The value of immunohistological screening in the production of monoclonal antibodies

This paper describes an immunoperoxidase technique for labelling cryostat tissue sections which is routinely used in the authors' laboratories both in the initial screening of hybridoma culture supernatants, and also during the subsequent cloning and growth of antibody-secreting cell lines. The technique can readily be performed on 100 samples in less than 3 h and is free of non-specific background labelling. The staining pattern of a monoclonal antibody on a single tissue section allows semiquantitative assessment of its reactivity against a wide variety of tissue constituents and is thus inherently much more informative than conventional screening techniques (such as binding assays) which yield only a single numerical value for each test performed. In consequence it is often possible to identify the probable specificity of a new monoclonal antibody at the primary screening stage. A further important advantage of immunohistological screening is that it detects antigens on cells or other tissue structures which do not readily enter suspension and also antibodies against nuclear and cytoplasmic antigens.Examples of monoclonal antibodies analysed by immunohistological screening include antibodies against C3b receptor, HLA-DR, factor VIII-related antigen, human syncytiotrophoblast, dendritic reticulum cells and a proliferation-associated cell surface glyco-protein.     

Reflex sympathetic dystrophy in children: review of a clinical series and description of the particularities in children

Few series on reflex sympathetic dystrophy syndrome (RSDS) have included children. The present series reviewed 10 affected children. The group consisted of 9 girls and one boy with an average age at onset of 11 years (5 years to 16 years). The diagnosis was based on the clinical findings of pain, dysesthesia and autonomic system dysfunction. All patients underwent x rays and bone scans. Their results showed great variation. Minor trauma was the most common trigger factor. The lower extremities were more often involved. The treatment consisted of pain relief and progressive mobilization. Less conventional treatments in children, such as calcitonin and bisphosphonate were also used. The severity and duration of the disease varied greatly among these children. Moderate pain and sympathetic dysfunction persisted often up to two years after onset. Reflex sympathetic dystrophy is more common in children than previously thought. There are differences with the adult form in presentation and clinical course: the diagnosis is often delayed, the lower extremities are more often involved, girls are affected more often and idiopathic forms are frequent. Significant emotional dysfunction is found in a majority of patients and they are best treated as inpatients by a multidisciplinary team.     

Survival and developmental disability in infants with birth weights of 501 to 800 grams, born between 1979 and 1994

OBJECTIVE: Because the survival rate has increased for extremely low birth weight neonates, many have raised the concern that the rate of developmental disability among survivors will also increase. To address this concern, we analyzed changes over time in survival and major neurosensory impairment in a sample of extremely low birth weight infants born between July 1, 1979, and June 30, 1994. METHODS: The study sample included 513 infants with birth weights of 501 to 800 g who were cared for in either of the two neonatal intensive care units that serve a 17-county region in northwest North Carolina and who were born to mothers residing in that region. At 1 year of age (corrected for gestation), survivors were examined by a pediatrician and were tested using the Bayley Scales of Infant Development. Major neurosensory impairment was defined as cerebral palsy, a Bayley Mental Developmental Index <68, or blindness. A total of 209/216 (97%) of survivors were examined at 1 year of age. Epoch of birth was defined as follows: epoch 1, July 1, 1979 to June 30, 1984; epoch 2, July 1, 1984 to June 30, 1989; and epoch 3, July 1, 1989 to June 30, 1994. RESULTS: Survival rates for epochs 1, 2, and 3 were, respectively, 24/120 (20%), 63/175 (36%), and 129/218 (59%). In contrast, the proportions with a major neurosensory impairment did not increase over time; rates for successive epochs were 6/24 (25%), 17/61 (28%), and 26/124 (21%). Rates of cerebral palsy were 3/24 (13%), 12/61 (20%), and 9/124 (7%); rates of delayed mental development were 4/24 (17%), 12/61 (20%), and 17/124 (14%); and rates of blindness were 2/24 (8%), 0/62, and 5/124 (4%), respectively. CONCLUSIONS: This analysis suggests that the increasing survival of extremely low birth weight neonates since the late 1970s has not resulted in an increased rate of major developmental problems identifiable at 1 year of age.