Malignant melanoma is a highly metastatic tumor to the skin, liver, lung and especially the brain... more Malignant melanoma is a highly metastatic tumor to the skin, liver, lung and especially the brain. Patients with brain metastases have a poor prognosis despite aggressive chemo-and radiotherapy. Many of these patients have disseminated melanoma but eventually succumb to their cerebral metastatic disease.
Para-boronophenylalanine (BPA) has been used as a boron delivery agent for boron neutron capture ... more Para-boronophenylalanine (BPA) has been used as a boron delivery agent for boron neutron capture therapy (BNCT) of melanoma1. As an analogue of phenylalanine, a melanin precursor, it has been postulated that melanoma cells selectively take up BPA. The effectiveness of BNCT is dependent, in part, upon the concentration gradient of boron in the tumor in comparison with the surrounding normal tissues and blood. Consequently, it is important to determine the pharmacokinetics and tissue distribution of BPA and other boron compounds in order to evaluate the potential effectiveness of BNCT agents.
Objectives: Dopamine (DA) administration in sepsis is used to modulate the hypotensive condition ... more Objectives: Dopamine (DA) administration in sepsis is used to modulate the hypotensive condition and to normalize the blood vessels perfusion. However, whether this administration of DA has an effect on the release of cytokines in vivo deserves investigation. Methods and results: Pre-exposure of DA (1 µg/ml) to whole blood enhanced IL-10 (30%) production level following LPS stimulation. This IL-10 enhancement became statistically significant (p<0.001) upon the addition of D2-DA receptor (DAR) antagonists, Clozapine or Haloperidol. Furthermore, systemic administration of DA (0.5-50 mg/kg) in mice suppressed significantly LPS-induced TNF-α levels in blood, liver, spleen, brain, and lungs; IL-10 levels in blood, brain and liver; and IFN-γ levels in blood, liver, brain, and lungs. On the other hand, DA enhanced significantly LPS-induced IL-10 production in the lungs and spleen, and IFN-γ levels in the spleen. Administration of Clozapine (54 mg/kg) or Haloperidol (62 mg/kg) with LPS (1 µg) and DA (5 mg/kg) reversed DA suppressive effects on LPS-induced cytokines in blood, IFN-γ in brain and lungs, and enhanced significantly LPS-induced IL-10 production in blood, spleen, liver, and lungs. Conclusions: These results indicate that DA modulatory effect on LPS-induced blood cytokines-producing cells is mediated mainly by D2-DAR (D2/ D3/D4) through enhancing immune cells migration and extravasation into tissues. Furthermore, DA selectivity on cytokines modulation is tissue specific, mediated by the type of DAR expressed and on the immune cells lodged in each tissue.
A rat brain tumor model has been developed utilizing nude rats and the human melanoma cell line M... more A rat brain tumor model has been developed utilizing nude rats and the human melanoma cell line MRA 27. For pharmacokinetic and tissue distribution studies, 2 10(5) MRA 27 cells were implanted intracerebrally (i.c.), and 30 days later, 120 mg of 10B-enriched L-boronophenylalanine were injected i.p. into nude rats. 10B concentrations in the tumor, blood, and normal brain were 23.7, 9.4, and 8.4 micrograms/g, respectively, 6 h following administration. For therapy experiments, tumor bearing rats were irradiated at the Brookhaven Medical Research Reactor 30 days following implantation. The median survival time was 44 days for untreated rats, 76 days for those receiving a physical dose of 2.7 Gy, and 93 days for those receiving 3.6 Gy. Animals receiving both 10B-L-boronophenylalanine and physical doses of 1.8, 2.7, or 3.6 Gy (total tumor physical doses of 5.0, 7.5, or 10.1 Gy) had median survival times of 170, 182, and 262 days, respectively. Forty % of rats that received the highest tumor dose (10.1 Gy) survived > 300 days. In a replicate experiment 21% of animals that had received L-boronophenylalanine and irradiation (total tumor physical dose of 10.1 Gy) were alive 220 days after therapy. In a parallel study, animals that were irradiated with gamma photons from a 137Cs source with 12 Gy or 2.0 Gy 9 delivered to the head had median survival times of 86 and 79 days, respectively, compared to 47 days for untreated animals. Our results indicate that boron neutron capture therapy is effective against i.c. melanoma in a rodent model and suggest that large animal studies are warranted to further assess its efficacy.
