The mechanism by which a peptide based on complementarity-determining region-1 of a pathogenic anti-DNA auto-Ab ameliorates experimental systemic lupus erythematosus.

A peptide based on complementarity-determining region (CDR)-1 of a monoclonal murine anti-DNA Ab that bears the common idiotype, 16/6Id, was synthesized and characterized. The peptide, designated pCDR1, was found to be an immunodominant T-cell epitope in BALB/c mice. The CDR1-based peptide was shown to be capable of inhibiting the in vivo priming of BALB/c mice immunized with the peptide or with the whole anti-DNA 16/6Id(+) mAbs of either mouse or human origin. We show here that administration of pCDR1 (weekly, i.v., 100 microgram/mouse) in aqueous solution for 5 weeks starting at the time of disease induction with the human 16/6Id prevented the development of clinical manifestations of experimental systemic lupus erythematosus (SLE). Further, 10 weekly injections of pCDR1 to BALB/c mice with an established experimental SLE down-regulated clinical manifestations of SLE (e.g., anti-DNA auto-Abs, leukopenia, proteinuria, immune complex deposits in the kidneys) in the treated mice. Prevention of SLE induction was shown to be associated mainly with a decrease in the levels of IL-2, INFgamma, and the proinflammatory cytokine TNFalpha. On the other hand, the secretion of the immunosuppressive cytokine TGFbeta was elevated. Amelioration of the clinical manifestations of an already established experimental SLE correlated with a dramatic decrease in TNFalpha secretion, elevated levels of TGFbeta, and immunomodulation of the Th1 and Th2 type cytokines to levels close to those observed in healthy mice.

A peptide based on the CDR1 of a pathogenic anti-DNA antibody is more efficient than its analogs in inhibiting autoreactive T cells.

A peptide based on the sequence of the complementarity determining regions 1 (pCDR1) of a pathogenic murine monoclonal anti-DNA antibody (5G12) that bears the 16/6 Id, was synthesized. This peptide was shown to be immunodominant in BALB/c mice, and induced a mild lupus-like disease upon immunization. Furthermore, the pCDR1 when injected in a soluble form was capable of inhibiting the proliferation of lymph node cells primed to either the peptide or the anti-DNA, 16/6 Id antibodies of either murine (5C12) or human (16/6 Id) origin. We have designed and synthesized 39 analogs based on pCDRI with single amino acid substitutions. Out of the above, two analogs, namely, Asp14 and Ser16 inhibited the proliferative responses of a pCDR1-specific T cell line to its stimulating peptide by more than 50%. These two analogs were therefore further studied. Administration of analog Ser16 concomitant with the immunization with pCDR1 inhibited efficiently the proliferative responses of lymph node cells to pCDR1, although pCDR1 was more efficient in its inhibitory capacity. Neither of the analogs were capable of inhibiting significantly the proliferative responses to the human monoclonal anti-DNA antibody with the 16/6 Id whereas pCDR1 did so efficiently. Thus, pCDR1 is more efficient than all its tested analogs in immunomodulating SLE associated immune responses.

Prevention of systemic lupus erythematosus-like disease in (NZBxNZW)F1 mice by treating with CDR1- and CDR3-based peptides of a pathogenic autoantibody.

Two peptides based on the complementarity-determining regions (CDR) of a pathogenic murine anti-DNA antibody were employed in an attempt to prevent the spontaneous systemic lupus erythematosus (SLE)-like disease of (NZBxNZW)F1 mice. Female mice, at the age of 2 months, were injected with either the CDR1- or the CDR3-based peptides (pCDR1, pCDR3) subcutaneously or intravenously in aqueous solution for a total of 8-10 treatments. A reduction was observed in the total and pathogenic IgG2a and IgG3 anti-DNA antibody titers in the CDR-treated groups. Treatment reduced the number of mice that developed proteinuria and immune complex deposits in their kidneys. The severity of renal pathology was significantly reduced in the pCDR3 (P<0.02) and pCDR1 (P< or = 0.05) treated mice. Thus, both CDR-based peptides administered in aqueous solution were capable of preventing the SLE-like disease in (NZBxNZW)F1 mice, although the beneficial effects of pCDR3 appeared to be more pronounced than those of pCDR1 in the treated mice.

