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T A Hamilton

Publications and source records attributed to T A Hamilton.

At least 73 records · Page 4Linked to original sources
PubMed1995

Sulfasalazine therapy for psoriatic arthritis: a double blind, placebo controlled trial.

OBJECTIVE: Psoriatic arthritis (PsA) is often poorly responsive to 2nd line antirheumatic drug therapy. Sulfasalazine has recently gained wide acceptance in the treatment of rheumatoid arthritis, and beneficial effects have also been noted in ankylosing spondylitis and reactive arthritis. We report a double blind placebo controlled study of sulfasalazine in PsA. METHODS: Twenty-four patients with active PsA were randomized to receive either sulfasalazine (3 g/day) (n = 10) or placebo (n = 14) for 8 weeks, in a double blind manner, followed by an 8 week open label crossover phase for nonresponding placebo patients. RESULTS: Compared with placebo controls, sulfasalazine treated patients were significantly improved at Weeks 4 and 8 with respect to physician (p < 0.01) and patient (p < 0.05) global assessments. Duration of morning stiffness was significantly decreased at Week 8 (p < 0.01). Clinical variables of disease activity returned to baseline after a 4 week drug washout period in 5 evaluable patients. Six patients in the placebo group crossed over to an 8 week open label phase and demonstrated significant improvements in joint scores, 50 ft walking time, and global patient assessment. Sulfasalazine treated patients also showed significant improvements in cutaneous involvement. CONCLUSION: Sulfasalazine was effective in PsA, with efficacy observed as early as the 4th week of treatment. Longterm studies are needed to determine whether such therapy can modify disease outcome.

Activities of Daily Living↗
PubMed1994

Murine inhibitory protein-kappa B alpha negatively regulates kappa B-dependent transcription in lipopolysaccharide-stimulated RAW 264.7 macrophages.

The potential role of the inhibitory protein (I)-kappa B alpha gene in control of LPS-dependent transcription has been investigated in the murine macrophage cell line RAW 264.7. LPS-induced transcription in macrophages is believed to involve activation of members of the Rel homology family of transcription factors, and may be negatively regulated by cytoplasmic inhibitor proteins collectively termed I-kappa Bs. To evaluate the role of I-kappa Bs in LPS-stimulated macrophages, murine I-kappa B alpha (ml-kappa B alpha) has been expressed as a glutathione-S-transferase (GST) fusion protein and examined for its ability to control kappa B binding activities in nuclear extracts from LPS-treated RAW 264.7 macrophages. ml-kappa B alpha-GST inhibited LPS-induced kappa B binding activity from RAW 264.7 cells in a phosphorylation-dependent fashion, but did not affect IFN-alpha-induced IFN stimulus response element binding. Recombinant I-kappa B alpha inhibited kappa B motif binding by nuclear factor-kappa B1, RelA, and c-Rel as indicated by studies using UV radiation-induced covalent cross-linking to a bromodeoxyuridine-substituted kappa B oligonucleotide. Transfection of macrophages with an expression vector encoding ml-kappa B alpha inhibited LPS-stimulated transcription driven by a 243-bp promoter sequence obtained from the 5' flanking region of the murine IP-10 gene. This promoter sequence contains two kappa B motifs that have been shown to be critical to LPS-dependent reporter gene transcription. The kappa B sites seem to be the specific target of I-kappa B alpha function, as reporter gene transcription driven by these motifs in the context of a heterologous thymidine-kinase promoter (TK) also was inhibited by co-transfection with ml-kappa B alpha. These observations indicate that ml-kappa B alpha is capable of controlling kappa B-dependent transcription in LPS-stimulated murine macrophages.

Animals↗
PubMed1994

T cells from renal cell carcinoma patients exhibit an abnormal pattern of kappa B-specific DNA-binding activity: a preliminary report.

