Anti-HLA Immunization in Patients After Lung Transplantation: A Comparative Study Before and During the Pandemic.

Anti-human leukocyte antigen (anti-HLA) sensitization in lung transplant recipients (LTRs) can significantly impact graft survival and patient outcomes. The global pandemic, induced by the SARS-CoV-2 virus, brought about numerous challenges in the medical sphere, including potential alterations in HLA immunization patterns among LTRs. A retrospective analysis of LTRs group transplanted from July 2018 to 1 March 2020 (pre-pandemic) was compared with patients transplanted from 1 March 2020 to December 2022 (during the pandemic). Totally 92 patients were controlled. Patients were also divided into 2 groups: vaccinated and non-vaccinated. The results of cytotoxic crossmatch, results of anti-HLA antibody testing, presence of DSA before and after transplantation, and early and late graft function were compared between groups. In the pandemic and vaccinated groups, an increase was observed in the number of positive crossmatch tests performed with a pool of B lymphocytes. However, the presence of dithiothreitol abolished the positive reaction in 90% of cases. We also observed an increased percentage of patients immunized based on the results of solid phase tests both in the pandemic group and in the group of patients who received vaccination against the SARS-CoV-2 virus. It might be that the pandemic/vaccination has influenced the prevalence of anti-HLA immunization in LTRs. Further studies are essential to establish causative factors and develop targeted interventions for this population of patients.

Desensitization of Highly Immunized Kidney Transplant Recipients Awaiting Transplantation-Polish Single-Center Experience.

INTRODUCTION: The increasing number of highly immunized patients waiting for kidney transplantation is a significant problem in Europe as the proportion of such patients has doubled in the last decade. Transplantation in this group is enabled by desensitization methods, i.e., intravenous pharmacotherapy with human immunoglobulin (IVIG), anti-CD20 monoclonal antibody (rituximab), and plasma exchange. The objective was to evaluate the efficacy and safety of this protocol. MATERIAL AND METHODS: The inclusion criteria: presence of established anti-HLA antibodies with complement-binding capacity, i.e., anti-HLAC1q+ (>MFI 15,000 for the most common antigens), no renal transplantation within 1 year after activation on the waiting list. Thirteen patients were selected for the procedure. IVIG was administered twice (2 g/kg-maximum 140 g/dose). Between IVIG doses, patients received rituximab (375 mg/m2). Anti-HLA was tested after 1 and 2 months after completion of the procedure. RESULTS: All patients have completed the protocol. No significant changes after desensitization in the amount/profile of alloantibodies were observed. However, with negative vCM for HLA-A/B/DR (no DSA against the reported donor) and negative CM-CDC, according to the allocation system, patients were given priority on the recipient list. Seven out of 13 patients received a transplant within 12 months after treatment (mean 11.5 weeks). Renal graft function was good (mean creatinine level after 1 month: 1.5 mg/dL). No incidents of acute rejection were reported. The most common complications were infections (especially pneumonia). CONCLUSION: The desensitization protocol (IVIG + rituximab) allows highly immunized patients to undergo organ transplantation. In short-term analysis, no acute rejection was observed, graft function was satisfactory. Desensitization was associated with an increased risk of infection.

Incidence and Role of Recipient-Specific Antibodies in Allogeneic Hematopoietic Cell Transplantation from Mismatched Related Donors.

