Search

Objective: Disasters can have impact on the demand and supply of blood, with such a difficult perspective, planning of an appropriate response to counterbalance the need for blood is of paramount importance. The primary objective of this study was to evaluate how the impact of blood imbalances may be absorbed by inert recruitment of donors during 2 life-threatening earthquakes that shook Taiwan on the same date in 2016 and 2018. Method: A retrospective database search from blood bank registries was developed. Results: Despite the public efforts to restrain the flow, a 3- to 4-fold increase in volunteers responded to the earthquakes. This surge alleviated after a day and did not contribute to sub-par collections. Those who donated more than usual immediately after the event were identified as first-time, younger, and female populations. The hospitals providing inpatient care to the injured transfused a slightly decreased amount of packed red cells, whereas the use of whole blood, platelets, and plasma remained stable. The inert recruiting was effective in reducing the duration of donor overabundance. Conclusion: Compared with other examples, the inert recruiting approach was effective in reducing the duration of donor overabundance to 1 day and may be useful for disaster preparedness of transfusion supplies. [ABSTRACT FROM AUTHOR]

Abstract Background The ability to acquire fully human monoclonal antibodies (mAbs) with pre-defined specificities is critical to the development of molecular tags for the analysis of receptor function in addition to promising immunotherapeutics. Yet most of the arriving affinity maturated and complete human immunoglobulin G (IgG) molecules, which are actually derived from single human B cells, have not widely been used to study the conserved self antigens (Ags) such as CD152 (cytotoxic T lymphocyte antigen-4, CTLA-4) because proper hosts are lacking. Results Here we developed an optimized protocol for site-directed in vitro immunizing peripheral blood mononuclear cells (PBMC) by using a selected epitope of human CD152, an essential receptor involved in down-regulation of T cell activation. The resultant stable trioma cell lines constantly produce anti-CD152 mAb (γ4λhuCD152), which contains variable (V) regions of the heavy chain and the light chain derived from the VH3 and Vλ human germline genes, respectively, and yet displays an unusual IgG4 isotype. Interestingly, γ4λhuCD152 has a basic pI not commonly found in myeloid monoclonal IgG4λs as revealed by the isoelectric focusing (IEF) analysis. Furthermore, γ4λhuCD152 binds specifically, with nanomolar affinity, to an extracellular constituency encompassing the putative second complementarity determining region (CDR2) of CD152, whereby it can react to activated CD3+ cells. Conclusion In a context of specific cell depletion and conditioned medium,in vitro induction of human Abs against a conserved self Ag was successfully acquired and a relatively basic mAb, γ4λhuCD152, with high affinity to CDR2 of CD152 was thus obtained. Application of such a human IgG4λ mAb with designated CDR2 specificity may impact upon and prefer for CD152 labeling both in situ and ex situ, as it does not affect the binding of endogenous B7 ligands and can localize into the confined immunological synapse which may otherwise prevent the access of whole IgG1 molecules.

CD152 or cytotoxic T lymphocyte antigen-4 (CTLA-4) is an essential receptor involved in the negative regulation of T cell activation. Because of its profound inhibitory role, CD152 has been considered a sound susceptible candidate in autoimmunity and a persuasive target for cancer immunotherapy for over a decade. However, the precise roles played by this molecule continue to emerge. In particular, recent evidence suggests that CD152 is also important in the homeostasis and function of a population of suppressive cells, termed regulatory T cells (Treg). In this review, we discuss the recent progress and main features of monoclonal antibodies (mAbs) targeting CD152 and examine how each mAb prepared to a distinct epitope may impact differently upon CD152 modulation depending on its demonstrated regulatory role acting as an agonist, antagonist, or inverse agonist.

Background: The ability to acquire fully human monoclonal antibodies (mAbs) with pre-defined specificities is critical to the development of molecular tags for the analysis of receptor function in addition to promising immunotherapeutics. Yet most of the arriving affinity maturated and complete human immunoglobulin G (IgG) molecules, which are actually derived from single human B cells, have not widely been used to study the conserved self antigens (Ags) such as CD152 (cytotoxic T lymphocyte antigen-4, CTLA-4) because proper hosts are lacking., Results: Here we developed an optimized protocol for site-directed in vitro immunizing peripheral blood mononuclear cells (PBMC) by using a selected epitope of human CD152, an essential receptor involved in down-regulation of T cell activation. The resultant stable trioma cell lines constantly produce anti-CD152 mAb (gamma4lambdahuCD152), which contains variable (V) regions of the heavy chain and the light chain derived from the VH3 and V lambda human germline genes, respectively, and yet displays an unusual IgG4 isotype. Interestingly, gamma4lambdahuCD152 has a basic pI not commonly found in myeloid monoclonal IgG4 lambdas as revealed by the isoelectric focusing (IEF) analysis. Furthermore, gamma4lambdahuCD152 binds specifically, with nanomolar affinity, to an extracellular constituency encompassing the putative second complementarity determining region (CDR2) of CD152, whereby it can react to activated CD3+ cells., Conclusion: In a context of specific cell depletion and conditioned medium,in vitro induction of human Abs against a conserved self Ag was successfully acquired and a relatively basic mAb, gamma4lambdahuCD152, with high affinity to CDR2 of CD152 was thus obtained. Application of such a human IgG4 lambda mAb with designated CDR2 specificity may impact upon and prefer for CD152 labeling both in situ and ex situ, as it does not affect the binding of endogenous B7 ligands and can localize into the confined immunological synapse which may otherwise prevent the access of whole IgG1 molecules.