Recent data suggest that the poor induction of a T-cell response to human renal cell carcinoma (RCC) may be related to alterations in signal transduction pathways. We report that T cells from RCC patients have two alterations in kappa B motif-specific DNA-binding activity. The first alteration involves the constitutive expression of substantial kappa B-binding activity in nuclear extracts, which was observed in the electrophoretic mobility shift assay. The magnitude of kappa B activity in unstimulated patient T cells was similar to that observed in T cells from normal individuals that had been activated in vitro. On the basis of Western blotting experiments using antibodies to kappa B/Rel family proteins, the kappa B-binding activity constitutively expressed in T cells from RCC patients is composed mostly of the NF-kappa B1 (p50) subunit. The second abnormality in kappa B-binding activity in T cells from these patients is that RelA, a member of the Rel homology family which is part of the normal NF-kappa B complex, was not induced in the nucleus following activation. Western blotting analysis did not detect any RelA in nuclear extracts either before or after stimulation of T cells. The altered kappa B-binding activity in T cells from RCC patients may impair their capacity to respond normally to various stimuli.

Base Sequence↗
PubMed1994

Endotoxin-induced early gene expression in C3H/HeJ (Lpsd) macrophages.

C3H/HeJ (Lpsd) macrophages have been shown to respond to certain LPSs, especially from rough mutant bacteria. C3H/OuJ (Lpsn) macrophages are induced by wild-type LPS, rough LPS, or lipid A to express many genes, including TNF-alpha, TNFR-2, IL-1 beta, IP-10, D3, and D8. C3H/HeJ macrophages failed to induce any of these genes when cultured with wild-type LPS or synthetic lipid A, even when pretreated with IFN-gamma. However, rough mutant Salmonella minnesota Ra, Rc, and Rd LPS, and Escherichia coli D31 m3 Rd LPS induced Lpsd macrophages to express a subset of genes within the gene panel. Because bioactive preparations contained trace quantities of endotoxin protein(s), a deoxycholate-modified, phenol-water method was used to repurify rough LPS into an aqueous phase, and extract endotoxin proteins into a phenol phase. Repurified LPS failed to stimulate Lpsd macrophages; however, phenol fractions were approximately 10% as potent in Lpsd macrophages as crude rough LPS. Full potency was restored in C3H/HeJ macrophages when aqueous phase LPS and phenol-phase proteins were co-precipitated, suggesting that LPS and endotoxin proteins interact synergistically. Endotoxin proteins alone induced TNF-alpha, TNFR-2, and IL-1 beta, but not IP-10, D3, and D8 genes in both Lpsd and Lpsn macrophages. Tyrosine phosphorylation of three 41- to 47-kDa proteins was induced by endotoxin proteins, but not by LPS, in Lpsd macrophages. Thus, endotoxin proteins seem to activate a signaling pathway(s) that converges (distal to the Lps gene product) with a subset of LPS-signaling pathways.

Animals↗
PubMed1994

Mechanisms of IL-4-mediated suppression of IP-10 gene expression in murine macrophages.

The mechanisms involved in negative regulation of IFN-gamma-induced IP-10 mRNA expression by IL-4 have been examined in an immortalized murine macrophage cell line (ANA-1). As in primary peritoneal macrophages, IL-4 selectively inhibits the production of IP-10 mRNA by IFN-gamma-treated ANA-1 cells. Expression of another IFN-gamma-inducible gene (D3) was not affected by co-treatment with IL-4. Suppression of IFN-gamma-induced IP-10 mRNA expression by IL-4 is mediated at the level of transcription. IFN-gamma-induced transcription of CAT expression driven by a 243-bp IP-10 promoter fragment was also sensitive to the suppressive effects of IL-4. In contrast, LPS-induced CAT expression was unaffected under identical experimental conditions. The positive transcriptional response to IFN-gamma required an interferon stimulus response element (ISRE) sequence motif located approximately 230 bp upstream from the transcription start site of the IP-10 gene. That this site is the target of the suppressive action of IL-4 is indicated by the ability of IL-4 to inhibit IFN-gamma-mediated transcription from this ISRE sequence in the context of a heterologous promoter. Finally, both IFN-gamma and IL-4 can enhance or induce expression of distinct nuclear factors that exhibit ISRE-specific binding activity. IL-4 does not suppress the IFN-gamma-induced ISRE binding activity. Together, these findings demonstrate that IL-4 inhibits IP-10 mRNA production in murine macrophages by suppressing the formation of new transcripts. Both positive and negative transcriptional activity appears dependent on activation of factors that recognize the ISRE.

Animals↗
PubMed1994

IFN-gamma selectively inhibits lipopolysaccharide-inducible JE/monocyte chemoattractant protein-1 and KC/GRO/melanoma growth-stimulating activity gene expression in mouse peritoneal macrophages.

