Suppressive effect of 3-methylcholanthrene on phagocytic activity of mouse peritoneal macrophages for Torulopsis glabrata.

The effect of 3-methylcholanthrene (MCA) on the phagocytic activity of mouse peritoneal macrophages for Torulopsis glabrata was investigated. Macrophages were maintained in glass scintillation vials or on cover slips in Leighton tubes with the use of Hanks' balanced salt solution plus 30% horse serum. Graded amounts of MCA were incorporated into the medium and the macrophages were parasitized with viable cells of T. glabrata. Macrophages from C3H mice, a strain highly susceptible to MCA carcinogenesis, were more prone to the suppressive effect of MCA than were the macrophages from CFW mice, a relatively resistant strain. Significant suppressive effect on phagocytosis of macrophages from C3H mice was observed with 5 micrograms MCA/ml, whereas up to 50 micrograms MCA/ml did not alter the phagocytic activity of CFW macrophages. However, 100 micrograms MCA/ml also suppressed the phagocytosis of CFW macrophages. Suppression in phagocytosis of C3H macrophages was observed after 6 hours' exposure to MCA, whereas a similar effect on CFW macrophages was seen after 12 hours. Treatment with 100 micrograms MCA/ml imparied the fungicidal activity of both C3H and CFW macrophages. These results indicate a correlation between the suppressive effect of MCA on macrophage activity and the strain susceptibility of mice to chemical carcinogenesis.

Presence of fucolipid antigens with mono- and dimeric X determinant (Lex) in the circulating immune complexes of patients with adenocarcinoma.

A series of fucosylated glycosphingolipids with the Lewisx (Lex) determinant (Gal beta 1----4[Fuc alpha 1----3]GlcNAc) have been shown to accumulate in human adenocarcinomas. Lex glycolipids were eluted from Protein A-silica columns over which plasma from patients with adenocarcinoma had previously been perfused. The fact that Protein A has strong affinity for IgG and IgG-immune complexes suggested that the Lex antigens isolated from Protein A eluates were complexed with IgG. Lewisx antigen eluted from Protein A columns banded in the immune complex-enriched region (below IgG) of neutral sucrose density gradients. A modified Raji cell assay and an anticomplement C1q enzyme-linked immunosorbent assay were also used for measurement of Lex antigen associated with C3- and C1q-CIC, respectively. Following affinity purification of Lex-IgG complexes and subsequent dissociation of these immune complexes, human antibodies were isolated which reacted with purified glycosphingolipids containing Lex. Levels of Lex-IgG complexes were found to be 2- to 5-fold higher in eluates of Protein A-silica columns perfused with plasma from adenocarcinoma patients compared to eluates from columns perfused with plasma from healthy individuals and patients with other cancers. These assays may prove to be of diagnostic and/or prognostic significance in adenocarcinoma.

An HPV-E6/E7 immunotherapy plus PD-1 checkpoint inhibition results in tumor regression and reduction in PD-L1 expression.

We have investigated if immunotherapy against human papilloma virus (HPV) using a viral gene delivery platform to immunize against HPV 16 genes E6 and E7 (Ad5 [E1-, E2b-]-E6/E7) combined with programmed death-ligand 1 (PD-1) blockade could increase therapeutic effect as compared to the vaccine alone. Ad5 [E1-, E2b-]-E6/E7 as a single agent induced HPV-E6/E7 cell-mediated immunity. Immunotherapy using Ad5 [E1-, E2b-]-E6/E7 resulted in clearance of small tumors and an overall survival benefit in mice with larger established tumors. When immunotherapy was combined with immune checkpoint blockade, an increased level of anti-tumor activity against large tumors was observed. Analysis of the tumor microenvironment in Ad5 [E1-, E2b-]-E6/E7 treated mice revealed elevated CD8(+) tumor infiltrating lymphocytes (TILs); however, we observed induction of suppressive mechanisms such as programmed death-ligand 1 (PD-L1) expression on tumor cells and an increase in PD-1(+) TILs. When Ad5 [E1-, E2b-]-E6/E7 immunotherapy was combined with anti-PD-1 antibody, we observed CD8(+) TILs at the same level but a reduction in tumor PD-L1 expression on tumor cells and reduced PD-1(+) TILs providing a mechanism by which combination therapy favors a tumor clearance state and a rationale for pairing antigen-specific vaccines with checkpoint inhibitors in future clinical trials.

Use of protein A immunoadsorption as a treatment for thrombocytopenia in HIV-infected homosexual men: a retrospective evaluation of 37 cases.

