Single cell-derived clones from human adipose stem cells present different immunomodulatory properties.

Human adipose mesenchymal stem cells are a heterogeneous population, where cell cultures derived from single-cell-expanded clones present varying degrees of differential plasticity. This work focuses on the immunomodulatory/anti-inflammatory properties of these cells. To this end, five single-cell clones were isolated (generally called 1.X and 3.X) from two volunteers. Regarding the expression level of the lineage-characteristic surface antigens, clones 1·10 and 1·22 expressed the lowest amounts, while clones 3·10 and 3·5 expressed more CD105 than the rest and clone 1·7 expressed higher amounts of CD73 and CD44. Regarding cytokine secretion, all clones were capable of spontaneously releasing high levels of interleukin (IL)-6 and low to moderate levels of IL-8. These differences can be explained in part by the distinct methylation profile exhibited by the clones. Furthermore, and after lipopolysaccharide stimulation, clone 3.X produced the highest amounts of proinflammatory cytokines such as IL-1ß, while clones 1·10 and 1·22 highly expressed IL-4 and IL-5. In co-culture experiments, clones 1.X are, together, more potent inhibitors than clones 3.X for proliferation of total, CD3(+) T, CD4(+) T and CD8(+) T lymphocytes and natural killer (NK) cells. The results of this work indicate that the adipose stem cell population is heterogeneous in cytokine production profile, and that isolation, characterization and selection of the appropriate cell clone is a more exact method for the possible treatment of different patients or pathologies.

[Pulmonary valvular agenesis treated with cryopreserved pulmonary homograft]. / Agenesia valvular pulmonar tratada con homoinjerto pulmonar crioconservado.

We report successful treatment of pulmonary valve agenesia with pulmonary stenosis and ventricular septal defect by infundibular resection, patch-closure of the VSD and implantation of a cryopreserved pulmonary homograft. Cases with mild to moderate hypoplasia of the pulmonary annulus are particularly well suited for direct pulmonary homograft implantation, while cases with severe hypoplasia and high right ventricular pressure after correction may be better treated with aortic homografts. Some technical aspects of homograft implantation (doing first the proximal suture, preserving the normal configuration of the valvular sinuses and using the subvalvular homograft tissue to enlarge the right ventricular outflow tract) may prevent significant valvular incompetence.

[A genetic and hormonal study of 5 patients with the nonclassical form of congenital adrenal hyperplasia due to 21-hydroxylase deficiency]. / Estudio genético y hormonal de 5 pacientes afectados de la forma no clásica de hiperplasia suprarrenal congénita por déficit de 21-hidroxilasa.

BACKGROUND: To study the association between the 21-hydroxylase deficiency with the HLA histocompatibility complex in a mediterranean ethnic group. METHODS: 5 patients with late-onset 21-hydroxylase deficiency, diagnosed on the basis of a high plasma level of 17-hydroxyprogesterone, along with 23 family members were typed. 17-hydroxyprogesterone response to iv ACTH stimulus was measured too in the family members. RESULTS: We found a genetic linkage disequilibrium between the late-onset 21-hydroxylase deficiency and the HLA antigen B51. Moreover, similar biologic profiles were observed in the patients and those of their siblings who were HLA identical. The heterozygous carriers showed a intermediate 17-hydroxyprogesterone response to ACTH between propositus and homozygotes and their family members who had no HLA haplotype identical to those of the propositus. CONCLUSIONS: These observations tend to confirm that a close linkage exits between the gene (or genes) for 21-hydroxylase deficiency in late-onset adrenal hyperplasia and the HLA genes. This association may change in the different ethnic groups.

Human in vivo-induced spontaneous IgG-secreting cells from tonsil, blood and bone marrow exhibit different phenotype and functional level of maturation.

The subset of human spontaneous IgG-secretion cells consists of mature B lymphocytes which are capable of active and high rate IgG production in vitro without the need for additional stimuli. Therefore, such a cell subset provides a useful model for studying the terminal stages of B-cell maturation. The present work analyses the phenotypic and functional characteristics of spontaneous IgG secreting cells obtained from tonsil, blood and bone marrow. The tonsilar cell subset was CD9+ CD20+ CD19+ CD38+/-, the blood cell subset CD9- CD20- CD19+ CD38+/- and bone marrow cells were CD9- CD20- CD19+/- CD38+. The three cell subsets required de novo RNA and protein synthesis for IgG secretion to occur. Tonsilar and blood, but not bone marrow, subsets also required DNA synthesis to undergo IgG secretion. Kinetics studies revealed that IgG production by tonsil and blood cells reached a plateau after 3 days of culture. In contrast, the bone marrow cell subset secreted IgG in a linear fashion for 2 weeks. These results indicate that spontaneous IgG-secreting cells from different organs exhibit functional and phenotypic heterogeneity.

Differential effect of anti-HLA class I monoclonal antibodies on resting and in vivo-induced B lymphocytes.

The role of HLA class I antigens in B cell triggering was investigated by analyzing the effect of monoclonal antibodies (MAbs) directed to such molecules on the in vitro function of resting and in vivo-induced lymphoblastoid (LB) B cells. Staphylococcus aureus Cowan I (SAC)-induced proliferation of high-density B lymphocytes was markedly inhibited by W6/32 MAb (reactive with a monomorphic determinant contributed by an alpha-chain and beta 2-microglobulin) but not by FG2/2 MAb (reactive with beta 2-microglobulin). The inhibition was not due to either a toxic effect or a change in the response kinetics. In contrast, LB B cells' spontaneous DNA synthesis and IgG production was not altered by such MAb, although these cells possessed surface HLA class I antigens. These findings suggest that HLA class I molecules are involved in the activation process of resting but not mature B lymphocytes.

Human B lymphocytes capable of spontaneous Ig production in short-term cultures. II. Relationship with the spontaneous DNA-synthesizing B cells.

It has been previously demonstrated that normal nonimmunized individuals possess circulating and tissular B cells, which are capable of spontaneous immunoglobulin (Ig) production in short-term (3 days) cultures. We have also observed the occurrence of low levels of [3H]thymidine uptake early in such cultures. This work analyzes the relationship between both spontaneous B-cell functions in vitro: Kinetics studies revealed that both activities were temporarily related, as spontaneous DNA synthesis was maximal from 8 to 12 hr, and declined thereafter, when spontaneous Ig secretion was first detected in the culture supernatant: The abrogation of DNA synthesis at the culture initiation or during the period of early proliferation, but not after 24 hr, inhibited subsequent IgG secretion. The B cells responsible for spontaneous DNA synthesis and IgG secretion exhibited similar low densities, since both were recovered in the 42.5-45% Percoll fractions, and identical large size as determined by 1g sedimentation procedure, and in tonsil, were equally reactive with the BA-2 mouse monoclonal antibody. Finally, limiting dilution analysis showed that the precursor frequencies of both cells under study were similar. These results suggest that spontaneous DNA synthesis and IgG production are carried out by the same subset of in vivo-preactivated lymphoblastoid B cells.