High titer of donor-specific antibodies (DSAs) increases the risk of graft rejection after mismatched related hematopoietic cell transplantation (HCT). There are no data regarding the incidence of anti-HLA recipient-specific antibodies (RSAs) and their role after transplantation. Here we aimed to identify the incidence of RSAs in a mismatched related hematopoietic cell donor population and their possible impact on immune-mediated complications, such as acute graft-versus-host disease (aGVHD), and complications resulting from endothelial injury, such as transplantation-associated thrombotic microangiopathy (TA-TMA) and veno-occlusive disease (VOD). We prospectively analyzed the incidence of anti-HLA antibodies in 28 mismatched related pairs of recipients and their donors who underwent HCT at our center between 2020 and 2022. In positive samples screened for anti-HLA class I and/or II antibodies, the specificity of the HLA antibodies was analyzed. All recipients had a hematologic malignancy and received a myeloablative conditioning regimen and immunosuppression consisting of post-transplantation cyclophosphamide, tacrolimus, and mycophenolate mofetil. Patients were tested for TA-TMA and aGVHD development during routine post-transplantation visits up to 100 days post-transplantation. We used modified Jodele criteria for TA-TMA diagnosis, and based aGVHD grading on the MAGIC criteria. VOD was assessed using the European Society for Blood and Marrow Transplantation. Anti-HLA antibodies were detected in 12 donors (43%) and in 9 recipients (32%). There were no significant differences between donors and recipients according to age (median, 42 years [range, 17 to 69 years] versus 39 years [range, 8 to 68 years]), sex, or pregnancy history. No transfusion history was noted in the donor group (P < .05). RSA antibodies were present more often than DSAs and were detected in 9 out of 12 (75%) anti-HLA-positive donors and in only 2 out of 9 (22%) recipients, respectively (P < .05). During the follow-up, 11 patients (39%) developed aGVHD, including grade I-II in 9 (32%) and grade III-IV in 2 (7%). Twelve patients (43%) met the criteria for TA-TMA, and only 1 patient (3.5%) was diagnosed with VOD by day 100 post-HCT. RSAs were detected significantly more often in the TA-TMA group; among 12 patients diagnosed with TA-TMA, 7 (58%) had RSAs (P < .05). We did not find a correlation between RSAs and aGVHD. The patient with VOD did not have an RSA-positive donor. There was no difference in membrane attack complex (MAC) concentration in the RSA-positive group on day 30 and day 60 post-HCT; however, there was a trend toward higher MAC concentration in the RSA-positive group on day 100 (median, 912 ng/mL [range, 788 to 1120 ng/mL] versus 616 ng/mL [range, 352 to 1244 ng/mL]; P = .055). Patients with RSA suffered more often from platelet and red blood cell decreases or transfusion refractoriness, and increased lactate dehydrogenase activity was observed in all RSA-positive cases. The donor immune status and the presence of RSA may be associated with higher rates of TA-TMA in mismatched HCT recipients. Antibody-mediated complement activation might be an additional factor influencing TA-TMA occurrence.

Antibody-mediated rejection with detection of de novo donor-specific anti-human leukocyte antigen Class II antibodies after lung transplantation: Problems in diagnosis, treatment and monitoring on a case report basis.

Lung transplantation, like other transplants, carries a risk of graft rejection due to genetic differences between the donor and the recipient. In this paper, we focus on antibody-mediated rejection, which can cause acute and more importantly chronic graft dysfunction and subsequently shortened allograft survival. We present the case of a 46-year-old patient who, two months after lung transplantation (LTx), developed AMR manifested by the deterioration of graft function and de novo production of donor-specific antibodies (DSA): DQ3 (DQ7, DQ8, DQ9). As the patient was after left single LTx and heavily oxygen dependent a transbronchial biopsy was deemed to be high risk and it was decided to determine the clinical significance of the detected antibodies by their ability to bind complement. The test confirmed that the detected DSAs have the ability cause cytotoxicity of the transplanted organ. After treatment with methotrexate, intravenous immunoglobulin G (IVIg) and alemtuzumab, the patient's condition improved and a complete decrease in DSA was obtained. However, after a year, the production of antibodies increased sharply. Treatment with IVIg, cyclophosphamide and plasmapheresis slightly improved the patient's condition, reducing the MFI DSA values by half, but leaving them at high levels. Based on this clinical case, we discuss problems with making a diagnosis, choosing the right AMR treatment and monitoring the patient's condition during treatment. We also indicate a poor prognosis in the case of the production of DSA antibodies at the DQ locus.

Atopy and Multisensitizations in Specific IgE Microarrays and Their Impact on Severe Asthma.