Thirty-seven HIV-infected homosexual men with thrombocytopenia (less than 100 x 10(9)/l) received protein A immunoadsorption treatments to remove platelet-sensitizing immunoglobulin (Ig) G and circulating immune complexes (CIC) from plasma. Patients received an average of six treatments each, consisting of 250 ml plasma over a 3-week period. Clinical improvement in hemorrhagic symptoms associated with substantial increase in platelet counts was achieved in 18 patients. These responses were maintained over a median follow-up period of more than 7 months in 14 evaluable patients who were not lost to follow-up (three patients relapsed in 2 weeks and one received another therapy). Generally, moderate transient treatment-related side-effects included fever, musculoskeletal pain, chills and nausea. A transient serum sickness-like reaction was observed in seven patients, leading to termination of treatment in two. Clinical responses were associated with significant decreases in levels of platelet-sensitizing Ig, including CIC. Stimulation of broadly cross-reactive anti-antigen-binding fragment [F(ab)2], antibodies contributed to these responses. Protein A immunoadsorption is an effective alternative treatment for HIV-associated thrombocytopenia.

Modulation of immunity in patients with autoimmune disease and cancer treated by extracorporeal immunoadsorption with PROSORBA columns.

Extensive animal studies and clinical observations support an immunosuppressive role for certain antibodies and circulating immune complexes (CIC) in malignant and autoimmune diseases. Investigators have attempted to correct or modulate dysfunction by removal of antibodies or CIC from plasma. Extra-corporeal immunoadsorption of plasma over columns containing a silica matrix and covalently attached highly purified staphylococcal protein A (PROSORBA column) is a procedure that specifically removes those plasma components by the interaction of protein A with the Fc region of IgG. The interaction of CIC with the Fc receptor on protein A has three specific results. First, there is direct removal of immunosuppressive CIC from the circulation. Studies of CIC-mediated immunosuppression in experimental systems have shown dose-response relationships over wide ranges of CIC concentrations. Thus, removal of CIC relative to the IgG antibody may be expected to exert some stimulation of the immune system. Second, the complement system is activated. Elevated levels of C3a, C4a, and C5a are observed in patients' circulating plasma after PROSORBA treatment. These levels peak one to three hours post-perfusion and are near normal levels by six hours post-perfusion. These complement components are stimulators of growth and activity of immune cells. In addition, by binding to CIC they stimulate clearance of CIC by the reticuloendothelial system. Thus, treatments may induce removal of more CIC than could be anticipated by the binding capacity of treatment columns. Third, antibody is released from CIC. Interaction of CIC with bound protein A with or without the aid of activated complement components leads to liberation of free antibody. Depending upon other factors, eg, amount of circulating antigen and/or unbound IgG, either free antibody or CIC containing more antibody relative to antigen (or both) may be infused into patients with the posttreatment plasma. Such CIC function as immune stimulators rather than suppressors of immune cell activity. The consequences of the treatments are summarized as follows. Stimulation of immune cellular activity is seen one to three hours posttreatment. During the first one to three treatments, cells of the granulocyte/macrophage series show the greatest increase. During and after treatments 2 to 4, lymphocytes show the greatest increase. At this point, increased blastogenic response to mitogens is observed along with an increase in the T helper/suppressor cell ratio.(ABSTRACT TRUNCATED AT 400 WORDS)

Selective removal of antigen-complexed IgG from cat plasma by adsorption onto a protein A-silica matrix.

The binding of normal cat IgG, heat-aggregated cat IgG and specific immune complexes (IC) containing cat IgG to a silica matrix containing covalently bound Staphylococcus aureus protein A was evaluated. The amounts of serum relative to protein A-silica, the flow rates and the perfusion times were representative of those existing when protein A-silica columns are used for therapeutic extracorporeal immunoadsorption of IgG and IC from humans and animals. When cat IgG was present in a large excess, approximately one molecule was bound to the matrix per molecule of solid-phase protein A with a KA of 1.5 X 10(6) 1/mol. Aggregated and immune complexed IgG bound to the matrix with relatively higher affinity. IC prepared in vitro between the purified envelope glycoprotein of the feline leukemia virus (FeLV gp70) and affinity-purified cat antibodies bound to the matrix even though normal IgG was present in greater than 10,000-fold excess. Once bound, IC were not eluted from columns upon further perfusion with normal serum. However, bound IgG was eluted from columns by further perfusion of normal serum or IC. IC were at least five-fold more efficient than normal IgG in exerting this effect. The results suggest that protein A-silica columns can be used for preferential removal of IC from plasma in a clinical or experimental setting.

Presenting symptoms and diagnostic lag in children with inflammatory bowel disease.

