Predictive role of natural killer cells in bronchoalveolar lavage fluid of patients with sarcoidosis.

Sarcoidosis is a rare granulomatous disease of unknown aetiology belonging to the wide group of interstitial lung diseases.). Although the limitlessness of BAL fluid is debated, it remains one of the best matrices for studying the pathogenesis of sarcoidosis. Natural killer (NK) cells have been described in BAL fluid from sarcoidosis patients. Elevated NK cells in BAL fluid from sarcoidosis patients have been found to be associated with poor outcomes. In this study, NK cells were evaluated in BAL samples from sarcoidosis patients at the time of diagnosis and associated with clinical characteristics in order to evaluate their prognostic role. Of the 276 patients suspected to have sarcoidosis on the basis of clinical and radiological findings, 248 had a final diagnosis of sarcoidosis. Clinical parameters, Scadding stage, and extrapulmonary localization were collected in a database. It resulted in fibrotic sarcoidosis patients being associated with an increase in lymphocyte percentages in BAL samples, particularly NK cells when compared with other groups. From ROC analysis, NK cell percentages in BAL samples resulted as being the best predictive markers in discriminating stage 4 of sarcoidosis from other RX stages (AUC=0.85, p<0.0001). Furthermore, after the stratification of patients on the basis of the number of extrapulmonary localizations, patients with an higher number of extrapulmonary localizations also showed higher percentages of NK cells in BAL fluid. In conclusion, NK cell percentages in BAL fluid can be considered a good prognostic marker of fibrotic phenotypes of sarcoidosis and involvement of other organs, although their diagnostic utility was poor.

Prognostic bioindicators in severe COVID-19 patients.

BACKGROUND: Severe acute respiratory syndrome caused by novel coronavirus 2 (SARS-CoV-2) emerged in Wuhan (China) in December 2019. Here we evaluated a panel of biomarkers to phenotype patients and to define the role of immuno-inflammatory mediators as biomarkers of severity. MATERIALS AND METHODS: Serum samples were obtained from 24 COVID-19 patients on admission to hospital, before any treatment or infusion of intravenous steroids or invasive ventilation. KL-6 IL-6 and C-peptide were measured by chemiluminescent enzyme immunoassay. IL-6 assay was validated for accuracy and precision. The validity of variables used to distinguish severe from mild-to-moderate patients was assessed by areas under curves (AUC) of the receiver operating characteristic (ROC) and logistic regression was performed to combine parameters of the two groups. RESULTS: In the severe group, IL-6, CRP and KL-6 concentrations were significantly higher than in mild-to-moderate patients. KL-6, IL-6 and CRP concentrations were directly correlated with each other. ROC curve analysis of the logistic regression model including IL-6, KL-6 and CRP showed the best performance with an AUC of 0.95. CONCLUSIONS: Besides corroborating previous reports of over-expression of IL-6 in severe COVID-19 patients requiring mechanical ventilation, analytical determination of other mediators showed that IL-6 concentrations were correlated with those of KL-6 and CRP. The combination of these three prognostic bioindicators made it possible to distinguish severe COVID-19 patients with poor prognosis from mild-to-moderate patients.

Right cardiac involvement in lung diseases: a multimodality approach from diagnosis to prognostication.

Lung diseases are amongst the main healthcare issues in the general population, having a high burden of morbidity and mortality. The cardiovascular system has a key role in patients affected by respiratory disorders. More specifically, the right ventricle (RV) enables the impaired lung function to be overcome in an initial stage of disease process, reducing the severity of dyspnoea. In addition, two of the main causes of death in this setting are RV failure and sudden cardiac death (SCD). Echocardiography is regarded as a useful and easily available tool in assessing RV function. Several noninvasive echocardiographic parameters of elevated pulmonary pressures and RV function have been proposed. The combination of different parameters and imaging methods is paramount and researches regarding RV impairment using these indices has been specifically addressed in relation to the chronic obstructive and restrictive lung disease in order to guide the clinicians in the management of these patients. Cardiac involvement in lung diseases is often observed, and RV changes are reported also in early stages of pulmonary diseases. The role of right ventricle in chronic respiratory disease patients has to be evaluated in detail to describe the response to therapy and the degree of disease progression through multimodality and advanced imaging techniques. The aim of this review is to describe the different pathophysiological mechanisms of cardiac impairment in primary lung disease (such as chronic obstructive pulmonary disease (COPD), idiopathic pulmonary fibrosis (IPF) and sarcoidosis) and to summarize the role of cardiac multimodality imaging in the diagnosis and the prognosis of these diseases.