(1) Asthma is a chronic inflammatory airway disease. Around 3-10% of patients experience severe refractory asthma. These patients with high symptom intensity and frequent exacerbations present a challenge for allergologists. Their allergic vs. non-allergic profile might be different from the standard asthmatic group and this difference is vital in qualifying for anti-IgE biologicals. The aim of the study was to analyze multiple sensitizations in patients with severe asthma and assess their impact on the course of the disease. (2) Forty-two patients with severe asthma according to GINA were enrolled. They experienced at least two exacerbations during the past year and had uncontrolled asthma despite high inhaled steroid use. A microarray serum Alex test (allergen-specific IgE to 295 extracts and components) was performed together with Complete Blood Count tests, the Asthma Control Questionnaire (ACQ), the Mini Asthma Quality of Life Questionnaire (MiniAQLQ), and spirometry. (3) There were 29 female and 13 male patients. The patient mean age was 50.4 (22-70). In 25 (60%) patients, inhalant sensitizations were detected. In 9 (21%) cases, a new perennial allergen was discovered that might enable anti-IgE treatment in the future. In the entire studied group, 8 patients (19%) would still not qualify for anti-IgE, anti-IL4, or anti-IL5 treatment. A linear regression analysis revealed that a Canis familiaris allergen (Can f 1) correlated with worse asthma control in ACQ. An Aspergillus allergen (Asp f 6) correlated negatively with Forced Expiratory Volume in one second (FEV1). (4) The study presents the usefulness of the ALEX test in 21% of patients with severe asthma in qualification for anti-IgE treatment. It highlights the impact of canine and Aspergillus sensitizations on worse control in patients with severe asthma.

In-Depth Analysis of Anti-HLA Antibodies Using C1q Assay.

Alloantibodies are significant biomarkers of posttransplant kidney rejection. With solid-phase assays, the presence of alloantibodies and complement-binding capacities can be tested. It has been noted that complement-binding anti-HLA (C1q) correlates well with high titers of anti-HLA antibodies (single antigen bead, SAB), but we have recently shown that lower SAB titers may be associated with complement in the complement cytotoxicity test. If so, low titers of donor-specific antibodies could be stratified for complement binding and used for better donor-recipient matching. To study this, we tested 268 patients awaiting kidney transplantation for SAB and C1q and stratified them into positive (Allo+) and negative (Allo-) cohorts. Next, all assayed specificities of SAB were matched with the corresponding C1q in order to correlate mean fluorescence intensity levels. We found a strong correlation between SAB and C1q for all HLA loci apart from HLA-DP. Moreover, there was no strict cutoff for C1q prediction on SAB mean fluorescence intensity level. In addition, an unusual laboratory phenotype was found; that is, a positive C1q result without corresponding SAB specificity. We tested this phenomenon and found positive IgM SAB. CONCLUSIONS: Simultaneous C1q and SAB testing may serve as a tool for in-depth analysis of alloantibodies before transplantation.

Anti-HLA immunization of patients qualified for lung transplantation - Single center study.

For lung transplantation, the presence of donor-specific anti-HLA antibodies (DSA) is an important factor of antibody-mediated rejection (AMR) in its hyperacute, acute or chronic form during long-term follow up. The aim of the study was to assess the allosensitization of Polish patients qualified for a lung transplantation in our center. A retrospective study of 161 potential lung allograft recipients, also of 31 patients transplanted in the University Hospital of Gdansk, between June 2018 and December 2020 were performed. 121 potential recipients were thoroughly tested for immunization status before eventual lung transplantation. SAB-testing, PRA-CDC and vPRA assessment, and HLA typing were performed to guide donor-recipient matching and risk stratification. Then 73 patients were separated and qualified for the list of patients awaiting lung transplantation. Then 31 patients were transplanted based on a negative biological crossmatch result. The patients were generally not sensitized, as the median PRA-CDC was 0% (min 0; max 53), and the vPRA, calculated according to HLA ABDR (>2000 cut-off MFI), was 8% (min 0; max 99). If the cut-off was split into 2000 MFI for HLA ABDR, 10,000 MFI for HLAC, and 7000 MFI for HLA-DQ, the vPRA increased to 20% (min 0; max 99). The immunization status was assessed with single antigen-SAB assays. For class I, the number of any detectable alloantibodies was 14 (11.6%) 21 (17.35%) 16 (13.22%) for locus HLA-A/B/C, and 28 (23.14%) 30 (24.8%) 24 (19.8%) for locus HLA-DR/DQ/DP, respectively. The immunization of the transplanted patients was then analyzed in detail. Summarizing, the study is an analysis of the degree of anti-HLA immunization in the population of patients eligible for lung transplantation, which showed that this degree is of low intensity and can be effectively and safely and very precisely diagnosed before transplantation.

