Introduction:Coronavirus disease 2019(COVID-19)may be associated with various skin manifestations.Among them,figurate erythema(FE)is rare;only a few clinical reports have been published.Herein,we reported an unusual concentric FE lesions and their immunohistochemical profile in a patient with COVID-19.Case presentation:A 52-year-old woman was diagnosed with COVID-19.One month later,she developed asymptomatic annular erythematous concentric ring lesions on her inner right thigh.The margin of every ring increased in coloration,and the lesions then completely resolved in 2 weeks.A biopsy revealed vasculitis of small vessels,an increase in the fluorescence intensity of CD3 and CD45,and negativity for COVID-19 RNA.Discussion:The results showed an unusual FE that has a clinical mixed type between erythema annulare centrifugum and erythema gyratum repens;the physiopathological mechanism in the FE due to COVID-19 is unknown;one theory involves rapid viral passage into the cutaneous vascular system that triggers an immune and inflammatory response.Although the results exhibited a negative COVID-19 RNA in the tissue,the CD3^(+)/CD45^(+)lymphocyte infiltration could explain the clinical pattern as a direct inflammatory response in the small vessel or as a delayed immune response.Conclusion:Our findings suggest an immunohistochemical small vessel vasculitis pattern with an unusual clinical FE that differs from other types of COVID-19-associated FE or erythema reported previously.
Lucía Achell Achell-NavaJosé Luis Zaldivar-FujigakiRebeca Pérez-Cabeza de VacaAna Maria Espinosa GarcíaLuis Montiel López
目的:应用肌性斜颈兔动物模型,探讨针刀治疗肌性斜颈的作用机制及意义。方法:无水酒精注射制备动物肌性斜颈兔子模型后,选取模型兔子48只,随机分为正常组、模型组、针刀组、按摩组,每组12只。分别给予各组对应治疗,治疗2个月后各组分别取部分胸锁乳突肌制作标本,免疫组化法观察钙蛋白酶1(calpain-1)、分化抗原决定簇45(CD45)、基质金属蛋白酶2(matrix metalloproteinase-2,MMP-2)、基质金属蛋白酶抑制因子2(tissue inhibitor of metalloproteinases-2,TIMP-2)在各组肌纤维中的表达情况。结果:与正常组比较,其余各组实验动物明显出现颈部活动受限、斜颈、头颈不对称症状,而治疗结束后,针刀组和按摩组实验动物颈部活动受限改善,无明显头颈不对称症状。calpain-1、CD45、TIMP-2的表达,与正常组比较,模型组、按摩组上调(P<0.01);与模型组比较,针刀组、按摩组下调(P<0.01);与针刀组比较,按摩组上调(P<0.01)。MMP-2表达,与正常组比较,模型组下调(P<0.01),与模型组比较,针刀组、按摩组上调(P<0.05)。结论:针刀治疗肌性斜颈效果显著,其作用机制可能与减少calpain-1、CD45、TIMP-2表达,增加MMP-2表达有关。
Circulating tumor cells(CTCs)are precursors of distant metastasis in a subset of cancer patients.A better understanding of CTCs heterogeneity and how these CTCs survive during hematogenous dissemination could lay the foundation for therapeutic prevention of cancer metastasis.It remains elusive how CTCs evade immune surveillance and elimination by immune cells.In this study,we unequivocally identified a subpopulation of CTCs shielded with extracellular vesicle(EVs)-derived CD45(termed as CD45^(+)CTCs)that resisted T cell attack.A higher percentage of CD45^(+)CTCs was found to be closely correlated with higher incidence of metastasis and worse prognosis in cancer patients.Moreover,CD45^(+)tumor cells orchestrated an immunosuppressive milieu and CD45^(+)CTCs exhibited remarkably stronger metastatic potential than CD45−CTCs in vivo.Mechanistically,CD45 expressing on tumor surfaces was shown to form intercellular CD45-CD45 homophilic interactions with CD45 on T cells,thereby preventing CD45 exclusion from TCR-pMHC synapse and leading to diminished TCR signaling transduction and suppressed immune response.Together,these results pointed to an underappreciated capability of EVs-derived CD45-dressed CTCs in immune evasion and metastasis,providing a rationale for targeting EVs-derived CD45 internalization by CTCs to prevent cancer metastasis.
