@article{LauruschkatMuchsinReinetal.2023, author = {Lauruschkat, Chris David and Muchsin, Ihsan and Rein, Alice and Erhard, Florian and Grathwohl, Denise and D{\"o}lken, Lars and K{\"o}chel, Carolin and Falk, Christine Susanne and Einsele, Hermann and Wurster, Sebastian and Grigoleit, G{\"o}tz Ulrich and Kraus, Sabrina}, title = {CD4+ T cells are the major predictor of HCMV control in allogeneic stem cell transplant recipients on letermovir prophylaxis}, series = {Frontiers in Immunology}, volume = {14}, journal = {Frontiers in Immunology}, doi = {10.3389/fimmu.2023.1148841}, url = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-316982}, year = {2023}, abstract = {Introduction Human cytomegalovirus (HCMV) causes significant morbidity and mortality in allogeneic stem cell transplant (alloSCT) recipients. Recently, antiviral letermovir prophylaxis during the first 100 days after alloSCT replaced PCR-guided preemptive therapy as the primary standard of care for HCMV reactivations. Here, we compared NK-cell and T-cell reconstitution in alloSCT recipients receiving preemptive therapy or letermovir prophylaxis in order to identify potential biomarkers predicting prolonged and symptomatic HCMV reactivation. Methods To that end, the NK-cell and T-cell repertoire of alloSCT recipients managed with preemptive therapy (n=32) or letermovir prophylaxis (n=24) was characterized by flow cytometry on days +30, +60, +90 and +120 after alloSCT. Additionally, background-corrected HCMV-specific T-helper (CD4+IFNγ+) and cytotoxic (CD8+IFNγ+CD107a+) T cells were quantified after pp65 stimulation. Results Compared to preemptive therapy, letermovir prophylaxis prevented HCMV reactivation and decreased HCMV peak viral loads until days +120 and +365. Letermovir prophylaxis resulted in decreased T-cell numbers but increased NK-cell numbers. Interestingly, despite the inhibition of HCMV, we found high numbers of "memory-like" (CD56dimFcεRIγ- and/or CD159c+) NK cells and an expansion of HCMV-specific CD4+ and CD8+ T cells in letermovir recipients. We further compared immunological readouts in patients on letermovir prophylaxis with non/short-term HCMV reactivation (NSTR) and prolonged/symptomatic HCMV reactivation (long-term HCMV reactivation, LTR). Median HCMV-specific CD4+ T-cell frequencies were significantly higher in NSTR patients (day +60, 0.35 \% vs. 0.00 \% CD4+IFNγ+/CD4+ cells, p=0.018) than in patients with LTR, whereas patients with LTR had significantly higher median regulatory T-cell (Treg) frequencies (day +90, 2.2 \% vs. 6.2 \% CD4+CD25+CD127dim/CD4+ cells, p=0.019). ROC analysis confirmed low HCMV specific CD4+ (AUC on day +60: 0.813, p=0.019) and high Treg frequencies (AUC on day +90: 0.847, p=0.021) as significant predictors of prolonged and symptomatic HCMV reactivation. Discussion Taken together, letermovir prophylaxis delays HCMV reactivation and alters NK- and T-cell reconstitution. High numbers of HCMV-specific CD4+ T cells and low numbers of Tregs seem to be pivotal to suppress post-alloSCT HCMV reactivation during letermovir prophylaxis. Administration of more advanced immunoassays that include Treg signature cytokines might contribute to the identification of patients at high-risk for long-term and symptomatic HCMV reactivation who might benefit from prolonged administration of letermovir.}, language = {en} } @article{MarischenEnglertSchmittetal.2018, author = {Marischen, Lothar and Englert, Anne and Schmitt, Anna-Lena and Einsele, Hermann and Loeffler, Juergen}, title = {Human NK cells adapt their immune response towards increasing multiplicities of infection of Aspergillus fumigatus}, series = {BMC Immunology}, volume = {19}, journal = {BMC Immunology}, number = {39}, doi = {10.1186/s12865-018-0276-6}, url = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-176331}, year = {2018}, abstract = {Background: The saprophytic fungus Aspergillus fumigatus reproduces by generation of conidia, which are spread by airflow throughout nature. Since humans are inhaling certain amounts of spores every day, the (innate) immune system is constantly challenged. Even though macrophages and neutrophils carry the main burden, also NK cells are regarded to contribute to the antifungal immune response. While NK cells reveal a low frequency, expression and release of immunomodulatory molecules seem to be a natural way of their involvement. Results: In this study we show, that NK cells secrete chemokines such as CCL3/MIP-1α, CCL4/MIP-1β and CCL5/RANTES early on after stimulation with Aspergillus fumigatus and, in addition, adjust the concentration of chemokines released to the multiplicity of infection of Aspergillus fumigatus. Conclusions: These results further corroborate the relevance of NK cells within the antifungal immune response, which is regarded to be more and more important in the development and outcome of invasive aspergillosis in immunocompromised patients after hematopoietic stem cell transplantation. Additionally, the correlation between the multiplicity of infection and the expression and release of chemokines shown here may be useful in further studies for the quantification and/or surveillance of the NK cell involvement in antifungal immune responses.}, language = {en} } @article{WilhelmSmetakSchaeferEckartetal.2014, author = {Wilhelm, Martin and Smetak, Manfred and Schaefer-Eckart, Kerstin and Kimmel, Brigitte and Birkmann, Josef and Einsele, Hermann and Kunzmann, Volker}, title = {Successful adoptive transfer and in vivo expansion of haploidentical γδ T cells}, series = {Journal of Translational Medicine}, volume = {12}, journal = {Journal of Translational Medicine}, number = {45}, doi = {10.1186/1479-5876-12-45}, url = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-117290}, year = {2014}, abstract = {Background: The primary aim of this pilot study was to determine the feasibility and safety of an adoptive transfer and in vivo expansion of human haploidentical gamma delta T lymphocytes. Methods: Patients with advanced haematological malignancies who are not eligible for allogeneic transplantation received peripheral blood mononuclear cells from half-matched family donors. For that, a single unstimulated leukapheresis product was incubated with both the anti-CD4 and anti-CD8 antibodies conjugated to paramagnetic particles. The depletion procedure was performed on a fully automated CliniMACS (R) device according to the manufacturer's instructions. On average, patients received 2.17 x 10(6)/kg (range 0.9-3.48) γδ T cells with <1\% CD4-or CD8-positive cells remaining in the product. All patients received prior lymphopenia-inducing chemotherapy (fludarabine 20-25 mg/m(2) day -6 until day -2 and cyclophosphamide 30-60 mg/kg day -6 and -5) and were treated with 4 mg zoledronate on day 0 and 1.0x10(6) IU/m(2) IL-2 on day +1 until day +6 for the induction of gamma delta T cell proliferation in vivo. Results: This resulted in a marked in vivo expansion of donor γδ T cells and, to a lower extent, natural killer cells and double-negative αβ T cells (mean 68-fold, eight-fold, and eight-fold, respectively). Proliferation peaked by around day +8 and donor cells persisted up to 28 days. Although refractory to all prior therapies, three out of four patients achieved a complete remission, which lasted for 8 months in a patient with plasma cell leukaemia. One patient died from an infection 6 weeks after treatment. Conclusion: This pilot study shows that adoptive transfer and in vivo expansion of haploidentical γδ T lymphocytes is feasible and suggests a potential role of these cells in the treatment of haematological diseases.}, language = {en} }