CD5-Positive B Lymphocytes after Kidney Transplantation.

Kidney transplantation is the treatment of choice for end-stage kidney diseases. Unfortunately, kidney allograft recipients rarely develop tolerance or accommodation and require life-long immunosuppression. Among many other regulatory mechanisms, CD5+ B lymphocytes (mainly B-1a) seem to be involved in the process of allograft acceptance. These cells are the major source of natural, low-affinity antibodies, which are polyreactive. Thus, we hypothesized that CD5+ B cells could be referred to as a biomarker in those patients who developed accommodation towards kidney allotransplant. In this study, 52 low-immunized kidney transplant recipients were evaluated for transplant outcome up to 8 y post-transplant. The follow up included anti-HLA antibodies, B cells phenotype and cytokines. We have identified a cohort of recipients who produced alloantibodies (Abs+), which was associated with increased levels of CD5+ B cells, mainly during the first year after transplantation but also later on. Importantly, creatinine levels were comparable between Abs+ and Abs- allorecipients at 2 years after the transplantation and graft survival rate was comparable between these groups even eight years post-transplant. So, it seems that despite the presence of alloantibodies the graft function was sustained when the level of CD5+ B cells was increased. Targeting CD5+ B cells may be a valuable therapeutic option to increase transplant success. The phenotype can be also tried as a biomarker to increase the effectiveness of individualized post-transplant treatments.

KIR Receptors as Key Regulators of NK Cells Activity in Health and Disease.

Natural killer (NK) cells are part of the cellular immune response. They target mainly cancer and virally infected cells. To a high extent cytotoxic activity of NK cells is regulated inter alia by signals from killer immunoglobulin-like receptors (KIR). The major histocompatibility complex (MHC) class I molecules are important ligands for KIR receptors. Binding of ligands (such as MHC I) to the KIR receptors has the important role in solid organ or hematopoietic cell transplantation. Of note, the understanding of the relationship between KIR and MHC receptors may contribute to the improvement of transplant results. Donor-recipient matching, which also includes the KIR typing, may improve monitoring, individualize the treatment and allow for predicting possible effects after transplantation, such as the graft-versus-leukemia effect (GvL) or viral re-infection. There are also less evident implications of KIR/MHC matching, such as with pregnancy and cancer. In this review, we present the most relevant literature reports on the importance of the KIR/MHC relationship on NK cell activity and hematopoietic stem cell transplantation (HSCT)/solid organ transplantation (SOT) effects, the risk of allograft rejection, protection against post-transplant cytomegalovirus (CMV) infection, pregnancy complications, cancer and adoptive therapy with NK cells.

The utility of cytolytic flow cytometry crossmatch before kidney transplantation.