IFN-gamma and LPS have both been shown to stimulate enhanced chemoattractant cytokine gene expression in mononuclear phagocytes. In this report, IFN-gamma was found to suppress LPS-induced chemokine mRNA expression in a cell type- and gene-specific fashion. Expression of JE (monocyte chemoattractant protein-1) and KC (GRO/melanoma growth-stimulating activity) mRNA in macrophages stimulated with LPS was markedly suppressed by IFN-gamma in a dose- and time-dependent fashion. LPS-induced IP-10 mRNA was unaffected by IFN-gamma under identical experimental conditions. This effect was cell type-specific because JE and KC mRNA expression in LPS-stimulated murine endothelial cells, TNF-alpha-stimulated endothelial cells, and NIH-3T3 cells were unaffected by IFN-gamma. The IFN-gamma-mediated suppression of LPS-stimulated KC mRNA expression was independent of protein synthesis and mediated at the transcriptional level. These observations indicate that IFN-gamma may function as a negative regulatory signal for the expression of some proinflammatory cytokines in macrophages. The cell type-dependent differential behavior of individual members of the chemokine family may be an important determinant of the cellular composition and outcome of an inflammatory response.

Animals↗
PubMed1994

Kappa B binding activity in a murine macrophage-like cell line. Sequence-specific differences in kappa B binding and transcriptional activation functions.

The role of two distinct kappa B sequence motifs found in the promotor of the murine IP-10 gene was studied in the transcriptional response of macrophages to lipopolysaccharides (LPS). When the murine macrophage cell line RAW 264.7 was stimulated with LPS, at least three different kappa B sequence-specific complex-forming activities were observed in nuclear extracts as assayed by electrophoretic mobility shift assay (EMSA). These three complexes were distinguished from one another in terms of time of appearance following stimulation and selectivity for one of the two different kappa B sequence motifs. The participation of individual members of the Rel homology family of kappa B sequence binding factors was assessed by use of specific antibodies in combination with either EMSA or UV-cross-linking to radiolabeled, BrdUrd-substituted oligonucleotide probes. The C1 complex contained predominantly NF kappa B1 (p50). The C2 complex contained NF kappa B1, RelA (p65), and perhaps other factors. The C3 complex contained predominantly c-Rel. Both kappa B sequences were able to mediate reporter gene transcription in LPS-stimulated macrophages, but the sites behaved differentially in cells co-transfected with expression vectors encoding different members of the Rel homology family. The results indicate that LPS activates several different forms of kappa B binding activity in murine macrophages which are composed of at least three different members of the Rel homology family. These binding activities exhibit differential recognition of and functional activation through the two distinct kappa B sequence motifs.

Animals↗
PubMed1994

Esophageal plasmacytoma in a dog.

A 14-year-old spayed female dog of mixed breeding had a 3-week history of regurgitation of food occasionally mixed with blood. An esophagram revealed a mass in the caudal portion of the esophagus. The mass was partially removed through esophagoscopy. Evaluation of light microscopy, immunoperoxidase technique, and electron microscopy was consistent with an esophageal plasmacytoma. Surgical excision of the esophageal plasmacytoma was performed. Dogs with esophageal plasmacytoma appear to have a good prognosis.

Animals↗
PubMed1994

Cell type and stimulus specific regulation of chemokine gene expression.

The pattern of chemoattractant cytokine gene (IP-10, JE, KC) expression has been examined in BALB/c 3T3 fibroblasts and MC3T3-E1 osteoblasts in response to a variety of different inflammatory stimuli, including IFN gamma, TNF alpha, IL-1 alpha, and IL-6. Both cell types expressed JE and IP-10 mRNAs but the response pattern varied in a stimulus- and gene-dependent fashion. KC mRNA was only expressed in BALB/c 3T3 cells stimulated by IL-1 alpha. The time dependence for expression was distinctive for each gene but was comparable despite different forms of stimulation. Nevertheless, the mechanisms involved in the induction of each gene varied with the stimulus and involved both transcriptional and post-transcriptional components. These findings reflect the diversity of chemokine gene expression in vivo and may be important in mechanistic understanding of the diversity of inflammatory response patterns.

3T3 Cells↗
PubMed1994

Chemokine expression in trinitrochlorobenzene-mediated contact hypersensitivity.