Objectives: Previously, a large number of studies reported that psychological stress and psychiat... more Objectives: Previously, a large number of studies reported that psychological stress and psychiatric illness reduces immune responsiveness. However, it turned out that stress reduces immune responsiveness is an oversimplified statement because the interactions between central nervous system, endocrine system and the immune system are undoubtedly complex. Therefore, this study aims in reviewing mental stress models (e.g. brief and written examination stress as subacute and acute type of stressor) that have been utilized to understand the effect of stress on the neuroendocrine and immune systems. Methods: The published findings from human mental stress models on catecholamines, cortisol, prolactin levels and on T helper (Th) 1 and 2-induced cytokines are presented and discussed with respect to the in vitro and in vivo effects of glucocorticoids, catecholamines, and prolactin on the induction of cytokines. Results: This review shows evidence that short-time (minutes) or preparation to a written examination, in those students who are stressed, induces the production of proinflammatory cytokines which may be related to Th1 response. However, longer mental stress (days) causes dysregulation in the immune function by shifting the cytokine response to Th2 response. Conclusions: The outcome from neuroendocrine and immune function prior to, following and after mental stress depends on multiple variables most importantly on the amount of stress, exposure time, coping behavior and adjustment of the individual. A few minutes of stress may improve immune performance but longer times of mental stress have detrimental effects that may lead to loss of immune integrity. Furthermore, studies on stress and common heath problems are necessary to increase our knowledge and understanding of the mechanisms responsible for producing neuroendocrine-induced immune changes in health and common diseases.
Glial neoplasms of the human central nervous system have defied treatment, in part because of the... more Glial neoplasms of the human central nervous system have defied treatment, in part because of the limited selectivity of available cytotoxic agents. The thymidine analog 5-iodo-2'-deoxyuridine radiolabeled with the Auger electron emitter 125I (125IUdR) is highly toxic to dividing cells when it is deoxyribonucleic acid incorporated, but it is relatively innocuous when located outside the nucleus. Previous studies have shown that 125IUdR has significant antineoplastic potential against mammalian cells in vitro and direct administration of 125IUdR is effective therapy for ovarian ascites tumors in mice and neoplastic meningitis in rats. Studies using external gamma imaging and autoradiography have also shown that direct intratumoral administration of 123IUdR/125IUdR into intracerebral 9L gliosarcomas in rats results in selective uptake of the radionuclide into tumor cells. Based on these encouraging results, we have evaluated the therapeutic potential of 125IUdR in rats bearing intracerebral 9L gliosarcomas. Methods: Iodine-125-IUdR was infused intracerebrally over a 2-day period into rats bearing 1-day-old 9L tumors and over a 6-day period into animals with 9-day-old 9L tumors; equimolar concentrations of 127IUdR were infused into control animals. Tumor growth was monitored by contrast-enhanced 1H MRI and animal survival was followed over time. Results: Intracerebral tumors (3-7 mm) were readily detected by MRI. Tumor-bearing rats treated with 127IUdR succumbed within 17-24 days, whereas tumor-bearing animals treated with 125IUdR survived significantly longer, and 10%-20% of the animals were cured of tumors. Conclusion: These data substantiate the antineoplastic potential of 5-[125I]iodo-2'-deoxyuridine and indicate that it may be a useful agent for the therapy of solid tumors that are accessible to direct radiopharmaceutical administration.
Objectives: Determination of protein cytokines in local tissues would help to evaluate their loca... more Objectives: Determination of protein cytokines in local tissues would help to evaluate their local role in health, sickness behavior and immune-mediated diseases. Therefore, developing a simple quantitative method of protein cytokines in tissues/organs is highly important. Methods: Mouse tissues were collected following intraperitoneal administration of endotoxin-free PBS or lipopolysaccharide. A mild detergent, 0.1% Igepal, was added in a buffer to enhance cytokines extraction. The tissues were then disrupted, homogenized, centrifuged and the supernatants were collected and assayed using solid-phase immunoassays. Results: The presence of 0.1% Igepal extracted significantly more TNF-alpha from liver (322%: p<0.01), brain (358%: p<0.05), lungs (1600%: p<0.01), and more IL-10 from liver (220%: p<0.001), brain (4650%: p<0.001) than PBS alone. On the other hand, using 0.1% Igepal did not increase IFN-gamma extraction from liver, spleen, brain, lungs, skin and kidneys more than PBS alone. Furthermore, i.p. administration of LPS induced a differential milieu of cytokines. LPS increased significantly the production of TNF-alpha, IFN-gamma, and IL-10 from liver (521%, 123%, 72%: p<0.01, 0.04, 0.04), brain (470%, 122%, 280%: p< 0.01, 0.03, 0.01), peritoneal lavage (p<0.001) and blood (p<0.001). However, the pattern of increase was different for the above cytokines in spleen, skin, lungs and kidneys. Conclusions: The extraction of protein cytokines from tissues was superior with addition of mild detergent. Furthermore, our results showed a differential cytokines response to LPS with respect to tissue and cytokine type. This method should provide an important tool for studying local protein cytokines in behavioral pattern, sickness behavior, and immune-mediated diseases as well as to determine local therapeutic efficacy of immunomodulatory drugs.
