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Background: Data about vaccine efficacy in solid organ transplant patients are limited. We previously reported our initial observation of a 6.2% immunogenicity rate in kidney transplant recipients (KTRs) after administration of 1 dose of the severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) mRNA vaccine. We sought to report our observations of anti-SARS-CoV-2 antibody in KTRs after 2 doses of the SARS-CoV-2 mRNA vaccine., Methods: We identified 105 KTRs who received 2 doses of the Pfizer-BioNTech or Moderna mRNA-1273 vaccine per availability and had anti-SARS-CoV-2 labs obtained at least 2 wk following administration of the second dose. Antibody testing was performed using 3 clinically validated qualitative and semiquantitative assays., Results: KTRs had a 36.2% antibody response rate, whereas an age ≥68 years and a longer time from transplant were factors associated with antibody response., Conclusions: The low antibody response in KTRs may be associated with the immunosuppressive state. More data are needed to evaluate if KTRs may require higher vaccine doses or an additional booster dose to increase their ability to mount an immune response to the SARS-CoV-2 vaccine., Competing Interests: The authors declare no funding or conflicts of interest., (Copyright © 2021 The Author(s). Transplantation Direct. Published by Wolters Kluwer Health, Inc.)

The newly emerged severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) highlights the urgent need for assays that detect protective levels of neutralizing antibodies. We studied the relationship among anti-spike ectodomain (anti-ECD), anti-receptor-binding domain (anti-RBD) IgG titers, and SARS-CoV-2 virus neutralization (VN) titers generated by 2 in vitro assays using convalescent plasma samples from 68 patients with COVID-19. We report a strong positive correlation between both plasma anti-RBD and anti-ECD IgG titers and in vitro VN titers. The probability of a VN titer of ≥160, the FDA-recommended level for convalescent plasma used for COVID-19 treatment, was ≥80% when anti-RBD or anti-ECD titers were ≥1:1350. Of all donors, 37% lacked VN titers of ≥160. Dyspnea, hospitalization, and disease severity were significantly associated with higher VN titer. Frequent donation of convalescent plasma did not significantly decrease VN or IgG titers. Analysis of 2814 asymptomatic adults found 73 individuals with anti-ECD IgG titers of ≥1:50 and strong positive correlation with anti-RBD and VN titers. Fourteen of these individuals had VN titers of ≥1:160, and all of them had anti-RBD titers of ≥1:1350. We conclude that anti-RBD or anti-ECD IgG titers can serve as a surrogate for VN titers to identify suitable plasma donors. Plasma anti-RBD or anti-ECD titers of ≥1:1350 may provide critical information about protection against COVID-19 disease.

Parkinson's disease (PD) is a progressive neurodegenerative disorder associated with the loss of catecholaminergic neurons in several brain regions. The motor symptoms of the disease are related to degeneration of the midbrain dopaminergic neurons, which occurs some time after the disease has begun. Both the innate and adaptive immune systems appear to play a role in the neurodegenerative process, and may contribute to disease progression. Here we review the neuropathology of PD with attention focused on the involvement of the innate immune cells (microglia) and the adaptive immune cells (T lymphocytes). In addition, we discuss animal models of the disease with emphasis on a progressive rat model which allows a detailed analysis of how the immune system contributes to neurodegeneration both during early and late stages of degeneration. Finally, for the early detection and treatment of PD, we discuss immunotherapy approaches.

Acridine-iminodibenzyl chimeric compounds were previously introduced as a class of cholesterol-redistributing substances with antiprion effects. Here, we show that administration of the lead compound quinpramine to mice with experimental autoimmune encephalitis, an animal model of multiple sclerosis (MS), significantly ameliorates disease in preventive and therapeutic paradigms. Quinpramine treatment decreased the number of inflammatory CNS lesions, antigen-specific T-cell proliferation, and pro-inflammatory cytokines IFNgamma and IL-17. Quinpramine is thus an immunoregulatory drug that is a candidate pharmaceutical for MS.

Multiple sclerosis is widely recognized as the most commonly identified cause of progressive neurologic disability in young adults throughout the developed world. The disorder is clinically suspected when patients experience either acute attacks of neurologic compromise or instead are afflicted by a steadily progressive deterioration in functional capabilities. The pathophysiology of acute exacerbations is thought to be related to the development of inflammation and its consequences, within strategic and often discrete central nervous system tract systems. Although a myriad of hypotheses have been formulated to explain the underpinnings of the mechanisms that contribute to both the predilection and triggering of the multiphasic inflammatory events that personify multiple sclerosis, much remains to be done to understand fully the specific set and sequence of events that produce the disease and its cardinal features.

B7/CD28-mediated costimulation is a promising target for therapeutic intervention in autoimmune diseases. However, studies addressing the differential functional roles of B7-1 and B7-2 in several autoimmune models have resulted in conflicting data, perhaps due to the temporal dynamics of B7-1 and B7-2 surface expression on different cell types and/or at different sites during an autoimmune response. We examined the temporal expression of B7 costimulatory molecules in the CNS and in various lymphoid organs during the course of murine relapsing-remitting experimental autoimmune encephalomyelitis (R-EAE). Following immunization of SJL mice with the immunodominant proteolipid protein epitope, PLP139-151, surface expression of B7-1 was up-regulated on B cells, T cells, and macrophages, relative to B7-2, on CNS-infiltrating cells and on splenocytes. Similar enhancement in splenic B7-1 expression could be induced in SJL mice by the adoptive transfer of PLP139-151-specific cells or by immunization with CFA alone. These changes were not observed on lymph node cells, including those isolated from lymph nodes draining the immunization site, which maintained the predominant B7-2 expression pattern seen in naive mice. These phenotypic expression patterns correlated with the functional predominance of B7-1 in costimulating T cell activation when employing APCs from the spleen or CNS of mice with ongoing R-EAE, while B7-2 remained functionally predominant on lymph node APCs. Variation of phenotypic expression and functional dominance of costimulatory molecule expression in different lymphoid compartments during an active inflammatory autoimmune response has important implications in immune regulation, autoimmune pathogenesis, and therapeutic strategies.