The expression of the murine IP-10 and MCP-1 genes has been examined in the skin of mice during contact hypersensitivity reactions to the hapten trinitrochlorobenezene (TNCB). In both naive and passively sensitized animals, challenge with TNCB resulted in elevated expression of both genes as early as 4 h as detected by Northern hybridization analysis. Twenty-four hours after challenge, expression was markedly reduced in naive animals but remained elevated in sensitized animals. This prolonged expression of chemokine gene products correlates with the tissue swelling response generally used as a measure of delayed-type hypersensitivity (DTH) in this model and suggests that the continued expression of these genes results from the stimulation of hapten-specific T helper cells. Examination of cell type expression patterns by in situ hybridization using 3H-radiolabeled riboprobes confirmed the results of Northern hybridization experiments. Both genes were expressed predominantly in cells exhibiting the morphology of connective tissue fibroblasts, although the distribution of cells positive for IP-10 mRNA expression differed from that of cells expressing MCP-1 mRNA. IP-10 expression was localized almost exclusively to a population of connective tissue cells surrounding the fur follicle. MCP-1 expression was rarely found associated with fur follicles but instead was distributed throughout the dermis in cells embedded in the collagenous extracellular matrix. Surprisingly, neither endothelial cells lining the small vessels located deep within the dermis nor epidermal keratinocytes were positive under any of the conditions utilized in the present study. Expression of both IP-10 and MCP-1 has been previously reported in a variety of distinct cell types in vitro. The present results indicate that only a subset of the cell types with such potential are stimulated to express these chemokine genes in vivo during hapten-mediated DTH responses, implying the presence of subtle cell type- and tissue-specific control mechanisms.

Animals↗
PubMed1994

Okadaic acid stimulates inflammatory cytokine gene transcription in murine peritoneal macrophages.

The involvement of protein phosphorylation in controlling proinflammatory cytokine gene expression by mononuclear phagocytes has been examined using okadaic acid (OA), a specific inhibitor of protein phosphatases 1 and 2A. OA (100 nM) was able to stimulate accumulation of TNF alpha and IP-10 mRNAs in thioglycollate-elicited peritoneal macrophages from C57B1/6 mice. The responses to OA or LPS were similar in several respects. The OA- and LPS-stimulated increases in IP-10 and TNF alpha mRNA were mediated through increases in the transcriptional activity of the genes as measured by nuclear run-on analysis. Both OA- and LPS-stimulated mRNA accumulation were independent of protein synthesis. Furthermore, OA and LPS resulted in elevated kappa B binding activity in treated macrophages which coincided temporally with the increased transcriptional activity of the two cytokine genes. The polypeptide composition of kappa B motif binding complexes from LPS- or OA-treated macrophages was similar. However, OA-induced expression of the TNF alpha and IP-10 genes was markedly delayed (detectable expression was only seen at 4-8 hr after stimulation) relative to that seen in LPS-stimulated macrophages in which both transcription and accumulation of mRNA can be seen within 30 min to 1 hr. Furthermore, the combination of LPS and OA had differential effects on TNF alpha and IP-10 mRNA levels; TNF alpha mRNA expression was prolonged in cells stimulated with LPS plus OA as compared to cells treated with LPS alone. This difference was the result of an increase in the half-life of cytoplasmic TNF alpha mRNA. No similar effect was seen on IP-10 mRNA stability. Thus, although protein phosphorylation appears to be important in regulating cytokine mRNA levels, OA and LPS most likely function via at least partially distinct cellular mechanisms.

Animals↗
PubMed1994

Regulation of macrophage gene expression by T-cell-derived lymphokines.

Cytokines secreted from antigen-specific T lymphocytes provide important positive and negative control of inflammation through their effects on non-antigen-specific inflammatory leukocytes. These effects often involve modulation of gene expression. Lymphokine-inducible macrophage gene expression is largely controlled at the level of transcription. Multiple cis-acting sequence motifs cooperate with one another to produce patterns of expression that are relatively unique to individual genes. Members of trans-acting transcription factor families, which recognize related regulatory sequence elements, participate frequently in complex protein-protein interactions that generate remarkable complexity in terms of the number of potential combinations and the consequential functional differences exhibited by each combination. Thus, the remarkable plasticity of immune-mediated inflammation derives from combinations of finite numbers of options at several points in the cellular and molecular sequence.

