Stimulation and proliferation of CD4+ peripheral blood T lymphocytes induced by an anti-CD4 monoclonal antibody

There is experimental evidence that the CD4 molecule participates in the antigen-driven activation of T cells expressing this surface glycoprotein. Whether CD4, a member of the immunoglobulin supergene family, acts as a ligand-binding molecule and/or is directly involved in the activation pathway has yet to be established. In this study, we show that human CD4⁺ lymphocytes can be activated by exposure to the anti-CD4 monoclonal antibody (mAb) B66. Normal peripheral blood CD4⁺ cells were induced to proliferate and to synthesize interleukin 2 (IL2) by the antibody. The specificity of the antibody stimulatory activity was tested by using IL2-producing clones bearing either CD4 or CD8 on their surface. IL2 production was induced by mAb B66 in CD4+, but not CD8⁺, clones, whereas both types of clones responded to stimulation by the anti-CD3 mAb Leu-4. Despite its unique stimulatory activity, mAb B66 shared with other anti-CD4 antibodies the ability to inhibit the specific cytolytic activity of CD4⁺ effector cells. These results clearly indicate that cross-linking of surface CD4 molecules with appropriate antibodies can fully activate CD4⁺ lymphocytes. Whether the natural ligand for CD4 can trigger this activation pathway remains to be defined.     

Neutropenia induced by platelet-activating factor (PAF-acether) released from neutrophils: The inhibitory effect of prostacyclin (PGI2)

Soluble and phagocytic stimuli released PAF-acether from PMN leucocytes, as determined by chromatography and bioassay by platelet aggregation. The same material caused aggregation of human and rabbit PMN leucocytesin vitro which was inhibited by ETYA and PGI₂. PGI₂ also inhibited PAF-acether release by PMN leucocytes and,in vivo, PGI₂ abolished not only PAF-acether-induced, but also immune complex or C5a-induced thrombocytopenia and neutropenia in rabbits. These data suggest that PAF-acether may be involved in activation of both platelets and PMN leucocytesin vivo.     

Tuberculosis infection and disease in immigrant children

From the second half of the eighties, the cases of tuberculosis (TBC) in Italy have been constantly increasing. The increase in TBC cases in developed countries is related to different factors, including HIV epidemic and increased number of immigrants from countries with high TBC incidence and important socio-economic problems. Compared with adults few children with TBC were homeless or coinfected with HIV, nonetheless the children lived frequently in low socioeconomic status and consequently high risk of being uninsured and with adults at risk for tuberculosis (immediate relative, household members, or recently immigrated). An epidemiologic study was carried out, in order to evaluate the impact of TBC infection in immigrant children. From January 2001 to December 2002, Mantoux test (5 IU) was performed in immigrant children hospitalized or followed in two children hospitals. They included 228 children: mean age 4 years (range 1 month to 15 years). The patients came from: South America (44%) (especially from Ecuador), from Africa (20%), from Eastern Europe (19%), (especially from Middle East and North Africa), from Far East (17%). In 30 cases (13,2%) Mantoux test was positive. Among these latter, 21 presented latent infection, whereas another 9 had tuberculous disease with pulmonary localization and one of them associated with cervical adenopathy. In the study period, among all children (4426) admitted the two Units, the prevalence of tuberculous disease was 2,5% in immigrant children compared 0.2% in native children. Accurate epidemiologic monitoring, further clinical studies aimed at highlighting TBC peculiar aspects in children, and adequate therapy can lead to TBC control in the immigrant children.     

Good Safety Profile and Efficacy of Leucocyte Interferon-α in Combination with Oral Ribavirin in Treatment-Naive Patients with Chronic Hepatitis C

Background: The differential tolerability profile of various interferon (IFN)-α preparations used in combination with ribavirin for the treatment of chronic hepatitis C needs to be elucidated. Approximately 8% of patients receiving recombinant IFNα-2b plus ribavirin discontinue treatment because of adverse events. Human leucocyte IFNα is deemed to have a better safety profile than recombinant IFNα. We therefore compared the safety profile and efficacy of ribavirin combined with leucocyte IFNα or with recombinant IFNα-2b in treatment-naive patients with chronic hepatitis C. Study design: We randomised 423 patients to either leucocyte IFNα 3MU three times weekly plus ribavirin (210 patients) or the same dose of recombinant IFNα-2b plus ribavirin (213 patients). Patients were treated for 24 weeks and followed-up for a further 48 weeks. The primary endpoint was the safety profile of the two therapies; the secondary endpoint was the rate of sustained response. Results: In patients receiving leucocyte IFNα, the total number of adverse events was lower than in the group receiving recombinant IFNα (259 vs 441 patients), and the percentage of patients discontinuing treatment because of adverse events or laboratory abnormalities was significantly reduced (4% vs 11%; p = 0.013). Sustained response was observed in 47% of patients receiving leucocyte IFNα plus ribavirin and in 44% of patients receiving IFNα-2b plus ribavirin. Conclusions: Both therapeutic regimens were effective in inducing a sustained response in naive patients. However, the safety profile of leucocyte IFNα plus ribavirin was more favourable than that observed with the administration of recombinant IFNα-2b plus ribavirin, suggesting that leucocyte IFNα may be an alternative option in patients with reduced tolerability to other IFNs.     