Immune response of SLE patients to peptides based on the complementarity determining regions of a pathogenic anti-DNA monoclonal antibody.

We have examined the humoral and cellular responses of SLE patients to peptides based on the complementarity-determining regions (CDR) of a monoclonal anti-DNA antibody with a major idiotype- 16/6 Id, in comparison to their responses to the whole 16/6 Id-bearing antibody. Sera of 63% of the SLE patients had antibodies that bound the 16/6 Id, 80% had antibodies to one of the CDR-based peptides, and 40% of the patients reacted with both CDRs. Sera of only a few controls reacted with either the 16/6 Id (6%) or the CDR based peptides (4%) (P < 0.01). Peripheral blood lymphocytes (PBL) of 39% of the patients proliferated in response to the 16/6 Id or to one of the CDR-based peptides (37%), while in the control group the proliferation rates were 66% to the 16/6 Id and 59% to one of the CDR-based peptides (P < 0.05). The correlation between (both) the humoral and cellular immune responses to the CDR-based peptides and to the 16/6 Id suggests the relevance of these peptides to the 16/6 Id and provides additional information on the pathogenic moiety of the latter antibody.

Characterization and role in experimental systemic lupus erythematosus of T-cell lines specific to peptides based on complementarity-determining region-1 and complementarity-determining region-3 of a pathogenic anti-DNA monoclonal antibody.

Peptides based on the complementarity-determining region 1 (CDR1) and CDR3 of an anti-DNA monoclonal antibody (mAb) carrying the 16/6 idiotype (Id) were shown to induce experimental systemic lupus erythematosus (SLE) in susceptible mouse strains. In the present study, T-cell lines specific to the pCDR1 and pCDR3 peptides were established in BALB/c and in SJL mice, respectively. The T-cell lines were characterized and analysed for their pathogenicity upon administration to syngeneic mouse strains. Both T-cell lines expressed the alphabeta T-cell receptor (TCR) and the CD4+ CD8- phenotype. Additionally, both cell lines secreted interleukin (IL)-4 and IL-10 upon stimulation with their specific peptide, thus belonged to the T helper 2 (Th2) subset. Upon immunization, the pCDR3-specific T-cell line induced experimental SLE in SJL mice. The animals produced high levels of autoimmune anti-DNA and antinuclear protein antibodies, as well as anti-16/6 Id antibodies (Abs). Furthermore, the mice developed clinical manifestations, including leukopenia, proteinuria and accumulation of immune complex deposits in their kidneys. The pCDR1-specific T-cell line failed to induce SLE when injected into BALB/c mice. It is thus suggested that pCDR3 is an immunodominant epitope in experimental SLE and that pCDR3-specific T cells initiate autoimmunity, leading to SLE, probably via epitope spreading.

Increased apoptosis in patients with major depression: A preliminary study.

Apoptosis is a programmed cell death that can be observed in normal cells. Major depression poses a combination of a depressed and destructive autoimmune reaction. We measured apoptosis in the PBLs of seven patients with major depression and in age- and sex-matched controls. We observed significantly increased apoptosis in the PBLs of depressive patients (p < 0.05). These preliminary results could contribute to an understanding of the interactions of the CNS with the immune system, which could lead to the increased vulnerability of the CNS in depressive disorders. Further studies are needed to establish these results.

Immune activation in non-treated suicidal major depression.