Animals↗
PubMed1994

Topical tretinoin (retinoic acid) treatment of hyperpigmented lesions associated with photoaging in Chinese and Japanese patients: a vehicle-controlled trial.

BACKGROUND: Hyperpigmented lesions are a predominant component of photoaging in Chinese and Japanese persons. Topical 0.1% tretinoin cream improves the hyperpigmentation associated with photoaging in Caucasian persons. OBJECTIVE: Our purpose was to assess the efficacy of 0.1% tretinoin cream treatment of hyperpigmented lesions associated with photoaging in Chinese and Japanese patients. METHODS: Forty-five photoaged patients (23 Chinese, 22 Japanese) completed a double-blind, randomized study in which 21 applied 0.1% tretinoin cream and 24 applied vehicle cream once daily to face and/or hands for 40 weeks. Patients' hyperpigmented lesions were evaluated clinically and by colorimetry throughout the study and by histologic analysis of skin biopsy specimens taken before therapy and at the end of treatment. RESULTS: At the end of treatment, hyperpigmented lesions of the face and hands were lighter or much lighter in 90% of patients receiving tretinoin compared with 33% receiving vehicle (p < 0.0001). Colorimetry demonstrated significant lightening of lesions after tretinoin compared with vehicle (p < 0.05). Histologic analysis of hyperpigmented lesions demonstrated a statistically significant 41% decrease in epidermal pigmentation with tretinoin therapy as compared with a 37% increase in the vehicle group (p = 0.0004). No patient withdrew for adverse effects. CONCLUSION: By clinical, colorimetric, and histologic evaluation, 0.1% tretinoin cream significantly lightens the hyperpigmentation of photoaging in Chinese and Japanese patients.

Administration, Topical↗
PubMed1994

A prospective study of renal structure and function in psoriasis patients treated with cyclosporin.

The impact of long-term cyclosporin therapy on kidney structure and function was evaluated in psoriasis patients with normal baseline renal function. Patients received cyclosporin at an average dose 3.9 mg/kg/day for up to three years and underwent serial kidney biopsies and measurements of iothalamate clearance and serum creatinine concentration. Kidney biopsy specimens (assessed on a scale of 0 to 4 where 0 = normal and 4 = severe) from 19 cyclosporin-treated patients as compared to 38 age-matched transplant donors showed increased interstitial fibrosis (1.9 +/- 0.2 vs. 0.3 +/- 0.1, P < 0.0001) and tubular atrophy (1.6 +/- 0.2 vs. 0.3 +/- 0.1, P < 0.0001) at one year. Eleven patients had a second biopsy after an additional two years of cyclosporin treatment demonstrating additional interstitial fibrosis (1.8 +/- 0.2 to 2.4 +/- 0.3, P = 0.002) and tubular atrophy (1.4 +/- 0.2 to 1.9 +/- 0.2, P = 0.053), and the onset of cyclosporin-associated arteriolopathy (0 to 0.5 +/- 0.2, P = 0.02). Quantitative digital morphometric analysis of trichrome-stained specimens also showed increased interstitial fibrosis (22.5 +/- 1.5 to 32.0 +/- 2.0% of interstitial area, P = 0.0008). Iothalamate clearance declined at an average rate of -3.1 ml/min/1.73 m2 per year (95% CI -5.8, -0.3) during the period of cyclosporin treatment. The slope of reciprocal serum creatinine declined by -0.06 dl/mg per year (95% CI -0.08, -0.04). Chronic cyclosporin treatment of otherwise healthy psoriasis patients is associated with progressive renal structural injury and reduced glomerular filtration rate.

Adult↗
PubMed1994

Topical retinoic acid (tretinoin) for melasma in black patients. A vehicle-controlled clinical trial.

