Phenotypic characteristics of human type II alveolar epithelial cells suitable for antigen presentation to T lymphocytes.

Type II alveolar epithelial cells (AECII) are well known for their role in the innate immune system. More recently, it was proposed that they could play a role in the antigen presentation to T lymphocytes but contradictory results have been published both concerning their surface expressed molecules and the T lymphocyte responses in mixed lymphocyte cultures. The use of either AECII cell line or fresh cells could explain the observed discrepancies. Thus, this study aimed at defining the most relevant model of accessory antigen presenting cells by carefully comparing the two models for their expression of surface molecules necessary for efficient antigen presentation.

Age-related immune reconstitution during highly active antiretroviral therapy in human immunodeficiency virus type 1-infected children.

OBJECTIVES: To evaluate the immune reconstitution in HIV-1-infected children in whom highly active antiretroviral therapy (HAART) controlled viral replication and to assess the existence of a relation between the magnitude of this restoration and age. METHODS: All HIV-1-infected children in whom a new HAART decreased plasma viral load below 400 copies/ml after 3 months of therapy were prospectively enrolled in a study of their immune reconstitution. Viral load, lymphocyte phenotyping, determination of CD4+ and CD8+ T cell receptor repertoires and proliferative responses to mitogens and recall antigens were assessed every 3 months during 1 year. RESULTS: Nineteen children were evaluated. Naive and memory CD4+ percentages were already significantly increased after 3 months of HAART. In contrast to memory CD4+ percentages, naive CD4+ percentages continued to rise until 12 months. Age at baseline was inversely correlated with the magnitude of the rise in naive CD4+ cells after 3, 6 and 9 months of therapy but not after 12 months. Although memory and activated CD8+ cells were already decreasing after 3 months, abnormalities of the CD8 T cell receptor repertoire and activation of CD8+ cells persisted at 1 year. HAART increased the response to mitogens as early as 3 months after starting therapy. CONCLUSIONS: In children the recovery of naive CD4+ cells occurs more rapidly if treatment is started at a younger age, but after 1 year of viral replication control, patients of all ages have achieved the same level of restoration. Markers of chronic activation in CD8+ cells persist after 1 year of HAART.

Evaluation of HER2, p53, bcl-2, topoisomerase II-alpha, heat shock proteins 27 and 70 in primary breast cancer and metastatic ipsilateral axillary lymph nodes.

BACKGROUND: Breast cancer is a heterogeneous disease. Predictive biological markers (BM) of responsiveness to therapy need to be identified. Evaluation of BM is mainly done at the primary site. However, in the adjuvant therapy of breast cancer, the main goal is control of micrometastases. It is still unknown whether heterogeneity in the expression of BM between the primary site and its micrometastases exists. OBJECTIVE: To evaluate the expression of some BM with potential predictive value from the primary breast cancer site and metastatic ipsilateral axillary lymph nodes. PATIENTS AND METHODS: Focality (percentage of positive cells) and intensity staining scores were evaluated for each marker. Freshly cut sections (4 microm) from embedded blocks of breast cancer fixed in formalin or bouin were put onto superfrost slides (Menzel-Gläser). Protein expression was evaluated immunohistochemically (IHC) using monoclonal antibodies against: topo II-alpha (clone KiS1, 1 microg/ml, Roche) with a trypsine pre-treatment (P); HSP27 (clone G3.1, 1/60, Biogenex), HSP70 (clone BRM.22, 1/80, Biogenex) and HER2 (clone CB11, 1/40, Novocastra; without P); p53 (clone D07, 1/750, Dako) and bcl-2 (clone 124, 1/60, Dako) with citrate buffer as P. RESULTS: Overall, the percentage of discordant marker status in the primary tumour and its metastatic lymph nodes was 2% for HER2, 6% for p53, 15% for bcl-2, 19% for topoisomerase II-alpha, 24% for HSP27 and 30% for HSP70. For the subgroup of patients with positive BM in the primary tumour, the percentage of discordance was 6% for HER2, 7% for p53, 14% for bcl-2, 19% for HSP70, 21% for topoisomerase II-alpha and 36% for HSP27. For the subgroup of patients with positive BM in the lymph nodes, the percentage of discordance was 9% for bcl-2, 15% for HER2 and p53, 21% for topoisomerase II-alpha, 22% for HSP27 and 25% for HSP70. CONCLUSIONS: 1) No biological marker had 100% concordant results. 2) Although some discordant cases might be explained by the limitations of the IHC technique, future studies aiming to evaluate the predictive value of BM in the adjuvant therapy of breast cancer should take into account a possible difference in BM expression between the primary and the metastatic sites.

