Association of P53 nuclear overexpression and tumor progression in carcinoma in situ of the bladder

We investigated the prevalence and clinical relevance of p53 nuclear overexpression, as detected by antibody PAb1801 and immunohistochemistry, in 33 patients with carcinoma in situ of the bladder. Median followup was 124 months. Disease progressed in 16 patients (48%) during followup. The association between p53 nuclear overexpression and tumor progression was assessed by multivariate analysis, controlling for possible confounding variables, such as patient age and sex, presence of associated stage Ta bladder tumor and adjuvant bacillus Calmette-Guerin therapy. Patients were stratified into 2 groups according to the per cent of tumor cells displaying p53 nuclear overexpression: group 1-18 with less than 20% tumor cells positive and group 2-15 with 20% or more tumor cells positive. Disease progressed in 3 patients (16.7%) in group 1 and in 13 (86.7%) in group 2 (p < 0.0001). Detection of p53 nuclear overexpression in 20% or more tumor cells was the only independent marker of tumor progression in univariate and multivariate analyses (p = 0.004, adjusted relative risk 8.6, 95% confidence interval 2 to 40). Death specifically from bladder cancer was also associated with this altered pattern of p53 expression (p = 0.01, Fisher's exact test). We conclude that p53 nuclear overexpression is an early event in bladder cancer, occurring in 48% of cases of carcinoma in situ of the bladder. Our results also suggest that p53 nuclear overexpression offers significant clinical information and may be a useful tool in the selection of therapy for patients with carcinoma in situ of the bladder.

Evaluation of nedocromil sodium 2% ophthalmic solution for the treatment of seasonal allergic conjunctivitis

During peak ragweed season, 86 patients with seasonal allergic conjunctivitis participated in a 9-week, multicenter, double-masked, placebo-controlled, group-comparative study testing the efficacy and safety of bid nedocromil sodium, 2% ophthalmic solution. The clinical effectiveness of nedocromil sodium was measured by analyzing the means of patient daily symptom scores and eye examinations after 1, 3, 5, and 8 weeks of treatment. The use of nedocromil sodium during peak ragweed pollen season reduced symptom scores with statistically significant treatment differences as compared with the placebo for itchy eyes, tearing, overall eye condition, and symptom summary score. Clinician assessments also favored the use of nedocromil sodium as indicated by significant improvements in tearing, conjunctival injection, and conjunctival edema. No significant side effects were reported by the patients, allergists, or ophthalmologists. We conclude that nedocromil sodium, 2% ophthalmic solution, administered bid is more effective in the relief of symptoms of seasonal allergic conjunctivitis than placebo and causes no major side effects.

Spontaneous cerebrospinal fluid rhinorrhea with associated sinusitis and allergic rhinitis

The entity of spontaneous cerebrospinal fluid rhinorrhea is a rare condition that presents a special challenge to the practicing allergist. Delayed diagnosis can be associated with significant morbidity and mortality. We describe two cases of this condition occurring in association with allergic rhinitis and sinusitis. The presentation and management of these cases is described. A high index of suspicion for this condition should be maintained in all patients who present with profuse and often unilateral rhinorrhea.

Hepatoid adenocarcinoma in the urinary bladder. Unusual localization of a newly recognized tumor type

A tumor mass resected from the anterior bladder wall of a 68-year-old woman displayed unusual histologic features: sheets of hepatoid cells merging focally with a secondary glandular pattern of adenocarcinoma. Intracytoplasmic hyaline globules and bile production within the solid areas supported the impression of hepatocytic differentiation. Immunoreactivity for alpha-fetoprotein (AFP) and alpha-1-antitrypsin and a striking canalicular immunostaining pattern for carcinoembryonic antigen and epithelial membrane antigen all indicate hepatocellular differentiation within this bladder tumor. This represents a case of a hepatoid adenocarcinoma located in the urinary bladder. The use of the term "hepatoid" in the literature is reviewed and the reported cases are grouped into two distinct categories of tumors: (1) germ cell tumors with focal hepatoid areas and (2) true hepatoid adenocarcinomas that meet histologic and immunohistochemical criteria for hepatocellular differentiation. AFP-producing tumors without any other feature of hepatocellular differentiation should not be considered as hepatoid tumors. This classification of hepatoid tumors is likely to be important in elucidating the histogenesis and clinicopathologic features of these unusual neoplasms.

