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Interleukin-8 (IL-8) is a pro-angiogenic cytokine associated with aggressive prostate cancer (CaP). We detected high levels of IL-8 in sera from patients with CaP compared with healthy controls and patients with benign prostatic hypertrophy. This study examines the role of IL-8 in the pathogenesis of metastatic prostate cancer. We developed a biocompatible, cationic polylactide (CPLA) nanocarrier to complex with and efficiently deliver IL-8 small interfering RNA (siRNA) to CaP cells in vitro and in vivo. CPLA IL-8 siRNA nanocomplexes (nanoplexes) protect siRNA from rapid degradation, are non-toxic, have a prolonged lifetime in circulation, and their net positive charge facilitates penetration of cell membranes and subsequent intracellular trafficking. Administration of CPLA IL-8 siRNA nanoplexes to immunodeficient mice bearing human CaP tumours produced significant antitumour activities with no adverse effects. Systemic (intravenous) or local intra-tumour administration of IL-8 siRNA nanoplexes resulted in significant inhibition of CaP growth. Magnetic resonance imaging and ultrasonography of experimental animals demonstrated reduction of tumour perfusion in vivo following nanoplex treatment. Staining of tumour sections for CD31 confirmed significant damage to tumour neovasculature after nanoplex therapy. These studies demonstrate the efficacy of IL-8 siRNA nanotherapy for advanced, treatment-resistant human CaP.

This study is one in series determining the potential of RAGE axis (receptor for advanced glycation end products, isoforms, ligands) as a biomarker in multiple sclerosis (MS). We evaluated serum levels of RAGE ligand, the high-mobility group box (HMGB)1 in MS patients, and assessed the correlation between HMGB1 serum levels and the use of disease-modifying drugs (DMDs), and between HMGB1 serum levels and indicators of MS disease severity. HMGB1 serum levels were compared between 96 (23 males) MS patients and 34 age- and gender-matched healthy controls (HCs) using enzyme-linked immunosorbent assays. DMD-naive MS patients had significantly higher HMGB1 serum levels compared with DMD-treated (P = 0.04) and compared with HCs (P = 0.01). HMGB1 serum levels were not significantly different between total MS patients (DMD-naive plus DMD-treated) and HCs (P = 0.09). DMD-naive MS patients in clinical relapse tended to have lower HMGB1 serum levels than clinically stable RRMS patients (P = 0.07). HMGB1 serum levels showed 0.65 area under the curve (95 % CI 0.55–0.95) sensitivity/specificity for MS clinical relapse. The role of HMGB1 in MS disease pathology and DMD modulation of this protein warrant further investigations.

Matrix metallaprotinase-9 (MMP-9) is zinc-containing proteinase whose expression and trafficking are frequently altered in cancer. MMP-9 in the plasma membrane and the secreted forms are thought to contribute to the invasive and metastatic properties of malignant tumors. We have manipulated the expression of MMP-9 in prostate tumor cell line LNCaP and measured their capacity to invade through a basement membrane matrix. Stable expression of human MMP-9 in a poorly metastatic LNCaP prostate cancer cell line produced a 2-3-fold increase in MMP-9 activity and a comparable increase in invasiveness. Transient transfection of LNCaP stable clone expressing MMP-9 with MMP-9 antisense oligonucleotide (ASODN) produced 55-90% less MMP-9 than control cells and were proportionately less invasive. In contrast, manipulating MMP-9 levels had no effect on cell migration across an uncoated membrane. A standard MMP-9 inhibitor at a concentration ranging from 1-10 nM, caused a nearly quantitative inhibition of extracellular MMP-9 activity and had significant effect on basement membrane invasion. Collectively, these results confirm the role of MMP-9 in tissue remodeling associated with prostate tumor invasion.

