Follicular CD8+ T cells promote immunoglobulin production and demyelination in multiple sclerosis and a murine model.

Emerging evidence underscores the importance of CD8+ T cells in the pathogenesis of multiple sclerosis (MS), but the precise mechanisms remain ambiguous. This study intends to elucidate the involvement of a novel subset of follicular CD8+ T cells (CD8+CXCR5+ T) in MS and an experimental autoimmune encephalomyelitis (EAE) murine model. The expansion of CD8+CXCR5+ T cells was observed in both MS patients and EAE mice during the acute phase. In relapsing MS patients, higher frequencies of circulating CD8+CXCR5+ T cells were positively correlated with new gadolinium-enhancement lesions in the central nervous system (CNS). In EAE mice, frequencies of CD8+CXCR5+ T cells were also positively correlated with clinical scores. These cells were found to infiltrate into ectopic lymphoid-like structures in the spinal cords during the peak of the disease. Furthermore, CD8+CXCR5+ T cells, exhibiting high expression levels of ICOS, CD40L, IL-21, and IL-6, were shown to facilitate B cell activation and differentiation through a synergistic interaction between CD40L and IL-21. Transferring CD8+CXCR5+ T cells into naïve mice confirmed their ability to enhance the production of anti-MOG35-55 antibodies and contribute to the disease progression. Consequently, CD8+CXCR5+ T cells may play a role in CNS demyelination through heightening humoral immune responses.

Lysinibacillus agricola sp. nov., isolated from soil.

A gram-staining-positive, rod-shaped bacterium, designed strain FJAT-51161T was isolated from farmland soil collected from Fujian Province, China. Growth was observed at 25-40 °C (optimum 30 °C), pH 7.0-9.0 (optimum 7.0), and NaCl tolerance in the range of 0-7% (w/v), respectively. Phylogenetic analysis based on the 16S rRNA gene sequences indicated that the strain FJAT-51161T belonged to the genus Lysinibacillus, and had the closest relationship with Lysinibacillus xylanilyticus XDB9T (99.0% 16S rRNA sequence similarity). The digital DNA-DNA hybridization (dDDH) and average nucleotide identity (ANI) values based on the genome sequence analysis between strain FJAT-51161T and the closest reference strain were 38.0% for dDDH and 88.7% for ANI, respectively, lower than the prokaryotic species delineation values. Further analysis showed that strain FJAT-51161T shared the fatty acid profiles such as iso-C15:0 (46.7%), iso-C16:0 (15.8%), C16:1 ω7c alcohol (14.0%), anteiso-C15:0 (6.9%) with other members of the genus Lysinibacillus. As the peptidoglycan contained the amino acids alanine, lysine, glycine and aspartic acid, the type A4α was deduced as found in the closest relatives of strain FJAT-51161T. The peptidoglycan of strain FJAT-51161T was L-Lys-D-Asp (type A4α). The main quinone was MK-7 and MK-6. The major polar lipids were diphosphatidylglycerol (DPG) and phosphatidylethanolamine (PE). The DNA G + C content is 36.6 mol%. Based on the phenotypic characters and taxono-genomics study, strain FJAT-51161T is considered to represent a novel Lysinibacillus species, for which the name Lysinibacillus agricola sp. nov. is proposed. The type strain is FJAT-51161T (GDMCC1.2350T = KCTC 43326T).

Intracranial lesion as onset symptom in a patient with early undifferentiated connective tissue disease: a case report.

BACKGROUND: Undifferentiated connective tissue disease (UCTD) is widely considered to be a distinct clinical entity, and now divided into two subgroups: stable UCTD and early UCTD. The most frequent onset symptoms of UCTD include arthralgias, arthritis, Raynaud's phenomenon, mucocutaneous involvement, and sicca symptoms. However, Neurologic involvement is rare, and intracranial lesion as onset symptom in a patient with early UCTD has not yet been reported. CASE PRESENTATION: A 51-year-old Chinese female experienced progressive left leg weakness for 14 days before hospitalizing in our department. The lesion on right parietal lobe was initially detected by brain magnetic resonance imaging. Although the patient declined a cerebral biopsy, the possibility of stroke, cerebral venous sinus thrombosis, NMOSD, MS, autoimmune encephalitis, intracranial infections, and malignant tumors as cause of the lesion was excluded by intracranial angiogram, CSF study, MRI enhancement and MRS examination. Moreover, immunologic studies showed high titer of antinuclear antibody, increased erythrocyte sedimentation rate and C-reactive protein. These results led to a diagnosis of early UCTD with central nerve system (CNS) involvement. After low dose corticosteroid and azathioprine therapy, the patient's symptoms, abnormalities in immunologic tests and cerebral radiologic examinations were all greatly improved within a short duration. CONCLUSIONS: This is the first report of intracranial lesion as onset symptom in a patient with early UCTD. Our case suggested that central nerve system (CNS) involvement could be the onset symptom in early UCTD, and should be recognized quickly with exclusion of other causative factors in the differential diagnosis. Prompt and adequate treatment with low-dose steroid and immunosuppressive drugs could improve the prognosis of both early UCTD and CNS involvement.