with Escherichia coli lipopolysaccharide (LPS). Several genes were identified to be related to immune defense. Among those genes, two members of the cecropin antimicrobial peptides were characterized and identified as CliCec-A and CliCec-B2. Both protein sequences showed cecropin characteristics including 37 and 38 residue mature peptides, composed by two α-helices structures with amphipathic and hydrophobic nature, as shown in their predicted three-dimensional structure. Chemically synthesized CliCec-B2 confirmed cecropin antimicrobial activity against some Gram (+) and Gram (-) bacteria, but not against yeast. Expression of both cecropin genes was assessed by qPCR and showed increases after a LPS injection and highlighted their overexpression in adult beetle mandibles, which could be related to their alimentary habits.

Effects of lipopolysaccharide and juvenile hormone III treatments on cell growth and gene expression in the Ceratitis capitata (Diptera: Tephritidae) CCE/CC128 cell line.

The Mediterranean fruit fly Ceratitis capitata is one of the most important insect pest species in the world. It has a high colonization capacity and population variety, giving it considerable genetic diversity. Strategies for its control have included the sterile insect technique and insect growth regulators. Many studies have analyzed the medfly transcriptome, and along with the medfly genome sequence, the sequences of multiple genes related to sex determination, mating, development, pheromone detection, immunity, or stress have been identified. In this study, the medfly CCE/CC128 cell line was used to assess cell growth variation and changes in the expression of genes covering different functions, after lipopolysaccharide (LPS) and juvenile hormone III (JHIII) treatments. No significant effects on cell growth and gene expression were observed in the cells treated with LPS. In the cells treated with JHIII, the results showed significant effects on cell growth, and an overexpression was found of the Shade gene, one of the Halloween gene members of the cytochrome p450 family, which is involved in development and the synthesis of 20-hydroxyecdysone. This study shows preliminary results on the insect cell line in combination with whole-genome sequencing, which can facilitate studies regarding growth, toxicity, immunity, and transcriptome regulations as a response to different compounds and environmental alterations.

New Entamoeba group in howler monkeys (Alouatta spp.) associated with parasites of reptiles.

Our knowledge of the parasite species present in wildlife hosts is incomplete. Protozoans such as amoebae of the genus Entamoeba infect a large variety of vertebrate species, including NHPs. However, traditionally, their identification has been accomplished through microscopic evaluation; therefore, amoeba species have not always been identified correctly. We searched for Entamoeba spp. using a fragment of the small subunit rDNA in free-ranging howler monkeys (Alouatta palliata and A. pigra) from southeast Mexico. One hundred fifty five samples were collected, with 46 from A. palliata and 109 from A. pigra and 8 of the total samples were positive. We detected a new clade of Entamoeba, which was separated from other described species but closer to E. insolita, as well as an unnamed sequence typically found in iguana species with low shared identity values (<90%). We designated this new clade as conditional lineage 8 (CL8) and we have shown that members of this group are not exclusive to reptiles.

Islands in the desert: Species delimitation and evolutionary history of Pseudotetracha tiger beetles (Coleoptera: Cicindelidae: Megacephalini) from Australian salt lakes.

The Australian salt lakes are a natural archipelago-like laboratory for investigating evolutionary and population processes. Their environmental conditions have not undergone relevant changes since the aridification of Australia 10-5 million years ago. The genus Pseudotetracha, a group of nocturnal tiger beetles found on these remote salt lakes, includes 20 described species. Recent studies based on molecular markers and cytogenetics hinted at the existence of cryptic species within this group. Here we use various species delimitation algorithms to detect a high number of cryptic and undescribed taxa, and challenge the validity of the taxonomic characters traditionally used for discerning species in this group. Our analyses show that the divergence dates of the clades, between 10 and 5 million years ago, correspond to the period in which Australia was undergoing an aridification process that probably isolated the ancestral Pseudotetracha populations to individual lakes or palaeodrainage basins. This implies an important role of the isolation, produced by the aridification of Australia, in the speciation and divergence of Pseudotetracha, which underwent a remarkable radiation as the populations became geographically restricted.

