The expression of paired immunoglobulin-like receptor B (PirB) in normal and injured spinal cord of rats was investigated. The SD rat hemi-sectioned spinal cord injury (SCI) model was established. Before and 1, 3, 7, 10 days after SCI, the spinal cord tissues were harvested, and Western blot and immunohistochemistry were used to examine the expression and location of PirB. The results showed that the expression level of PirB in the normal spinal cord of SD rats was low. At the first day after SCI, the expression of PirB was obviously increased, and that in the injured spinal cord from the first day to the 10th day was significantly higher than in the normal spinal cord. The positive expression of PirB in neurons from different regions of gray matter of the injured spinal cord was seen. It was concluded that the expression of PirB in the normal spinal cord of rats was low. The expression of PirB in SCI was significantly increased till at least the 10th day.

The expression of paired immunoglobulin-like receptor B(PirB)in normal and injured spinal cord of rats was investigated.The SD rat hemi-sectioned spinal cord injury(SCI)model was established.Before and 1,3,7,10 days after SCI,the spinal cord tissues were harvested,and Western blot and immunohistochemistry were used to examine the expression and location of PirB.The results showed that the expression level of PirB in the normal spinal cord of SD rats was low.At the first day after SCI,the expression of PirB was obviously increased,and that in the injured spinal cord from the first day to the 10th day was significantly higher than in the normal spinal cord.The positive expression of PirB in neurons from different regions of gray matter of the injured spinal cord was seen.It was concluded that the expression of PirB in the normal spinal cord of rats was low.The expression of PirB in SCI was significantly increased till at least the 10th day.

Objective:To study the pathological changes of the spleen in patients with COVID-19 and to analyze the relationship between the weakened immune system and splenic lesions.Methods:Postmortem needle autopsies from the spleen were carried out on 10 patients who died from COVID-19 in Wuhan. Routine hematoxylin and eosin (HE) staining was used to observe the pathological changes. The changes of lymphocytes were studied further with immunohistochemistry.RT-PCR was used to detect 2019-nCoV RNA in the spleen. In addition,the Epstein-Barr virus (EBV) was detected by in situ hybridization, and coronavirus particles were detected by transmission electron microscopy in 2 cases.Results:There were 7 males and 3 females, with an average age of 68.3 years.Of the 10 cases, 4 had cancer history and another 4 had other underlying diseases respectively.Cough, fever, malaise and dyspnea were the main clinical symptoms.The time from onset to death was 15-45 days.Ten cases patients had normal or slight increase in peripheral blood leukocyte count in the early stage of the disease, 6 cases had significant increase before death. Five patients′ peripheral blood lymphocyte count decreased in the early stage of the disease, and 10 patients′ peripheral blood lymphocyte count decreased significantly before the disease progressed or died. Seven cases were treated with corticosteroid (methylprednisolone ≤40?mg/d, not more than 5 days). Histopathological examination showed that the cell composition of the spleen decreased, white pulp atrophied at different levels, meanwhile lymphoid follicles decreased or absent;in addition, the ratio of red pulp to white pulp increased with varying degrees. In 7 cases, more neutrophil infiltration was found, and in 5 cases, scattered plasma cell infiltration was found. Macrophage proliferation and hemophagocytic phenomena in a few cells were found in a case. Meanwhile, necrosis and lymphocyte apoptosis were detected in 2 cases, small artery thrombosis and spleen infarction in 1 case, and fungal infection in 1 case. The results of immunohistochemistry showed that the T and B lymphocyte components of the spleen in all cases decreased in varying degrees. CD20 + B cells were found to accumulate in the lymphoid sheath around the splenic artery in 8 cases. However, CD20 and CD21 immunostaining in 2 cases showed that the number of white pulp was almost normal, and splenic nodules were atrophic. CD3 +, CD4 + and CD8 +T cells were decreased. In 9 cases,CD68 + macrophages were no significant changes in the distribution and quantity. While more CD68 + cells were found in the medullary sinuses of 1 case (related to fungal infection). Few CD56 + cells were found. EBV was negative by in situ hybridization. RT-PCR was used to detect the nucleic acid of 2019-nCoV. One of 10 cases was positive, 39 years old,who was the youngest patient in this group, and the other 9 cases were negative. Coronavirus particles were found in the cytoplasm of macrophage under electron microscope in 2 cases. Conclusions:The death of COVID-19 occurs mainly in the elderly, and some cases have no underlying diseases. Spleen may be one of the organs directly attacked by the virus in some patients who died from COVID-19. T and B lymphocyte in the spleen decrease in varying degrees, lymphoid follicles are atrophied, decreased or absent, and the number of NK cells do not change significantly. And the pathological changes of the spleen are not related to the use of low dose corticosteroid, which may be related to the direct attack of virus and the attack of immune system on its own tissues.

Purpose To investigate the clinicopathologic,immunophenotypic features,genetic alterations and prognosis of melanotic Xp11 neoplasms/melanotic TFE3-rearrangement neo-plasms.Methods Five cases were selected from the Depart-ment of Pathology,Union Hospital,Huazhong University of Sci-ence and Technology from November 2018 to July 2023.The clinicopathologic,immunohistochemical,FISH assays,next-generation sequencing(NGS)and follow-up details were collect-ed.Results There were 1 male and 4 females,with their ages ranging from 16 to 59 years(mean 28.2 years).The maximum diameters of the masses were 3-6 cm(average 4.7 cm).The tumors located in right kidneys(3 cases),tubal interstitium(1 case)and pelvis(1 case).Microscopically,most tumors shared similar morphology such as nested,acinar structures sep-arated by a delicate vascular network.Epithelioid tumor cells presented with clear to granular eosinophilic cytoplasm.Lym-phocytic infiltration was seen in the background;melanin depo-sition was noted in the cases;neoplastic necrosis was detected in 4 cases.Mitotic activity was low with 5 cases showing＜3/10 HPF.Intravascular tumor thrombus was detected in 2 cases,no lymphovascular and nerve invasions were detected in other 3 ca-ses.Immunohistochemically,all 5 cases expressed TFE3 dif-fusely,and expressed HMB45,Melan A to varying degrees,CK(AE1/AE3),CK7,EMA,PAX8,TFEB,S-100,SOX10,SMA,desmin were all non-reactive in the 5 cases.The Ki67-la-beling index was＜20％.TFE3 separation signal in 4 cases were detected by FISH,1 case was interpreted as negative due to atypical signal which was confirmed by next-generation se-quencing(NGS)assay as RBM10-TFE3.Clinical follow-up was available for five patients for 2-60 months,in which four pa-tients were alive with no evidence of disease after initial resec-tion,and one patient with thoracic spine metastasis was currently in stable condition.Conclusion Melanotic Xp1 1 neoplasms/melanotic TFE3-rearrangement neoplasms has unique morpholog-ic,immunophenotypic and genetic characteristics.It might be reclassified into a distinctive malignant mesenchymal tumor enti-ty.

Humans ; Proto-Oncogene Proteins p21(ras)/genetics* ; Prognosis ; Biomarkers, Tumor/genetics* ; Mutation/genetics* ; Colorectal Neoplasms/genetics* ; Proto-Oncogene Proteins B-raf/metabolism*