The donor/recipient matching in kidney transplantation is based on approved laboratory tests, which are complement-dependent cytotoxic crossmatch (CDC-XM) and flow cytometry crossmatch (FCXM). Both have some disadvantages: CDC-XM has low sensitivity, whereas FCXM does not differentiate between lytic vs. non-lytic alloantibodies. To find an improved method, we have developed a new crossmatch technique of cytolytic flow cytometry crossmatch (cFCXM), which allows for sensitive detection of clinically relevant complement-binding antibodies. The cFCXM assay detects dead cells with viability dye that ensue from the binding of allospecific lytic antibodies. In our study, 135 unsensitized kidney transplant recipients were recruited based on the CDC-XM and FCXM results and the clinical utility of cFCXM was evaluated. The 5-year follow-up for acute rejection incidents revealed that cFCXM could verify the clinical relevance of positive FCXM results as recipients with positive FCXM but negative CDC-XM had the same risk of rejection as patients with both negative CDC-XM/FCXM results. These findings suggest that cFCXM assay may provide more precise immunological risk assessment in kidney transplant recipients.

Immune Algorithm Optimization for Organ Transplantation in Poland.

The lack of a uniform method for determining unacceptable HLA mismatches (UAMs) for organ transplantation worldwide has resulted in many different algorithms for donor-recipient matching. Here we present our proposal for changes to the current algorithm for immune evaluation of potential kidney recipients in Poland based on the experience of various transplantation centers. The most important finding of this article is an algorithm that stratifies the pretransplant immunologic risk based on strict laboratory criteria, enabling harmonization between transplant centers in Poland. This is because of a step-by-step algorithm for alloantibody assessment using solid-phase assays (SPA) and clearly defined technical issues, as well as cutoffs for reporting UAMs. Our novel approach focuses on a laboratory testing extension in the scope of HLA typing; detection and characterization of alloantibodies before transplantation; desensitization; and post-transplant monitoring. The proposed changes will allow for the assessment of clinically relevant anti-HLA antibodies with complement binding properties; the determination of UAMs in the potential donor; the calculation of virtual panel reactive antibodies (vPRA); the calculation of the recipient's immunologic rejection risk stratification; the assessment of the donor-recipient virtual cross-match (vXM); and the determination of the final recipient's selection for the biological cross-match testing. Collectively, the optimized algorithm permit for UAM verification is based on laboratory proofed data and will firmly improve organ allocation and transplant outcomes in Poland. We hope that this novel approach also improves the individual patient's risk stratification and future personalized treatment.

Proinsulin-specific T regulatory cells may control immune responses in type 1 diabetes: implications for adoptive therapy.

OBJECTIVE: Here we looked for possible mechanisms regulating the progression of type 1 diabetes mellitus (T1DM). In this disease, autoaggressive T cells (T conventional cells, Tconvs) not properly controlled by T regulatory cells (Tregs) destroy pancreatic islets. RESEARCH DESIGN AND METHODS: We compared the T-cell compartment of patients with newly diagnosed T1DM (NDT1DM) with long-duration T1DM (LDT1DM) ones. The third group consisted of patients with LDT1DM treated previously with polyclonal Tregs (LDT1DM with Tregs). We have also looked if the differences might be dependent on the antigen specificity of Tregs expanded for clinical use and autologous sentinel Tconvs. RESULTS: Patients with LDT1DM were characterized by T-cell immunosenescence-like changes and expansion of similar vß/T-cell receptor (TCR) clones in Tconvs and Tregs. The treatment with Tregs was associated with some inhibition of these effects. Patients with LDT1DM possessed an increased percentage of various proinsulin-specific T cells but not GAD65-specific ones. The percentages of all antigen-specific subsets were higher in the expansion cultures than in the peripheral blood. The proliferation was more intense in proinsulin-specific Tconvs than in specific Tregs but the levels of some proinsulin-specific Tregs were exceptionally high at baseline and remained higher in the expanded clinical product than the levels of respective Tconvs in sentinel cultures. CONCLUSIONS: T1DM is associated with immunosenescence-like changes and reduced diversity of T-cell clones. Preferential expansion of the same TCR families in both Tconvs and Tregs suggests a common trigger/autoantigen responsible. Interestingly, the therapy with polyclonal Tregs was associated with some inhibition of these effects. Proinsulin-specific Tregs appeared to be dominant in the immune responses in patients with T1DM and probably associated with better control over respective autoimmune Tconvs. TRIAL REGISTRATION NUMBER: EudraCT 2014-004319-35.