Identification and Characterization of Pathogen-Response Genes (repat) in Spodoptera frugiperda (Lepidoptera: Noctuidae).

The fall armyworm (Spodoptera frugiperda, Noctuidae, Lepidoptera) is one of the most important crop pests in the Americas, causing significant damage to maize, rice and sorghum. The mechanisms that determine its defences against pathogens are particularly relevant for the development of management and control strategies. We used an in silico approach to identify and characterize pathogen response genes (repat) present in different tissue libraries of S. fugiperda. The analyses revealed complete cDNA for nine repat genes; of these, repat15 and repat39 were found in libraries from a specific tissue--the midgut of larvae fed with xenobiotic substances. High expression levels of some genes were found in different libraries: 39 hits in repat30 in challenged hemocytes, 16 hits in repat31 in fat body, 10 hits in repat32 in fat body and 10 in challenged hemocytes, and 10 hits in repat38 in midgut of non-treated larvae and midgut of larvae fed with natural and xenobiotic substances. The genes corresponded to two ontology categories, stress response and immune response, and their phylogenetic relationships, nucleotide similarity, number of amino acid residues and molecular weights agree with what has been described for repat genes. It is noteworthy that proteins encoded by the repat genes of S. frugiperda have important defence functions in other tissues beyond midgut and that their functional categories are likely diverse, as they are related to cell envelope structure, energy metabolism, transport and binding.

Identification and characterisation of putative seminal fluid proteins from male reproductive tissue EST libraries in tiger beetles.

BACKGROUND: The study of proteins transferred through semen can provide important information for biological questions such as adaptive evolution, the origin of new species and species richness. The objective of this study was to identify seminal fluid proteins (SFPs) that may contribute to the study of the reproductive system of tiger beetles (cicindelids), a group of more than 2,500 species distributed worldwide that occupy a great diversity of habitats. RESULTS: Two cDNA libraries were constructed from the male gonads of Calomera littoralis and Cephalota litorea. Expressed sequence tags (ESTs) were analysed by bioinformatics approaches and 14 unigenes were selected as candidate SFPs, which were submitted to Reverse Transcription Polymerase Chain Reaction (RT-PCR) to identify patterns of tissue-specific expression. We have identified four novel putative SFPs of cicindelids, of which similarity searches did not show homologues with known function. However, two of the protein classes (immune response and hormone) predicted by Protfun are similar to SFPs reported in other insects. Searches for homology in other cicindelids showed one lineage specific SFPs (rapidly evolving proteins), only present in the closely related species C. littoralis and Lophyra flexuosa and two conserved SFP present in other tiger beetles species tested. CONCLUSIONS: This work represents the first characterisation of putative SFPs in Adephagan species of the order Coleoptera. The results will serve as a foundation for further studies aimed to understand gene (and protein) functions and their evolutionary implications in this group of ecologically relevant beetles.

Partial sequence homogenization in the 5S multigene families may generate sequence chimeras and spurious results in phylogenetic reconstructions.

Multigene families have provided opportunities for evolutionary biologists to assess molecular evolution processes and phylogenetic reconstructions at deep and shallow systematic levels. However, the use of these markers is not free of technical and analytical challenges. Many evolutionary studies that used the nuclear 5S rDNA gene family rarely used contiguous 5S coding sequences due to the routine use of head-to-tail polymerase chain reaction primers that are anchored to the coding region. Moreover, the 5S coding sequences have been concatenated with independent, adjacent gene units in many studies, creating simulated chimeric genes as the raw data for evolutionary analysis. This practice is based on the tacitly assumed, but rarely tested, hypothesis that strict intra-locus concerted evolution processes are operating in 5S rDNA genes, without any empirical evidence as to whether it holds for the recovered data. The potential pitfalls of analysing the patterns of molecular evolution and reconstructing phylogenies based on these chimeric genes have not been assessed to date. Here, we compared the sequence integrity and phylogenetic behavior of entire versus concatenated 5S coding regions from a real data set obtained from closely related plant species (Medicago, Fabaceae). Our results suggest that within arrays sequence homogenization is partially operating in the 5S coding region, which is traditionally assumed to be highly conserved. Consequently, concatenating 5S genes increases haplotype diversity, generating novel chimeric genotypes that most likely do not exist within the genome. In addition, the patterns of gene evolution are distorted, leading to incorrect haplotype relationships in some evolutionary reconstructions.