Objectives: The purpose of this study was to determine the effects of estradiol and progesterone ... more Objectives: The purpose of this study was to determine the effects of estradiol and progesterone on interferon-gamma (IFN-gamma), interleukin (IL)-12, IL-10 and tumor necrosis factor-alpha (TNF-alpha) productions in polyclonal activators (phytohemagglutinin+lipopolysaccharide)-stimulated whole blood cultures. Methods: Nineteen healthy males and females volunteered in the study. Blood samples were drawn, diluted, and cultured for 24h with different concentrations of estradiol, progesterone or hydrocortisone and then PHA+LPS was added for another 24 h. The supernatant, then, was harvested and assayed for IL-12 p70, IFN-gamma, IL-10 and TNF-alpha. Results: At preovulatory concentrations, estradiol enhanced significantly IFN-gamma, IL-12 and IL-10, but not TNF-alpha, production levels and reversed the suppressive effect of hydrocortisone in PHA+LPS stimulated whole blood. While IL-10 levels kept increasing at pregnancy estradiol concentrations, IFN-gamma, IL-12 levels and IFN-gamma/IL-10 ratio decreased significantly. No effect of progesterone on IL-12 p70, IFN-gamma, IL-10 and TNF production levels was observed. Conclusions: The present study shows that those pregnancy estradiol concentrations (and higher) enhance the production of IL-10 and reduce IL-12, IFN-gamma levels and IFN-gamma/IL-10 ratio in stimulated whole blood cells. Because of the known IL-10 inhibitory actions on T helper (Th) 1 cells and monocytes/macrophages, these high IL-10 levels keep Th2 cytokines favored during pregnancy and may be useful in shifting Th1-mediated autoimmune diseases towards non-pathogenic Th2 pathway.
Malignant melanoma is a highly metastatic tumor to the skin, liver, lung and especially the brain... more Malignant melanoma is a highly metastatic tumor to the skin, liver, lung and especially the brain. Patients with brain metastases have a poor prognosis despite aggressive chemo-and radiotherapy. Many of these patients have disseminated melanoma but eventually succumb to their cerebral metastatic disease.
Para-boronophenylalanine (BPA) has been used as a boron delivery agent for boron neutron capture ... more Para-boronophenylalanine (BPA) has been used as a boron delivery agent for boron neutron capture therapy (BNCT) of melanoma1. As an analogue of phenylalanine, a melanin precursor, it has been postulated that melanoma cells selectively take up BPA. The effectiveness of BNCT is dependent, in part, upon the concentration gradient of boron in the tumor in comparison with the surrounding normal tissues and blood. Consequently, it is important to determine the pharmacokinetics and tissue distribution of BPA and other boron compounds in order to evaluate the potential effectiveness of BNCT agents.
Objectives: Dopamine (DA) administration in sepsis is used to modulate the hypotensive condition ... more Objectives: Dopamine (DA) administration in sepsis is used to modulate the hypotensive condition and to normalize the blood vessels perfusion. However, whether this administration of DA has an effect on the release of cytokines in vivo deserves investigation. Methods and results: Pre-exposure of DA (1 µg/ml) to whole blood enhanced IL-10 (30%) production level following LPS stimulation. This IL-10 enhancement became statistically significant (p<0.001) upon the addition of D2-DA receptor (DAR) antagonists, Clozapine or Haloperidol. Furthermore, systemic administration of DA (0.5-50 mg/kg) in mice suppressed significantly LPS-induced TNF-α levels in blood, liver, spleen, brain, and lungs; IL-10 levels in blood, brain and liver; and IFN-γ levels in blood, liver, brain, and lungs. On the other hand, DA enhanced significantly LPS-induced IL-10 production in the lungs and spleen, and IFN-γ levels in the spleen. Administration of Clozapine (54 mg/kg) or Haloperidol (62 mg/kg) with LPS (1 µg) and DA (5 mg/kg) reversed DA suppressive effects on LPS-induced cytokines in blood, IFN-γ in brain and lungs, and enhanced significantly LPS-induced IL-10 production in blood, spleen, liver, and lungs. Conclusions: These results indicate that DA modulatory effect on LPS-induced blood cytokines-producing cells is mediated mainly by D2-DAR (D2/ D3/D4) through enhancing immune cells migration and extravasation into tissues. Furthermore, DA selectivity on cytokines modulation is tissue specific, mediated by the type of DAR expressed and on the immune cells lodged in each tissue.