Impact of donor and recipient human cytomegalovirus status on kidney transplantation.

Human cytomegalovirus (HCMV) is considered to be a major pathogen that affects the outcome of solid organ transplantation (TX). Both recipient and donor may be HCMV positive, therefore HCMV re-infection is possible after TX. However, little is known how cytomegalovirus (CMV) transmitted from an infected donor to an infected recipient modulates the recipient's already suppressed immunity, and what the clinical consequences are. To investigate these issues, 52 kidney recipients were followed up for 2 years after TX. T, B and natural killer (NK) lymphocytes, naive and memory T subsets, CD28 expression, relative telomere length, CMV-specific lymphocytes and serum cytokines were measured several times post-TX. Patients were monitored for signs of CMV viremia and other infections. The most important observation was that CMV-specific lymphocytes expand vastly in HCMV-infected recipients who received kidneys from infected donors, in comparison with uninfected donors. Despite this, a higher rate of HCMV viremia was found. Immune deterioration was confirmed by an increased number of CD28-negative T lymphocytes, inverted CD4/CD8 index and shortened telomeres. This was superior in HCMV-infected recipients transplanted from infected donors, when compared with uninfected. In conclusion, CMV alters the immune system in kidney transplant recipients and promotes immune exhaustion.

Association of cytokine gene polymorphisms with the complications of allogeneic haematopoietic stem cell transplantation.

The purpose of our study was to confirm the prevalence of the association between single nucleotide polymorphisms present in genes encoding cytokines and the complications occurring after haematopoietic stem cell transplantation (HSCT). 108 recipients and 81 donors were typed for TNF-α (-308), TGF-ß1 (codon 10, 25), IL-10 (-1082, -819, -592), IL-6 (-174) and INF-γ (+874). Our studies have shown a tendency toward association between the occurrence of acute form of graft versus host disease (aGVHD) and IL-6 genotype. Homozygote C/C was less likely to develop aGVHD (p=0,09). Genotype GCC/ATA in IL-10 recipient gene alone had protective effect against the occurrence of aGVHD (p=0,01). Furthermore, GCC/ATA protected the host against developing the disease in the clinically relevant grades (II-IV) (p=0,03). In addition, the recipient's T/T G/G genotype (TGF-ß1) predisposed to the development of both acute (p=0,06 - trend) and chronic (p=0,04) GVHD and also severe aGVHD (p=0,004). We also observed a statistically significant association between the genotype of recipient and the risk of infection - the protective function of the G/C IL-6 in the bloodstream infections (p=0,001). Our results suggest that IL-6, IL-10 and TGF-ß1 genotypes of recipient are the most associated with the risk of complications after HSCT.

Epidemiology, risk factors and prognosis of Interferon alpha induced thyroid disorders. A Prospective Clinical Study.

INTRODUCTION: Hepatitis C virus (HCV) infection is a worldwide problem and hepatitis, which is its natural unfavourable course, is still a challenge for hepatologist. At present, standards of treatment are changing from combined therapy with interferon alpha (IFN-α) and ribavirin to new antiviral drugs. The current classification divides interferon induced thyroid diseases (IITD) into two groups: autoimmune (Hashimoto disease, Graves disease, positive antithyroid autoantibodies in euthyroid patients) and non-autoimmune (destructive thyroiditis, non-autoimmune hypothyroidism). A common complication of cytokine therapy is the induction of antithyroid autoantibodies de novo without thyroid dysfunction. During therapeutic regimens combined with ribavirin, destructive thyroiditis with typical biphasic course is more common than in IFN-α monotherapy. Clinically, overt pathologies often have discrete symptoms, which cause diagnostic and therapeutic dilemmas. AIMS: The aim of this study was to estimate IITD occurrence, to find risk factors for IITD development. MATERIAL AND METHODS: The study group consisted of 66 patients treated for HCV infection. Before and during antiviral therapy, hormonal (TSH, fT4, fT3), immunological (thyroid autoantibodies), ultrasonographic and genetic (HLA-A2) parameters were evaluated. RESULTS: Hormonal disturbances were detected in 24.2% of patients; however, 43.9% of patients had positive thyroid autoantibodies (de novo) without hormonal imbalance. Multivariate analysis revealed the following: female sex, elevated TSH level, occurrence of anti-TPO autoantibodies (TPO-Ab), and increased blood velocity in thyroid arteries are risk factors for IITD development. IN CONCLUSION: Thyroid disorders are common during IFN-α therapy. Previous epidemiological data seem to be underestimated. Important risk factors for IITD development are: female sex, elevated serum TSH concentration (≥2.5 µU/mL), positive TPO-Ab and increased blood velocity in thyroid arteries.