BACKGROUND Many viral and neoplastic diseases are resistant to interferon-α/β (IFN-α/β) therapy or develop resistance during the course of IFN treatment. In patients with viral diseases, the authors identified four IFN inhibitors, of which the most important, most likely is a free IFN receptor of type 1 appearing in the circulation that captures and neutralizes IFN-α/β. METHODS Ninety-one cancer patients and 25 healthy individuals were studied. Free circulating IFN receptor-α/β type 1 was studied. The patients were ages 35–75 years. The diagnoses were 24 cases of colon carcinoma, 7 cases of prostate carcinoma, 16 cases of breast carcinoma, 8 cases of ovarian carcinoma, 9 cases of uterine carcinoma, 5 cases of lung carcinoma, 3 cases of astrocytoma, 4 cases of transitional cell carcinoma of the bladder, 1 case of osteosarcoma, 3 cases of multiple myeloma, 4 cases of Hodgkin disease, 2 cases of non-Hodgkin lymphoma, 3 cases of myelodysplastic syndrome, and 2 disseminated tumors of unknown origin. RESULTS All patients were found to have increased free IFN receptor-α/β type 1 in the circulation, with the highest levels reported in patients with adenocarcinoma. CONCLUSIONS High IFN inhibitory activity in patients with cancer may be a significant factor in their increased susceptibility to progressive disease, infectious complications, and resistance to IFN therapy. Ongoing studies are being performed with the objective of overcoming this inhibitory activity. Cancer 2003;98:2730–3. © 2003 American Cancer Society.

Earlier studies have supported a significant role for cocaine in the susceptibility to and the progression of human immunodeficiency virus type 1 (HIV-1) infection. Recently, several unique HIV-1 entry coreceptors (e.g., CCR5 and CCR3) and a trio of HIV-1-specific suppressor chemokines, namely, RANTES (regulated-upon-activation T expressed and secreted), macrophage inflammatory protein 1α (MIP-1α) and MIP-1β, were identified. Although cocaine has been linked to the immunopathogenesis of HIV-1 infection, the corresponding cellular and molecular mechanism(s) have not been well defined. We hypothesize that cocaine mediates these pathologic effects through the downregulation of HIV-1-suppressing chemokines and/or upregulating HIV-1 entry coreceptors in HIV-1-infected subjects, resulting in disease progression to AIDS. Our results show that cocaine selectively downregulates endogenous MIP-1β secretion by normal peripheral blood mononuclear cells (PBMC), while cocaine did not affect the MIP-1β production by PBMC from AIDS patients. Cocaine also selectively suppresses lipopolysaccharide-induced MIP-1β production by PBMC from HIV-infected patients. Further, cocaine significantly downregulates endogenous MIP-1β gene expression, while it upregulates HIV-1 entry coreceptor CCR5 by normal PBMC. These studies suggests a role for cocaine as a cofactor in the pathogenesis of HIV infection and support the premise that cocaine increases susceptibility to and progression of HIV-1 infection by inhibiting the synthesis of HIV-1 protective chemokines and/or upregulating the HIV-1 entry coreceptor, CCR5.

It is now well established that parenteral drug abuse is a significant risk factor for contracting human immunodeficiency virus type 1 (HIV-1) infection and subsequently developing AIDS. Earlier studies have shown that morphine can modulate various immune responses and therefore support the premise that morphine is a cofactor in susceptibility to and progression of HIV infection. Dysregulation of interferon (IFN) production, nonspecific apoptosis of T cells, and the immune response to soluble HIV gene products have been associated with potential mechanisms of pathogenesis in HIV disease. The present study was undertaken to examine the immunomodulatory role of morphine on HIV protein-induced lymphocyte proliferative responses, Sendai and Newcastle disease virus-induced alpha IFN (IFN-alpha) and IFN-beta production by lymphocytes and fibroblast cells, respectively, and induction of apoptosis of normal lymphocytes in vitro. Our results demonstrate that HIV protein-induced human lymphocyte proliferative responses were significantly inhibited by morphine in a dose-dependent manner. Furthermore, morphine significantly inhibited both IFN-alpha and IFN-beta production by normal lymphocytes and fibroblasts but induced apoptosis of normal lymphocytes. Inhibition of IFN-alpha production by morphine could be reversed by the opiate receptor antagonist naloxone. This suggests that the immunomodulatory effects of morphine are mediated through the opioid receptor. These studies support a role of morphine as a cofactor in the pathogenesis of HIV infection and describe some of the possible pathologic mechanisms which underlie the immunoregulatory effects of morphine.