Effects of rituximab therapy on B cell differentiation and depletion.

Rituximab is a human/murine chimeric anti-CD20 monoclonal antibody. It is largely used to treat B cell malignancies and has become standard in the management of B cell­mediated diseases such as rheumatoid arthritis and granulomatosis with polyangitis. The effects of rituximab need to be monitored by B cell phenotyping. Evaluate possible surface markers for monitoring B cell development in response to rituximab treatment. This review discusses the literature on the B cell surface markers analysed by flow cytometry in patients treated with rituximab. A panel of biomarkers of response to treatment to monitor by flow cytometry is also suggested. B cell phenotyping is useful to predict clinical relapses after rituximab treatment. The proposed panel of biomarkers includes CD38++CD24++IgD+/- immature B cells and IgD-CD38+/- memory B cells. In responders, Th1/Th2 balance and tolerance cells (CD4+CD25+CD127-/low Treg cells and CD19+CD24hiCD38hi Breg cells) tend to be restored after rituximab therapy. Furthermore, in responder patients, indirect depletion of CD19+/-CD27++CD38++ preplasma cells can be proposed as a predictor of response. Flow cytometric analysis of samples from patients treated with rituximab is a useful strategy to stratify patients according to response to treatment. Identification of B cell differentiation stages by means of a specific flow cytometry panel could improve monitoring of rituximab effects and enable non-responders to be distinguished from good responders.

NK and NKT-like cells in granulomatous and fibrotic lung diseases.

ABTRACT: Background The pathogenetic and regulatory roles of natural killer (NK) and natural killer T-like cells in interstitial lung diseases (ILDs), fibrotic and granulomatous of unknown etiology are unclear. Objectives Here we investigated NK and NKT-like cells in peripheral blood (PB) and Bronchoalveolar lavage (BAL) from patients with ILDs. Method 190 patients (94 male mean age 61 ± 14.3 years) and 8 controls undergoing bronchoscopy for ILD diagnostic work-up were enrolled consecutively; 115 patients sarcoidosis, 24 chronic fibrotic hypersensitivity pneumonitis and 43 patients other ILDs [32 idiopathic pulmonary fibrosis (IPF) and 11 non-specific interstitial pneumonia (NSIP)]. PB and BAL were processed by flow cytometry using monoclonal antibodies to differentiate NK and NKT-like cells. Results NK% in BAL was significantly different among ILDs (p = 0.02). Lower NK% was observed in BAL from sarcoidosis than other ILDs (p < 0.05). Similar findings were observed for NKT-like, whereas no differences were found for PB NK%. Difference of NK% was observed between BAL and PB in all groups (p < 0.001). Sarcoidosis patients reported the best area under the curve for NKT-like (AUC = 0.678, p = 0.0015) and NK cells (AUC = 0.61, p = 0.001). In the IPF-NSIP subgroup, NK% cell was inversely correlated with FVC% (r = - 0.34, p = 0.03) and DLCO% (r = - 0.47, p = 0.0044). Conclusions NK and NKT-like were expressed differently in BAL from patients with different ILD and were significantly depleted in sarcoidosis respect to other ILDs. This suggests that these cells may play a protective role in the pathogenesis of sarcoidosis.

Automated Intelligent Microscopy for the Recognition of Decoy Cells in Urine Samples of Kidney Transplant Patients.

BACKGROUND: BK virus (BKV)-associated nephropathy is definitely involved in allograft failure after kidney transplant. Thus, the need for an early control of viral reactivation in immunocompromised patients is well established. Determination of urinary release of decoy cells (DC) and BK viral load in plasma and urine by polymerase chain reaction (PCR) usually precedes renal biopsy. The aim of the study is to assess viral reactivation by BKV-DNA PCR and DC detection in urinary sediment using automated intelligent microscopy. METHODS: Seventy-eight kidney transplant patients were analyzed for the presence of plasma BKV-DNA by quantitative TaqMan real-time PCR. Additionally, automated intelligent microscopy was used for urine sediment analysis, allowing to count cells with decoy feature, confirmed by phase contrast microscopic review. RESULTS: Plasma BKV-DNA PCR was detected in 14 (17.9%) patients. DC were identified in 19 (24.3%) urine sediments by automated analyzers and confirmed by microscopic observation. Two patients were BKV-DNA-positive/DC-negative; conversely, 7 subjects were DC-positive/BKV-DNA-negative. CONCLUSIONS: Plasma quantification of BK viral load is currently the best noninvasive method for the detection of viral reactivation. Nevertheless, automated methods to screen for the presence of DC in urine could facilitate early BK virus replication diagnosis and patient follow-up by quantitative and visual results.