Early (Stage A) prostatic cancer

Summary This study was performed in order to elucidate some of the problems of incidence, morphology and natural history concerned with Stage A prostatic cancer or prostatic microcarcinoma (PMC).The prostates of 100 patients, treated by subtotal prostatectomy for benign prostatic hyperplasia (BPH), were studied by comparing both routine and step-section techniques. The incidence of PMC was 41% by the former and 86% by the latter technique. Assessment of the size of PMC, as measured by the sum of the two main diameters, resulted in three groups: A₁, A₂, A₃. The last of these may represent a frankly malignant condition, judged by size and the histological appearance. Radical prostatectomy is strongly suggested as appropriate therapy for this group.Supported in part by a Grant from the Ministry of Education (art. 286 T.U., 1977/78)     

Effects of HDL3 on the expression of matrix-degrading proteases in human endothelial cells

Modified lipoproteins have been suggested to modulate the expression of matrix-degrading proteases in the vascular wall. Since oxidized high density lipoprotein (HDL) has been found in atheromatous plaques and receptors for modified HDL are present on endothelial cells, we investigated the role of native and oxidized HDL3 on the expression of 35 proteases and their inhibitors in human endothelial cells using microarray analysis. Matrix metalloproteinase (MMP)-1, -2, -10, -13 and -14, tissue inhibitor of MMP (TIMP)-1, -2 and -3, cathepsin B and D, and cystatin C were expressed under basal conditions, of which MMP-10 and cystatin C expression have not been described before in endothelial cells. Native HDL3 increased MMP-1 and MMP-14 expression and decreased MMP-13 expression, whereas oxidized HDL3 increased PAI-1 and MMP-1 expression. The expression pattern was confirmed by quantitative real-time PCR. In summary, a large repertoire of matrix-degrading proteases is expressed in endothelial cells, an expression that can be modulated by native and oxidized HDL3.     

A patient with novel MBOAT7 variant: The cerebellar atrophy is progressive and displays a peculiar neurometabolic profile

Mutations in the MBOAT7 gene have been described in 43 patients, belonging to 18 families, showing nonspecific clinical features (intellectual disability [ID], seizures, microcephaly or macrocephaly, and mild to moderate cerebellar atrophy) that make the clinical diagnosis difficult. Here we report the first Italian patient, a 22.5‐year‐old female, one of the oldest reported, born to apparently consanguineous parents. She shows severe ID, macrocephaly, seizures, aggressive outbursts, hyperphagia. We also documented progressive atrophy of the cerebellar vermis, that appeared not before the age of 7. The whole‐exome sequencing of the trio identified a novel homozygous variant c.1057_1058delGCinsCA (p.Ala353His) in the MBOAT7 gene. The variant is considered to be likely pathogenic, since it is absent from population database and it lies in a highly conserved amino acid residue. This disorder has a neurometabolic pathogenesis, implicating a phospholipid remodeling abnormalities. A brain hydrogen‐magnetic resonance spectroscopy (H‐MRS) examination in our patient disclosed a peculiar neurometabolic profile in the cerebellar hemispheric region. This new finding could address the clinical suspicion of MBOAT7‐related disorder, among the wide range of genetic conditions associated with ID and cerebellar atrophy. Moreover, the documented progression of cerebellar atrophy and the worsening of the disease only after some years open to the possibility of a therapeutic window after birth.     

XX sex reversal, palmoplantar keratoderma, and predisposition to squamous cell carcinoma: genetic analysis in one family

We describe a large inbred Sicilian family that includes four 46, XX (SRY-) brothers. Palmoplantar hyperkeratosis (PPK) and an associated predisposition to squamous cell carcinoma (SCC) of the skin, segregates as a recessive trait within the family. Interestingly, all the PPK-affected members of the family are phenotypic males (46,XY or 46,XX) while seven XX sibs are healthy phenotypic females with no signs of PPK. We propose that homozygosity for a single mutational event, possibly including contiguous genes, may cause PPK/SCC in both XY or XX individuals and sex reversal in XX individuals. The family is informative for linkage analysis for the PPK trait and allows linkage exclusion for the sex reversal trait. Here we show that 15 loci involved in PPK etiology, skin differentiation, function or malignancy, and nine loci involved in sex determination/differentiation are not implicated in the phenotype of this family.     

Laser-ultraviolet-A-induced ultraweak photon emission in mammalian cells

Photobiological research in the last 30 yr has shown the existence of ultraweak photon emission in biological tissue, which can be detected with sophisticated photomultiplier systems. Although the emission of this ultraweak radiation, often termed biophotons, is extremely low in mammalian cells, it can be efficiently increased by ultraviolet light. Most recently it was shown that UV-A (330 to 380 nm) releases such very weak cell radiation in differentiated human skin fibroblasts. Based on these findings, a new and powerful tool in the form of UV-A-laser-induced biophotonic emission of cultured cells was developed with the intention to detect biophysical changes between carcinogenic and normal cells. With suspension densities ranging from 1 to 8 x 10(6) cells/mL, it was evident that an increase of the UV-A-laser-light induced photon emission intensity could be observed in normal as well as melanoma cells. Using this new detection procedure of ultraweak light emission, photons in cell suspensions as low as 100 microL could be determined, which is a factor of 100 lower compared to previous procedures. Moreover, the detection procedure has been further refined by turning off the photomultiplier system electronically during irradiation leading to the first measurements of induced light emission in the cells after less than 10 micros instead of 150 ms, as reported in previous procedures. This improvement leads to measurements of light bursts up 10(7) photons/s instead of several hundred as found with classical designs. Overall, we find decreasing induction ratings between normal and melanoma cells as well as cancer-prone and melanoma cells. Therefore, it turns out that this highly sensitive and noninvasive device enables us to detect high levels of ultraweak photon emission following UV-A-laser-induced light stimulation within the cells, which enables future development of new biophysical strategies in cell research.