T-lymphocyte homeostasis and function in infant baboons: implications for transplantation.

Laboratory mice are born lymphopenic and demonstrate lymphopenia-induced proliferation that generates memory T cells, yet they are prone to immunologic tolerance. Here we tested whether these fundamental immunologic observations apply to higher animals by studying the immune system of infant baboons. Using flow cytometry of the peripheral blood cells, it was found that baboons are born relatively lymphopenic and subsequently expand their initially naïve T cell pool with increasing numbers of memory T cells. After transplantation of an artery patch allograft or xenograft, non-immunosuppressed recipients readily mounted an immune response against donor-type antigens, as evidenced by mixed lymphocyte reaction. Immunosuppression with anti-thymocyte globulin (ATG), anti-CD154 mAb, and mycophenolate mofetil prevented T cell-mediated rejection. After lymphocyte depletion with ATG, homeostatic T cell proliferation was observed. In conclusion, the baboon proved a suitable model to investigate the infant immune system. In this study, neonatal lymphopenia and expansion of the memory T cell population were observed but, unlike mice, there were no indications that infant baboons are prone to T cell tolerance. The expansion of memory T cells during the neonatal period or after induction therapy may actually form an obstacle to tapering immunosuppressive therapy, or ultimately achieving immunologic tolerance.

Novel mutation in ABBC9 gene associated with congenital hypertrichosis and acromegaloid facial features, without cardiac or skeletal anomalies: a new phenotype.

INTRODUCTION: Mutations in ABCC9 are associated with Cantú syndrome (CS), a very rare genetic disorder characterized by congenital hypertrichosis, acromegaloid facial appearance (AFA), cardiomegaly, and skeletal anomalies. CASE REPORT: We report an 8-year-old female patient with congenital generalized hypertrichosis and coarse facial appearance but without cardiovascular or skeletal compromise. Whole exome sequencing revealed a novel de novo heterozygous mutation in ABCC9. In addition, the genotype and phenotype of the patient were compared with those of the patients reported in the literature and with other related conditions that include AFA, hypertrichosis and AFA, and CS. CONCLUSION: This is the first report of a South-American patient with mutation in ABCC9. We propose that her phenotype is a part of a spectrum of features associated with congenital hypertrichosis and mutations in ABCC9, which differs from CS and related disorders. Whole exome sequencing enabled the identification of the causality of this disease characterized by high clinical and genetic heterogeneity.

[Bullous systemic lupus mimicking a Stevens-Johnson syndrome]. / Lupus ampolloso que simula síndrome de Stevens-Johnson.

Autoimmune bullous diseases represent a diagnostic challenge due to the wide spectrum of pathologies that share similar clinical features. This paper reports the case of a woman admitted with a supposed diagnosis of a Stevens-Johnson syndrome, in which the history, the profile of autoimmunity and interdisciplinary approach were of vital importance to clarify the clinical picture.

Las enfermedades ampollosas autoinmunitarias constituyen, en algunas ocasiones, un reto diagnóstico debido al amplio espectro de afecciones que comparten características clínicas similares. Se comunica el caso de una paciente que ingresó con un supuesto diagnóstico de reacción medicamentosa severa tipo síndrome de Stevens-Johnson, en la que sus antecedentes personales, perfil de autoinmunidad y aproximación interdisciplinaria fueron de vital ayuda para establecer el diagnóstico final.