Renal myxoma. A report of two cases and review of the literature

Renal myxomas are rare neoplasms. Seven cases have been reported, of which only two are convincingly diagnosed as myxoma; the remaining cases exhibit features of sarcoma, fibroepithelial polyp, or myxolipoma. We report two additional cases; one in a 52-year-old man and another in a 68-year-old woman. They were discovered incidentally by radiological examination. The resected kidney in both patients contained a well-demarcated gelatinous intraparenchymal tumor, which consisted of occasional slender spindle cells scattered in an abundant myxoid stroma, closely resembling myxomas of other sites. The tumor cells showed immunoreactivity for vimentin but not for S-100 protein, epithelial membrane antigen (EMA), CAM 5.2, HHF-35, or smooth muscle actin. Ultrastructural features were of fibroblast-like cells with an elaborate network of cytoplasmic processes. The differential diagnosis of myxoid tumors of the kidney includes myxoid variants of renal sarcomas and carcinomas, renomedullary interstitial cell tumors, and fibroepithelial polyps. It is important to recognize the existence of a renal myxoma, to avoid confusing this benign tumor with the malignant neoplasms with secondary myxoid features that may involve the kidney.

Tobacco smoking, occupation, and p53 nuclear overexpression in early stage bladder cancer

Epidemiological studies show an increased risk of bladder cancer associated with tobacco smoking and occupational exposures. Certain carcinogens in tobacco and occupational exposures cause DNA damage and may produce specific mutations. TP53 is considered a common target for carcinogenic agents, and mutations of this gene are reported to be the most frequent nuclear abnormalities in human cancer. In order to investigate the relationship between tobacco smoking, occupations, and altered patterns of p53 expression, we have analyzed a group of 109 incident patients with superficial transitional cell carcinoma of the bladder. We assessed p53 nuclear overexpression by the use of anti-p53 antibody PAb1801 and immunohistochemistry, and identified 45 of 109 patients (41%) displaying p53-positive phenotype. We observed a significant association between the number of cigarettes smoked per day and p53 nuclear overexpression (p = 0.02). The odds ratios were 2.3 for those smoking 1-2 packs per day and 8.4 for smoking more than 2 packs per day. Similar estimates were obtained after controlling for age, sex, and race. Elevated odds ratios were also observed for dye-/ink-related (odds ratio = 2.0; 95% CI, 0.4-9.4) and cooking-related occupations (1.8, 0.6-5.0), although those were not statistically significant. These data support the hypothesis that certain carcinogens derived from cigarette smoking and occupations may induce TP53 mutations, which in turn are involved in early steps of bladder carcinogenesis.

p53 expression in precancerous gastric lesions: an immunohistochemical study of PAb 1801 monoclonal antibody on adenomatous and hyperplastic gastric polyps

To determine the chronology of p53 mutation in the gastric carcinogenic sequence, we studied p53 overexpression in premalignant lesions, including 17 adenomatous polyps (10/17 surrounded by intestinal metaplasia and 11/17 harboring foci of adenocarcinoma or severe dysplasia), and 18 hyperplastic polyps (4/18 with focal adenomatous changes). Immunohistochemistry with PAb 1801 monoclonal antibody was performed on archival material; p53 nuclear staining was seen in 10/17 adenomas, but was limited to the foci of adenocarcinoma in three cases. Five adenomas with foci of severe dysplasia or carcinoma were nonreactive. Intestinal metaplasia, normal gastric mucosa, and 14/18 hyperplastic polyps were nonreactive. p53 Reactivity observed in four hyperplastic polyps was limited to adenomatous foci. These results suggest that p53 overexpression occurs in dysplastic epithelium of precancerous gastric lesions. Its absence in chronic atrophic gastritis with intestinal metaplasia suggests it is a relatively late event in the gastric carcinogenic sequence.

