Author Correction: Diversity of gut microflora is required for the generation of B cell with regulatory properties in a skin graft model.

An amendment to this paper has been published and can be accessed via a link at the top of the paper.

Galectin-1 is required for the regulatory function of B cells.

Galectin-1 (Gal-1) is required for the development of B cells in the bone marrow (BM), however very little is known about the contribution of Gal-1 to the development of B cell regulatory function. Here, we report an important role for Gal-1 in the induction of B cells regulatory function. Mice deficient of Gal-1 (Gal-1-/-) showed significant loss of Transitional-2 (T2) B cells, previously reported to include IL-10+ regulatory B cells. Gal-1-/- B cells stimulated in vitro via CD40 molecules have impaired IL-10 and Tim-1 expression, the latter reported to be required for IL-10 production in regulatory B cells, and increased TNF-α expression compared to wild type (WT) B cells. Unlike their WT counterparts, T2 and T1 Gal-1-/- B cells did not suppress TNF-α expression by CD4+ T cells activated in vitro with allogenic DCs (allo-DCs), nor were they suppressive in vivo, being unable to delay MHC-class I mismatched skin allograft rejection following adoptive transfer. Moreover, T cells stimulated with allo-DCs show an increase in their survival when co-cultured with Gal-1-/- T2 and MZ B cells compared to WT T2 and MZ B cells. Collectively, these data suggest that Gal-1 contributes to the induction of B cells regulatory function.

Diversity of gut microflora is required for the generation of B cell with regulatory properties in a skin graft model.

B cells have been reported to promote graft rejection through alloantibody production. However, there is growing evidence that B cells can contribute to the maintenance of tolerance. Here, we used a mouse model of MHC-class I mismatched skin transplantation to investigate the contribution of B cells to graft survival. We demonstrate that adoptive transfer of B cells prolongs skin graft survival but only when the B cells were isolated from mice housed in low sterility "conventional" (CV) facilities and not from mice housed in pathogen free facilities (SPF). However, prolongation of skin graft survival was lost when B cells were isolated from IL-10 deficient mice housed in CV facilities. The suppressive function of B cells isolated from mice housed in CV facilities correlated with an anti-inflammatory environment and with the presence of a different gut microflora compared to mice maintained in SPF facilities. Treatment of mice in the CV facility with antibiotics abrogated the regulatory capacity of B cells. Finally, we identified transitional B cells isolated from CV facilities as possessing the regulatory function. These findings demonstrate that B cells, and in particular transitional B cells, can promote prolongation of graft survival, a function dependent on licensing by gut microflora.

Mast cell protease 6 is required for allograft tolerance.

It has been shown that mast cells (MC) are absolutely required for transplant acceptance. However, only a few of the numerous mediators produced by MC have been proposed as potential mechanisms for the observed immunosuppression. The role of proteases in acquired immune tolerance as such has not yet been addressed. In this study, we have shown the requirement for MC protease 6 (MCP6), an MC-specific tryptase, to establish tolerance toward an allogeneic skin graft. The substrate for MCP6 is interleukin (IL)-6, cytokine generally considered to indicate transplant rejection. Herein we have shown an inverse correlation between MCP6 and IL-6. High expression of MCP6 is accompanied by low levels of IL-6 when the allograft is accepted, whereas low expression of MCP6 in combination with high levels of IL-6 are observed in rejecting grafts. Moreover, tolerance toward an allogeneic graft cannot be induced in MCP6(-/-) mice. Rejection observed in these mice was comparable to that of MC-deficient hosts; it is T-cell mediated. These findings suggest that MCP6 actively depletes the local environment of IL-6 to maintain tolerance.

Mast cell degranulation breaks peripheral tolerance.

Mast cells (MC) have been shown to mediate regulatory T-cell (T(reg))-dependent, peripheral allograft tolerance in both skin and cardiac transplants. Furthermore, T(reg) have been implicated in mitigating IgE-mediated MC degranulation, establishing a dynamic, reciprocal relationship between MC and T(reg) in controlling inflammation. In an allograft tolerance model, it is now shown that intragraft or systemic MC degranulation results in the transient loss of T(reg) suppressor activities with the acute, T-cell dependent rejection of established, tolerant allografts. Upon degranulation, MC mediators can be found in the skin, T(reg) rapidly leave the graft, MC accumulate in the regional lymph node and the T(reg) are impaired in the expression of suppressor molecules. Such a dramatic reversal of T(reg) function and tissue distribution by MC degranulation underscores how allergy may causes the transient breakdown of peripheral tolerance and episodes of acute T-cell inflammation.

Insuficiencia respiratoria en neumonía por varicela zoster durante el embarazo / Respiratory failure in pneumonia by varicella zoster virus during pregnancy

La infección primaria por VZ en el embarazo es raro, con una incidencia de 1-7/10.000. La neumonía por VZ es una complicación aún más infrecuente, responsable de importante morbimortalidad maternofetal, y cuando se asocia a insuficiencia respiratoria (IR) puede llegar a un 40 por ciento. Se presenta y discute el manejo de una paciente con neumonía por VZ en el primer trimestre de embarazo, complicada con IR, que necesitó apoyo de Ventilación mecánica (VM). Evolucionó a un embarazo de término sin complicaciones fetales ni maternas

[Von Recklinghausen's disease (neurofibromatosis) and pregnancy: apropos of a clinical case]. / Enfermedad de Von Recklinghausen (neurofibromatosis) y embarazo: a propósito de un caso clínico.

We present a case of von Recklinghausen's disease in a patient whose pregnancy resulted in a stillbirth in the third trimester, probably due to placental insuficiency. Although neurofibromatosis is one off the most frequently occurring genetic diseases, its diagnosis is rarely made.

Trauma penetrante torácico: resultados de una conducta terapéutica selectiva / Thoracic penetrating trauma: results of a selective therapeutic behavior

Se estudiaron 33 traumatismos penetrantes torácicos (TPT), tratados en 1982 y 1987. Nuestra conducta consistió en explorar selectivamente el tórax de estos enfermos, basándonos en criterios de gravedad clínicos y radiológicos. La corrección precoz de los trastornos cardiorrespiratorios de ingreso en el TPT, mejora su pronóstico. Los criterios de gravedad estudiados demostraron poseer una confiabilidad suficiente para diagnosticar las lesiones torácicas e indicar selectivamente la toracotomía de urgencia. Los tratamientos médicos y expectante han demostrado ser adecuados para resolver la mayoría de los TPT. La toracotomía nos permitió recuperar a los pacientes más críticos, y además resolver a aquellos cuyo tratamiento expectante había fracasado. Demostramos la utilidad de una conducta terapéutica normada en el TPT aplicable en un hospital de baja complejidad

Squamous cell carcinoma associated with amoebic cervicitis. Report of a case.

A case of squamous cell carcinoma associated with amebiasis is presented. Protozoa identified as Entamoeba histolytica were found in a routine Papanicolaou smear and in the cervical biopsy of a young woman following the initial diagnosis of cervical cancer and the institution of a radiation therapy regimen. No amoebae were found in repeated stool specimens. The late detection and diagnosis of amebiasis precluded any possible changes in the management of the case. Initial follow-up for the carcinoma demonstrated that the patient was not responding well to therapy; her failure to return to the clinic precluded long-term follow-up and treatment for the amebiasis.