CD28 positive, cytomegalovirus specific cytotoxic T lymphocytes as a novel biomarker associated with cytomegalovirus viremia in kidney allorecipients.

BACKGROUND: CMV infection remains major complication after kidney transplantation, thus diagnostics tools that would improve identification of individuals at risk of development of CMV - related complications are useful. For this reason, searching for proper immunological biomarkers candidates gives hope to individualize antiviral therapy and minimize side effects of antiviral drugs. OBJECTIVES: The purpose of this research was to assess immune assays that can be used to predict the likelihood of CMV viremia after kidney allotransplantation. STUDY DESIGN: In the study, immunological markers of CMV viremia were assessed in 52 kidney transplant recipients during two years lasting follow-up. Immunological markers associated with viral infection, like lymphocytosis, cytotoxic T lymphocytes (CTL) and serum cytokines levels were compared with less common immunological assays, like activated T lymphocytes, CMV-specific CTL stratified according to naïve/memory phenotype. The test to assess expression of CD28 antigen on CTL, as a possible additional marker of CMV-specificity, was developed. RESULTS: CD28-positive CMV-specific CTL have been found the most useful marker for CMV viremia prediction. Tested value of 3 cells/µl was found to be most suitable for CMV activation assessment with acceptable sensitivity and specificity. DISCUSSION: This preliminary report suggests that CD28-positive CMV-specific CTL could be put at the first line, as possible novel marker associated with CMV viremia development.

Identification of patients with increased immunological risk among potential kidney recipients in the Polish population.

Pretransplant identification of allosensitized patients is possible thanks to new technologies, which allow for accurate detection of clinically relevant alloantibodies. Implementation of these methods in the screening of patients awaiting transplantation increased their chance for successful donor-recipient matching. Here, 1460 patients reported to the Polish National Waiting List were screened with the Luminex Screen (LS) solid phase test for anti-HLA antibodies. The patients with detected anti-HLA antibodies were assayed with the Luminex Single Antigen (LSA) tests in order to establish defined antigen specificity of the alloantibodies. The results were compared with data on the immunization assessed with the routine complement-dependent-cytotoxicity panel-reactive-antibody assay (PRA CDC). The study showed significantly higher sensitivity of the LS method when compared with PRA CDC. It has been shown that LSA test is a useful technique identifying the specificities of alloantibodies. In particular, LSA allowed to assess donor specific antibodies (DSA) to previous mismatches (MM) and to determine acceptable HLA mismatches of the potential donors. The introduction of solid phase tests in routine pretransplant diagnostics allowed for faster and more accurate assessment of the immunological risk of the recipients and optimal donor-recipient matching. Hence, the presented algorithm of solid phase assays has become a new standard for the identification of allosensitized patients awaiting kidney transplantation in Poland.

Immunosenescence increases the rate of acceptance of kidney allotransplants in elderly recipients through exhaustion of CD4+ T-cells.