Blood group antigens in Barrett's esophagus and associated adenocarcinomas

A panel of monoclonal antibodies (MoAbs) against BGAg A, B, and H and Lewis a, b, X, and Y (Le a, Le b, X, Y) was used to characterize and evaluate the blood group antigens (BGAg) immunohistochemistry in Barrett's esophagus (BE) and associated adenocarcinomas (ACA). Thirteen cases of ACA arising in metaplastic columnar epithelium of the distal esophagus were reviewed (12 men; 1 woman; mean age: 59). Twelve cases had juxtaposed BE of different types with low-grade dysplasia in five and high-grade dysplasia in three. ACAs were classified as well differentiated (one case), moderately differentiated (three cases), and poorly differentiated (four cases). Five cases had mixed features. Loss of BGAg H was recorded in four ACA and in one adjacent BE. Loss of BGAg B was noted in three ACAs, but in only one case in the adjacent BE. Incompatible expression of BGAg A and B was present in one case each. Anomalous expression of Le a was seen in seven ACAs and adjacent BE. Loss of Le b was noted in six ACAs. Deletion of X was seen in four ACAs and in BE. Loss of Y was present in the only nonsecretor patient. We conclude that significant alterations of BGAg occur in BE and in associated ACAs. Recognition of these antigenic alterations warrants further investigation to define a role for BGAg immunohistochemistry in the surveillance of BE patients at risk of developing ACA.

Cytomegalovirus, angiomatosis, and Kaposi's sarcoma: new observations of a debated relationship

Kaposi's sarcoma (KS) encompasses a broad spectrum of lesions ranging from foci of muco-cutaneous angiomatosis to tumor masses of internal organs. Its strong association with immune deficiency and the marked differences in incidence between the various populations at risk are suggestive of an infectious etiology. The agent most often suspected of being implicated in the etiology of KS is cytomegalovirus (CMV); however, despite sustained research on this subject, its role remains controversial. The present work includes six cases of KS with a broad variety of lesions in which, with the use of light and electron microscopy, immunohistochemistry, and in situ hybridization, we investigated the presence of CMV and examined its relationship with KS. CMV was present in all six cases and showed a remarkable propensity for the KS lesions where both intranuclear and intracytoplasmic forms were not only next to but frequently within KS cells. Areas of angiomatosis, hemorrhage, and KS had usually an abundance of CMV. Herpes-like virus particles inside KS nuclei were documented by light and electron microscopy and identified as CMV by immunohistochemistry and in situ hybridization. The selective morphologic presence of this virus within the tumor cells, not previously demonstrated, indicates a strong association between CMV and KS, the significance of which remains to be established.

Multicenter placebo-controlled study of nedocromil sodium 1% nasal solution in ragweed seasonal allergic rhinitis

An 8-week double-blind study was carried out in 177 ragweed patients with seasonal allergic rhinitis to compare nedocromil sodium 1% nasal solution (Tilarin, QID, Fisons plc) and placebo. Symptoms of rhinitis were significantly reduced by nedocromil sodium during the peak 3-week pollen season (P = .001 for diary summary score) and the active treatment was rated effective by 74% of patients.

Pigmented melanocytic schwannoma of the uterine cervix

A 47-year-old woman had a lesion of the uterine cervix that presented clinically as a protruding or aborted leiomyoma. Grossly the tumor occupied a substantial portion of the cervical and endocervical region. Histologically it showed a spindle cell neoplasm arranged in large fascicles that penetrated deeply into the fibromuscular wall of the cervix. The tumor cells had abundant pink cytoplasm that contained considerable brown melanin granules confirmed by Fontana's stain. Cytologically nuclear pleomorphism, hyperchromatism, and giant nuclear forms were observed. Mitoses were also seen. Localized nuclear palisading was present. Electron microscopic examination of paraffin-embedded material revealed numerous premelanosomes and opaque granules that were compatible with mature melanosomes, thus confirming melanogenesis in the tumor. Tumor cells exhibited focal projections, and the connective tissue showed abnormal spacing of collagen. Basal lamina material was noted focally on tumor cell surfaces. Immunocytochemistry showed a positive reaction to S-100 protein and HMB-45 in tumor cell cytoplasm.