In the following study we have analyzed cytokine secretion of T-cells of suicidal and non-suicidal depressed patients and healthy controls. It was found that T-cells of suicidal depressed patients have Th1 characteristics, while T-cells of non-suicidal depressed patients have Th2 characteristics. Th1 environment is associated with most of autoimmune diseases. It is thus speculated that Th1 activation in suicidal depression may reflect a unique form of autoimmune suicide.

Physiological reactions to a suicide film: suicide attempters, suicide ideators, and nonsuicidal patients.

A film about two teenagers who commit suicide was shown to three groups of psychiatric inpatients: 17 who had attempted suicide, 20 who had expressed suicidal thoughts, and 10 who were not suicidal. Anxiety before and after the film was evaluated with psychometric (anxiety rating scale) and physiological tools (heart and respiration rate, blood pressure, electromyogram). Values noted before and after screening, and the degree of change in these values, were compared. In addition, psychomotor agitation was rated at several points during the film. Most results were negative. The suicide attempters had significantly lower postscreening heart rates and a significantly lesser change in heart and respiration rates than the other two groups. The suicide attempters revealed an increase in psychomotor agitation until the discovery of the suicide and a decrease thereafter, whereas the agitation of the nonsuicidal patients continued to increase from the start to the end of the film. The study suggests that on some parameters, suicide attempters reveal less anxiety than nonsuicidal psychiatric patients following exposure to a simulated suicide. The reaction of suicide ideators falls somewhere between the two groups.

Modulation of murine systemic lupus erythematosus with peptides based on complementarity determining regions of a pathogenic anti-DNA monoclonal antibody.

Experimental systemic lupus erythematosus (SLE) can be induced in naive mice by immunization with a murine monoclonal anti-DNA antibody (mAb), 5G12, that bears a major idiotype designated 16/6 Id. Strain-dependent differences were observed in the proliferative responses of lymph node cells of mice immunized with two peptides based on the sequences of the complementarity determining region (CDR) 1 and 3 of mAb 5G12. The capacity of the peptides to bind to major histocompatibility complex class II molecules correlated with the proliferative responses. Immunization of high responder strains with the CDR-based peptides led to production of autoantibodies and clinical manifestations characteristic to experimental SLE. The CDR-based peptides could prevent autoantibody production in neonatal mice that were immunized later either with the peptide or with the pathogenic autoantibody. Furthermore, the peptides inhibited specific proliferation of lymph node cells of mice immunized with the same peptide, with mAb 5G12 or with the human mAb anti-DNA, 16/6 Id. Thus, the CDR-based peptides are potential candidates for therapy of SLE.

Short note: can depressive patients exploit the immune system for suicide?

It is suggested that patients with depression can exploit their immune system for suicide. This could be done passively by reducing the ability of the immune system to overcome factors threatening the integrity of the body, or actively by directing the immune system towards self constituents.

Hysteroscopy is superior to hysterosalpingography in infertility investigation.

BACKGROUND: The development of advanced endoscopic instrumentation in recent years has demonstrated the superiority of direct visual examination over radiographic demonstration of various body cavities. Just as laparoscopy has gradually taken a primary role in the surgical investigation of the ovulatory infertile patient, the role of intrauterine endoscopy in comparison to hysterosalpingography (HSG) needs to be reevaluated. METHODS: Four hundred and sixty-four infertile women had undergone both hysterosalpingography and a diagnostic hysteroscopy and the findings were analysed. RESULTS: Compared to hysteroscopy the sensitivity of HSG was 98%, but its specificity only 15%, the positive predictive value 45%, and negative predictive value 95%. On hysteroscopy a normal uterine cavity was found in 53% of the cases with a filling defect and in 56% of those with uterine wall irregularity on HSG. CONCLUSIONS: Hysteroscopy, a safe and rapid direct visualisation of the uterine cavity, is superior to HSG in the identification of intrauterine pathology. In view of the low positive predictive value and the low specificity of the HSG, we believe it should be replaced by the diagnostic hysteroscopy as a first line infertility investigation.