Clinical and radiological features of posterior cortical atrophy (PCA) in a GRN mutation carrier: a case report.

BACKGROUND AND PURPOSE: Posterior cortical atrophy (PCA) is a rare neurodegenerative syndrome, defined by a distinctive clinical-radiological profile, with Alzheimer's disease (AD) pathology accounting for the majority of cases. The aim of this report was to present the case of a patient with impairment of visual and constructional abilities as initial manifestations. METHOD: The patient underwent a multidimensional assessment, including neuropsychological evaluation, structural and functional imaging and genetic screening. RESULTS: Neurological and neuropsychological assessment showed an impairment of constructive and visuo-spatial skills, associated with dyscalculia, simultanagnosia, optic ataxia and oculomotor apraxia. In accordance with the latest consensus criteria, a diagnosis of PCA was made. Consistent with the clinical findings, structural and functional imaging showed a peculiar pattern of atrophy with primary involvement of right parieto-occipital cortices, whereas cerebrospinal fluid biochemical analysis did not reveal a profile compatible with AD pathology. Genetic screening identified a known pathogenic GRN mutation. CONCLUSION: We present a case of PCA in a GRN mutation carrier in whom a concomitant AD pathological process was excluded. Consequently, although lacking histological data, our case suggests GRN-related pathology causative of PCA. Through this report we provide further evidence for a new neurodegenerative pathway leading to PCA, extending the clinical spectrum of GRN-associated phenotypes.

Trends in immune cell function assay and donor-specific HLA antibodies in kidney transplantation: A 3-year prospective study.

The immune cell function assay (ICFA) and de novo anti-donor-specific HLA antibodies (DSA) have been proposed as assays for immune monitoring in renal transplantation, but longitudinal studies examining the modification of both parameters over time and their relation with clinical events are lacking. We prospectively measured longitudinal changes in ICFA and DSA levels in 55 kidney transplant recipients over 3-year follow-up (534 visits) and analyzed their relation with the risk of developing acute rejections or infections. Seven patients (12.7%) developed biopsy-proven acute rejection, and 20 (36.4%) developed viral infections. At 3 years posttransplant, 28% of the patients had developed de novo DSA. ICFA levels peaked at 1-2 months posttransplant (p = 0.005) and leveled off thereafter. They were not associated with the risk of acute rejections, viral infections or development of de novo DSA. Instead, the incidence of de novo DSA was higher in patients who previously had viral infections (adjusted-odds ratio of de novo DSA associated with prior infections: 6.03 [95% CI, 1.64-22.06; p = 0.007]). Our prospective, longitudinal study does not support using ICFA to quantify the immune risk in kidney transplantation. Further studies are needed to confirm the relationship between viral infections and the subsequent development of de novo DSA.

IFN-alpha amplifies human naive B cell TLR-9-mediated activation and Ig production.

TLRs are a family of molecules that function as sensors for the detection of pathogens. TLR-9, expressed on B cells and pDCs, recognizes CpG motifs of unmethylated bacterial DNA and plays a role in the development of autoimmunity. The present study was designed to investigate the effects of IFN-alpha in combination with CpG ODN on the activation of CD27(-) naïve B cells and on Ig production. We provide evidence that CpG ODN not only induces a total and T-dependent, specific IgM response by naïve B cells but also their phenotypic differentiation in plasma cells, as demonstrated by the up-regulation of CD38 expression. We found that TLR-9 stimulation with CpG ODN induces IL-1beta, TNF-alpha, IL-10, and IL-6 production. Interestingly, we also found that CpG ODN induces naïve B cell maturation into memory cells, as demonstrated by the induction of CD27, AID mRNA expression, and IgG production. More importantly, our results demonstrate that IFN-alpha amplifies the inductive effect of CpG ODN on naïve B activation and on Ig production through a mechanism involving TLR-9/MyD88-dependent signaling. Moreover, we found that IFN-alpha enhances the frequency of CpG ODN-induced memory B cells. Our results may contribute to clarify the events promoting IFN-alpha-induced amplification of naïve B cell activation via TLR-9 for a better understanding of the pathogenesis of autoimmune disorders and may guide treatments targeting this pathway within B cells.