Renal pathology of essential hypertension

Microscopic analysis of over 2,000 renal biopsies taken at surgical sympathectomy operations has been correlated with blood pressures in essential hypertension. Statistically significant relationships exist between the average diastolic pressure and the degree of afferent renal arteriolar thickening and narrowing. Postoperative prognosis was favorable with all but the most severe and diffuse arteriolar sclerosis, and vascular fibrinoid necrosis did not affect survival. Juxtaglomerular cell hyperplasia and inferred renin hypersecretion were significantly involved in the kidney biopsies of essential hypertension. Diabetic juxtaglomerular cell atrophy and sclerosis reduced this component of hypertension. After age 80, kidneys at autopsy showed no evident relation between arteriolar lesions and hypertension.

Early developmental progress of preterm twins discordant for birthweight and risk

Studies of developmental progress in high-risk twins have disparate findings. In this study, we report the outcome of 45 twin pairs born between 26 and 37 weeks gestation, and whose birthweights ranged from 840 to 2000 g. No significant differences were found for weight, risk and birth order. However, earlier preterm infants were found to have significantly lower mental scores on the Bayley Scales of Infant Development at 24 months, and lower IQ scores on the Stanford Binet Intelligence Scale at 36 months. These findings imply that gestational age is a powerful variable in determining developmental outcome.

The metabolism of C1 inhibitor and C1q in patients with acquired C1-inhibitor deficiency

The metabolism of 125I-labeled C1 inhibitor (C1INH) and C1q was studied in five patients with B cell lymphoproliferative disorders, C1INH deficiency, and angioedema. C1INH catabolism was markedly accelerated in these patients. The fractional catabolic rate (FCR) was 0.053 of the plasma pool per hour compared to that of normal subjects (0.025) or patients with hereditary angioneurotic edema (HANE) (0.035). The catabolism of two dysfunctional proteins Wel and Ta was studied. Protein Wel was catabolized at an accelerated rate (0.041) compared to that in patients with HANE (0.029) or in normal subjects (0.020). In contrast, the FCR of protein Ta was 0.012, which is similar to that in normal patients and in patients with HANE. The extravascular to plasma ratio (E/P) of the normal C1INH in patients was 1.55 compared to 0.60 in normal patients. This is consistent with the rapid extravascular sequestration of the C1INH. The synthesis rate of the C1INH was 0.29 mg/kg/hr in patients that is similar to that in control subjects. The metabolism of C1q was studied in two normal control subjects and three patients. The FCR of C1q was 0.051 in patients compared to 0.023 in control subjects. The E/P was increased in patients (2.8) compared to E/P in control subjects (0.6). The acquisition of C1INH deficiency results from increased consumption of C1INH in vivo.

Chemical dependence and clinical depression in pregnancy

The Short Form of the Beck Depression Inventory (BDI) was administered to 54 chemically dependent pregnant women to assess the extent and depth of depression in the population. The women were divided into three groups by age: Teenagers, young adults, and older adults. Results suggested that this population, as a whole, scored very high on this depression scale. Further, results indicated that the older chemically dependent women scored significantly higher on the depression index than did either of the two younger groups, while the teenagers obtained a mean score comparable to that of the general adolescent population.

RNA content and chromatin structure of CHO cells arrested in metaphase by colcemid

To evaluate the stability of cells arrested in metaphase, cell viability, RNA content, and chromatin structure (the latter probed by the DNA in situ sensitivity to acid-induced denaturation) were studied in uniform-age mitotic CHO cell populations maintained either at 37 degrees C (in the presence of Colcemid) or at 0-4 degrees C for up to 6 h. No significant changes in cell viability and RNA content were seen throughout the experiment for both groups of cells. The sensitivity of DNA in situ to denaturation was significantly increased during the initial 40 min of cell arrest in mitosis. However, no further chromatin changes for up to 6 h were evident regardless of whether cells were kept at 37 degrees C with Colcemid or at 0-4 degrees C in its absence. The data indicate that neither significant deterioration of metaphase cells nor progressive chromatin changes are expected during stathmokinesis experiments in vitro or during the metaphase cell arrest in cytogenetic studies lasting up to 6 h. Also, no RNA turnover can be detected in mitotic cells during this time interval.