Compromised immunity is the hallmark of ageing. Paradoxically, it may be "an ally" in facilitating acceptance of allogeneic grafts in the elderly. In this retrospective study we looked for biomarkers of immunosenescence that distinguish elderly recipients less prone to reject kidney allografts. Recruited kidney recipients aged > or = 60 or < 60 were designated 'elderly' and 'young', respectively. Both age-groups were divided according to the history of acute rejection. The phenotype, length of telomeres, expression of FoxP3 and proliferative responses were assessed in CD4(+) and CD8(+) T-cell subsets. In addition, IL6, IL10 and TGFbeta were measured on the level of mRNA and serum protein. Acute-rejection-free history in elderly transplant recipients was associated with short telomeres, a decreased proportion of CD28(+) T-cells associated with CMV-seropositivity and low proliferation of CD4(+) T-cells. In contrast, elderly recipients who experienced acute rejection kept preserved telomere length, had a higher number of functional CD4(+)CD28(+) cells and exhibited vigorous proliferation in vitro. These differences were not found in the young group. The major conclusion of this study is that the impaired condition of CD4(+) T-cells, so-called immunosenescence, renders transplant recipients less responsive to an allogeneic kidney graft, an effect that was limited to transplant recipients of > 60 years of age.

[Diagnostic value of specific anty-HLA alloantibodies before and after renal transplantation. Programs for highly sensitized recipients]. / Znaczenie diagnostyczne swoistych aloprzeciwcial anty-HLA u chorych przed i po transplantacji nerek. Programy dla wysoko zimmunizowanych.

Anti-HLA alloantibodies are the main barrier in kidney transplantation. Lack of appropriate donors for highly sensitized (HS) recipients makes access to transplantation very difficult and results in a significant increase in both the time on the waiting list and the number of post-transplant complications in these patients. The transplantation itself is also associated with higher risk in the HS. There are many programs aimed at increasing access to renal transplantation for this group of recipients. It is noteworthy that new acceptable HLA-mismatches allowed significant progress in programs for HS recipients. Currently implemented programs (ET-AMP, UNOS, Emory algorithm) proved useful as they increased access to transplantation and graft survival in HS patients. Nevertheless, even with these programs there is still the problem of humoral rejection in these patients. The strong correlation between donor-specific antibodies (DSA) and graft rejection seen both immediately after transplantation and in long-term complications such as CAN (chronic allograft nephropathy) may be the simplest explanation for this effect. Hence the assessment of alloantibodies limited to the pre-transplant period, which is nowadays routine, seems insufficient. Current evidence suggests that early detection of post-transplant DSA may be an excellent prognostic marker of graft function and may allow implementing the necessary treatment prior to rejection.

DQA1*03011 allele: protective or an adverse effect on the development of sarcoidosis; preliminary study.

BACKGROUND: Sarcoidosis (SA) is a multisystem granulomatous disorder of unknown etiology. It seems likely that in genetically different predisposed hosts, the same antigen(s) may cause the development of sarcoid Th1 response. The interaction of the T-cell receptor with the human leukocyte antigen-DQA1*03011 peptide-complex can affect T lymphocytes activation in a dose-response manner. OBJECTIVES/METHODS: To test occurrence of DQA1*03011 allele in SA, we compared the distribution of DQA1 alleles in 32 SA patients, 37 TB patients and in 58 healthy volunteers, using a PCR-SSP "high-resolution" method. RESULTS: Our results revealed that after Bonferroni correction DQA1*03011 were less common in SA patients than in the controls (OR 0.16, 95%CI 0.03-0.75). In TB, DQA1*0303 were significantly more frequent and DQA1*0505 less present as compared to the controls (OR 11.03, 95% CI 1.20-95.80, OR 0.29, 95% CI 0.01-0.88). Comparing DQA1 alleles in both patient groups, DQA1*0501, DQA1*0505 alleles were more common and DQA1*03011, DQA1*0302, DQA1*0303 were less common after Bonferroni correction in SA than in TB. CONCLUSION: We revealed that DQA1*03011 allele was less common in SA than in the controls and TB. It seems possible that a low frequency of DQA1*03011 occurrence may be also involved in the etiopathogenesis of SA.