A rat brain tumor model has been developed utilizing nude rats and the human melanoma cell line M... more A rat brain tumor model has been developed utilizing nude rats and the human melanoma cell line MRA 27. For pharmacokinetic and tissue distribution studies, 2 10(5) MRA 27 cells were implanted intracerebrally (i.c.), and 30 days later, 120 mg of 10B-enriched L-boronophenylalanine were injected i.p. into nude rats. 10B concentrations in the tumor, blood, and normal brain were 23.7, 9.4, and 8.4 micrograms/g, respectively, 6 h following administration. For therapy experiments, tumor bearing rats were irradiated at the Brookhaven Medical Research Reactor 30 days following implantation. The median survival time was 44 days for untreated rats, 76 days for those receiving a physical dose of 2.7 Gy, and 93 days for those receiving 3.6 Gy. Animals receiving both 10B-L-boronophenylalanine and physical doses of 1.8, 2.7, or 3.6 Gy (total tumor physical doses of 5.0, 7.5, or 10.1 Gy) had median survival times of 170, 182, and 262 days, respectively. Forty % of rats that received the highest tumor dose (10.1 Gy) survived > 300 days. In a replicate experiment 21% of animals that had received L-boronophenylalanine and irradiation (total tumor physical dose of 10.1 Gy) were alive 220 days after therapy. In a parallel study, animals that were irradiated with gamma photons from a 137Cs source with 12 Gy or 2.0 Gy 9 delivered to the head had median survival times of 86 and 79 days, respectively, compared to 47 days for untreated animals. Our results indicate that boron neutron capture therapy is effective against i.c. melanoma in a rodent model and suggest that large animal studies are warranted to further assess its efficacy.
Objectives: Previously, a large number of studies reported that psychological stress and psychiat... more Objectives: Previously, a large number of studies reported that psychological stress and psychiatric illness reduces immune responsiveness. However, it turned out that stress reduces immune responsiveness is an oversimplified statement because the interactions between central nervous system, endocrine system and the immune system are undoubtedly complex. Therefore, this study aims in reviewing mental stress models (e.g. brief and written examination stress as subacute and acute type of stressor) that have been utilized to understand the effect of stress on the neuroendocrine and immune systems. Methods: The published findings from human mental stress models on catecholamines, cortisol, prolactin levels and on T helper (Th) 1 and 2-induced cytokines are presented and discussed with respect to the in vitro and in vivo effects of glucocorticoids, catecholamines, and prolactin on the induction of cytokines. Results: This review shows evidence that short-time (minutes) or preparation to a written examination, in those students who are stressed, induces the production of proinflammatory cytokines which may be related to Th1 response. However, longer mental stress (days) causes dysregulation in the immune function by shifting the cytokine response to Th2 response. Conclusions: The outcome from neuroendocrine and immune function prior to, following and after mental stress depends on multiple variables most importantly on the amount of stress, exposure time, coping behavior and adjustment of the individual. A few minutes of stress may improve immune performance but longer times of mental stress have detrimental effects that may lead to loss of immune integrity. Furthermore, studies on stress and common heath problems are necessary to increase our knowledge and understanding of the mechanisms responsible for producing neuroendocrine-induced immune changes in health and common diseases.