Induction of granulocyte histaminase release by particle-bound complement C3 cleavage products (C3b, C3bi) and IgG

The interaction of opsonized particles with human granulocytes promotes a number of important biologic functions, including phagocytosis, superoxide generation, and release of a variety of enzymes, including histaminase. We have previously determined that histaminase release occurs via a C3-dependent process. Although fluid-phase C3b dimers can mediate release, the relative effects of particle-bound C3b and C3bi and of IgG have not been examined. In this report we demonstrate that particle-bound C3 deposited on activators of the alternative C pathway effected histaminase release in the absence of IgG. Particle-bound C3bi and C3b were both effective as mediators of histaminase release. The extent of release varied as a function of the activating surface on which C3 was deposited (zymosan C3b was considerably more potent than C3b bound to rabbit erythrocytes, which was slightly more potent than C3b bound to neuraminidase-treated sheep erythrocytes). In contrast, C3b or C3bi deposited on nonactivating surfaces (such as sheep erythrocytes) at inputs of up to 2,000,000 molecules per granulocyte failed to induce histaminase release unless IgG was also present. The ability of C3b bound to particles that serve as activators of the alternative pathway to induce histaminase release is apparently not the result of decreased susceptibility of C3b to proteolysis or to an increased binding affinity to the C3b receptor, but may relate to the interaction of other surface structures on activating particles with the PMN membrane.

Inhibition of phagocytosis of complement C3- or immunoglobulin G-coated particles and of C3bi binding by monoclonal antibodies to a monocyte-granulocyte membrane glycoprotein (Mol)

Events that lead to phagocytosis of complement (C3)- or IgG-coated particles after their interaction with specific cell surface receptors are poorly understood. Two mouse monoclonal antibodies (an IgM and an IgG2a) to a human granulocyte-monocyte surface membrane differentiation antigen (Mol) inhibited ingestion by granulocytes both of oil Red O particles opsonized with normal human serum or with IgG and of sheep erythrocytes sensitized with IgG. In addition, they specifically inhibited rosetting between phagocytes and sheep erythrocytes coated with C3bi, a fragment of the complement component C3, generated by cleaving C3b with C3b inactivator and beta IH protein. These monoclonal anti-Mol antibodies did not inhibit IgG Fc, C3b or C3d receptor-mediated binding of erythrocytes coated with the respective proteins. The Fab fragment of the IgG2a monoclonal antibody inhibited noncytotoxic enzyme release from granulocytes when these cells were stimulated with zymosan coated with C3bi. Electrophoretic transfer of polymorphonuclear leukocyte detergent lysates to nitrocellulose, followed by immunofixation with monoclonal antibody, showed that these antibodies were directed to a 155,000-mol wt glycoprotein. This surface membrane structure appears to be involved in Fc and C3 receptor-dependent phagocytosis and closely associated with the C3bi receptor.

Induction of granulocyte histaminase release by particle-bound complement C3 cleavage products (C3b, C3bi) and IgG

The interaction of opsonized particles with human granulocytes promotes a number of important biologic functions, including phagocytosis, superoxide generation, and release of a variety of enzymes, including histaminase. We have previously determined that histaminase release occurs via a C3-dependent process. Although fluid-phase C3b dimers can mediate release, the relative effects of particle-bound C3b and C3bi and of IgG have not been examined. In this report we demonstrate that particle-bound C3 deposited on activators of the alternative C pathway effected histaminase release in the absence of IgG. Particle-bound C3bi and C3b were both effective as mediators of histaminase release. The extent of release varied as a function of the activating surface on which C3 was deposited (zymosan C3b was considerably more potent than C3b bound to rabbit erythrocytes, which was slightly more potent than C3b bound to neuraminidase-treated sheep erythrocytes). In contrast, C3b or C3bi deposited on nonactivating surfaces (such as sheep erythrocytes) at inputs of up to 2,000,000 molecules per granulocyte failed to induce histaminase release unless IgG was also present. The ability of C3b bound to particles that serve as activators of the alternative pathway to induce histaminase release is apparently not the result of decreased susceptibility of C3b to proteolysis or to an increased binding affinity to the C3b receptor, but may relate to the interaction of other surface structures on activating particles with the PMN membrane.

