Biology subjects

Nicosia, M.

Publications and source records attributed to Nicosia, M..

3 recordsLinked to original sources

bioRxiv2025

Inhibition of De Novo Autoantibody Production Attenuates Chronic Antibody-Mediated Rejection of Kidney Allografts Despite Maintenance of High Donor-Specific Antibody Titers

Acute and chronic antibody mediated rejection (ABMR) continues to decrease clinical kidney graft function and survival. Dysregulated donor-specific antibody (DSA) responses are induced in B6.CCR5-/- recipients of complete MHC-mismatched A/J kidney allografts with NK cells playing a critical role in the acute ABMR. We tested the role of neutrophils in ABMR by transplanting A/J kidneys to CCR5-/- mice with a deletion in the neutrophil serine protease cathepsin G. Whereas B6.CCR5-/- recipients rejected all kidney allografts between days 18-25, 70% of allografts survived beyond day 60 in B6.CCR5-/-cG-/- recipients. At days 15-17 post-transplant DSA titers in B6.CCR5-/-cG-/- recipients were 24.3-fold higher than those in wild-type C57BL/6 allograft recipients. Allografts from B6.CCR5-/-cG-/- recipients on days 45 and 60 had typical characteristics of chronic graft injury including interstitial collagen deposition and peri-glomerular fibrosis that was accompanied by a fibrogenic transcript signature and late post-transplant production of autoantibodies to many targets, including structural proteins including collagen IV and fibronectin. Depletion of B cells at the time DSA peak titers were achieved on day 14 post-transplant decreased serum autoantibodies levels, the kidney allograft fibrogenic transcript signature, and the chronic kidney allograft injury, despite maintenance of the high DSA titers. These results indicate a critical role for neutrophil cathepsin G during acute ABMR of kidney allografts and in its absence, DSA induced late appearance of autoantibodies mediating development of chronic kidney allograft injury.

immunology↗

bioRxiv2022

Sex-specific T cell exhaustion drives differential immune responses in glioblastoma

Sex differences in glioblastoma (GBM) incidence and outcome are well recognized, and emerging evidence suggests that these extend to genetic/epigenetic and cellular differences, including immune responses. However, the mechanisms driving immunological sex differences are not fully understood. Using GBM models, we demonstrate that T cells play a critical role in driving GBM sex differences. Male mice exhibited accelerated tumor growth, with decreased T cell infiltration and increased T cell exhaustion. Furthermore, a higher frequency of progenitor exhausted T cells was found in males, with improved responsiveness to anti-PD1 treatment. Bone marrow chimera and adoptive transfer models indicated that T cell-mediated tumor control was predominantly regulated in a cell-intrinsic manner, which was further corroborated by in vitro exhaustion assays. Moreover, increased T cell exhaustion was observed in male GBM patients. These findings demonstrate sex-specific pre-determined behavior of T cells is critical in inducing sex differences in GBM progression and immunotherapy response. Statement of significanceImmunotherapies in GBM patients have been unsuccessful due to a variety of factors including the highly immunosuppressive tumor microenvironment in GBM. This study demonstrates that sex-specific T cell behaviors are predominantly intrinsically regulated, further suggesting sex-specific approaches can be leveraged to potentially improve therapeutic efficacy of immunotherapy in GBM.

immunology↗

bioRxiv2022

Recipient LAG3 deficiency results in antibody-mediated rejection of mouse renal allografts

Lymphocyte activation gene-3 (LAG3) is a coinhibitory receptor expressed by a range of immune cells. While immunomodulatory potential of LAG3 is being actively explored in cancer and autoimmunity fields, there is no information on how this pathway affects alloreactive immune responses following organ transplantation. The goal of this study was to investigate the functions of recipient LAG3 in a mouse model of renal allograft rejection. We found that mice deficient in LAG3 expression have elevated heterologous immunity against a panel of alloantigens prior to transplantation. Recipient LAG3 deficiency results in rapid rejection of MHC-mismatched renal allografts that are spontaneously accepted by WT recipients, with graft histology characteristic of antibody mediated rejection (ABMR). Depletion of recipient B cells but not CD8+ T cells significantly extended kidney allograft survival in LAG3-/- recipients further supporting ABMR as the main mechanism of graft loss. Treatment of WT recipients with an antagonistic LAG3 antibody enhanced anti-donor immune responses and induced kidney damage associated with chronic rejection. The experiments using conditional LAG3 knockout recipients demonstrated that LAG3 expression on either T or B cells is sufficient to regulate anti-donor humoral immunity. These results are the first to identify LAG3 as a regulator of both T and B cell responses to kidney allografts and a potential therapeutic target for ABMR prevention and treatment.

immunology↗