Gold nanoparticles as scaffolds for poor water soluble and difficult to vehiculate antiparkinson codrugs.

We report the facile and non-covalent preparation of gold nanoparticles (AuNPs) stabilized by an antiparkinson codrug based on lipoic acid (LA). The obtained AuNPs appear stable in both dimethyl sulfoxide and fetal bovine serum and able to load an amount of codrug double the weight of gold. These NPs were demonstrated to be safe and biocompatible towards primary human blood cells and human neuroblastoma cells, one of the most widely used cellular models to study dopaminergic neural cells, therefore are ideal drug carriers for difficult to solubilize molecules. Very interestingly, the codrug-stabilized AuNPs were shown to reduce the accumulation of reactive oxygen species in SH-SY5Y cells treated with LD and did not change total oxidant status levels in cultured human blood cells, thus confirming the antioxidant role of LA although bound to AuNPs. The characterization of AuNPs in terms of loading and stability paves the way for their use in biomedical and pharmacological applications.

Modulation of coupling in the Escherichia coli ATP synthase by ADP and Pi: Role of the ε subunit C-terminal domain.

The ε-subunit of ATP-synthase is an endogenous inhibitor of the hydrolysis activity of the complex and its α-helical C-terminal domain (εCTD) undergoes drastic changes among at least two different conformations. Even though this domain is not essential for ATP synthesis activity, there is evidence for its involvement in the coupling mechanism of the pump. Recently, it was proposed that coupling of the ATP synthase can vary as a function of ADP and Pi concentration. In the present work, we have explored the possible role of the εCTD in this ADP- and Pi-dependent coupling, by examining an εCTD-lacking mutant of Escherichia coli. We show that the loss of Pi-dependent coupling can be observed also in the εCTD-less mutant, but the effects of Pi on both proton pumping and ATP hydrolysis were much weaker in the mutant than in the wild-type. We also show that the εCTD strongly influences the binding of ADP to a very tight binding site (half-maximal effect≈1nM); binding at this site induces higher coupling in EFOF1 and increases responses to Pi. It is proposed that one physiological role of the εCTD is to regulate the kinetics and affinity of ADP/Pi binding, promoting ADP/Pi-dependent coupling.

Assessment of NGAL as an early biomarker of acute kidney injury in adult cardiac surgery patients.

Early and predictive acute kidney injury (AKI) markers may be decisive for the clinical outcome of heart surgery. Hence, this study set out to evaluate the biological variability of urinary neutrophil gelatinase-associated lipocalin (uNGAL) levels in adult cardiac surgery patients, to test their feasibility as a biomarker of early AKI in a routine laboratory setting. uNGAL levels were measured with an automated immunoassay in urine samples from patients undergoing cardiac surgery using cardiopulmonary bypass, at the time of admission (T0) and 4 hours (T1) and 24 hours (T2) after surgery. Patients without post-operative AKI did not show significant differences in urine NGAL levels after surgery. In contrast, patients developing AKI displayed a significant increase (P=0.011) in uNGAL levels compared to T0. This increase was detectable at an earlier time point (T1, 4 hours) with respect to serum creatinine (T2, 24 hours). Confirming its utility as a biomarker, at T1 the uNGAL levels were significantly higher in AKI patients than in non-AKI patients (P=0.021). A receiver operating characteristic curve analysis of the uNGAL assay gave a sensitivity of 55.3 (95percent confidence interval, 26.59-78.73), a specificity of 72.9 (95 percent CI, 55.88-86.21), and a cut-off value for AKI prediction of 55.2. These results support the notion that urinary NGAL is an earlier marker of AKI than serum creatinine. However, the cut-off value of the assay was too low to consider it as a positive or negative diagnostic marker in AKI patients with moderate degree of severity. Likewise, its sensitivity and specificity were not high enough for it to be considered better than the others currently in use.

Atherosclerosis: a classic inflammatory disease.