Role of human factor I and C3b receptor in the cleavage of surface-bound C3bi molecules

Control of functions mediated by the third component of complement (C3) depends on the rate of generation and degradation of biologically active C3 fragments. To evaluate the mechanisms of degradation of active C3 fragments, the role of the control protein C3b/C4b inactivator (factor I) was investigated under conditions approximating those found in vivo, i.e. in the presence of plasma. The breakdown of human erythrocyte-bound C3bi molecules in serum or plasma was mediated only by factor I, since factor I-deficient or -depleted plasma was inactive until reconstituted with highly purified factor I. The rate of cleavage of C3bi bound to human erythrocytes by purified factor I was not affected by the presence or absence of beta 1H (factor H). The released breakdown product of C3bi has been shown to be C3c antigenically and on polyacrylamide gel electrophoresis in the presence of sodium dodecyl sulfate. Two different monospecific antibodies to the human C3b receptor totally abrogated factor I-mediated cleavage of cell-bound C3bi, suggesting that the C3b receptor (but not factor H) is required as an obligate cofactor. The rate of this C3b receptor-dependent, factor I-mediated cleavage of bound C3bi is strongly regulated by the surface to which C3bi is bound. Whereas C3bi bound to particulate nonactivators of the alternative complement pathway such as human erythrocytes is rapidly degraded by this mechanism, the rate of cleavage of C3bi bound to activators is significantly slower. These data suggest a physiologic role of C3b receptors in the degradation of biologically active C3 fragments deposited on host tissues. They also suggest that C3bi molecules on restricted surfaces are relatively stable and can thereby interact with complement C3 receptors in vivo.

Low ionic strength or chemical cross-linking of monomeric C3b increases its binding affinity to the human complement C3b receptor

Quantitative studies of the interaction between a fragment of the third component of complement (C3b) and its receptor on human cells have been undertaken with a recently developed radioligand binding assay. Specific binding of fluid phase monomeric C3b was direct and saturable under low (mu = 0.0513) but not physiological (mu = 0.15) ionic strength. Dimeric C3b had a greater affinity for the C3b receptor at either ionic strength. Complexing of monomeric C3b with another protein (human IgG) did not result in increase in binding to human erythrocytes when compared with monomeric C3b alone. These data suggest that ionic forces are involved in C3b receptor-ligand interactions and that the stable C3b-receptor binding site is present in monomeric C3b. Furthermore they suggest that the greater affinity of dimeric or oligomeric C3b is a result of multimeric binding to preclustered C3b receptors. These findings provide an explanation for the relatively stable interaction of particle bound C3b and C3b receptor-bearing cells in the immune adherence reaction.

Complement (C3b) interaction with the human granulocyte receptor: correlation of binding of fluid-phase radiolabeled ligand with histaminase release

The interaction of C3b, the major cleavage product of C3, with its receptor on human granulocytes results in important biological functions, including phagocytosis, superoxide generation, and release of a variety of enzymes, including histaminase. We have determined the binding kinetics and isotherm of trypsin-generated fluid-phase dimeric C3b at both 0 degrees C and 37 degrees C using human polymorphonuclear leukocytes (PMN). At 37 degrees C the apparent number of receptors per cell was threefold greater than number at 0 degrees C (66,000 vs 21,000), and the affinity (Ka) was slightly less (3.5 X 10(7) M-1 vs 6 x 10(7) M-1). C3b dimer binding was specifically inhibited by a F(ab,)2 anti-C3b receptor antibody. C3b dimer induced histaminase release in a dose-dependent fashion at a concentration of 1 to 4 X 10(7) molecules/cell, whereas at lower concentrations a dose-dependent inhibition of opsonized zymosan-induced release was noted. These effects were independent of IgG. In contrast, C3b monomer failed to demonstrate measurable direct binding or to induce histaminase release. Histaminase release, however, did occur after incubation of PMN with affinity-linked monomer (anti-C3 F(ab')2-C3b complexes). Monovalent complexes did not affect release. Monomeric C3, C3c, and C3d were without effect; however, affinity-linked C3 and C3c did cause release.