Glial neoplasms of the human central nervous system have defied treatment, in part because of the... more Glial neoplasms of the human central nervous system have defied treatment, in part because of the limited selectivity of available cytotoxic agents. The thymidine analog 5-iodo-2'-deoxyuridine radiolabeled with the Auger electron emitter 125I (125IUdR) is highly toxic to dividing cells when it is deoxyribonucleic acid incorporated, but it is relatively innocuous when located outside the nucleus. Previous studies have shown that 125IUdR has significant antineoplastic potential against mammalian cells in vitro and direct administration of 125IUdR is effective therapy for ovarian ascites tumors in mice and neoplastic meningitis in rats. Studies using external gamma imaging and autoradiography have also shown that direct intratumoral administration of 123IUdR/125IUdR into intracerebral 9L gliosarcomas in rats results in selective uptake of the radionuclide into tumor cells. Based on these encouraging results, we have evaluated the therapeutic potential of 125IUdR in rats bearing intracerebral 9L gliosarcomas. Methods: Iodine-125-IUdR was infused intracerebrally over a 2-day period into rats bearing 1-day-old 9L tumors and over a 6-day period into animals with 9-day-old 9L tumors; equimolar concentrations of 127IUdR were infused into control animals. Tumor growth was monitored by contrast-enhanced 1H MRI and animal survival was followed over time. Results: Intracerebral tumors (3-7 mm) were readily detected by MRI. Tumor-bearing rats treated with 127IUdR succumbed within 17-24 days, whereas tumor-bearing animals treated with 125IUdR survived significantly longer, and 10%-20% of the animals were cured of tumors. Conclusion: These data substantiate the antineoplastic potential of 5-[125I]iodo-2'-deoxyuridine and indicate that it may be a useful agent for the therapy of solid tumors that are accessible to direct radiopharmaceutical administration.
Objectives: Determination of protein cytokines in local tissues would help to evaluate their loca... more Objectives: Determination of protein cytokines in local tissues would help to evaluate their local role in health, sickness behavior and immune-mediated diseases. Therefore, developing a simple quantitative method of protein cytokines in tissues/organs is highly important. Methods: Mouse tissues were collected following intraperitoneal administration of endotoxin-free PBS or lipopolysaccharide. A mild detergent, 0.1% Igepal, was added in a buffer to enhance cytokines extraction. The tissues were then disrupted, homogenized, centrifuged and the supernatants were collected and assayed using solid-phase immunoassays. Results: The presence of 0.1% Igepal extracted significantly more TNF-alpha from liver (322%: p<0.01), brain (358%: p<0.05), lungs (1600%: p<0.01), and more IL-10 from liver (220%: p<0.001), brain (4650%: p<0.001) than PBS alone. On the other hand, using 0.1% Igepal did not increase IFN-gamma extraction from liver, spleen, brain, lungs, skin and kidneys more than PBS alone. Furthermore, i.p. administration of LPS induced a differential milieu of cytokines. LPS increased significantly the production of TNF-alpha, IFN-gamma, and IL-10 from liver (521%, 123%, 72%: p<0.01, 0.04, 0.04), brain (470%, 122%, 280%: p< 0.01, 0.03, 0.01), peritoneal lavage (p<0.001) and blood (p<0.001). However, the pattern of increase was different for the above cytokines in spleen, skin, lungs and kidneys. Conclusions: The extraction of protein cytokines from tissues was superior with addition of mild detergent. Furthermore, our results showed a differential cytokines response to LPS with respect to tissue and cytokine type. This method should provide an important tool for studying local protein cytokines in behavioral pattern, sickness behavior, and immune-mediated diseases as well as to determine local therapeutic efficacy of immunomodulatory drugs.
Objectives: The purpose of this study was to determine the effects of estradiol and progesterone ... more Objectives: The purpose of this study was to determine the effects of estradiol and progesterone on interferon-gamma (IFN-gamma), interleukin (IL)-12, IL-10 and tumor necrosis factor-alpha (TNF-alpha) productions in polyclonal activators (phytohemagglutinin+lipopolysaccharide)-stimulated whole blood cultures. Methods: Nineteen healthy males and females volunteered in the study. Blood samples were drawn, diluted, and cultured for 24h with different concentrations of estradiol, progesterone or hydrocortisone and then PHA+LPS was added for another 24 h. The supernatant, then, was harvested and assayed for IL-12 p70, IFN-gamma, IL-10 and TNF-alpha. Results: At preovulatory concentrations, estradiol enhanced significantly IFN-gamma, IL-12 and IL-10, but not TNF-alpha, production levels and reversed the suppressive effect of hydrocortisone in PHA+LPS stimulated whole blood. While IL-10 levels kept increasing at pregnancy estradiol concentrations, IFN-gamma, IL-12 levels and IFN-gamma/IL-10 ratio decreased significantly. No effect of progesterone on IL-12 p70, IFN-gamma, IL-10 and TNF production levels was observed. Conclusions: The present study shows that those pregnancy estradiol concentrations (and higher) enhance the production of IL-10 and reduce IL-12, IFN-gamma levels and IFN-gamma/IL-10 ratio in stimulated whole blood cells. Because of the known IL-10 inhibitory actions on T helper (Th) 1 cells and monocytes/macrophages, these high IL-10 levels keep Th2 cytokines favored during pregnancy and may be useful in shifting Th1-mediated autoimmune diseases towards non-pathogenic Th2 pathway.
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