BACKGROUND AND DESIGN: Melasma is an acquired, masklike, facial hyperpigmentation. The pathogenesis and treatment of melasma in black (African-American) patients is poorly understood. We investigated the efficacy of topical 0.1% all-trans-retinoic acid (tretinoin) in the treatment of melasma in black patients. Twenty-eight of 30 black patients with melasma completed a 10-month, randomized, vehicle-controlled clinical trial in which they applied either 0.1% tretinoin or vehicle cream daily to the entire face. They were evaluated clinically (using our Melasma Area and Severity Index), colorimetrically, and histologically. RESULTS: After 40 weeks, there was a 32% improvement in the Melasma Area and Severity Index score in the tretinoin treatment group compared with a 10% improvement in the vehicle group. Colorimetric measurements showed lightening of melasma after 40 weeks of tretinoin treatment vs vehicle. Lightening of melasma, as determined clinically, correlated well with colorimetric measurements. Histologic examination of involved skin revealed a significant decrease in epidermal pigmentation in the tretinoin group compared with the vehicle group. Side effects were limited to a mild "retinoid dermatitis" occurring in 67% of tretinoin-treated patients. Among the patients in this study in comparison with comparably recruited white patients, melasma was reported to have begun at a later age and was more likely to be in a malar distribution. CONCLUSIONS: This controlled study demonstrates that topical 0.1% tretinoin lightens melasma in black patients, with only mild side effects.

Adult↗
PubMed1994

Clinical improvement following dermabrasion of photoaged skin correlates with synthesis of collagen I.

BACKGROUND AND DESIGN: The ability of superficial dermabrasion to improve clinical features of photoaged skin is well known, but the specific biological mechanisms involved are poorly understood. The so-called repair zone, as visualized by routine histologic examination, has been attributed to new collagen formation within the papillary dermis and may be responsible for clinical improvement following dermabrasion. We investigated molecular and histologic events occurring in dermabraded skin and correlated them with clinical improvement. Ten photoaged patients (mean age, 59 years) underwent facial dermabrasion to the level of the papillary dermis. Clinical severity of photoaging was graded in a blinded manner at baseline and 12 weeks after dermabrasion. Biopsy specimens obtained at baseline and 3 and 12 weeks after dermabrasion were analyzed histologically and by in situ hybridization for fibroblast procollagen I mRNA, immunohistologically and by Western blotting with a monoclonal antibody specific for the aminoterminal cleavage site of procollagen I. RESULTS: Masson's trichrome staining demonstrated an increase in collagen from baseline (as an upper dermal band in the dermabrasion "repair zone") at 3 and 12 weeks' postdermabrasion. Immunohistologic examination demonstrated papillary dermal fibroblast staining for procollagen I at baseline that increased by threefold at 3 weeks' postdermabrasion and by 1.5-fold at 12 weeks' postdermabrasion. Western blotting demonstrated an average-fold increase in pN collagen I of 4.2 +/- 1.5 at 3 weeks and of 2.7 +/- 0.7 at 12 weeks. By in situ hybridization, baseline levels of procollagen I mRNA in papillary dermal fibroblasts increased sixfold at weeks 3 and 12 postdermabrasion. Increase in procollagen I mRNA correlated with clinical improvement, ie, reduction in wrinkling. CONCLUSION: Superficial dermabrasion clinically improves photoaged skin, and this improvement correlates strongly with increased collagen I gene expression.

Aged↗
PubMed1994

Chemokine gene expression in the murine renal cell carcinoma, RENCA, following treatment in vivo with interferon-alpha and interleukin-2.

The expression of three chemoattractant cytokine (chemokine) messenger (m)RNAs in the murine renal cell carcinoma (RENCA) from mice treated with a combination of interferon-alpha (IFN-alpha) and interleukin-2 was examined and related to tumor infiltration by inflammatory leukocytes. Using a semi-quantitative reverse transcriptase polymerase chain reaction assay, mRNAs encoding the KC, JE, and IP-10 genes were all elevated in tumor tissue from mice treated systemically with IFN-alpha/interleukin-2 for 4 days. Similarly, the mRNA for tumor necrosis factor-alpha (TNF-alpha) was also increased in tumors from treated as compared to control animals. The same tumors showed a significant increase in Mac-1+ leukocytes, which correlated well with the increase in chemokine and TNF-alpha gene expression. The renal cell carcinoma tumor itself may be responsible for the expression of chemokine genes in the tumor bed following cytokine therapy. Cultures of freshly explanted RENCA cells expressed significant levels of chemokine mRNAs when stimulated in vitro with IFN alpha, IFN gamma, and/or interleukin-2, demonstrating that this tumor cell has potential for expression of these genes in vivo. In contrast, TNF-alpha expression was not detected in cultured tumor cells. Thus TNF-alpha may be expressed by infiltrating monocytes following exposure to recombinant cytokine therapy.

Animals↗