Coordinated expansion of memory T follicular helper and B cells mediates spontaneous clearance of HCV reinfection.

Introduction: Follicular helper T cells are essential for helping in the maturation of B cells and the production of neutralizing antibodies (NAbs) during primary viral infections. However, their role during recall responses is unclear. Here, we used hepatitis C virus (HCV) reinfection in humans as a model to study the recall collaborative interaction between circulating CD4 T follicular helper cells (cTfh) and memory B cells (MBCs) leading to the generation of NAbs. Methods: We evaluated this interaction longitudinally in subjects who have spontaneously resolved primary HCV infection during a subsequent reinfection episode that resulted in either another spontaneous resolution (SR/SR, n = 14) or chronic infection (SR/CI, n = 8). Results: Both groups exhibited virus-specific memory T cells that expanded upon reinfection. However, early expansion of activated cTfh (CD4+CXCR5+PD-1+ICOS+FoxP3-) occurred in SR/SR only. The frequency of activated cTfh negatively correlated with time post-infection. Concomitantly, NAbs and HCV-specific MBCs (CD19+CD27+IgM-E2-Tet+) peaked during the early acute phase in SR/SR but not in SR/CI. Finally, the frequency of the activated cTfh1 (CXCR3+CCR6-) subset correlated with the neutralization breadth and potency of NAbs. Conclusion: These results underscore a key role for early activation of cTfh1 cells in helping antigen-specific B cells to produce NAbs that mediate the clearance of HCV reinfection.

Apicectomía de Primer Molar Inferior. Revisión de Literatura y Reporte de Caso

La apicectomía consiste en la amputación de la fracción apical de la raíz de un diente lesionado y se considera la última opción terapéutica para mantener el diente afectado en boca. Con el objetivo de dilucidar el potencial terapéutico de la técnica quirúrgica, en el presente estudio presentamos el reporte de caso de un paciente con cuadro de hiperestesia asociada al nervio alveolar inferior debido a sobreobturación de la raíz mesial de un primer molar inferior izquierdo. Para resolver el caso realizamos apicectomía mediante abordaje convencional acompañado de medicación empírica enfocada a resolver cuadros de parestesia asociada al procedimiento. Durante los controles posteriores al procedimiento quirúrgico se pesquisa ausencia de parestesia y sintomatología dolorosa, por lo que consideramos la apicectomía como una buena opción de tratamiento en casos de sobreobturación apical que no pueden solucionarse mediante tratamiento no quirúrgico.

Apicoectomy consists of the amputation of the apical fraction of the root of an injured tooth and is considered the last therapeutic option to keep the affected tooth in the mouth. With the aim of elucidating the therapeutic potential of the surgical technique, in this study we present the case report of a patient with hyperesthesia associated with the inferior alveolar nerve due to overfilling of the mesial root of a left lower first molar. To solve the case we performed apicoectomy by conventional approach accompanied by empirical medication focused on resolving paresthesia associated to the procedure. During the controls after the surgical procedure we found absence of paresthesia and painful symptomatology, so we consider apicoectomy as a good treatment option in cases of apical overfilling that cannot be solved by non-surgical treatment.