Atherosclerosis is an inflammatory disease due to a diet high in saturated fat, hypercholesterolemia, obesity, hypoglycemia, etc. mainly mediated by the infiltration of macrophage and T cells into the vascular wall. Once the endothelial is damaged monocytes penetrate the tissue and are transformed in scavenger cells. Upon stimulation of Th1 cells, a group of cytokines is released and contributes to the inflammatory response of atherosclerotic tissue. When macrophages proliferate they amplify inflammatory response through the secretion of growth factors and cytokines such as TNF and IL-1. In addition, chemokines such as RANTES and other C-C chemokines are generated, and matrix metalloprotinease 9 (MMP-9) are produced by activated monocytes. However, the immune system in atherosclerosis still remains unclear. Here, in this study we revisited the inter-relationship between atherosclerosis and inflammation.

Increased vascular endothelial growth factor levels in aqueous humor and serum of patients with quiescent uveitis.

PURPOSE: Vascular endothelial growth factor (VEGF) and interleukin-8 (IL-8) are angiogenic mediators that share a significant proinflammatory activity. Both substances have been suggested to play a key role in uveitis pathogenesis. The authors analyzed VEGF and IL-8 levels in the aqueous humor and serum of patients with different types of uveitis during a quiet phase of the disease. METHODS: Thirteen patients with intermediate uveitis, uveitis associated with ankylosing spondylitis, Vogt-Koyanagi-Harada disease, Fuchs uveitis syndrome, idiopathic chronic anterior uveitis, or Behcet disease, as well as 10 normal matched subjects, were included in the study. VEGF and IL-8 concentrations were measured in aqueous humor and serum by enzyme-linked immunosorbent assay. RESULTS: VEGF levels were significantly higher in both the aqueous humor and serum of patients with uveitis as compared with controls. IL-8 concentrations in aqueous humor were significantly higher in patients with uveitis with extraocular manifestations than in those with eye-limited disease. CONCLUSIONS: These findings suggest that VEGF plays a role in uveitis pathogenesis even during inactive disease and that IL-8 levels are significantly influenced by the presence of uveitis-associated extraocular changes.

[Severe renal failure in a child]. / Insufficienza renale ad esordio acuto in un bambino.

A four-year-old male child was admitted with severe renal failure, apparently recent in onset and he was treated with peritoneal dialysis (PD). A renal biopsy showed interstitial cellular infiltration with crystals within the tubules and sclerotic glomeruli. Type I hyperoxaluria was diagnosed and the child received a liver and kidney transplant after 10 months of dialysis. Two years later, he has normal renal function, and blood and urine oxalate levels are within normal ranges.

Characterization of the conformational behavior of peptide Contryphan Vn: a theoretical study.

In this work we report the study of a peptide, the Contryphan Vn produced by Conus ventricosus, a vermivorous cone snail living in the temperate Mediterranean sea. This cyclic peptide of nine residues is a ring closed by a Cys-Cys (Cys: cysteine) disulfide bond containing two proline (Pro) residues and two tryptophans (Trp), one of them being a D-Trp. We present a statistical mechanical characterization of the peptide, simulated in water for about 200 ns with classical molecular dynamics (MD). In recent years there has been a growing interest in the study of the mechanics and dynamics of biological molecules, and in particular for proteins and peptides, about the relationship between collective motions and the active conformations which exert the biological function. To this aim we used the essential dynamics analysis on the MD trajectory and extracted, from the total fluctuations of the molecule, the dominant dynamical modes responsible of the principal conformational transitions. The Contryphan Vn small size allowed us to investigate in details the all-atoms dynamics and the corresponding thermodynamics in conformational space defined by the most significant intramolecular motions.

Generation and characterization of epidermolysis bullosa simplex cell lines: scratch assays show faster migration with disruptive keratin mutations.