Incomplete sequence homogenization in 45S rDNA multigene families: intermixed IGS heterogeneity within the single NOR locus of the polyploid species Medicago arborea (Fabaceae).

BACKGROUND AND AIMS: Ribosomal sequences have become the classical example of the genomic homogenization of nuclear multigene families. Despite theoretical advantages and modelling predictions that support concerted evolution of the 45S rDNA, several reports have found intragenomic polymorphisms. However, the origins and causes of these rDNA polymorphisms are difficult to assess because seed plants show a wide range of 45S rDNA loci number variation, especially in polyploids. Medicago arborea is a tetraploid species that has a single 45S rDNA locus. This feature makes this species a suitable case study to assess the fate of ribosomal IGS homogenization in polyploid species showing nucleolus organizer region (NOR) reduction. METHODS: The intergenic spacer (IGS) region was amplified by long PCR and the fragments were cloned and sequenced by a primer-walking strategy. The physical mapping of the whole and partial IGS variants was assessed by fluorescent in situ hybridization (FISH) and fibre-FISH methods on mitotic chromosomes and extended DNA fibres, respectively. KEY RESULTS: Two IGS fragments of 4·8 and 3·5 kb were obtained showing structural features of functional sequences. The shorter variant appears to be a truncated copy of the 4·8 kb fragment that lacks the duplication of the transcription initiation site region and the entire D region. The physical localization of the two IGS variants on metaphase chromosomes and extended DNA fibres using FISH corroborated their joint presence within the same locus. In addition, no spatial structure of the two variants was detected within the NOR. CONCLUSIONS: The results suggest that full sequence homogenization is not operating within the NOR locus of M. arborea. The structure of the NOR locus reported here departs from the models of IGS heterogeneity present in plants and caution against assuming the widespread belief that intragenomic ribosomal heterogeneity is mainly due to sequence variation between paralogous loci.

Measurable residual disease study through three different methods can anticipate relapse and guide early interventions in childhood acute lymphoblastic leukemia.

INTRODUCTION: Acute lymphoblastic leukemia (ALL) is the most common cancer among children. Measurable residual disease (MRD, previously named minimal residual disease) study can guide therapy adjustments or preemptive interventions that might avoid hematological relapse. METHODS: Clinical decision making and patient outcome were evaluated in 80 real-life childhood ALL patients, according to the results observed in 544 bone marrow samples analyzed with three MRD methods: multiparametric flow cytometry (MFC), fluorescent in-situ hybridization (FISH) on B or T-purified lymphocytes and patient-specific nested reverse transcription polymerase chain reaction (RT-PCR). RESULTS: Estimated 5 year overall survival and event-free survival were 94% and 84.1%, respectively. A total of 12 relapses in 7 patients were associated with positive MRD detection with at least one of the three methods: MFC (p < 0.00001), FISH (p < 0.00001) and RT-PCR (p = 0.013). MRD assessment allowed the anticipation of relapse and adapted early interventions with different approaches including chemotherapy intensification, blinatumomab, HSCT and targeted therapy to halt relapse in five patients, although two of them relapsed afterwards. CONCLUSION: MFC, FISH and RT-PCR are complementary methods for MRD monitoring in pediatric ALL. Although, our data clearly show that MDR positive detection is associated with relapse, continuation of standard treatment, intensification or other early interventions were able to halt relapse in patients with different risks and genetic background. More sensitive and specific methods are warranted to enhance this approach. However, whether early treatment of MRD can improve overall survival in patients with childhood ALL needs to be evaluated in adequately controlled clinical trials.

MicroRNAs as Potential Graft Rejection or Tolerance Biomarkers and Their Dilemma in Clinical Routines Behaving like Devilish, Angelic, or Frightening Elements.