While considerable progress in examining the course of human immunodeficiency virus (HIV) infection in adults has been made, a better understanding of the natural history of perinatal HIV infection remains to be obtained. Dysregulation of the production and functions of various cytokines, especially the interferons (IFNs), during HIV infections has been reported. Using an in vitro model system, we examined the effects of the HIV type 1 envelope protein, gp120 (10, 50, and 100 ng/ml), on gamma IFN (IFN-gamma) and IFN-alpha production by lymphocytes from neonates and adults and also examined the potential regulatory effects of gp120 on phorbol 12-myristate acetate (PMA)- and Sendai virus-induced IFN-gamma and IFN-alpha production by lymphocytes. PMA at a concentration of 50 ng/ml plus 50 ng of calcium ionophore A23187 per ml was used to induce IFN-gamma, while 150 hemagglutinating units of Sendai virus was used to induce IFN-alpha production. The antiviral activity of both IFN-alpha and IFN-gamma in leukocyte culture supernatants was assayed on BG-9 cells by a dye uptake technique using vesicular stomatitis virus as a challenge virus. Placental cord blood leukocyte (CBL) samples from healthy, term infants and adult peripheral blood leukocytes (APBL) produced no IFN in response to gp120. However, CBL produced significantly decreased levels of IFN-gamma compared with APBL in response to PMA plus ionophore. gp120 significantly suppressed both Sendai virus-induced IFN-alpha and PMA-induced IFN-gamma production by both CBL and APBL in a dose-dependent manner. However, gp120-induced suppression of IFN-alpha and IFN-gamma was significantly greater with CBL than with APBL. Treatment of CBL and APBL with gp120 did not induce any phenotypic alteration of the CD45 RO+ subset. Increased suppression of IFN-alpha and IFN-gamma production by gp120 in neonates may partially explain their apparent increased susceptibility to the clinical progression of HIV infections compared with that of adults.

The study is aimed to determine the role of luteolin (3',4',5,7-tetrahydroxyflavone), alone and in combination with human interferon-beta (IFN-beta), in modulating the immune response(s) of peripheral blood mononuclear cells (PBMCs) isolated from multiple sclerosis (MS) patients. PBMC proliferation in the presence or absence of these drugs was determined and the production of pro-inflammatory cytokines (IL-1beta, TNF-alpha), and the ratio of cell migration mediator MMP-9, and its inhibitor, TIMP-1 was assessed in the culture supernatants. Luteolin reduced, in a dose-dependent manner, the proliferation of PBMCs, and modulated the levels of IL-1beta and TNF-alpha released by PBMCs in the culture supernatants. Luteolin reduced the MMP-9/TIMP-1 ratio via lowering MMP-9 production. In the majority of cases, luteolin, when combined with IFN-beta, had additive effects in modulating cell proliferation, IL-1beta, TNF-alpha, MMP-9 and TIMP-1.

We have described a nonantibody type inhibitor of interferons (IFN) in the blood of patients with AIDS, advanced neoplastic disorders, and lupus erythematosus in earlier reports (1,2). In the present study we show that the semipurified inhibitor blocks the antiproliferative signal of IFN-alpha in Daudi cells and the membrane potential shifting ability of IFN-alpha is modulated by the interferon inhibitor preparation (IFI).

BACKGROUND Prostate-specific antigen (PSA) is a well-known biomarker for diagnosis and management of prostate cancer. PSA has been shown to have anti-angiogenic activity. We used the emerging proteomic research technology to identify proteins in prostate cancer cells whose expression is regulated by enzymatically active PSA. METHODS Differentially expressed proteins in PC-3M cells treated with PSA were analyzed by 2D-DIGE analysis and identified by HPLC–MS/MS and SEQUEST data mining. Biological network analysis was carried out using MetaCore integrated software designed for functional analysis of experimental data. Gene expression data for several regulated proteins were confirmed by real-time, quantitative PCR. RESULTS A total of 41 proteins were significantly (P

The study is aimed to determine the role of quercetin (3,3'4',5,7-pentahydroxy flavone), alone and in combination with human interferon-beta (IFN-beta), in modulating the immune response(s) of peripheral blood mononuclear cells (PBMC) isolated from multiple sclerosis (MS) patients and from normal healthy subjects. PBMC proliferation in the presence or absence of these drugs was determined and the production of proinflammatory cytokines (IL-1beta, TNF-alpha), and the ratio of cell migration mediator MMP-9, and its inhibitor, TIMP-1 were assessed in the culture supernatants. Quercetin reduced, in a dose-dependent manner, the proliferation of PBMC and modulated the level of IL-1beta and TNF-alpha released by PBMC in the culture supernatants. Quercetin reduced the MMP-9/TIMP-1 ratio via lowering MMP-9 production. Quercetin, when combined with IFN-beta, had additive effects in modulating TNF-alpha and MMP-9. These immunomodulatory responses to quercetin were similar between MS patients and healthy control (HC) subjects.