Revisiting human IL-12Rβ1 deficiency: A survey of 141 patients from 30 countries

Interleukin-12 receptor β1 (IL-12Rβ1) deficiency is the most common form of Mendelian susceptibility to mycobacterial disease (MSMD). We undertook an international survey of 141 patients from 102 kindreds in 30 countries. Among 102 probands, the first infection occurred at a mean age of 2.4 years. In 78 patients, this infection was caused by Bacille Calmette-Guérin (BCG; n = 65), environmental mycobacteria (EM; also known as atypical or nontuberculous mycobacteria) (n = 9) or Mycobacterium tuberculosis (n = 4). Twenty-two of the remaining 24 probands initially presented with nontyphoidal, extraintestinal salmonellosis. Twenty of the 29 genetically affected sibs displayed clinical signs (69%); however 8 remained asymptomatic (27%). Nine nongenotyped sibs with symptoms died. Recurrent BCG infection was diagnosed in 15 cases, recurrent EM in 3 cases, recurrent salmonellosis in 22 patients. Ninety of the 132 symptomatic patients had infections with a single microorganism. Multiple infections were diagnosed in 40 cases, with combined mycobacteriosis and salmonellosis in 36 individuals. BCG disease strongly protected against subsequent EM disease (p = 0.00008). Various other infectious diseases occurred, albeit each rarely, yet candidiasis was reported in 33 of the patients (23%). Ninety-nine patients (70%) survived, with a mean age at last follow-up visit of 12.7 years ± 9.8 years (range, 0.5-46.4 yr). IL-12Rβ1 deficiency is characterized by childhood-onset mycobacteriosis and salmonellosis, rare recurrences of mycobacterial disease, and more frequent recurrence of salmonellosis. The condition has higher clinical penetrance, broader susceptibility to infections, and less favorable outcome than previously thought. © 2010 Lippincott Williams & Wilkins.

Androgenic 17β-hydroxysteroid dehydrogenase activity of expressed rat type I 3β-hydroxysteroid dehydrogenase/Δ5-Δ4 isomerase

Transient expression in nonsteroidogenic mammalian cells of the rat wild type I and type II 3β-hydroxysteroid dehydrogenase/Δ5-Δ4-isomerase (3β- HSD) cDNAs shows that the encoded proteins, in addition to being able to catalyze the oxidation and isomerization of Δ5-3β-hydroxysteroid precursors into the corresponding Δ4-3-ketosteroids, interconvert 5α- dihydrotestosterone (DHT) and 5α-androstane-3β,17β-diol (3β-diol). When homogenate from cells transfected with a plasmid vector containing type I 3β-HSD is incubated in the presence of DHT using NAD+ as cofactor, a somewhat unexpected metabolite is formed, namely 5α-androstanedione (A- dione), thus indicating an intrinsic androgenic 17β-hydroxysteroid dehydrogenase (17β-HSD) activity of this 3β-HSD isoform. Although the relative Vmax of 17β-HSD activity is 14.9-fold lower than that of 3β-HSD activity, the Km value for the 17β-HSD activity of type I 3β-HSD is 7.97 μM, a value which is in the same range as the conversion of DHT into 3β- diol which shows a Km value of 4.02 μM. Interestingly, this 17β-HSD activity is highly predominant in unbroken cells in culture, thus supporting the physiological relevance of this 'secondary' activity. Such 17β-HSD activity is inhibited by the classical substrates of 3β-HSD, namely pregnenolone (PREG), dehydroepiandrosterone (DHEA), Δ5-androstene-3β,17β- diol (Δ5-diol), 5α-androstane-3β,17β-diol (3β-diol) and DHT, with IC50 values of 2.7, 1.0, 3.2, 6.2, and 6.3 μM, respectively. Although dual enzymatic activities have been previously reported for purified preparations of other steroidogenic enzymes, the present data demonstrate the multifunctional enzymatic activities associated with a recombinant oxidoreductase enzyme. In addition to its well known 3β-HSD activity, this enzyme possesses the ability to catalyze DHT into A-dione thus potentially controlling the level of the active androgen DHT in classical steroidogenic as well as peripheral intracrine tissues.