Presenting symptoms and their duration may affect the time that elapses prior to definitive diagnosis of inflammatory bowel disease (IBD). This study was undertaken to determine the mean duration of presenting symptoms and diagnostic lag in children with IBD. The medical records of all patients less than 19 years of age diagnosed with IBD at the pediatric gastroenterology clinic of Children's Hospital of Wisconsin between 1990-1995 were reviewed. The age at diagnosis, gender, presenting symptoms and duration, disease location, and diagnostic lag were analyzed. There were 91 children (49 male) diagnosed with IBD. Crohn's disease (CD) was diagnosed in 58, ulcerative colitis (UC) in 24, and indeterminate colitis in 9. The mean ages at diagnosis were 11.4 years for CD, 9.7 years for UC, and 7.8 years for indeterminate colitis. The most frequent presenting symptoms were abdominal pain, diarrhea, hematochezia, and weight loss. The average lag in diagnosis of CD was 7.1 months, which varied by disease location: small intestine 10.5 months, ileocolonic 7.5 months, and colonic 6.4 months. The average lag in diagnosis was 6.7 months for UC and 14 months for indeterminate colitis. Children presenting with growth failure had the longest diagnostic lag. (a) The elapsed time between symptom onset and the diagnosis of CD has decreased. (b) The diagnostic lag in CD decreases with distal colonic involvement. (c) Following onset of symptoms UC was diagnosed only slightly more rapidly than CD.

Physical findings in nutritional deficiencies.

Manifestations of deficiencies of protein, calories, vitamins, and trace elements are described. These findings are placed in the context of the functions, food sources, and causes of deficiency of each micronutrient.

Cyclic vomiting syndrome: evolution in our understanding of a brain-gut disorder.

Cyclic vomiting syndrome (CVS) remains a mysterious disorder despite our increasing knowledge since its classic description by Gee in 1882. Its hallmark feature of recurrent, explosive bouts of vomiting punctuating periods of normal health causes substantial medical morbidity (50% of patients require intravenous therapy), as well as significant time lost from school (20 school absences per year) and work. Limited epidemiologic data indicate that CVS may occur more commonly than previously thought, affecting as many as 1.9% of school-aged children. Besides the relentless vomiting, the child usually has pallor (87%), lethargy (91%), anorexia (74%), nausea (72%), and abdominal pain (80%). There is evidence of clinical and physiologic overlap among CVS, abdominal migraine, and migraine headaches. We propose revised criteria for abdominal migraine that include pain as the predominant and consistent symptom, lack of abnormal screening tests, and in retrospect, either subsequent development of migraines or positive response to antimigraine medication. Besides migraines, other etiologic possibilities include mitochondrial DNA mutations, ion channelopathies, excessive hypothalamic-pituitary-adrenal axis activation, and heightened autonomic reactivity. The differential diagnosis includes idiopathic CVS (88%); gastrointestinal disorders (7%), including serious surgical disorders (e.g., malrotation); and extraintestinal disorders (5%), including serious surgical (brain stem neoplasm) and metabolic disorders (e.g., fatty acid oxidation disorder). Within the idiopathic group, there may be migraine, Sato's neuroendocrine, mitochondrial, and other subgroups. Treatment includes avoidance of triggers, prophylactic medication, supportive care, abortive medication, and family support. In the future, investigation into mitochondrial DNA mutations, ion channel defects, corticotropin-releasing factor, and serotonin and tachykinin receptor physiology and pharmacology may help discover the etiology and pathogenesis of this disorder.

A non-oncogenic HPV 16 E6/E7 vaccine enhances treatment of HPV expressing tumors.

Human papillomaviruses (HPVs) are the causative factor for >90% of cervical cancers and 25% of head and neck cancers. The incidence of HPV positive (+) head and neck squamous cell carcinomas has greatly increased in the last 30 years. E6 and E7 are the two key viral oncoproteins that induce and propagate cellular transformation. An immune response generated during cisplatin/radiation therapy improves tumor clearance of HPV(+) cancers. Augmenting this induced response during therapy with an adenoviral HPV16 E6/E7 vaccine improves long-term survival in pre-clinical models. Here, we describe the generation of an HPV16 E6/E7 construct, which contains mutations that render E6/E7 non-oncogenic, while preserving antigenicity. These mutations do not allow E6/E7 to degrade p53, pRb, PTPN13, or activate telomerase. Non-oncogenic E6/E7 (E6(Δ)/E7(Δ)) expressed as a stable integrant, or in the [E1-, E2b-] adenovirus, lacks the ability to transform human cells while retaining the ability to induce an HPV-specific immune response. Moreover, E6(Δ)/E7(Δ) plus chemotherapy/radiation statistically enhances clearance of established HPV(+) cancer in vivo.