Background Specific antibody deficiency may predispose patients to recurrent respiratory tract infections. There is limited literature assessing specific antibody deficiency in chronic rhinosinusitis (CRS). This study evaluated the role of specific antibody deficiency in patients with CRS who have failed medical therapy. Methods We performed a retrospective chart review of patients with CRS who underwent functional endoscopic sinus surgery and had prior assessment for humoral immunodeficiency. Each patient’s record was reviewed for serum quantitative immunoglobulin G (IgG) and IgA and anti–Streptococcus pneumoniae antibody titers measured at baseline and 6 weeks postvaccination with the 23-valent unconjugated pneumococcal vaccine. Clinical characteristics, including asthma, atopy, and nasal polyps, were recorded. Results Of the 129 CRS patients who met inclusion criteria, 93 (72%) had low baseline antipneumococcal titers. Fifteen (11.6%) patients were diagnosed with specific antibody deficiency based on an inadequate response to the pneumococcal polysaccharide vaccine. The group of patients with specific antibody deficiency had significantly lower serum IgA levels when compared with those patients with normal preimmunization titers (138 ± 67.3 versus 330 ± 356; p < 0.05). Patients with specific antibody deficiency had a significantly lower number of preimmunization protective antipneumococcal titers when compared with vaccine responders (1.41 versus 2.72; p < 0.0005). Conclusion This retrospective study indicates that patients with medically refractory CRS may have a high prevalence of low preimmunization antipneumococcal titers and specific antibody deficiency. Furthermore, lower serum IgA levels identified in these specific antibody deficiency patients suggests that a prospective study to further characterize this relationship is warranted.

Akt, when activated by IGF/insulin, can phosphorylate forkhead transcription factors. We undertook this study to determine whether epidermal growth factor (EGF) treatment could produce a signaling cascade resulting in phosphorylation of the forkhead transcription factor FKHR in a breast cancer cell line, MDA-MB-231. After establishing ErbB1, cbl, PI3 kinase and Akt were activated in EGF treated MDA-MB-231, we determined by immunoblot with FKHR antiserum that the electrophoretic mobility of FKHR was retarded after EGF treatment. This mobility retardation was reversible by treatment with alkaline phosphatase, and immunoblot with phospho-Ser 256 FKHR antibody further con®rmed phosphorylation on an Akt consensus site after EGF treatment. EGF stimulated FKHR phosphorylation was blocked by the PI3 kinase inhibitor LY294002, and the ErbB1 inhibitor AG1478. FKHR immunoblotting after puri®cation of nuclear and cytoplasmic proteins showed that EGF induced a simultaneous increase of FKHR in the cytoplasm and decrease in the nucleus. This ®nding was con®rmed by immuno¯uorescence staining. Treatment of cells with pharmacological inhibitors of PI3 kinase or ErbB1 blocked this e ect. Thus, these results demonstrate the phosphorylation and nuclear exclusion of FKHR after EGF treatment by a PI3 kinase dependent mechanism, and represent the ®rst report of growth factor regulation of endogenous FKHR localization Oncogene (2000) 19, 4574 ± 4581.

Epidermal growth factor receptor (EGFR) is widely expressed in a number of solid tumors including colorectal cancers. Overexpression of this receptor is one means by which a cell can achieve positive signals for survival and proliferation; another effective means is by constitutive activation of EGFR. We have elucidated the role of constitutive EGFR signaling in malignant progression by stably transfecting colon cancer cells with a human transforming growth factor-A cDNA (a ligand for EGFR) under repressible control by tetracycline. We show that constitutive expression of transforming growth factor-A and its subsequent constitutive activation of EGFR allows for cancer cell survival in response to environmental stress in vitro and in vivo as well. The reversal of constitutive EGFR activation results in the loss of downstream mitogenactivated protein kinase and Akt activation, and a reduction in xenograft size that is associated with decreased proliferation and increased apoptosis. We used CI-1033, a small molecule antagonist of EGFR, to dissect an activation pathway that shows the ability of ERBb2 to activate Akt, but not Erk in the face of EGFR antagonism. This novel escape mechanism is a possible explanation of why anti-EGFR therapies have shown disappointing results in clinical trials. [Cancer Res 2007;67(2):665-73]

Aberrant transcriptional regulation of transforming growth factor ␣ (TGF␣) appears to be an important contributor to the malignant phenotype and the growth factor independence with which malignancy is frequently associated. However, little is known about the molecular mechanisms responsible for dysregulation of TGF␣ expression in the malignant phenotype. In this paper, we report on TGF␣ promoter regulation in the highly malignant growth factor-independent cell line HCT116. The HCT116 cell line expresses TGF␣ and the epidermal growth factor receptor (EGFR) but is not growth inhibited by antibodies to EGFR or TGF␣. However, constitutive expression of TGF␣ antisense RNA in the HCT116 cell line resulted in the isolation of clones with markedly reduced TGF␣ mRNA and which were dependent on exogenous growth factors for proliferation. We hypothesized that if TGF␣ autocrine activation is the major stimulator of TGF␣ expression in this cell line, TGF␣ promoter activity should be reduced in the antisense TGF␣ clones in the absence of exogenous growth factor. This was the case. Moreover, transcriptional activation of the TGF␣ promoter was restored in an antisense-TGF␣-mRNA-expressing clone which had reverted to a growth factor-independent phenotype. Using this model system, we were able to identify a 25-bp element within the TGF␣ promoter which conferred TGF␣ autoregulation to the TGF␣ promoter in the HCT116 cell line. In the TGF␣-antisense-RNAexpressing clones, this element was activated by exogenous EGF. This 25-bp sequence contained no consensus sequences of known transcription factors so that the TGF␣ or EGF regulatory element within this 25-bp sequence represents a unique element. Further characterization of this 25-bp DNA sequence by deletion analysis revealed that regulation of TGF␣ promoter activity by this sequence is complex, as both repressors and activators bind in this region, but the overall expression of the activators is pivotal in determining the level of response to EGF or TGF␣ stimulation. The specific nuclear proteins binding to this region are also regulated in an autocrine-TGF␣-dependent fashion and by exogenous EGF in EGF-deprived TGF␣ antisense clone 33. This regulation is identical to that seen in the growth factor-dependent cell line FET, which requires exogenous EGF for optimal growth. Moreover, the time response of the stimulation of trans-acting factor binding by EGF suggests that the effect is directly due to growth factor and not mediated by changes in growth state. We conclude that this element appears to represent the major positive regulator of TGF␣ expression in the growth factor-independent HCT116 cell line and may represent the major site of transcriptional dysregulation of TGF␣ promoter activity in the growth factor-independent phenotype.

Home-based SCIG is safe and effective in elderly patients with PIDD, most of whom can self-infuse. Infection rates were low, and no AEs or difficulties in administering SCIG occurred that resulted in treatment discontinuation.