Allograft rejection is a widespread complication in allograft recipients with chronic kidney disease. Undertreatment of subclinical and clinical rejection and later post-transplant problems are caused by an imperfect understanding of the mechanisms at play and a lack of adequate diagnostic tools. Many different biomarkers have been analyzed and proposed to detect and monitor these crucial events in transplant outcomes. In this sense, microRNAs may help diagnose rejection or tolerance and indicate appropriate treatment, especially in patients with chronic allograft rejection. As key epigenetic regulators of physiological homeostasis, microRNAs have therapeutic potential and may indicate allograft tolerance or rejection. However, more evidence and clinical validation are indispensable before microRNAs are ready for clinical prime time.

Genotypic Frequencies of Mutations Associated with Alpha-1 Antitrypsin Deficiency in Unrelated Bone Marrow Donors from the Murcia Region Donor Registry in the Southeast of Spain.

Alpha-1 antitrypsin (AAT1) deficiency (AAT1D) is an inherited disease with an increased risk of chronic obstructive pulmonary disease (COPD), liver disease, and skin and blood vessel problems. AAT1D is caused by mutations in the SERPINE1 gene (Serine Protease Inhibitor, group A, member 1). Numerous variants of this gene, the Pi system, have been identified. The most frequent allelic variants are Pi*M, Pi*S, and Pi*Z. The development of COPD requires both a genetic predisposition and the contribution of an environmental factor, smoking being the most important. Studies on this deficiency worldwide are very scarce, and it is currently considered a rare disease because it is underdiagnosed. The aim of this study was to analyze the genotypic frequencies of mutations associated with AAT1 deficiency in unrelated bone marrow donors from the donor registry of the Region of Murcia in southeastern Spain due to the high risk of presenting with different pathologies and underdiagnosis in the population. A total of 112 DNA-healthy voluntary unrelated bone marrow donors from different parts of the Region of Murcia were analyzed retrospectively. AAT1 deficiency patient testing involved an automated biochemical screening routine. The three main variants, Pi*M, Pi*Z, and Pi*S, were analyzed in the SERPINE1 gene. Our results showed a frequency of 3.12% of the Pi*Z (K342) mutation in over 224 alleles tested in the healthy population. The frequency of Pi*S (V264) was 11.1%. The frequency of the haplotype with the most dangerous mutation, EK342 EE264, was 4.46%, and the frequency of EK342 EV264 was 1.78% in the healthy population. Frequencies of other EE342 EV264-mutated haplotypes accounted for 18.7%. As for the EE342 VV264 haplotype, 0.89% of the total healthy population presented heterozygous for the EV264 mutation and one individual presented homozygous for the VV264 mutation. In conclusion, the frequencies of Pi mutations in the healthy population of the Region of Murcia were not remarkably different from the few studies reported in Spain. The genotype and haplotype frequencies followed the usual pattern. Health authorities should be aware of this high prevalence of the Pi*S allelic variant and pathological genotypes such as Pi*MZ and Pi*SZ in the healthy population if they consider screening the smoking population.

Clinical Significance of the Pre-Transplant CXCR3 and CCR6 Expression on T Cells In Kidney Graft Recipients.

BACKGROUND: T cells play a fundamental role in the processes that mediate graft rejection, tolerance, and defense against infections. The CXCR3 and CCR6 receptors, highly expressed in Th1 (type 1 T helper cells)/Tc1 (T cytotoxic cells, type 1), Th1-Tc1, and Th17-Tc17 lymphocytes, respectively, participate in cell migration toward inflamed tissues. The altered expression level of CXCR3 and CCR6 has been associated with different clinical events after renal transplantation, such as acute rejection (AR) and chronic graft dysfunction, but data are still limited. In this study, we evaluated the expression of the receptor CXCR3 and CCR6 in peripheral blood T lymphocytes from kidney transplant recipients (KTR) and their association with viral infections, AR, and allograft function. METHODS: Through flow cytometry, the peripheral blood expression of CXCR3 and CCR6 in T cells was evaluated in a pretransplant collection of KTR. The levels of these T subpopulations and their association with the incidence of AR, kidney graft function, viral infections, cytomegalovirus, and BK virus were studied. Adverse clinical events and graft function were monitored during the first year post transplant. RESULTS: KTRs with low pretransplantation levels of Th17 (CD4+CXCR3-CCR6+) (tertile 1, Th17<16.4%) had a higher risk of suffering AR during the first year post transplantation (P = .033). KTRs with viral infections or reactivations during the first 3 months post transplantation had significantly lower levels of Tc17 (CD8+CXCR3-CCR6+) and higher levels of Th1 (CD4+CXCR3+CCR6-). In patients with cytomegalovirus reactivations, the viral peak correlates negatively with the pretransplant levels of Th1 (r = -0.606, P = .037). CONCLUSIONS: Pretransplantation assessment of Th1-Th17 and Tc1-Tc17 levels may help predict post-transplant clinical events such as AR and reactivation of viral infections.