BACKGROUND: Epidermolysis bullosa simplex (EBS) is an inherited skin fragility disorder caused by mutations in keratin intermediate filament proteins. While discoveries of these mutations have increased understanding of the role of keratins and other intermediate filaments in epithelial tissues, progress towards the development of therapy for these disorders is much slower. OBJECTIVES: Cell culture model systems that display these structural defects are needed for analysis of the cellular consequences of the mutations and to enable possible therapeutic strategies to be developed. Our aim was to generate immortalized cell lines as such model systems for the study of EBS. METHODS: We generated a series of stable cell lines expressing EBS-associated keratin mutations, by immortalizing keratinocytes from EBS-affected skin biopsies with either simian virus 40 (SV40) T antigen or human papillomavirus 16 (HPV16) E6/E7, and assessed their keratin expression (by immunofluorescence), proliferation rates and migratory behaviour (in outgrowth and scratch wound assays). RESULTS: Clonal immortalized keratinocyte cell lines KEB-1, KEB-2, KEB-3 (using SV40 T antigen) and KEB-4, KEB-7 and NEB-1 (using HPV16 E6/E7) were established. These include two lines from a single individual with Weber-Cockayne EBS (i.e. KEB-3 and KEB-4, mutation K14 V270M), and three cell lines from a second family, two from siblings carrying the same mutation (KEB-1, KEB-2 lines from Dowling-Meara EBS, mutation K5 E475G) and one from an unaffected relative (NEB-1). The sixth cell line (KEB-7), with a previously unreported severe mutation (K14 R125P), was the only one to show keratin aggregates in resting conditions. Despite variations in the immortalization procedure, there was no significant difference between cell lines in keratin expression, outgrowth capabilities or response to transient heat shock. However, cell migration, as measured by speed of scratch wound closure, was significantly faster in cells with severe EBS mutations. CONCLUSIONS: These cell lines provide useful culture systems in which to assess aspects of EBS-induced cell changes. The faster migration after scratch wounding of the EBS keratinocytes may be a consequence of the known upregulation of stress-activated kinase pathways in these cells.

Effect of dietary fish oil on insulin sensitivity and metabolic fate of glucose in the skeletal muscle of normal rats.

The aim of this work was to study the effect of the administration of cod liver oil on the non-oxidative and oxidative fate of glucose metabolism in the skeletal muscle of normal rats. To achieve this goal, the gastrocnemius was examined regarding glucose oxidation, glycogen synthase activity and glycogen storage both at baseline and during euglycemic hyperinsulinemic clamping. The results show that dietary fish oil decreases plasma insulin levels without alteration in glucose homeostasis (at baseline). In addition, the observed enhancement in whole body glucose utilization during clamping suggests an increased peripheral insulin sensitivity. Furthermore, under insulin-stimulated glucose disposal, an enhancement in the glycolytic pathway (increased levels of muscle glucose-6-phosphate and plasma lactate) rather than changes in the oxidation (pyruvate dehydrogenase complex) and storage components of glucose metabolism was observed in the skeletal muscle of rats fed dietary fish oil. These results coupled with the hypolipidemic effects of fish oil may have implications for the prevention and/or management of some pathological states manifested by insulin resistance with or without dyslipidemia.

Epileptic seizures may begin hours in advance of clinical onset: a report of five patients.

Mechanisms underlying seizure generation are traditionally thought to act over seconds to minutes before clinical seizure onset. We analyzed continuous 3- to 14-day intracranial EEG recordings from five patients with mesial temporal lobe epilepsy obtained during evaluation for epilepsy surgery. We found localized quantitative EEG changes identifying prolonged bursts of complex epileptiform discharges that became more prevalent 7 hr before seizures and highly localized subclinical seizure-like activity that became more frequent 2 hr prior to seizure onset. Accumulated energy increased in the 50 min before seizure onset, compared to baseline. These observations, from a small number of patients, suggest that epileptic seizures may begin as a cascade of electrophysiological events that evolve over hours and that quantitative measures of preseizure electrical activity could possibly be used to predict seizures far in advance of clinical onset.

Effector Th-1 cells with cytotoxic function in the intestinal lamina propria of patients with Crohn's disease.

A large body of evidence points to a pivotal relationship between Th-1 cells and mucosal inflammation in Crohn's disease (CD). The aim of the present study was to assess whether CD is associated with specific functional activity of lamina propria T lymphocytes (LPT), particularly purified CD4, such as cytotoxic activity and specific cytokine-secreted profile. The results showed that CD4 LPT in patients displayed a chronically activated memory-like surface phenotype and, when compared to controls, had a significantly enhanced antibody-redirected cytotoxicity. Interestingly, the ratio of perforin expression in CD4 LPT was higher compared to controls, and a redirected lysis of human RBC mediated by a CD4 subset of intestinal lamina propria was evident, suggesting a cytolytic pore-forming mechanism. Moreover, a unique Th-1 cytokine profile pattern in the CD4 cells from CD was defined. These effector cells produced 12 times more IFN-gamma, two times more TNF-alpha, and three times less IL-4 than controls. In contrast, no increase in IL-2 was detected, while IL-5 was undetectable. Our studies suggest that these preexisting in vivo activated CD4 LPT may play an important role in the inflammatory process in CD, thus directly contributing to the intestinal lesions.