Complement (C3b) interaction with the human granulocyte receptor: correlation of binding of fluid-phase radiolabeled ligand with histaminase release

The interaction of C3b, the major cleavage product of C3, with its receptor on human granulocytes results in important biological functions, including phagocytosis, superoxide generation, and release of a variety of enzymes, including histaminase. We have determined the binding kinetics and isotherm of trypsin-generated fluid-phase dimeric C3b at both 0 degrees C and 37 degrees C using human polymorphonuclear leukocytes (PMN). At 37 degrees C the apparent number of receptors per cell was threefold greater than number at 0 degrees C (66,000 vs 21,000), and the affinity (Ka) was slightly less (3.5 X 10(7) M-1 vs 6 x 10(7) M-1). C3b dimer binding was specifically inhibited by a F(ab,)2 anti-C3b receptor antibody. C3b dimer induced histaminase release in a dose-dependent fashion at a concentration of 1 to 4 X 10(7) molecules/cell, whereas at lower concentrations a dose-dependent inhibition of opsonized zymosan-induced release was noted. These effects were independent of IgG. In contrast, C3b monomer failed to demonstrate measurable direct binding or to induce histaminase release. Histaminase release, however, did occur after incubation of PMN with affinity-linked monomer (anti-C3 F(ab')2-C3b complexes). Monovalent complexes did not affect release. Monomeric C3, C3c, and C3d were without effect; however, affinity-linked C3 and C3c did cause release.

Characterization of the human complement (c3b) receptor with a fluid phase C3b dimer

The interaction of C3b receptor with C3b, the major cleavage product of C3, elicits important biologic functions, such as enhanced phagocytosis and release of cellular enzymes. We determined the binding kinetics and binding isotherm of C3b-receptor interaction by using human cells and fluid phase C3b generated by trypsin cleavage of purified native C3. 125I labeled C3b was separated into 2 molecular species, a dimer and a monomer by column chromatography. We found that dimeric C3b bound to human erythrocyte C3b receptors with an affinity that was more than 25 times that of the monomer. 125I dimeric C3b did not bind to sheep red blood cells, which lack the C3b receptor, nor to trypsinized or 2-mercaptoethanol treated normal human red blood cells, 2 methods for abrogating the immune adherence activity. Binding of 125I fluid phase C3b dimer to the C3b receptor was specific, saturable (about 90 ng of C3b dimer bound maximally per 1 X 10(9) red blood cells), reversible (in the presence of a 100-fold molar excess of unlabeled ligand), and of moderate affinity (Kd about 9.53 nM). The equilibrium binding constants were similar with the various cells tested. Binding was characterized by rapid on and off rates and did not exhibit ligand cooperativity. This specific interaction reached a steady state within 10 to 15 min at 0 degrees C; 50% of specifically bound ligand dissociated from its binding site on human red blood cells in approximately 1 min at 0 degrees C. The density of C3b receptors on human red blood cells, polymorphonuclear leukocytes, monocytes, and B lymphocyte-enriched preparations was 360, 20,000, 30,000, and 21,000 receptors/cell, respectively.

Characterization of the human complement (c3b) receptor with a fluid phase C3b dimer