All That Glitters in cfDNA Analysis Is Not Gold or Its Utility Is Completely Established Due to Graft Damage: A Critical Review in the Field of Transplantation.

In kidney transplantation, a biopsy is currently the gold standard for monitoring the transplanted organ. However, this is far from an ideal screening method given its invasive nature and the discomfort it can cause the patient. Large-scale studies in renal transplantation show that approximately 1% of biopsies generate major complications, with a risk of macroscopic hematuria greater than 3.5%. It would not be until 2011 that a method to detect donor-derived cell-free DNA (dd-cfDNA) employing digital PCR was devised based on analyzing the differences in SNPs between the donor and recipient. In addition, since the initial validation studies were carried out at the specific moments in which rejection was suspected, there is still not a good understanding of how dd-cfDNA levels naturally evolve post-transplant. In addition, various factors, both in the recipient and the donor, can influence dd-cfDNA levels and cause increases in the levels of dd-cfDNA themselves without suspicion of rejection. All that glitters in this technology is not gold; therefore, in this article, we discuss the current state of clinical studies, the benefits, and disadvantages.

Measurable residual disease study through three different methods can anticipate relapse and guide pre-emptive therapy in childhood acute myeloid leukemia.

PURPOSE: Although outcomes of children with acute myeloid leukemia (AML) have improved over the last decades, around one-third of patients relapse. Measurable (or minimal) residual disease (MRD) monitoring may guide therapy adjustments or pre-emptive treatments before overt hematological relapse. METHODS: In this study, we review 297 bone marrow samples from 20 real-life pediatric AML patients using three MRD monitoring methods: multiparametric flow cytometry (MFC), fluorescent in situ hybridization (FISH) and polymerase chain reaction (PCR). RESULTS: Patients showed a 3-year overall survival of 73% and a 3-year event-free survival of 68%. Global relapse rate was of 25%. All relapses were preceded by the reappearance of MRD detection by: (1) MFC (p = 0.001), (2) PCR and/or FISH in patients with an identifiable chromosomal translocation (p = 0.03) and/or (3) one log increase of Wilms tumor gene 1 (WT1) expression in two consecutive samples (p = 0.02). The median times from MRD detection to relapse were 26, 111, and 140 days for MFC, specific PCR and FISH, and a one log increment of WT1, respectively. CONCLUSIONS: MFC, FISH and PCR are complementary methods that can anticipate relapse of childhood AML by weeks to several months. However, in our series, pre-emptive therapies were not able to prevent disease progression. Therefore, more sensitive MRD monitoring methods that further anticipate relapse and more effective pre-emptive therapies are needed.

Amplification, contraction and genomic spread of a satellite DNA family (E180) in Medicago (Fabaceae) and allied genera.