Role of skeletal muscle on impaired insulin sensitivity in rats fed a sucrose-rich diet: effect of moderate levels of dietary fish oil.

In the present study we investigated: (1) the contribution of the skeletal muscle to the mechanisms underlying the impaired glucose homeostasis and insulin sensitivity present in dyslipemic rats fed a sucrose-rich diet (SRD) over a long period of time and (2) the effect of fish oil on these parameters when there was a stable hypertriglyceridemia before the source of fat (corn oil) in the diet was replaced by isocaloric amounts of cod liver oil. Our results show an increased triglyceride content in the gastrocnemius muscle with an impaired capacity for glucose oxidation in the basal state and during euglycemic clamp. This was mainly due to a decrease of the active form of pyruvate dehydrogenase complex (PDHa) and an increase of PDH kinase activities. Hyperglycemia, normoinsulinemia, and diminished peripheral insulin sensitivity also were found. Even though there were no changes in the insulin levels, the former metabolic abnormalities were completely reversed when the source of fat was changed from corn oil to cod liver oil. The data also suggest that in the gastrocnemius muscle of rats fed a SRD over an extended period, an increased availability and oxidation of the lipid fuel, which in turn impairs the glucose oxidation, contributes to the abnormal glucose homeostasis and to the peripheral insulin insensitivity. Moreover, the parallel effect on insulin sensitivity, glucose, and lipid homeostasis attained through the manipulation of dietary fat (n-3) in the SRD suggests a role of n-3 fatty acid in the management of dyslipidemia and insulin resistance.

Mutation and transcription analysis of transthyretin gene in Italian families with hereditary amyloidosis: a putative novel hot spot' in codon 47.

Transthyretin gene mutations are associated with autosomal dominant familial amyloidosis. The commonest phenotype in the patients is peripheral neuropathy, but restrictive cardiomyopathy is also a frequent sign. More than 70 different mutations in the gene have been described. Although these mutations are randomly distributed, some hot spots have also been reported notably at position 6, 30, 33, 58, 109, 119 and 122. A few of these codons contain a CpG dinucleotide. We describe an additional 'hot spot' occurring at codon 47, in which we report one novel and two previously described mutations. This codon, however, does not contain a CpG dinucleotide, suggesting that other mechanisms might be responsible for the allelic heterogeneity. All the reported mutations in codon 47 are located in the exon 2 consensus sequence and are potentially involved in splicing. We performed transcription analysis on two livers obtained from transplanted patients carrying the Ala47 mutation. These livers showed a normally spliced message, indicating that this mutation does not affect splicing.

Mutations in the laminin alpha2-chain gene in two children with early-onset muscular dystrophy.

We investigated two children who presented with delayed motor milestones. The first was a girl who was referred at 20 months because of developmental delay. She walked at 28 months and currently, aged 5 years, is independently mobile but has difficulty rising from the floor or going upstairs. The second was also a girl who presented at 6 weeks of age with hypotonia. Her motor milestones were delayed and she walked at the age of 2 years and 8 months and is currently independently mobile at the age of 3 years. Serum creatine kinase was elevated and a muscle biopsy showed dystrophic changes in both children. Immunohistochemistry of the laminin alpha2 chain of merosin was very similar in both cases: using a C-terminal antibody that recognizes an 80 kDa fragment, there was a mild reduction in expression on most fibres, while the staining with another antibody that recognizes a 300 kDa fragment showed a very marked reduction. Mutational analysis of the laminin alpha2 chain gene in the first patient showed that one of the two alleles had a de novo single nucleotide deletion at position 5702, causing a frameshift. In the other allele, we identified two point mutations present in cis; one was a G-->C transition at position +5 while the second was a T-->C transition at position +6 of the conserved donor splicing consensus sequence of introns 37 and 63, respectively. Transcription analysis of the corresponding cDNA region did not show any alternative splicing occurring as a result of these splice site mutations. Therefore, these mutations probably affect the splicing efficiency. Interestingly, the second child carried in both alleles the same two splicing consensus sequence mutations found in cis in the first patient. Our data provide further evidence that mutations in the laminin alpha2 chain gene are responsible not only for the severe form of congenital muscular dystrophy with onset at birth, but also for milder phenotypes, with later onset, in which the synthesis of a partially functional protein, or of a normal protein but in reduced quantity, is possible. The finding that these two unrelated patients had the same unusual mutation in common might suggest that this is a relatively commonly allele responsible for partial merosin deficiency in the UK.