Synthesis of interferon (IFN) in response to Sendai virus and the development of the resulting antiviral state were studied in human (BG-9) and murine (L-929) fibroblast cell cultures in the presence of the calmodulin antagonists, trifluoperazine (TFP) and N-(6-aminohexyl)-5-chloro-1-naphthalenesulfonamide (W-7). Compared to control cultures, 16-fold and 8-fold more IFN was formed in human and murine cells, respectively, when 10 microM TFP was present in the medium for 24 h prior to IFN induction with Sendai virus. W-7 did not affect IFN production in human cells, but enhanced it in L-929 cells by 4- to 8-fold. TFP inhibited the antiviral state induced by homologous IFN in the two cell systems, and at 20 microM, there was a 3,000-fold increase in vesicular stomatitis virus (VSV) yield. It also reduced the maintenance of the antiviral state in human cells. In contrast, W-7 had no effect on the development of the antiviral state in either of the two cell systems. Thus, calcium-calmodulin dependent cellular processes are involved in both induction of IFN and its action. The several patterns response to TFP and W-7 may reflect different ligand-binding sites on calmodulin.

Although the CD4 molecule is the primary receptor for HIV-1, several studies have shown that in addition to CD4, other co-receptors such as CCR3, CCR5 may be required for efficient viral entry. Recent studies show that HIV suppressing such as, RANTES, and can bind to HIV-1 entry co-receptors, and, therefore, are important host factors that can influence susceptibility to M-tropic HIV-1 (Broder and Cocchi). Cocaine is one of the most widely abused drugs in the U.S. The last decade has witnessed a great, entangled epidemic of cocaine abuse and HIV-1 infections. Several studies have described the association of cocaine use with susceptibility to and progression of HIV-1 infections (Donahoe, Webber and Bagasra). We hypothesize that cocaine can mediate these pathologic effects through modulation of HIV suppressing chemokine and their receptors. The present study examines the effect of cocaine on synthesis by lymphocytes from normal and HIV infected subjects and and CCR 5 gene expression by normal PBMC.

Interferon (IFN) resistance is an important factor in the pathophysiology of neoplastic disorders, certain viral infections (e.g., AIDS), and autoimmune diseases (e.g., lupus erythematosus and Wegner's granulomatosis). In addition, in some of these disorders, there is also decreased ability to produce IFNs. The capacity of viruses and neoplastic processes to interfere with the IFN system are thought to represent a “virus-against-host” or “cancer-against-host” defense mechanism. Four resistance factors have been identified: 1) release of free IFN-α/β type 1 receptors into the circulation that, at appropriate concentrations, capture and inactivate IFNs; 2) a new IFN inhibitory protein has been isolated and its chemical structure is under study; 3) prostaglandin E2, which is produced by certain tumor cells, inhibits IFN production; and 4) high levels of cAMP phosphodiesterases present, for example in certain tumor cells, reduces cAMP, an important second messenger in IFN synthesis. Studies are under way to reverse these inhibitory effects and to increase endogenous interferon production.

An inhibitor of interferon antiviral activity, which is absent in healthy HIV-seronegative persons, was detected in the sera of all 29 HIV-seropositive study participants. The relationship of the level of interferon inhibitor to CD4 count and HIV-RNA copy number was statistically significant in distinct models. Levels of interferon inhibitor declined by an average of 41-60% in patients who underwent a change in anti-retroviral therapy. Interferon inhibitor levels appear to decline as CD4 cell count rises and HIV-RNA levels fall. This suggests that interferon inhibitor may have a significant role in the host immune response to HIV infection.

A three-group design of alcoholics, heavy smokers and controls was used to investigate the status of the interferon system, including natural killer cell activity. Group differences were indicated via discriminant function analysis which correctly classified 86% of subjects. Test-retest relations were investigated for 14 subjects following a 30-day alcoholic inpatient program. Whereas significant immune suppression was indicated at the time of detoxification, recovery was evident at the 30-day follow-up. Results are discussed in terms of the significance of alcohol abuse on immune system functioning with consequences for susceptibility to viruses, bacteria and medical illnesses.