BACKGROUND AND AIMS: Satellite DNA is a genomic component present in virtually all eukaryotic organisms. The turnover of highly repetitive satellite DNA is an important element in genome organization and evolution in plants. Here we assess the presence and physical distribution of the repetitive DNA E180 family in Medicago and allied genera. Our goals were to gain insight into the karyotype evolution of Medicago using satellite DNA markers, and to evaluate the taxonomic and phylogenetic signal of a satellite DNA family in a genus hypothesized to have a complex evolutionary history. METHODS: Seventy accessions from Medicago, Trigonella, Melilotus and Trifolium were analysed by PCR to assess the presence of the repetitive E180 family, and fluorescence in situ hybridization (FISH) was used for physical mapping in somatic chromosomes. KEY RESULTS: The E180 repeat unit was PCR-amplified in 37 of 40 taxa in Medicago, eight of 12 species of Trigonella, six of seven species of Melilotus and in two of 11 Trifolium species. Examination of the mitotic chromosomes revealed that only 13 Medicago and two Trigonella species showed FISH signals using the E180 probe. Stronger hybridization signals were observed in subtelomeric and interstitial loci than in the pericentromeric loci, suggesting this satellite family has a preferential genomic location. Not all 13 Medicago species that showed FISH localization of the E180 repeat were phylogenetically related. However, nine of these species belong to the phylogenetically derived clade including the M. sativa and M. arborea complexes. CONCLUSIONS: The use of the E180 family as a phylogenetic marker in Medicago should be viewed with caution. Its amplification appears to have been produced through recurrent and independent evolutionary episodes in both annual and perennial Medicago species as well as in basal and derived clades.

Evaluating the Link between BAFF System Gene Expression and Acute Rejection Development in Kidney Transplantation.

B-cell activating factor (BAFF) system signaling is critical for B-cell homeostasis, effector functions, and tolerance maintenance in transplants, but it has not been studied in kidney transplant recipients (KTRs). The aim was to analyze the changes in BAFF system expression in KTRs with/without acute rejection (AR/NAR). The BAFF system expression was analyzed by qPCR in 40 KTRs. A meta-analysis of BAFF system expression and histological renal damage was identified by the Chronic Allograft Damage Index (CADI) and performed from the GEO database. Proliferation-inducing ligand (APRIL) expression increased at three- and six-months post-KT (p = 0.014 and p < 0.001). B-cell maturation antigen (BCMA) expression increased at six-months post-KT (p = 0.038). BAFF expression remained stable in NAR-KTRs, but was increased in CADI concerning the No-CADI group at one year (p = 0.008). BCMA expression increased in the CADI group at one- (p = 0.001) and six-years post-KT (p = 0.024). At three months, the transmembrane activator and calcium modulator interactor (TACI) gene significantly elevated KTRs with DSAs (donor-specific antibody; p = 0.034). KTRs with DSAs significantly increase the B-cell activating factor receptor (R-BAFF; p = 0.021) and TACI (p = 0.018) between pre- and three-month post-KT. Changes in the expression of the BAFF system increase during post-KTR in the development of AR and chronic allograft damage, and could be an important pathological tool to detect and prevent kidney graft outcomes.

Monitoring of Soluble Forms of BAFF System (BAFF, APRIL, sR-BAFF, sTACI and sBCMA) in Kidney Transplantation.

BAFF system plays an essential role in B cells homeostasis and tolerance, although it has widely not been tested in transplantation with doubtful results. The main purpose was to study the BAFF soluble forms and their correlation with acute rejection (AR) and donor-specific antibodies production. Serum levels of BAFF, APRIL, and soluble forms of their receptors were analyzed in renal recipients with and without acute rejection (AR/NAR) appearance. All molecules were evaluated at pre- and post-transplantation. sTACI showed a significant correlation with BAFF and sR-BAFF levels, and sBCMA also showed a positive correlation with sAPRIL levels. A significant increase in sAPRIL levels in patients suffering AR was also found, and ROC curves analysis showed an AUC = 0.724, a concentration of 6.05 ng/ml (sensitivity: 66.7%; specificity: 73.3%), the best cutoff point for predicting AR. In the post-transplant dynamics of sAPRIL levels in the longitudinal cohort, we observed a significant decrease at 3 and 6 month post-transplantation compared to pretransplantation status. We also observed that recipients with high pre-transplant levels of sAPRIL generated antibodies earlier than those with lower sAPRIL levels, although their long-term post-transplantation was not different. Our results show that elevated serum levels of APRIL may be helpful as a biomarker for the diagnosis of AR, although the longitudinal study shows that it is not helpful as a prognostic biomarker.