The interaction of C3b receptor with C3b, the major cleavage product of C3, elicits important biologic functions, such as enhanced phagocytosis and release of cellular enzymes. We determined the binding kinetics and binding isotherm of C3b-receptor interaction by using human cells and fluid phase C3b generated by trypsin cleavage of purified native C3. 125I labeled C3b was separated into 2 molecular species, a dimer and a monomer by column chromatography. We found that dimeric C3b bound to human erythrocyte C3b receptors with an affinity that was more than 25 times that of the monomer. 125I dimeric C3b did not bind to sheep red blood cells, which lack the C3b receptor, nor to trypsinized or 2-mercaptoethanol treated normal human red blood cells, 2 methods for abrogating the immune adherence activity. Binding of 125I fluid phase C3b dimer to the C3b receptor was specific, saturable (about 90 ng of C3b dimer bound maximally per 1 X 10(9) red blood cells), reversible (in the presence of a 100-fold molar excess of unlabeled ligand), and of moderate affinity (Kd about 9.53 nM). The equilibrium binding constants were similar with the various cells tested. Binding was characterized by rapid on and off rates and did not exhibit ligand cooperativity. This specific interaction reached a steady state within 10 to 15 min at 0 degrees C; 50% of specifically bound ligand dissociated from its binding site on human red blood cells in approximately 1 min at 0 degrees C. The density of C3b receptors on human red blood cells, polymorphonuclear leukocytes, monocytes, and B lymphocyte-enriched preparations was 360, 20,000, 30,000, and 21,000 receptors/cell, respectively.

Possible nonspecific immunopotentiation by 2,4-dinitrochlorobenzene sensitization in patients with Hodgkin's disease

Various immunological parameters were evaluated in untreated Hodgkin's patients before and after sensitization with dinitrochlorobenzene (DNCB). The ratio (r) of these parameters after/before DNCB sensitization for patients and second/first samples in the controls were calculated. There were significantly more patients in the r greater than 1.1 group for PHA and Con A responses and for peripheral blood T cell percentages. These data suggest that DNCB sensitization may have a nonspecific immunopotentiation effect.

Comparative analysis of systemic immunological parameters in ulcerative colitis and idiopathic proctitis: effects of sulfasalazine in vivo and in vitro

Comparative analysis of the systemic immunity revealed similarities between ulcerative colitis and idiopathic proctitis. In the active stage of both diseases, circulating complement receptor positive cells were increased whereas T-cell percentages and lymphocyte functions were decreased. In severe forms of ulcerative colitis and idiopathic proctitis circulating EAC-phagocytosing esterase positive cells, indicative of activated monocytes, were demonstrated. Successful treatment with salicylazosulfapyridine (SASP) reversed these immunological changes. Incubation of SASP and its metabolites with leucocytes from patients and control subjects, in concentrations similar to those demonstrated in sera from patients treated with SASP, did not alter the immunological changes.

Impairment of cell-mediated immunity in ectodermal dysplasia with aplastic anemia

A case of ectodermal dysplasia and aplastic anemia is presented in which a cell-mediated immunodeficiency led to a fatal Pneumocystis carinii infection. Elevated levels of IgG, IgA and IgD were present with normal specific antibody titres. A deficient cell-mediated immunity was documented by low T cell numbers, poor in vitro mitogenic responses, negative skin tests and by the histologic finding at autopsy of thymic dysplasia.

Possible effect of maternal promethazine therapy on neonatal immunologic functions

The effect of the administration of promethazine in the treatment of erythroblastosis fetalis was studied in four maternal-fetal pairs. The three infants exposed for a prolonged period of time had decreased neonatal number and function of T cells, and abnormal specific humoral immune responses. The possible role of promethazine in the induction of fetal immunoincompetence is discussed.

Choriocarcinoma as a cause of thyrotoxicosis

Three patients with choriocarcinoma had clinical and biochemical evidence of hyperthyroidism. Diminution in the thyrotoxicosis closely paralleled the fall in human chorionic gonadotrophin (hCG) levels. Three patients originally presented to internal medicine units as a problem of hemoptysis. Thyroid-stimulating hormone bioassay activity was demonstrated in the serum of all three patients prior to therapy. Recently evidence has been presented that hCG has intrinsic thyrotropic activity and that in conditions, such as hydatidiform mole, in which serum hCG levels are grossly elevated this thyrotropic activity can be sufficient to produce hyperthyroidism. Two of our cases supported the concept that hCG was also the substance with thyroid-stimulating activity in patients with choriocarcinoma. The third case left open the possibility that, in addition to the thyroid-stimulating activity of hCG, there may also be the production of a true ectopic thyroid-stimulating hormone (TSH). It is considered that the development of biochemical and clinical thyrotoxicosis in patients with choriocarcinoma depends upon the duration of the choriocarcinoma and the level of hCG.