Spleen cells from C57BL/6 mice maintained on alcohol containing liquid diet for two weeks were evaluated for different immune functions. On an average, 22% fewer spleen cells were recovered from alcohol-fed mice when compared to cells from control animals. In alcohol-fed mice, the relative frequency of B cells increased, whereas total T cells including CD4 + cells decreased significantly. Alcoholic mice, when challenged with poly(rI) poly(rC), produced significantly less interferon than control mice. In vitro production of interferon alpha and gamma by the spleen cells of alcoholic mice was reduced by 67–90%. No significant differences were seen in the level of natural killer cell activity in spleen cells of control and alcoholic mice. These results suggest that chronic alcohol intake can result in not only changes in the number of immune cells, but more importantly affect their biological functions such as their ability to produce interferons.

Human leukocyte-derived interferon (HuIFN-alpha) can be displaced from controlled-pore glass (CPG) with alkylamines at 0.1-0.3 M concentration. The eluting power of an alkylamine correlates positively with the extent of its alkylation: CH3NH3 + less than (CH3)2NH2 + less than (CH3)3NH+ less than (CH3)4N+. Interferon can also be recovered using an electrolyte and ethylene glycol as cosolvents. Apparently, both hydrophobic and electrostatic forces are involved in the adsorption of HuIFN-alpha to CPG.

Antiviral and antiproliferative activities of three naturally occurring components of leukocyte-derived human interferon (HuIFN-alpha) separated by concanavalin A-agarose affinity chromatography were studied in a variety of neoplastic cell lines. Significant differences were seen with these different components. The results strongly suggest that careful consideration must be given while selecting any one component of HuIFN-alpha for any of the antiviral or antiproliferative studies. There is no clear evidence that glycosylation of HuIFN-alpha has any significant influence on its in vitro antiviral or antiproliferative activities, although apparently glycosylated and non-glycosylated components gave different antiviral and antiproliferative responses in different tumor cells.

The extracellular, acid-soluble cell products (EASCP) from Newcastle disease virus-infected L 929 cells contain both interferon, defined as antiviral activity, and refractoriness inducing principle, defined as an activity that inhibits interferon production. L cells pretreated with EASCP and then infected with Newcastle disease virus give rise to EASCP with decreased amounts of interferon but an increased ratio of refractoriness inducing principle activity to interferon activity in a dose related manner. The antiviral activity of an EASCP preparation is not dependent upon its refractoriness inducing principle level, but is entirely dependent on its interferon content. Our results provide additional evidence that interferon and refractoriness inducing principle are different biological entities and not polymorphic functions of the interferon molecule.

Interferon inhibitory activity was found in the plasma of 11 of 14 patients with the acquired immune deficiency syndrome (AIDS). This was not seen in 75 normal persons, including six whose specimens were randomly and blindly interspersed among the patient samples. Plasma from a single patient with the AIDS prodrome (AIDS-related complex), who later demonstrated AIDS, did not contain interferon inhibitors but did contain high levels of interferon. Three patients with AIDS-unrelated Kaposi's sarcoma had neither significant levels of interferon nor interferon inhibitory activity. The existence of interferon inhibitory activity in the plasma has to be taken into account when interferon preparations are administered therapeutically.

Purpose Previous studies had reported that normal individuals do not have measurable levels of interferons in their circulation, whereas high levels have been found in patients in the early stages of AIDS (acquired immunodeficiency syndrome) and in those with AIDS-related complex (ARC). This study was undertaken to compare levels of interferon and interferon inhibitors in plasma samples from patients with AIDS, ARC, Kaposi's sarcoma, or varicella-zoster virus infection, and from control subjects. Patients and methods A total of 206 persons were tested for the presence of interferon and interferon inhibitors in their plasma: 76 with ARC or AIDS, with or without Kaposi's sarcoma or lymphoma; 32 with varicella-zoster infection; 12 with AIDS-unrelated Kaposi's sarcoma; and 86 normal control subjects at high or low risk of AIDS with or without positive antibody levels to human immunodeficiency virus-1. Total interferon activity was measured by bioassay and the subtypes were not separated. Results Of 86 normal control subjects, 85 had no significant levels of interferon or interferon inhibitor. One disease-free homosexual exhibited measurable interferon levels. Patients acutely infected with varicella-zoster virus showed no measurable interferon or inhibitor levels except if they were in a high-risk group for AIDS. Seventy-six patients with ARC or AIDS exhibited measurable circulating interferon levels. Only patients with AIDS had interferon inhibitors in their circulation. Of 12 patients with Kaposi's sarcoma unrelated to AIDS, none had measurable interferon inhibitor levels, but some exhibited measurable interferon levels. Conclusion It is suggested that levels of interferon inhibitor should be considered when interferon is used therapeutically in viral or neoplastic diseases.

The influence of splenectomy upon the growth of B16-F10 malignant melanoma and changes in interferon-synthesizing ability in mice were studied. Surgical stress alone temporarily diminished the ability of mice to respond to interferon induction by poly rIrC. Two weeks following the surgery, mock-splenectomized mice fully regained their interferon synthesis ability. However, this was not true in the case of splenectomized mice. They remained refractory to interferon induction. The removal of the spleen had no obvious effect on the rate of pulmonary metastasis in mice injected with B16-F10 malignant melanoma in relation to the mock-splenectomized or control mice. Mice that were splenectomized and inoculated with B16-F10 melanoma also remained refractory to interferon induction.

The phenotype of the human effector leukocyte subset involved in production of alpha interferon was examined using positive and negative selection techniques including murine monoclonal antibodies. The data suggest that the effector cell responsible for the elaboration of human alpha interferon is surface immunoglobulin positive, lacks either the E-rosette receptor or any monocyte determinants and is also negative for expression of the surface antigens identified by Leu-10 and Leu-11b monoclonal antibodies. Neither monocytes nor polymorphonuclear leukocytes were shown to play a role in regulation or production of alpha interferon. The data further imply, however, that the Leu-7+, large granular lymphocyte subpopulation may play a critical role in regulating human alpha interferon production by surface immunoglobulin positive B cell effectors.

The interferon (IFN) system of human cornea cells in culture was studied. IFN produced by these cells by infection with Newcastle disease virus (NDV) was shown, by neutralization studies with specific antisera against human alpha interferon (HuIFN-alpha) and human beta interferon (HuIFN-beta), to contain 90-95% antiviral activity characteristic of the HuIFN-beta and 5-10% that of HuIFN-alpha. The chromatographic behavior of human cornea IFN on Con A-Sepharose and zinc chelate agarose columns was identical to that of HuIFN-beta produced by human foreskin cells. The cornea cells developed marked resistance when exposed to either HuIFN-beta or human gamma interferon (HuIFN-gamma) against vesicular stomatitis virus (VSV), but to a much lesser degree against HSV-1. Both the laboratory-adapted strain and a clinical isolate of HSV-1 were found to be resistant to HuIFN-beta and HuIFN-gamma as compared with VSV. The clinical isolate of HSV-1 was, however, more sensitive to HuIFN-gamma than the laboratory-adapted strain. Furthermore, a combination of HuIFN-beta and HuIFN-gamma did not significantly increase the level of antiviral state induced in cornea cells against HSV-1. These results suggest that in-vitro culture of human cornea cells can be a valuable system to evaluate the potential of chemotherapeutic agents against common ophthalmic viral infections.

It is becoming increasingly evident that changes in various parameters of the interferon system and in the levels of prostaglandins and cyclic nucleotides have a definite role during the health and during the onset, progression and the final outcome of any disease process. In spite of ever increasing excitement over the possible clinical application of interferons, very little is known about the changes and sources of variations in the interferon production capabilities of different individuals. Heterogeneity of human interferons is now well document from the earlier work (1) as well as from more recent work based upon DNA recombinant technology (2–4). However, the clinical significance of such a heterogeneity is not known. Cloned interferons used at present in the treatment of any type of infections are a product of a single gene. It is quite possible that expression of different interferon genes varies considerably in different types of infections and malignancies. If that is the case, it may be necessary to use a custom-tailored interferon preparation for each type of infection. Such an approach at best appears to be several years away. In view of lack of such a knowledge, it seems appropriate that serious attempts should be made towards better understanding of the host’s own interferon system during infection and ways and means of its manipulation for maximal benefit. In this text, some attempts have been made in this direction.